Faculteit Toegepaste Wetenschappen Departement Burgerlijke Bouwkunde Laboratorium Bouwfysica Kasteelpark Arenberg 40, 3001 Heverlee Universiteit Gent Vakgroep Mechanica van Stroming, Warmte en Verbranding Sint-Pietersnieuwstraat 41, 9000 Gent Universiteit Gent Vakgroep Architectuur en Stedenbouw Plateaustraat 22, 9000 Gent Technische Universiteit Eindhoven Unit Building Physics & Systems P.O. Box 531, 5600 Eindhoven Wetenschappelijk en Technisch Centrum voor het Bouwbedrijf Departement Geotechniek en Structuren Departement Bouwfysica en Uitrustingen Poincarélaan 79, 1060 Brussel Physibel Heirweg 21, 9990 Maldegem
Daidalos Bouwfysisch Ingenieursbureau Oudebaan 391, 3000 Leuven
Ingenieursbureau Stockman nv Muinklaan 6, 9000 Gent
Heat, air and moisture performance engineering A whole building approach SBO project IWT 050154 Eerste jaarlijks rapport Staf ROELS, Erik DICK, Michel DE PAEPE, Arnold JANSSENS, Peter WOUTERS, Benoit PARMENTIER, Geert HOUVENAGHEL, Jan HENSEN, Bert BLOCKEN, Piet HOUTHUYS, Filip DESCAMPS, Piet DELAGAYE, Demir-Ali KÖSE, Sarah SACRE, Marnix VAN BELLEGHEM, Mohammad MIRSADEGHI, Daniel COSTOLA, Joachim VERHAEGEN, Thijs DEFRAEYE (verslag). September 2007
Inhoud Inhoud......................................................................................................................................... 1 1 Wetenschappelijk- technisch verslag ................................................................................. 3 1.1 Overzicht van uitgevoerde activiteiten....................................................................... 3 WP1.1 Wind pressure distribution ..................................................................................... 4 WP1.2 Driving rain load distribution................................................................................. 9 WP2.1 Development of HAM model............................................................................... 12 WP2.2 Experimental analysis on building enclosures ..................................................... 13 WP3.1 Convective heat exchange and summer comfort.................................................. 15 WP3.2 Development of CFD-HAM model...................................................................... 21 WP4 Towards an integrated approach ............................................................................. 26 WP5.1 Strategic and integrated planning of research activities....................................... 30 WP5.2 Strategic implementation of testing and simulation facilities .............................. 33 Referenties........................................................................................................................ 34 Appendices ....................................................................................................................... 35 1.2 Bijsturingen in het project ........................................................................................ 38 1.3 Beheer van het project.............................................................................................. 38 1.4 Haalbaarheid van het project.................................................................................... 40 1.5 Te beschermen resultaten ......................................................................................... 40 2 Utilisatieverslag................................................................................................................ 41 2.1 Valorisatiepotentieel: geactualiseerde visie ............................................................. 41 2.2 Overzicht van de uitgevoerde valorisatieacties........................................................ 43 2.3 Bescherming projectresultaten ................................................................................. 46 3 Financieel verslag............................................................................................................. 47 3.1 Prestatietabel ............................................................................................................ 47 3.2 Prognose voor komend projectjaar........................................................................... 48 3.3 Financiële verantwoording....................................................................................... 48
1 Wetenschappelijk- technisch verslag 1.1 Overzicht van uitgevoerde activiteiten Het onderzoekswerk is georganiseerd in vijf werkpaketten, welke op hun beurt nog verder onderverdeeld zijn: WP1 Outside boundary conditions WP1.1 Wind pressure distribution WP1.2 Driving rain load distribution WP2 Building envelope WP2.1 Development of HAM model WP2.2 Experimental analysis on building enclosures WP3 Building interior WP3.1 Convective heat exchange and summer comfort WP3.2 Development of CFD-HAM model WP4 Towards an integrated approach WP4.1 Development of a prototype software environment WP4.2 Development of a coupling necessity decision procedure WP4.3 Experimental validation WP5 Establishment of a knowledge platform WP5.1 Strategic and integrated planning of research activities WP5.2 Strategic implementation of testing and simulation facilities Dit verslag beschrijft de onderzoeksactiviteiten van het eerste projectjaar lopende van 1 september 2006 tot 1 september 2007. Dit deel van het verslag is opgemaakt in het Engels omdat dit de voertaal is voor publicaties en wetenschappelijke rapporten en een aantal onderzoekers Nederlands niet als moedertaal hebben.
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WP1.1 Wind pressure distribution Objectives WP1.1 emphasises the distribution of pressure differences across the building envelope due to wind flow. This subtask is subdivided in two parts: WP1.1.1 Some sets of full-scale measurements will be recorded regarding the wind pressure distribution on the building envelope of the building “Windhouse” of the Laboratory Structures of BBRI, located in Limelette. The data will be used to asses the numerical predictions with CFD (Computational Fluid Dynamics). WP1.1.2 Numerical simulations of the air flow around a building will be performed. Different hybrid RANS-LES models to describe the turbulence are tested. The calculations will provide, among other numerical results, the pressure distributions at various locations on the building surface. The obtained data will be compared with the experimental pressure data sets provided by WP1.1.1.
Description of work WP1.1.1 Experimental analysis of wind pressure distribution over a building envelope As it has been clearly demonstrated by different authors and by a specific first comparison between full-scale measurements and wind-tunnel tests on the Windhouse building of BBRI, the role of the lateral turbulence intensity (Iy) is of great importance to explain the discrepancies between peak pressures recorded in full-scale vs. wind-tunnel experiments. In function of the time-averaging procedure for analysing the pressures, these discrepancies can be very high. Hence, it was decided, as a first step of the wind and pressure data sets preparation, to perform a complete, more explicit analysis of the wind flow around the building. This will allow the researchers to interpret the correlations with the future predictions that will be obtained with numerical simulations (WP1.1.2). Having this considered, it has been decided to install three additional meteorological masts around the building with specific anemometers in order to get a detailed evaluation of the turbulence intensities of the incoming wind flow around the building. The location of these new masts was determined according to the precision needed by the numerical simulations and to be able to identify the influence of the flow pattern on the windward and leeward pressures. The masts are lattice structures with a height of 10 m. These will be equipped with sonic and 3-cup anemometers, as described below. The location of the masts is illustrated in Figure 1. Two masts are located near the first existing (original) mast to obtain a spatial grid analysis of the wind flow upstream of the building. A last mast will be located at about 20 m downstream of the Windhouse building. The sensibility to the vibrations of the masts on the measurements has been studied and could be neglected. Unfortunately, the masts are still not fully operational because of delay problems (9 months) with the urban planning commission of Limelette for the licence to build. However, it is expected that the whole system will be ready by the end of October 2007. The building contractor has just started the construction works.
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Figure 1: Location of the new meteorological masts around the Windhouse building at BBRI in Limelette.
In order to evaluate the structure of the wind flow with more accuracy, ultrasonic anemometers were considered. After an analysis and a comparison of the available equipment, 2 WindMaster ultrasonic anemometers from Gill Instruments Ltd. were bought. These allow to determine the wind speed in the 3 principal directions (U, V, W) and, more important, the associated turbulence intensities (Iu, Iv and Iw). The sample rate is 32 or 40 Hz, the resolution is < 0,01 m/s and the accuracy is lower than 1,5 % RMS.
Figure 2: Ultrasonic anemometer
The prevailing wind directions around the building are given in Figure 3. It is clear that the southwest direction is dominant. A first measurement of the longitudinal turbulence intensity was obtained with a simplified system up to 5 m height and is presented in Figure 4. As can be observed from Figure 4, the turbulence intensity is highly dependent on the wind direction. More results will demonstrate this for the other (principal) directions. Additional 3-cup anemometers were also bought to obtain information on the wind speed along the altitude around the building. These will also be installed on the masts at different heights (5 m and 10 m).
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Figure 3: Prevailing wind directions in Limelette
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Figure 4: Analysis of the longitudinal turbulence intensity of the wind around the Windhouse building in Limelette (U > 5 m/s).
WP1.1.2 Development of a hybrid RANS-LES technique of flow over buildings From a computational point of view it is not feasible to perform Large Eddy Simulations (LES) of flow around buildings. With this technique, the large turbulence structures in the flow are resolved and the small structures are modelled. A very fine mesh near the building walls is required to accurately resolve the flow. This leads to very large computational costs. On the other hand, simulations with Reynolds Averaged Navier-Stokes equations (RANS) result in very poor predictions of the flow field over a building since this methodology requires modelling of all the turbulence structures. That is the main reason why a hybrid model can be of interest. In such a model an unsteady Reynolds Averaged Navier-Stokes model is used in the near-wall regions, while far from the wall a sub-grid scale (SGS) model is used within an LES-formulation. In this way the best qualities of RANS and LES are combined in one model. The use of a RANS model in the near-wall regions allows using much coarser meshes in those regions which saves computational time. Numerical simulations have been done mainly on flow over a periodic part of a square section of a tower building. In a first stage a coarse mesh (Figure 5) is used and comparison with available experimental data is made. Depending on the agreement with the experimental data, IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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the mesh will be refined if necessary. Dependency on inflow boundary conditions will also be investigated. Three hybrid models are considered and will be compared in order to determine which of them gives the best results: the Detached Eddy Simulation (DES) model, the k-l model of Davidson and the hybrid model developed at the department of Flow, Heat and Combustion Mechanics at UGent by C. De Langhe: ε-l model. Since only the DES model is implemented in the CFD software that was used (Fluent), the other two models needed to be programmed. This has been done by means of User Defined Functions (UDF). Different aspects of the qualities of the models have been investigated. For the time being, the conclusion is that the k-l model is somewhat superior to the other two models, although results do not match perfectly with experimental data. Possible improvements of the model will further be investigated. This model will then be used to provide the pressure distribution for the data of WP1.1.1. The last couple of week’s two simulations with the DES model have been performed for flow over a cubic building with dimensions 10 m x 10 m x10 m (see Figure 6 and Figure 7). In the first simulation a uniform inlet velocity profile (10 m/s) was assumed, while in the second one a logarithmic inlet profile was used.
Figure 5: Cross section of the coarse mesh (8.400 cells)
Figure 6: Contours of mean static pressure on the front and back sides of the cube
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Figure 7: Contours of mean static pressure on the top of the cube
Deliverables WP1.1.1 • Ultrasonic anemometers were purchased and calibrated • Preliminary measurements of the wind speed, wind direction and turbulence intensity were made around the Windhouse building at a height of 5 m. • The construction of three meteorological masts around the Windhouse building has started. WP1.1.2 • The researcher became familiar with the different turbulence modelling techniques. • Various turbulence models were implemented in the CFD software package by means of User Defined Functions.
Planning WP1.1.1 • During the next weeks, the construction of the masts will be completed. A complete calibration of the acquisition system will be performed and an analysis of the turbulence intensities (3 directions) will be accomplished. • A recording period will begin on the Windhouse building during the winter in order to get all the data sets (wind and pressures on specific locations on the building) allowing a comparison with numerical simulations. WP1.1.2 • Additional simulations with the DES and the other two models on the periodic part of the square section tower building and on the cubic building will be performed and the results will be compared with experimental results. The aim is to decide which of the models has fundamentally the best qualities. • Analysis of the dependency on inflow boundary conditions and on the size of the computational domain around the building. • Grid sensitivity analysis. The aim is to determine how coarse a grid might be for a realistic flow simulation with DES. • Fine-tuning of the chosen model. Some small modifications might be beneficial for the final quality.
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WP1.2 Driving rain load distribution Objectives WP1.2 emphasises the effect of wind-driven rain on the heat and mass transfer in the building envelope. This subtask is subdivided into several parts: WP1.2.1 In this subsection, laboratory and in situ experiments of contact phenomena of driving rain impinging on different building materials are carried out. The final amount of water that may enter the building enclosure will be determined by splashing effects, adhesion, evaporation, run-off and capillary absorption. All these phenomena strongly depend on the material properties of the building enclosure. WP1.2.2 Numerically, the transformation of individual rain drops, absorbed by the building material towards a smeared wetting as assumed in building envelope models, will be investigated. In addition, a run-off model for rain water run-off on capillary active materials will be developed. WP1.2.3 The research of the previous two subsections was conducted in strong collaboration with a PhD student working on a K.U.Leuven OT-project where the contact phenomena (bouncing, splashing and spreading) and surface phenomena (absorption, evaporation and run-off) are also of interest. Out of this research it has become clear that the outside boundary conditions, namely convection and radiation, have a large impact on the evaporation at building façades wetted by wind-driven rain. Therefore the focus of the PhD student working on this SBO project (PhD1) will be mainly on these topics and an additional subsection (WP1.2.3) has been introduced.
Description of work WP1.2.1 Laboratory and in situ experiments of contact phenomena of driving rain impinging on different building materials. Contact phenomena of a raindrop impinging on a building material were investigated with a laboratory set-up. With this set-up raindrops of different sizes were released from a certain height until they reached terminal velocity after which they impinge on the building material. Different building materials and impact angles were investigated. As the raindrop trajectory was captured by a high-speed camera, the different types of contact phenomena could be distinguished, namely bouncing, splashing and spreading. A correlation for the spreading length as a function of the impact angle and the droplet diameter was derived out of the experimental data. An experimental setup for field measurements of wind-driven rain loads and the response of walls was developed at the VLIET building for validation purposes. Measurements of nearwall wind speed and direction, wind-driven rain intensity and material weight are possible. A preliminary measurement campaign was carried out and more extensive ones will follow. WP1.2.2 Development of a water uptake and run-off model for building materials. A simple run-off model was implemented in HAMFEM, which is an in-house HAM modelling tool developed by the Laboratory of Building Physics at the K.U.Leuven, and preliminary simulations were performed. More extensive simulations are planned. Moreover, 2D simulations of a horizontal cut of a cubic building model were performed with HAMFEM for several successive rain events in order to asses the response of the building envelope. IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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WP1.2.3 Laboratory experiments and numerical modelling of the influence of outside boundary conditions on the heat and mass transfer at building façades wetted by wind-driven rain. Complementary to the previous two subtasks (WP1.2.1 and WP1.2.2), this additional subsection will asses the effect of the outside boundary conditions, such as convection and radiation, on the evaporation at building façades wetted by wind-driven rain. As mentioned before, this information was found to be of significant importance in the assessment of the response of building walls after a rain event for the numerical simulations described in WP1.2.2. In a first stadium, only convective heat and mass transfer was considered and only forced convection was taken into account since this corresponds to high wind speeds and will consequently result in high convective heat transfer coefficients (CHTC) and convective mass transfer coefficients (CMTC). Because of the strong relation of heat and mass transfer with the flow field around a building, the relevant literature regarding atmospheric boundary-layer flow and its numerical modelling techniques has been reviewed. Moreover, the review also included an overview of full-scale measurements, wind-tunnel tests and numerical simulations of convective heat transfer at building façades. There are few experiments available for convective mass transfer since CMTC are generally obtained by the heat and mass transfer analogy. These have also been included in the review. A numerical study with CFD (Fluent) was carried out to asses the convective heat transfer on a heated 10 m high, cubic building submersed in an atmospheric boundary layer (see Figure 8). The RANS approach was used to model turbulence. The influence of different approach flow profiles, wind directions and thermal boundary conditions was investigated. Moreover, different near-wall modelling techniques have been compared. The amount of heat transfer, represented by the CHTC, was correlated with the mean wind speed at a height of 10 m above the ground. In the previous research, heat transfer was entirely solved within the CFD package. Since combined heat and mass transfer in solid materials is not implemented in the software, the program is coupled (explicit) with HAMFEM. The air flow is entirely solved within the CFD package whereas the heat and mass transport in the solid material is solved within HAMFEM. Validation simulations are currently carried out in order to validate the coupled program. Furthermore, an experimental setup was designed to provide validation data regarding the convective heat and mass transfer at surfaces of building materials predicted by the coupled CFD-HAMFEM program. It is a small wind-tunnel where turbulent channel flow is produced over a building material sample, mounted flush with the channel walls. The effect of different boundary conditions and surface texture can be investigated. The wind tunnel will be constructed within the following months.
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Figure 8: Cubic building model (heated from the inside) submerged in the atmospheric boundary layer: example of heat flux distribution (left) and computational grid (right)
Deliverables WP1.2.1 • A correlation for the spreading length of a raindrop is available as a function of the impact angle and the droplet diameter. • An experimental setup for field measurements regarding wind-driven rain loads was developed at the VLIET building. WP1.2.2 • A simple run-off model is developed. WP1.2.3 • A prototype version of the HAMFEM program, which is adjusted so it can run together with Fluent is developed.
Planning WP1.2.1 • A more extensive measurement campaign will be performed to obtain a larger dataset regarding the response of walls on wind-driven rain. WP1.2.2 • The run-off model will be extended. WP1.2.3 • Regarding the CHTC distribution on the building façade, different building configurations and more accurate unsteady simulations such as DES will be considered. • The adjusted HAMFEM program will be validated and optimised. • The wind tunnel test setup will be constructed.
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WP2.1 Development of HAM model Objectives The aim of this subtask is to develop a comprehensive building envelope model for the coupled analysis of heat, air and moisture transport through building enclosures. The model will be based on existing scientific models (most dealing with a part of the problems) available from the partners. Because of the different time-scales between heat, moisture and air transport, and the corresponding numerical problems, a stabilised solution method will be applied when dealing with air transport.
Description of work The work package researcher got familiar with numerical modelling and gathered information and knowledge on existing HAM-models. In addition, he studied in depth the HAMmodelling program HAMFEM, developed at the K.U.Leuven. In a WP4-meeting in May 2007 the decision was made to couple HAMFEM with ESP-r. In order to get HAMFEM and EPS-r to communicate, a first test-case was determined. The setup has been defined in its geometry, indoor and outdoor boundary conditions, ….
Deliverables • •
The researcher became familiar with HAMFEM, the HAM-modelling tool developed by the Laboratory of Building Physics of the K.U.Leuven. A review paper on modelling of air transport in building envelopes and porous materials is in preparation.
Planning •
The decision has been made to focus on HAMFEM in the further course of the project and to ‘upgrade’ it to a 1, 2 and 3D HAM-modelling tool. Therefore, the modelling of air transport has to be solved in combination with heat and moisture transport. These so called advection-diffusion or convection-diffusion problems require a complex solution (i.e. Petrov-Galerkin, discontinuous Galerkin, …). Similar problems have been solved before, however, none of them have been implemented and tested for the application in HAM-problems. Since it is not possible to compare every possibility, further research should make it possible to choose and compare a few. In order to attain more insight in the complexity of HAM-modelling and to overcome the difficulties in numerically solving HAM-problems further research will be done in the next few months. • During measurements on the VLIET-building setup, the experimental setup will be simulated with HAMFEM (without air component) in order to evaluate the effect and importance of airflows and/or air leakage. In a later stage of the project the ‘upgraded’ version of HAMFEM will be used to fully simulate heat, air and moisture transfer in building components. • In the framework of WP4 the necessary data for the coupling of HAMFEM with ESP-r will be provided.
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WP2.2 Experimental analysis on building enclosures Objectives This subtask focuses on experimental analysis of building enclosures. Measurements will be performed at the VLIET test-building of the K.U.Leuven both on masonry and lightweight constructions. The measurement data will be used to validate the developed numerical model in WP2.1.
Description of work During the first year a test-setup was built at the VLIET-building of the K.U.Leuven in Heverlee. In the building a terraced house has been constructed. The timber frame walls have a 9 cm mineral wool filling in between the rafters and an extra 8 cm of XPS insulation at the outside. Also, a floor was added to simulate a ground and first floor level. Both levels are connected with an opening in the floor, which can be closed with hatches. This allows measuring at both levels separately or combined. The setup is constructed as air tight as possible, in order to attain a high accuracy in the measurements. Walls, floors and ceilings have a 15 mm multiplex finish, covered with an air and vapour retarder. Air tightness tests for the ground level part will be carried out in September 2007.
Figure 9: VLIET-building test setup
Deliverables • •
Design and construction of the experimental setup at the VLIET-building of the K.U.Leuven. A paper on the VLIET-building test setup and first measurements is in preparation (submitted for the Nordic Symposium on Building Physics 2008 in Copenhagen, 1618 June 2008).
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Planning •
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Measurements will be done on the ground level part (with closed hatches). The SWwall of the test section is a cavity wall, with a plaster finish at the inside. The NE-wall consists of three separate wall-sections, each with different air tightness. The measurements on the NE-walls will start in October 2007. During the following months the NE-walls will be closely monitored and analysed, during which several boundary conditions will be changed, i.e. adding extra ventilation (infiltration and exfiltration). These measurements should give a good idea of the impact of wind flows, air tightness and in- and exfiltration on the hygrothermal behaviour of the NE-walls and on whole building level. Afterwards, adjustments will be made to the test-setup (additional ventilation opening in SW-wall, …). These new and different setups will also be measured and analysed. In addition, the upper level will be made operational in the next few months and at that time the roof sections will also be studied and monitored.
Figure 10: Airflow patterns in the test setup
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WP3.1 Convective heat exchange and summer comfort Objectives WP3.1 will focus on the convective heat transfer in rooms and offices and its impact on summer comfort performances by solar processing, intensive (night) ventilation and thermally active flooring. Engineering the summer comfort performances depends on the other hand to a large extent on a reliable prediction of the local heating through solar irradiation and the prediction of wind pressures around buildings for ventilation (WP1.1). WP3.1 is subdivided into four parts: WP3.1.1 An experimental analysis of convective heat transfer between the ventilation air and the building surface will be performed. This work focuses on a single zone and will be done in the rotating PASLINK-cell available at BBRI, a highly instrumented test facility. WP3.1.2 An experimental analysis of solar heating and intensive ventilation and its impact on summer comfort will be conducted. WP3.1.3 A numerical prediction of ventilation and local heating through solar irradiation inside buildings will be performed. The solar illuminated patterns on inside surfaces through direct solar radiation will be calculated and converted to local heat powers. For the ventilation, input data from WP1.1 will serve as boundary conditions. The CFD simulations will be coupled with a multi-zone building simulation model and the predictions will be validated by comparison with the test results. WP3.1.4 The numerical methods that are developed will be validated with data measured in projects realised by the industrial partners.
Description of work WP3.1.1 Experimental analysis of convective heat transfer between the ventilation air and the building surface Additional to the experimental research of the heat transfer and other information of the flow field in the room, numerical calculations by means of CFD will also be used in this subtask. Typical outputs of a CFD simulation are three-dimensional spatial distributions of: (1) air velocity for all three directional components, (2) air temperature, (3) relative humidity, (4) turbulence intensity and (5) different contaminants concentrations. With these distributions a better air quality and thermal comfort analysis can be performed than any multi-zone or zonal model. A CFD simulation is performed to investigate the convective heat transfer at walls in an enclosure. However, for the modelling of CFD simulations different assumptions have to be made. Therefore the sensitivity of some modelling and calculation parameters is examined. Experience indicates the limitations of the current available CFD-methods, with respect to reliability and necessity to validate CFD-results of typical indoor airflow patterns. As an indication of the reliability of the CFD-results the calculated convective heat transfer coefficients (CHTC) at the ceiling of a room are compared with the appropriate empirical CHTC correlations. Therefore, an extensive literature review of the relevant empirical CHTC correlations in building design is performed (Sacré et al., 2007a). For each different flow regime an experimental correlation is derived. However, as some of the correlations include a length scale, the use of the correlation for different room dimensions must be performed IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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carefully. Also the reference temperature, which has a significant influence on the CHTC, may differ for each correlation. Therefore, the details of the flow regime, the derivation of the CHTC, the dimensions of the experimental chamber and other specifications must be known before applying the CHTC correlation. For the calculation of the CHTC at cooled ceiling surfaces for natural convection, Novoselac (2005) was the first to develop a correlation by means of an experimental setting with a cooled ceiling. The previously used correlations in building design were all based on measurements at heated floors (Alamdari and Hammond, 1983; Awbi and Hatton, 1999). The empirical CHTC correlation used for the comparison of the CFD-calculated CHTC at the cooled ceiling are represented in Table 1. The local air temperature at 100 mm of the cooled ceiling surface is used as the reference temperature. Table 1: Empirical convection correlations at cooled ceilings
Author Surface type Natural convection Min et al Heated floor (1956) (Tsurface > Tair) Alamdari and Hammond (1983)
Ceiling (Tsurface < Tair)
Novoselac (2005) Mixed convection Awbi and Hatton (2000)
Ceiling (Tsurface < Tair) Jet over heated floor (Tsurface > Tair)
hc correlation h c = 2.416
(Tair
− Tsurface )
0.31
D h0.08
6 ⎧⎡ 1/ 4 ⎛ ∆T ⎞ ⎤ ⎪⎢ ⎟⎟ ⎥ + 1.63∆T1/ 3 ⎨ 1.4 ⋅ ⎜⎜ D ⎝ h ⎠ ⎥⎦ ⎪⎢⎣ ⎩
[
1/ 6
⎫ 6⎪ ⎬ ⎪ ⎭
]
2.12 ⋅ ∆T 0.33 1 / 3 .2
3 .2 ⎧⎡ ⎫ ⎪ 2.175 0.308 ⎤ 0.575 0.557 3.2 ⎪ ( ) T U ∆ ⎥ + 4.248(W ) ⎨⎢ 0.076 ⎬ ⎪⎩⎣⎢ Dh ⎪⎭ ⎦⎥
[
]
where Dh = hydraulic diameter (= 4A/P) [m], A = area [m²], P = perimeter [m], W = width [m] and U = velocity [m/s] The dimensions and the construction of the 3-D model are represented in Figure 11. Air enters and leaves the room at the top of the room. There are four isothermal walls in the room (floor, east, west and north wall), a hot wall (south wall) and a cold wall (ceiling). A convective heat source is represented by a rectangular block. The CHTC’s are calculated for different lowered ceiling configurations (Figure 11). The specifications of the model and the simulation approach in Fluent are described in Sacré et al. (2007b). First a sensitivity analysis was performed to investigate the influence of the choice of different types of models and calculation parameters on the predicted values of CHTC. The analysis showed that the choice of the turbulence model was not significant. On the other hand the use of standard wall functions has a large influence. The influence of the jet (v = 0.2 m/s) is negligible on the CHTC, as well as the modelling of the density with the incompressible ideal gas law.
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Figure 11: 3-D room geometry for CFD-simulation
Figure 12: CHTC at a cooled ceiling: empirical correlations and simulated values
The simulated CHTC’s at the cooled ceiling and the empirical correlations are represented in Figure 12 as a function of the temperature difference between ceiling surface and air (mean temperature at 100 mm from ceiling surface). It is obvious that the results for the completely lowered ceiling configuration yield close to the correlations of Novoselac (2005) and of Awbi and Hatton (2000). The CHTC for the other ceiling configurations lies closer to the correlation of Alamdari and Hammond (1983). The CFD-calculated CHTC’s thus lie in the range of the empirical convection correlations at a cooled ceiling surfaces. Therefore, it can be concluded that CFD can be used as a cheap tool (no experimental chamber needed) for the prediction of CHTC’s. However, the modelling of natural convection with Fluent is not evident. The calculations still have a long calculation time and convergence is not always achieved easily. Apart from the numerical simulations, experimental measurements in the PASLINK cells are also planned, as described below. WP3.1.2 Experimental analysis of solar heating and intensive ventilation and its impact on summer comfort No actions have been undertaken yet to setup a measurement campaign but a working meeting is planned to discuss the experiments. Probably, the PASLINK cells will also be used for these experiments.
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WP3.1.3 Numerical prediction of ventilation and local heating through solar irradiation inside buildings Physibel implemented a 3D solar processor in VOLTRA v6.0. In this model, the direct and diffuse solar radiation on a horizontal surface from a climate data file are converted at each calculation time step to direct and diffuse solar radiation on the object surfaces taking into account the geographical location (latitude, longitude, time zone), day of year, clock time, surface orientation (compared to north direction) and surface tilt (height angle above horizon). The diffuse solar radiation on an exterior material surface also depends on the view factor to the open sky and is calculated using Muneer’s diffuse radiation model (also used in the building simulation program CAPSOL developed by Physibel). Direct radiation is reflected using a reflection factor which may be function of the angle of incidence. Diffuse radiation is reflected using a diffuse reflection factor. Reflected radiation from an exterior material surface is lost (as in CAPSOL). A global ground reflection factor (or albedo) allows taking into account the reflected radiation from the environment onto the object surfaces. Radiation on transparent materials is transmitted to internal zones. Transmitted direct radiation is projected on internal walls following the solar rays. Transmitted diffuse radiation is distributed on all internal walls proportional to the view factors from the inside surface of the transparent material to the other internal walls. Direct radiation on an internal wall surface is reflected using a reflection factor which may be function of the angle of incidence. All reflected radiation at an interior material surface is diffuse and is redistributed to the other interior surfaces proportional to the view factors. An interior material surface may also be part of a transparent material, through which the solar radiation is further propagated. The scheme of successive internal reflections and transmissions is solved using a radiosity method. The view factors can be obtained from a prior view factor calculation using a coarser grid (to speed up the processing time and to reduce the required memory space). The absorbed solar radiation upon exterior and interior material surfaces and inside transparent materials is converted to time dependent node powers, which are considered as additional boundary conditions to the thermal system. These absorbed solar fluxes can be used in graphic files or written to a text file, which allows exchange of data to other models. Figure 13 shows an example. Measuring equipment was developed to validate the solar processor but due to bad measuring conditions in summer, no measurement campaign was carried out.
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indoors
outdoors Brussels 9 June
sunshade
clear glazing glazing αs= 0.2 ρs = 0.5
τs = 0.3
clear glazing
Figure 13: Predicted absorbed solar flux at an exterior façade with sunshade
WP3.1.4 Validation of the numerical methods with data measured in projects realised by the industrial partners No measurements for validation purposes have been carried out yet. However, case studies are planned on the prediction and optimisation of summer comfort applying different calculation methods: solar processor and 3D transient thermal simulation, multi-zone building simulation coupled with CFD (interior and exterior), and classical multi-zone. Well chosen projects realised by the industrial partners (Daidalos, Stockman) will be chosen for these case studies. The results of the numerical methods will be compared with data measured in the projects. The projects include an office building with natural night ventilation (UnilanQuickstep) and cooled ceilings, and a high rise building with exterior solar protection (VRT building).
Deliverables WP3.1.1 • Two internal reports on the extensive literature review and the performed CFD calculations regarding the natural convective heat transfer coefficient have been composed. WP3.1.2 • No deliverables have been obtained yet. WP3.1.3 • An extension of the program VOLTRAv6.0 has been made. • Measuring equipment was developed to validate the 3D solar processor. WP3.1.4 • Preparations were made for the two planned measurement campaigns. IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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Planning WP3.1.1 • Validation experiments will be designed in the PASLINK cells available at BBRI, studying the interaction between solar gains, thermal storage and ventilation. A first proposal is to focus the measurements on the performance of thermally active concrete floors in combination with raised floors and suspended ceilings. WP3.1.2 • Proper experiments will be determined during the planned working meeting. WP3.1.3 • A measurement campaign is planned to provide validation data for the 3D solar processor. • The 3D solar processor will be validated with experimental data and if necessary, adjustments will be made to the software. WP3.1.4 • Measurement campaigns will be set up for two buildings, realised by the industrial partners.
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WP3.2 Development of CFD-HAM model Objectives In WP3.2, the emphasis goes to a correct and reliable implementation of moisture transport in CFD-calculations. The enrichment of classical CFD to a CFD-HAM model and the formulation of efficient solution strategies by the build in of UDF’s (User Defined Functions) necessitates an in depth study. WP3.2.1 In order to validate the CFD-HAM model, small-scale laboratory tests will be performed in wind tunnels. The two-dimensional air speed pattern and size of the boundary layer will be measured by Laser-Doppler-Anemometry as well as the temperature and relative humidity profiles. This information is used to determine the convective boundary coefficients. The experiments consist in the moistening (drying) of samples by moist (dry) air. WP3.2.2 A HAM-model will be developed in the CFD-environment. Current state of the art CFD does not offer the possibility to describe the interaction between fluid and solid material for complex geometries in an efficient and satisfying manner. In these cases, the boundary layer problem can only be solved using very fine grids leading to unreasonably high calculation times. Therefore in this project adequate models using UDF’s will be developed and implemented in CFD: i.e. in the boundary cells (empirical) relations for the convective coefficients are built in. WP3.2.3 Validation of the numerical methods with data measured in projects realised by the industrial partners
Description of work WP3.2.1 Laboratory test for the validation of the CFD-HAM model The surface transfer coefficient for mass transfer is usually unknown in building simulation models. The standard procedure is using the analogy between heat and mass transport to calculate this coefficient. However, this analogy does not always apply. In the SBO project coupled CFD-HAM models are being developed which can be used to simulate both the surface transfer coefficient for heat transfer as for mass transfer. However these new models require validation. Therefore there is a need for an experimental setup which can be used to study mass surface transfer coefficients and can provide experimental data for the validation of newly developed models. During the previous project year, a climate test chamber has been developed for which the schematics are shown in Figure 14. The test chamber consists of two separate chambers, denoted as outer and inner chamber, respectively. The inner chamber is built upon two rails, which enables the researcher to separate the two chambers and modify them at any moment. The outer chamber is used to keep the ambient conditions of the inner chamber constant during the tests. The inside of each of the two chambers can also be adapted to any test circumstances thanks to the use of two isolated doors. The test chamber has a height of 1,8 m, a width of 1,8 m and a depth of 2,1 m. The climate control unit is located outside the outer chamber. A robot arm is to be placed inside the inner chamber which can move in 2 directions and is to be controlled from a computer. This allows the measurement of multiple points in the air near a wall specimen. The robot arm will be equipped with a hot-wire anemometer, a relative IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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humidity sensor and a thermocouple. At the same time the weight change of a test specimen and the relative humidity inside the test specimen are to be continuously measured to indicate the water absorption of the test specimen. This data can then be used to calculate the mass surface transfer coefficients for the test specimen.
Figure 14: Configuration of test facility
The climate control unit consists of four different devices, which can be found in this order along the direction of air flow: • a 76 m³/h recirculation fan which speed can be manually controlled to attain different flow rates. • a 2 kW compact heat exchanger cooled with ethanol at –10°C. The ethanol pump feeding this heat exchanger provides a constant flow of 8 kg/min. The heat exchanger serves two purposes: it dehumidifies and cools the air flow. • a 2 kW electric reheat coil for fine temperature control. The power provided to this coil can be regulated by use of a thyristor control. • a steam humidifier with a maximum steam flow of 2 kg/h. The humidifier uses a relative humidity setpoint and an internal PI controller to regulate the steam flow. Measured parameters include temperature, relative humidity and air flow rate. The objective of the climate control unit is to control the temperature and relative humidity of the jet entering the climate chamber. The throw of the attained jet can reach the opposite side of the inner chamber. Some additional work is planned for the test chamber: • A load cell has to be installed in the test chamber. • The steam humidifier currently installed, doesn’t satisfy. An alternative has to be developed. A dosing pump and resistive heated plate could bring a solution. • A hot-wire anemometer has been ordered together with a robot arm, but they still have to be implemented and tested. • Current measurements and calculations suggest that the placement of a mixing chamber after the humidifier could increase controllability and accuracy. WP3.2.2 Development of a CFD-HAM-model CFD is a simulation tool which allows for the modelling of fluid flow. It can be used to describe the air flow near building materials inside or outside buildings. CFD can hence supply valuable information on local air temperature, relative humidity and velocity near these building materials. Such information provides the necessary boundary conditions for the simulation of Heat, Air and Moisture (HAM) transport inside porous building materials. In traditional HAM models average air temperatures and humidity are used together with constant surface transfer coefficients to generate the necessary boundary conditions. Coupling a CFD code to a HAM material model allows for the use of the correct local boundary IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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conditions and hence the simulation of local heat and moisture transport in the porous materials. This results in the knowledge of local temperatures and humidity in the porous material, the possibility to assess the risk of moisture related damage to the material and a better and more detailed understanding of the drying or wetting process of the porous materials. To couple the CFD code and the HAM material model the choice was made to include the HAM model in the CFD code. The CFD solver is used to solve all the transport equations: in the fluid (air), the standard CFD transport equations are solved while inside the porous material these standard transport equations are replaced with the HAM transport equations. The CFD code used for this coupling is Fluent because it allows the user to implement its own transport equations. The HAM transport equations which need to be implemented in the CFD code have to be valid for vapour transport in hygroscopic porous materials. Inside the porous materials it is assumed that no convection exists and that the heat and moisture is solely transported by diffusion. Up to now only isothermal moisture transport has been modelled. For this isothermal case the moisture transport equation in the material can be written as: ⎛ ⎞ ⎛ ⎞ ⎛ ⎞ D D D ∂w ∂w ∂φ ∂γ ∂γ = ∇. ⎜ ρ air air ∇γ ⎟ ⇔ = ∇. ⎜ ρ air air ∇γ ⎟ ⇔ C ( γ ) X ( γ ) = ∇. ⎜ ρ air air ∇γ ⎟ ⎜ ⎟ ⎜ ⎟ ⎜ ⎟ ∂t ∂φ ∂γ ∂t ∂t µ (γ ) µ (γ ) µ (γ ) ⎝ ⎠ ⎝ ⎠ ⎝ ⎠
with w the moisture content (kg/m³), ρair the air density (kg/m³), Dair the vapour diffusion coefficient, µ the vapour resistance factor (-), γ is the mass fraction of vapour in air (kg/kg), φ is the relative humidity (-), C the hygroscopic moisture capacity (kg/kg) and X the derivative of relative humidity to the mass fraction of vapour. The above transport equation is written in function of the mass fraction of vapour in air (γ) which is a parameter that is continuous at the air-material interface. To solve this equation material data is required on the sorption isotherm and on the water vapour permeability. This material data is necessary to determine the moisture capacity and the vapour resistance factor. Once this data is known the moisture transport equations in the air and the material can be solved together using the CFD solver. To validate the coupled CFD-HAM model a benchmark experiment from literature was simulated. The experimental setup is discussed in Talukdar et al. (2007a, 2007b) and Figure 15 gives an overview of this setup. The experiment which was simulated is a common exercise defined in Talukdar et al. (2006). In this common exercise the studied porous material is gypsum board instead of spruce plywood as in Talukdar et al. (2007a, 2007b). Five different cases were simulated. A short description of these cases is given in Table 2.
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Figure 15: Experimental setup of the benchmark experiment of Talukdar et al. (2007a, 2007b)
Table 2 Description of the simulated test cases
Test 1 Test 2 Test 3 Test 4 Test 5
gypsum board, Re=2000, 24h loading gypsum board, Re=2000, 8h loading gypsum board, Re=5000, 24h loading gypsum board + acryl coating, Re=2000, 24h loading gypsum board + latex coating, Re=2000, 24h loading
To simulate the test cases a two dimensional grid was made that represents the porous material and the air flowing in the tunnel above the material. The coupled CFD-HAM model is then used to simulate the moisture exchange between the air and the porous material. Simulations and experiments show that the moisture transport in the material can be considered one dimensional. To validate the model the measured relative humidity at two different depths in the material (12.5mm and 25mm) is compared with the simulated relative humidity at that specific depth in the centre of the material. The results of these validation tests are given in Figure 16. This figure shows that the agreement between the experiment and the simulation is excellent for the absorption phase, while for the desorption phase the agreement is still very good. The somewhat less agreement for desorption is probably caused by the hysteresis effect.
Figure 16: Results for one of the validation tests IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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WP3.2.3 Validation of the numerical methods with data measured in projects realised by the industrial partners No actions have been undertaken yet to setup validation experiments. A working meeting is planned to discuss the setup of such experiments.
Deliverables WP3.2.1 • A test facility was designed and constructed and is almost operational. WP3.2.2 • Isothermal moisture transport is modelled within the CFD package by means of UDF’s. WP3.2.3 • No deliverables have been obtained yet.
Planning WP3.2.1 • Small-scale laboratory tests on drying and wetting of porous materials will be performed, as a validation of CFD-HAM-model in natural convection. WP3.2.2 • The next step in the development of the coupled CFD-HAM model is including the effect of heat transfer and hysteresis in the model. WP3.2.3 • A working meeting is planned to discuss the setup of these experiments.
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WP4 Towards an integrated approach Objectives The different subtasks of this work package are related very closely and the two researchers (PhD6 and PhD7) are involved in all the subtasks simultaneously. Therefore it was preferred to discuss the progress on this work package as a whole, instead of differentiating between different subtasks. The main objective of WP4 is the generation of a prototype software environment that will enable an integral approach of all relevant heat, air and moisture transfer processes of a building. This prototype environment will be based on externally run-time coupled distribution applications, i.e. different software packages will run in parallel and exchange simulation results at appropriate time intervals throughout the simulation period. The goal of WP4 is twofold: (1) to use the prototype for increasing our knowledge regarding the modelling and simulation aspects; (2) to use the prototype for solving real-world building related HAM-problems in order to demonstrate the practical application and benefits of this approach. This work package consists of 3 subtasks: WP4.1 The development of a prototype software environment is envisaged. ESP-r is used as starting point to develop an integrated system comprising run-time coupled distributed applications. Existing models and models developed in WP1-3 will be coupled to ESP-r, for which already some preliminary external coupling features have been developed. ESP-r itself will act as overall controller and integrator. WP4.2 The development of a coupling necessity decision procedure (CNDP) is required, which refers to identifying for which practical cases and circumstances which level of integrated software is needed. In addition, guidelines for selection of the proper spatial and temporal resolutions have to be provided. WP4.3 Validation and verification will be conducted to validate the developed integrated model and the coupling necessity decision procedure.
Description of work A literature study was necessary since developing an integrated approach for the three physical domains (heat, air and moisture) and the three geometrical domains (outdoor environment, building envelope, indoor environment) requires knowledge of the state-of-theart in the relevant research areas in building physics. In addition, knowledge of the computational aspects of software coupling is required. A considerable amount of time and effort has been devoted to the literature study on: • Wind flow around buildings • Wind pressure distributions on building façades • Wind-driven rain impingement on building façades • Surface heat and mass transfer • Combined heat and moisture transfer in porous building materials • Indoor air flow and air flow networks • Computational Fluid Dynamics • Building Physics software and Inter Process Communication (IPC)
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It included attending the 3rd International Building Physics Summer Course in Leuven (June 11-29, 2007) and attending the 12th Symposium for Building Physics (Technische Universität Dresden, Germany, March 2007). Moreover a software study was performed. As ESP-r is used as starting point to develop the integrated approach, and Fluent and HAMFEM will be used as supporting software packages, the following aspects have been studied: • ESP-r software and source code • Low programming level Fortran 77 Libraries used by ESP-r • UNIX operational system and its script language (shell programming) • Fluent software and its automation using UDFs (user-defined functions) and journals • Introduction to HAMFEM software and source code The study included the attendance of a specialised ESP-r workshop at Strathclyde University (Glasgow, UK, February 2007). A framework for each of the subtasks in WP4 has been developed. It includes definitions and classifications to assist in the execution of the subtasks. Examples include: • Coupling definitions and terminology • Definition of geometrical and physical domains • Classification of physical processes into the geometrical and physical domain matrix • Classification of variables into primary variables, secondary variables and performance indicators. • Definition of exchange variables (= variables to be exchanged between the different software packages – modules and work packages). Based on the framework definition, the integration of WP1-3 into WP4 has been initiated by a WP4 workshop held in Leuven on May 21st, 2007. The workshop has led to agreements on the characteristics, type and format of data to be exchanged between WP1-3 and WP4. Additional integration initiatives included: • Introduction to HAMFEM software and source code by WP1 and WP2 members. • Introduction into Fluent and HAMFEM software during the Building Physics Summer Course. Prototype software was developed and first case studies were performed: • Development of “prototype 1” for run-time coupling of ESP-r and Fluent for thermal indoor forced and natural convection. In this prototype, Fluent calculates and provides convective heat transfer coefficients for the interior building surfaces (CHTCINT) to ESP-r, based on the air and surface temperatures provided by ESP-r. • Development of “prototype 2a” for decoupled simulation using ESP-r and Fluent concerning external heat transfer coefficients. CFD provides the values of the constants in empirical relations for each surface CHTCEXT, which are subsequently used by ESP-r. This prototype currently only considers forced convection. • Development of “prototype 2b” for decoupled simulation using ESP-r and Fluent concerning wind pressure coefficients. The pressure coefficients are obtained by CFD simulations and transferred to ESP-r as a boundary condition for air infiltration and exfiltration. • Case studies have been conducted with prototype 1, 2a and 2b. The next steps include improving the quality of the data that is exchanged (in collaboration with other work
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•
packages), development of the CNDP for these prototypes, and the development of “prototype 3” for run-time coupling of ESP-r and HAMFEM. Documentation about implementation of the three prototypes has been written for future use.
The procedure for developing the coupling necessity decision procedure for the run-time coupling of ESP-r (outside, envelope, inside) and Fluent (inside) has been set and the work has been started. The CNDP is being developed for both natural and forced convection. Validation and verification are performed by using experiments from literature and by intermodel comparison. The focus is especially on the latter part, where some identical and generic cases are being studied and compared: • Coupled ESP-r - Fluent versus single Fluent • Coupled ESP-r – Fluent versus single ESP-r In a later stage, validation and verification simulations of the integrated model and the CNDP will be performed.
Deliverables •
•
Software development o Prototype 1. Enables the run-time coupling of ESP-r and Fluent to improve the calculation of thermal indoor natural and forced convection. o Prototype 2a. Enables the decoupled simulation with ESP-r and Fluent to improve the calculation of heat convection phenomena at the external building surface for forced convection (wind). More detailed exterior convective heat transfer coefficients than previously available are incorporated. o Prototype 2b. Enables the decoupled simulation with ESP-r and Fluent to improve the evaluation of air infiltration and exfiltration by more detailed pressure coefficient data than previously available. o Well-documented written procedures for the implementation of those prototypes, to be used by other partners in the project, or by the consultancy/software industry as future users of the software. Presentations o Monthly public PhD presentations are organised at the home university (TU Eindhoven) to provide information concerning the WP4 activities to the academic and industrial community. o Two presentations on WP4 were held at the International PhD Symposium on Building Performance Simulation (May 2007) at the Technische Universiteit Eindhoven. o Presentations will be held at at least two international conferences in the course of 2008.
Planning • • •
Prototype 1 and 2 will be further enhanced and improved and an inter-model comparison is planned. Prototype 3 will be developed for a 1D coupling of ESP-r and HAMFEM. Several journal papers are in preparation (from which conference papers will be distilled): o An overview of the implementation of pressure coefficient data in building energy simulation software
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o On the importance of detailed pressure coefficient data in building energy simulations o An overview of exterior and interior convective heat transfer coefficients in building energy simulation software o On the required level of detail for exterior convective heat transfer coefficients in building energy simulations
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WP5.1 Strategic and integrated planning of research activities Objectives The main objective of this subtask is the strategic and integrated planning of research activities. Within the scope of the Intelligence Network, it is foreseen to set up a committee which will have as duties: (1) to identify priority themes for basic research, applied research and dissemination activities; (2) to set up strategic planning meetings with representatives of leading Flemish industries and/or industrial associations to identify the priorities for future research; (3) to evaluate the progress and outcome of research projects and to plan the required dissemination strategies; (4) to set up a electronic project centre for use by the network members and related organisations.
Description of work Structured collaboration During this first year, there have been several formal and informal discussions about the possibilities for a structured collaboration between the present partners and on longer terms with other partners. On the short and medium term, it seems preferable to start up a more structured collaboration without a specific legal structure (e.g. legal status of non-profit association) in order to promote common activities. If practice proves that there is a need for, one might consider in a later phase a more formal collaboration. One of the challenges for a structured collaboration is the achievement of an intelligent balance between collaboration and competition. In certain cases, potential customers have the choice between one of the network partners without the need to involve them all. Moreover, some studies have a confidential nature. During this first year, the following proposals/collaborations were discussed between several partners: • Project on ‘after-insulation’ : proposal submitted by UGent and BBRI • Assessment of innovative systems in the EPB context : active collaboration between BBRI, UGent en K.U.Leuven • IWT Project on thermal bridges (already started before start of the SBO project): active collaboration between Sint Lucas, UGent, K.U.Leuven, Physibel and BBRI. Brainstorming on projects and programs The network is expected to play in the future a role in the following areas: • Brainstorming on possible common proposals in the framework of project calls. In the framework of project calls (IWT, EC, …), it might be efficient to have brainstorming meetings whereby possible projects with common participation are discussed. This can take different forms, e.g.: o Substantial involvement of several partners in the proposal (with other partners if needed); o Proposals whereby only 1 or 2 partners are heavily involved but whereby other partners have a supportive role (e.g. as part of advisory group or dissemination partner) • Brainstorming on priorities. Another area of brainstorming is more pro-active, whereby suggestions are formulated for future priorities, project calls. IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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Communication and dissemination In order to facilitate communication between the partners and with the external building community, a first website has been set up by K.U.Leuven (www.kuleuven.be/bwf - click on right hand side on ‘SBO project’). For private part of website, the user name and password can be obtained from K.U.Leuven. An envisaged new function on the website is to make use of the Google Custom search engine (see Appendix A and B). Training as a mean of disseminating the results of the structured collaboration CFD - Workshop CFD is becoming increasingly operational for use in daily practice. In order to show the potential of CFD, a workshop is organised in the framework of the SBO project and will be held on September 20th, 2007 (Figure 17). The focus is clearly on practitioners. Therefore, it is organised in collaboration with KVIV, the Flemish Royal Engineering Society and with ATIC, the technical association of HVAC specialists. The members of the SBO project and of the steering committee can attend the workshop free of charge.
Figure 17: CFD workshop
Post-graduate course There clearly is a need for a more advanced course on heat, air and moisture transfer in buildings. As indicated in the proposal, there is the idea of a higher course ‘Heat, air and moisture transfer: an integrated approach’. This course is organised in collaboration with the Technical Institute of the KVIV, which is a very efficient forum to disseminate results in Flanders and the Netherlands. The aim is a course at the level of existing course on acoustics (‘hogere cursus akoestiek’), organised on a regular base. Discussions were held about the content of the course and about the aims in order not to interfere with existing initiatives such as the International Building Physics Summer Course (K.U.Leuven, UGent and TU/e) and other KVIV courses) and to define the target groups.
Deliverables • •
A TETRA-project ‘Naïsolatie’ is obtained and several partners are involved in the structure for assessment of innovative systems in the EPB context. The CFD workshop is another deliverable of this WP.
Planning •
Further attention will be paid to inscribe the collaboration between all partners in future research projects and about the structuring the collaboration practically in order to deal with demands of industry. Contacts with a research board of major industrial partners will be established. If research activities fit in project calls, the consortium of partners will apply.
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• •
The information on the website will be extended and once a critical amount of content is reached, the website will be given a much more public status than a mean of internal communication. The higher course will be implemented practically and the aim is to give a series of seminars, in collaboration with other partners and coordinating organisations in order to disseminate the project results to all actors on the Flemish building market involved.
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WP5.2 Strategic implementation of testing and simulation facilities Objectives The main objective of this subtask is the strategic implementation of testing and simulation facilities. The proposed consortium has already a wide range of testing and simulation facilities. It is envisaged to make an in depth review and evaluation of these facilities in order to streamline and rationalise the future development of the facilities.
Description of work In a first phase all partners have been demanded to make up a list of the testing facilities of which they dispose. The collection of information on software tools has started up. It is the intention to have a specific filter on the software tools database as developed by DOE (http://www.eere.energy.gov/buildings/tools_directory/subjects_sub.cfm ). BBRI has worked out a concept during the past months whereby additional fields can be added in the database. The role of high quality laboratory infrastructure is of key importance for progress in basic research. The listing of the testing and simulation facilities is a useful tool for each partner to define his needs for missing infrastructure and to come to a priority list for investments in missing infrastructure. Based on the list of measurement utilities and the need for measurement utilities, the missing links useful for all partners can be defined. At present, there is in the Flemish Region and even Belgium not a high quality hot box-cold box for basic research on heat, air and mass transfer in building components. This is a major shortcoming. It is the intention to evaluate the possibilities for setting up such infrastructure. The recently adopted Hercules foundation might be a possibility for finding the required funding.
Deliverables No deliverables have been obtained yet.
Planning Due to a break of the BBRI person implied, the work is going to restart with an update of the listings above. The application for the Hercules foundation will be studied in detail and elaborated in the case a common need, which fits in their program, is defined.
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Referenties Alamdari F., Hammond G.P. (1983), Improved data correlations for buoyancy-driven convection in rooms, Building Services Engineering Research and Technology 4(3), 106-112. Awbi H.B., Hatton A. (2000), Mixed convection from heated room surfaces, Energy and Buildings 32(2), 153-166. Min T., Schutrum L., Parmelee G.V., Vouris J.D. (1956), Natural convection and radiation in a panel heated room, ASHRAE Transactions 62, 337-358. Novoselac A. (2005), Combined airflow and energy simulation program for building mechanical system design, Ph.D. thesis, Pennsylvania State University, Pennsylvania, USA. Sacré S., Janssens A., De Paepe M. (2007a), Literature review of most used empirical convective heat transfer coefficients correlations in building design, Internal report SBO project IWT-050154. Sacré S., Janssens A., De Paepe M. (2007b), Comparison of CFD-calculated CHTC’s and empirical CHTC correlations found in literature at internal building surfaces, Internal report SBO project IWT-050154. Talukdar P., James C., Simonson C.J. (2006), Annex 41 Subtask 2: Common Exercise – Modelling exercise on transient heat and moisture transfer in a bed of gypsum boards, 6th Working Meeting IEA Annex 41 - Whole Building Heat, Air and Moisture Response, Lyon, France. Talukdar P., Olutimayin S.O., Osanyintola O.F., Simonson C.J. (2007a), Transient moisture transfer between porous building material and humid air-Part-1: experimental facility and property data, International Journal of Heat and Mass Transfer, In Press, doi:10.1016/j.ijheatmasstransfer.2007.03.026. Talukdar P., Osanyintola O.F., Olutimayin S.O., Simonson C.J.(2007b), An experimental data set for benchmarking 1-D, transient heat and moisture transfer models of hygroscopic building material. Part II: Experimental, numerical and analytical data, International Journal of Heat and Mass Transfer, In Press, doi:10.1016/j.ijheatmasstransfer.2007.03.025.
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Appendices A. Website A first website has been set up by K.U.Leuven. Figure 18 to Figure 22 show a few screenshots of the website.
Figure 18: Homepage of website K.U.Leuven Laboratory of Building Physics
Figure 19 : Homepage of SBO project
Figure 20 : Overview of meetings
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Figure 21 : All meeting documents are available on the private part of the website
Figure 22 : Information on partners
B. Google custom search engine This Google tool allows building a selective search engine whereby the search results obtained by Google are filtered according to the criteria defined in the custom search. A prototype is available. It includes the websites of 34 organisations, whereby one can e.g. select to only search for pdf-documents.
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Figure 23 : Prototype of custom Google search engine
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1.2 Bijsturingen in het project Onderzoeksinhoud Er zijn tijdens het eerste projectjaar enkele bijsturingen van het project nodig gebleken wat betreft onderzoeksinhoud: • WP1.2: de eerste twee delen van deze subtask (WP1.2.1 en WP1.2.2) lopen samen met het onderzoek van een doctoraatsstudent die op een K.U.Leuven OT project werkt. Hier wordt de invloed van de contactfenomenen (bouncing, splashing en spreading) en oppervlaktefenomenen (absorptie, run-off en verdamping) op het warmte- en massatransport in de gebouwschil onderzocht. De invloed van de buitencondities, namelijk straling en wind, bleek een belangrijke invloed te hebben op de verdamping van slagregen. Toch worden deze fenomenen totnogtoe beschreven met behulp van warmte- en massaovergangscoefficienten welke meestal enkel beschikbaar zijn als een gemiddelde waarde over de gevel in functie van de windsnelheid. Daarom werd er aan de subtask 1.2 een extra onderdeel toegevoegd (WP1.2.3) waarbij de invloed van de buitencondities, zoals het complexe windveld omheen een gebouw, op de verdamping van slagregen onderzocht worden. •
WP3.1.1: Naast de experimentele analyse, leek het gebruik van CFD ook aangewezen om de luchtstroming in ruimtes te onderzoeken.
Onderzoeksbegeleiding Er zijn tijdens het eerste projectjaar geen bijsturingen van het project nodig gebleken wat betreft onderzoeksbegeleiding.
1.3 Beheer van het project Het beheer van het project bestaat uit verschillende componenten. Vooreerst is er het algemene projectbeheer dat de strategische en structurele aspecten van het project behelst. Het wetenschappelijke beheer betreft de organisatie, opvolging en evaluatie van het onderzoekswerk in de deelnemende onderzoeksgroepen en hun onderlinge communicatie. Tot slot moet ook de interactie met de gebruikersgroep beheerd worden. De ontwikkelde website is voor deze componenten een belangrijk instrument.
Algemeen projectbeheer Bij het project zijn 9 partners betrokken, waarvan 3 industriele partners: • Katholieke Universiteit Leuven, Laboratorium Bouwfysica: Staf Roels (KUL) • Universiteit Gent, vakgroep Mechanica van Stroming, Warmte en Verbranding: Erik Dick (UG-FHC), Michel De Paepe ((UG-FHC) • Universiteit Gent, vakgroep Architectuur en Stedenbouw: Arnold Janssens (UG-AS) • Technische Universiteit Eindhoven, Unit Building Physics & Systems: Jan Hensen (TU/e) • Wetenschappelijk en Technisch Centrum voor het Bouwbedrijf, departement Geotechniek en Structuren: Benoit Parmentier (WTCB-GS) • Wetenschappelijk en Technisch Centrum voor het Bouwbedrijf, departement Bouwfysica en Uitrustingen: Peter Wouters (WTCB-BU) • Daidalos Bouwfysisch Ingenieursbureau: Filip Descamps (DAI) • Physibel: Piet Houthuys (PHYS) IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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•
Ingenieursbureau Stockman: Piet Delagaye (STO)
Tussen deze negen partners werd bij het begin van het eerste projectjaar een consortium overeenkomst afgesloten, welke de contractuele aangelegenheden van de samenwerking bevestigt. Deze betreffen de achtergrondkennis van de partners, de reeds bestaande software ontwikkeld door de partners en de bescherming van de projectresultaten. Het Project Coordination Commitee (PCC) wordt gevormd door Peter Wouters(WTCB-BU), Benoit Parmentier (WTCB-GS), Piet Delagaye (STO), Jan Hensen (TU/e), Michel De Paepe (UG-FHC), Arnold Janssens (UG-AS), Filip Descamps (DAI), Piet Houthuys (PHYS), Hugo Hens (KUL) en Staf Roels (KUL), dat instaat voor het algemene beheer van het project.
Wetenschappelijk projectbeheer Binnen iedere deelnemende onderzoeksgroep neemt de werkpakketleider het dagelijkse projectbeheer op zich. Hij evalueert de wetenschappelijke vooruitgang van de onderzoekers van de onderzoeksgroep en rapporteert halfjaarlijks dienaangaande aan het PCC. Het wetenschappelijk beheer beoogt verder een goede samenwerking en uitwisseling tussen de verschillende onderzoekers. De onderzoeksresultaten en -plannen worden steeds gepresenteerd op de halfjaarlijkse vergaderingen met de stuurgroep. Daarenboven zijn er afgelopen jaar verschillende contactenmomenten geweest tussen de onderzoekers: •
• •
Er werd een werkgroep rond WP4 gehouden. Hierbij werd eerst de ESP-r software voorgesteld aan de verschillende partners. Aangezien deze software gebruik zal maken van informatie aangereikt uit de verschillende werkpakketten, werd er overlegd tussen de partners met welke programma’s ESP-r moet samenwerken en welke informatie extern kan worden aangeleverd. In het kader van koppeling tussen verschillende programma’s werd er een bijeenkomst gehouden tussen onderzoekers van WP2 en WP4. Hier werd de methodologie voor de koppeling van het programma HAMFEM met ESP-r besproken. Er werd een werkgroep gehouden rond WP5. Hierbij werden de krijtlijnen in verband met de oprichting en het statuut van InfoHAM verder uitgezet.
Gebruikersgroep projectbeheer Zie 2.2 Overzicht van de uitgevoerde valorisatieacties, oprichting en vergaderingen gebruikersgroep.
Website Zoals reeds vermeld in WP5 is er een website in ontwikkeling welke voorlopig toegankelijk is via de website van het Laboratorium Bouwfysica (http://www.kuleuven.be/bwf). Deze dient om de informatie-uitwisseling tussen de verschillende betrokkenen van het project (partners, onderzoekers, leden gebruikersgroep en externe geïnteresseerden) vlot te laten verlopen. Deze stelt het project voor en zijn deelnemende partners en bevat onder andere verslagen van de gebruikersgroep en de stuurgroep vergaderingen. Deze laatste zijn slechts selectief toegankelijk. De website maakt deel uit van de managementstrategie voor het project. Het is een efficient communicatiekanaal waarlangs agenda’s, verslagen en geplande vergaderingen kunnen doorgegeven worden. Daarenboven vormt de website een archief voor belangrijke
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projectdocumenten welke door de betrokkenen kunnen geraadpleegd worden. Er wordt slechts selectief toegang verleend aan verschillende betrokkenen tot interne documenten.
1.4 Haalbaarheid van het project Het project verloopt goed, zowel voor onderzoek als valorisatie. Bij de start van het project was er nog één onderzoeksfunctie niet ingevuld, namalijk PhD4 uit WP3.2. Het geplande werk werd evenwel gedeeltelijk uitgevoerd door andere onderzoekers van de betrokken partners. Intussen is de onderzoeksfunctie ingevuld (Marnix Vanbellegem). Voor WP3.1 verlaat een onderzoeker (Sarah Sacré) het project (PhD5). Deze functie wordt echter aansluitend ingevuld door een nieuwe onderzoeker (Kim Goethals). Alle zeven de onderzoeksfuncties zijn dus ingevuld op dit moment. De haalbaarheid van het project wordt niet in vraag gesteld. Zie 2.2 Overzicht van de uitgevoerde valoriatieacties voor een overzicht van de reeds ondernomen valorisatiereacties
1.5 Te beschermen resultaten De uit dit projectjaar resulterende software wordt nog niet publiekelijk verspreid wat bescherming nog niet noodzakelijk maakt.
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2 Utilisatieverslag 2.1 Valorisatiepotentieel: geactualiseerde visie Toepassingsgebieden Dit project heeft als doel het verenigen van verschillende onderzoeksdomeinen om zo te komen tot een geintegreerde benadering van warmte-, lucht-, en massatransport in gebouwen. Deze benadering dient in eerste instantie om kennis te verzamelen omtrent het koppelen van verschillende numerieke modellen in een geïntegreerd model. Deze integrale benadering moet leiden tot een optimalisatie van gebouwen, zowel wat betreft economische besparingen als duurzame ontwikkeling. Dit maakt dat het project verscheidene toepassingsgebieden heeft: • Bij het ontwerp en de constuctie van nieuwe hoogtechnologische gebouwen proberen de ontwerpers de gebouwrespons inzake warmte-, lucht- en vochtgedrag te voorspellen en te regelen. Hierbij kan de door het project ontwikkelde kennis bijdragen tot een inzicht in de interactie tussen onder andere HVAC systemen en de gebouwschil. • Om kleine gebouwen duurzaam en energiezuinig te maken, worden er verschillende innovatieve systemen ontwikkeld, zoals gevels met stalen of houten frames waartussen hygroscopisch bufferende materialen worden geplaatst met dampopen binnen- en buitenbekleding. Een geïntegreerde aanpak laat een gedetailleerde analyse van de duurzaamheid van deze systemen toe. • De geïntegreerde aanpak kan ook van nut zijn bij de renovatie en restauratie van het Vlaams cultureel erfgoed. Aangezien er hierbij meestal ingrijpende veranderingen worden doorgevoerd, is een goede evaluatie van de respons van het gebouw op deze nieuwe situatie van belang. Uiteraard kan dit project kan ook van nut zijn in andere toepassingsgebieden, waarvan er enkele aangehaald worden verderop in de tekst.
Valorisatie- en absorptiepotentieel Dit project heeft als doel de ontwikkeling van een geintegreerd model wat moet toelaten om het hygrothermisch gedrag van gebouwen gedetailleerd te evalueren. Er zullen verscheidene programma’s gebruikt worden op verschilllende niveaus en, afhankelijk van de toepassing, al dan niet gekoppeld. De belangrijkste zijn CFD, gebouwenergiesimulatieprogramma’s en gekoppelde warmte-, lucht- en vochttransportmodellen. Op lange termijn wordt de commerciele ontwikkeling van een geïntegreerd model beoogd. Omwille van de complexiteit van de programma’s is het wat ambitieus om deze ontwikkeling op korte termijn te zien. Deze ontwikkelingen zullen later dus vooral tot nut zijn voor studiebureaus en software ontwikkelaars. Op korte termijn is echter de verspreiding en toegankelijkheid van de opgebouwde kennis naar de bouwsector toe van belang. Dit laatste komt het utilisatiepotentieel zeker ten goede aangezien elke begunstigde de verworven kennis kan aanwenden om in zijn werkgebied vooruitgang te boeken. De strategie die hiervoor ontwikkeld werd, wordt in de volgende paragraaf besproken.
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Valorisatieplan en acties voor de verspeiding van kennis Opdat de bouwsector de ontwikkelde kennis kan aanwenden is het belangrijk dat deze kennis door de projectpartners op een duidelijke wijze overdragen. Dit is één van de hoofddoelstellingen van WP5. Om het valorisatie en absorptiepotentieel van het project te vergroten werd er een gebruikersgroep opgericht. De leden van deze gebruikersgroep hebben niet alleen als functie om de kennis over te dragen. Zij worden ook verwacht om tijdens het project feedback te geven over de resultaten. De gebruikersgroep werd samengesteld uit een zo breed mogelijk publiek uit verschillende subgroepen in de bouwnijverheid: 1) de sector van productontwikkeling en de producenten van bouwmaterialen; 2) architecten en aannemers samen met profesionele klanten; 3) ingenieursbureau’s en gebouwbeheer (building management offices); 4) de wetenschappelijke onderzoekswereld; 5) gebruikers die zich bezighouden met duurzame ontwikkeling in de bouwnijverheid. Deze opdeling in subgroepen werd gemaakt opdat de overdracht van kennis zou kunnen gerealiseerd worden op een gepaste wijze voor elke subgroep. Door middel van aangepaste sessies voor één of verschillende subgroepen kan de verworven kennis toegankelijk gemaakt worden. Een voorbeeld hiervan is de geplande CFD workshop aansluitend bij de tweede plenaire vergadering van de gebruikersgroep. Deze is vooral bedoeld om subgroepen 1, 3 en 4 aan te spreken. In het verdere verloop van het project zullen er ook sessies gehouden worden die toegankelijk zijn voor de andere subgroepen. Een ander initiatief wat moet bijdragen tot de verspreiding van de kennis van de partners is de oprichting van InfoHAM, wat zal dienen als een informatie netwerk omtrent onderzoek over warmte-, lucht- en massatransport. Daarenboven zal InfoHAM ook cursussen en lezingen organiseren, zoals reeds vermeld werd onder WP5. De goede samenwerking tussen de verschillende onderzoeksinstellingen is ook belangrijk aangezien deze zorgt voor een uitwisseling en uitbreiding van kennis en expertise in de verschillende vakgebieden. Hierbij is tevens de bijdrage van de industriele partners van groot belang.
Verdere toepassingsgebieden Aangezien dit project een integratiemethodologie zal aanreiken, kan dit in vele andere onderzoeksdomeinen ook toepassingen hebben welke evenwel niet beperkt zijn tot de bouwsector. Hieronder worden enkele mogelijke toepassingsgebieden aangehaald. Een uitgebreide beschrijving ervan kan gevonden worden in de projectaanvraag. • Optimisatie van productieprocessen voor materialen • Slagregen als een randvoorwaarde voor onderzoek in bouwfysica en aardwetenschappen • Schadeanalyse van onderdelen van het cultureel erfgoed in historische gebouwen • Optimalisatie van 3D (thermische) simulatieprogramma’s • Optimalisatie van binnenomgevingen van auto’s, vliegtuigen en treinen • Computer gestuurd ontwerp van bio-thermische processen van landbouwproducten • Optimalisatie van koeling van electronische componenten en temperatuurmanagement van PCB’s door gebruik te maken van de VLES techniek
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2.2 Overzicht van de uitgevoerde valorisatieacties Dit onderdeel geeft aan welke valorisatieacties er reeds ondernomen zijn tijdens het eerste projectjaar.
Oprichting en vergaderingen gebruikersgroep Er werd een gebruikersgroep opgericht bij de aanvraag van het project dewelke momenteel 28 leden telt: • CIR • CIR-Styfabel • Febe • IsoproC • Renson • Reynaers Aluminium • Verozo • Artex/Matexi • Brussels Office for Architecture • NAV, de Vlaamse Architectenorganisatie • Vlaamse Huisvestingsmaatschappij • Zonnige Kempen • 3E • Bureau Bouwtechniek • Cenergie bvba • Decysis bvba • Grontmij Atenco nv • Ingenium • REUS • Studiebureau R. Boydens bvba • VK Engineering • K.U.Leuven, Labo Agrarische Bouwkunde • UGent, Onderzoeksgroep Biosysteemtechniek • VITO • Centrum Duurzaam Bouwen • Dialoog vzw • Kamp C • Passiefhuis-Platform vzw • Technologisch Instituut vzw Tijdens de startvergadering (8 september 2006) werd hen het project voorgesteld: doelstellingen, strategie en onderzoeksplanning. De volgende vergadering voor de gebruikersgroep is gepland op 20 september 2007. Na elke vergadering is er ruimte voor feedback voorzien.
Publicaties in tijdschriften en presentatie op conferenties Aangezien het tweede projectjaar nog maar net is ingegaan, zijn nog geen papers aanvaard of ingediend voor publicatie in een internationaal tijdschrift.
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De projectresultaten reeds voorgesteld op meerdere internationale conferenties, waarvan de desbetreffende papers zijn opgenomen in de proceedings: Proceedings gepubliceerd Abuku M., Blocken B., Carmeliet J., Roels S. (2006), A status report of wind-driven rain research at the Laboratory of Building Physics, K.U.Leuven, Proceedings of the Fourth International Symposium on Computational Wind Engineering, Yokohama, Japan. Abuku M., Janssen H., Roels S. (2007), Numerical simulation of absorption and evaporation of wind-driven rain at building façades, Proceedings of the 12th Symposium for Building Physics, Dresden, Germany, 588-595. Steeman H., Janssens A., De Paepe M. (2007), About the use of the heat and mass analogy in building simulation, 12th Symposium for Building Physics, Dresden, Germany, 455-462. Steeman H., Willockx A., Caniere H., T’joen C., Janssens A., De Paepe M. (2007), Numerical study of the accuracy of the heat and mass analogy for mixed convection in enclosures, Proceedings of the Fifth International Conference on Heat Transfer, Fluid Mechanics & Thermodynamics, Sun City, South-Afrika. Steeman H., T’joen C., Willockx A., De Paepe M., Janssens A. (2007), A CFD modelling of HAM transport in buildings: Boundary conditions, Proceedings of the Third International Building Physics Conference, Montréal, Canada, 535-542. ingediend Breesch H., Janssens A. (2007), Reliable design of natural night ventilation using building simulation, submitted to the Thermal Performance of the Exterior Envelopes of Whole Buildings X International Conference, Clearwater, Florida.
Interne rapporten en meetings Publicaties in internationale tijdschriften en voorstellingen op internationale conferenties worden in de loop van het project aangevuld met interne technische rapporten en software handleidingen, om de uitwisseling van kennis tussen de verschillende onderzoekers te vergemakkelijken. Deze rapporten zullen ook ter beschikking gesteld worden aan de gebruikersgroep. Volgende rapporten zijn reeds beschikbaar: Sacré S., Janssens A., De Paepe M. (2007a), Literature review of most used empirical convective heat transfer coefficients correlations in building design, Internal report SBO project IWT-050154. Sacré S., Janssens A., De Paepe M. (2007b), Comparison of CFD-calculated CHTC’s and empirical CHTC correlations found in literature at internal building surfaces, Internal report SBO project IWT-050154. Abuku M., Janssen H., Blocken B., Carmeliet J., Roels S.(2006), Wind-driven rain load on building enclosures - towards the reliable prediction of absorption and evaporation, Contribution to the IEA Annex 41 Whole Building Heat, Air and IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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Moisture Response, Subtask 3 – Boundary condition, International Report A41-T3-B06-7. Abuku M., Janssen H., Roels S. (2007), Impact of wind-driven rain on mould growth and indoor climate, Contribution to the IEA Annex 41 Whole Building Heat, Air and Moisture Response, Subtask 4 - Long term performance and technology transfer, International Report A41-T4-B-07-2. Daarenboven zijn er ook reeds twee stuurgroepvergaderingen geweest (5 februari en 10 september 2007) waar alle onderzoekers hun resultaten voorstelden. Daarna volgde een collectieve bespreking van de verdere onderzoeksstrategie en planning.
Cursussen, workshops, conferenties en aanverwante activiteiten De uit het onderzoeksprogramma voortvloeiende kennis en expertise worden bekendgemaakt op studiedagen, cursussen, conferenties en workshops gericht naar de belanghebbende actoren uit zowel de bouwsector als de wetenschappelijke wereld. Daarenboven wordt de verworven kennis reeds aangewend in aanverwante onderzoeksprojecten en in industriële opdrachten. Hier volgt een overzicht van deze activiteiten: Cursussen en workshops • Wetenschappelijke coördinatie postacademische opleiding ‘Energietechniek in Gebouwen’(Janssens A. en De Paepe M.), Instituut voor Permanente Vorming UGent (IVPV) en TI-KVIV. o Eerste editie: oktober 2006 – maart 2007 (11 lesdagen, 70 deelnemers), Antwerpen-Gent. o Tweede editie: oktober 2007-april 2008 (12 lesdagen) • Maandelijkse PhD “progress” meetings aan Technische Universiteit Eindhoven. Meetings georganiseerd in de tweede helft van elke maand, waarop academische en industriële partners aanwezig zijn om informatie te bekomen over de nieuwe ontwikkelingen in WP4. • PhD Summer Course: Heat and Mass Transport in Building Materials, Components and Whole Buildings: From Fundamentals to New Advances (Hensen J., Blocken B., De Paepe M.), Leuven, 11-29 juni, 2007. Conferenties en symposia • PhD Symposium Building Performance Simulation (mei 2007). Symposium georganiseerd door Jan Hensen als hoofd van de “building performance simulation” groep aan de TU/e voor kennisuitwisseling tussen industriële partners enerzijds en de TU/e en de “Czech Technical University” in Praag anderzijds. • Deelname aan de IEA Annex 41 Whole Building Heat, Air and Moisture Response (MOIST-ENG) met presentatie van verschillende tussenresultaten op de meeting als invited en free papers en deelname common exercises in HAM-modeling. (Meeting 25-27 october, 2006 Lyon, Frankrijk en 16-18 april, 2007 Florianopolis, Brazilië). M. De Paepe en A. Janssens zijn co-editor voor het eindrapport voor het deel HAMmodelling (Subtask 1) en boundary conditions (Subtask 3). S. Roels is editor voor het eindrapport over ‘Experimental analysis of moisture buffering’ (Subtask 2). Aanverwante onderzoeksprojecten ter ondersteuning van of resulterend uit het project • BOF-basisuitrusting 2006, ‘Klimaatkamer voor analyse van warmte- vocht en luchttransport in lokalen’, i.s.m. UGent IR03 (De Paepe M.), 40 000,00 € (uitrusting). IWT SBO project 050154 – Heat, air and moisture performance engineering - A whole building approach Eerste jaarlijks rapport
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•
IWT Tetra 2007. ‘Na-Isolatie van Bestaande spouwmuren: analyse van kwaliteit en geschiktheid van materialen en uitvoeringstechnieken.’ UGent Architectuur en Stedenbouw i.s.m. WenK St-Lucas Architectuur, WTCB en CIR, 1/10/200730/9/2009.
Varia • Bezoek aan de University of Strathclyde in Glasgow. Kennisuitwisseling over ESP-r en WP4 met ESP-r softwareontwikkelaars en -specialisten. • Gebruik van de ontwikkelde modellen in een industriële opdracht: Survey van droogprocessen en energetische optimalisatie van een bestaand droogproces. Emerson & Cuming Microwave Product NV, Nijverheidsstraat 7A, 2260 Westerlo, Ugent contract nr0613
Opstellen jaarverslagen Het wetenschappelijk-technisch deel van het jaarverslag vormt een belangrijk onderdeel in de kennisoverdracht naar de gebruikersgroep omtrent de behaalde projectresultaten.
Ontwikkeling website Er werd een voorlopige website ontwikkeld welke verder uitgebreid zal worden tijdens het volgende projectjaar. Deze website dient niet alleen om de interne werking en uitwisseling van verslagen en voorstellingen te vergemakkelijken. Externe geïnteresseerden kunnen er ook algemene informatie terugvinden over het project.
2.3 Bescherming projectresultaten De in dit project ontwikkelde software wordt nog niet publiekelijk verspreid wat bescherming nog niet noodzakelijk maakt. Acties ter bescherming van de projectresultaten zijn daarom ook nog niet ondernomen.
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3 Financieel verslag 3.1 Prestatietabel De prestatietabellen voor de negen partners voor het projectjaar 2006-2007 worden bezorgd aan het IWT door K.U.Leuven LRD.
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3.2 Prognose voor komend projectjaar De inzet van mensen voor het projectjaar 2007-2008 wordt als volgt ingeschat. Partner KUL UG-FHC UG-AS WTCB-GS WTCB-BU TUE PHYS DAI STO
Medewerker Thijs Defraeye Joachim Verhaegen Marnix Vanbellegem Demir-Ali Köse Kim Goethals Benoit Parmentier Luc Tisseghem Peter Wouters Mohammad Mirsadeghi Daniel Costola Piet Houthuys Piet Standaert Filip Descamps Piet Delagaye Stefanie Sallet Bart Marivoet
barema bursaal wet.mw. bursaal bursaal bursaal ir. tech. bursaal bursaal dr.ir. dr.ir. dr.ir.-arch. ir. ir. student
maanden 12 12 12 12 12 5 3 ntb 12 12 1 2 ntb ntb ntb ntb
periode 01/09/07-31/08/08 01/09/07-31/08/08 01/09/07-31/08/08 01/09/07-31/08/08 01/09/07-31/08/08
01/09/07-31/08/08 01/09/07-31/08/08
De inzet van middelen wordt niet ingeschat, er zijn geen grote onderaannemingen of aankopen gepland.
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3.3 Financiële verantwoording De kostenstaten voor de negen partners voor het eerste projectjaar worden bezorgd aan het IWT door K.U.Leuven LRD. Hierbij dienen enkele opmerkingen gemaakt te worden: •
Bij opstart van het project is het onmogelijk gebleken de voorziene twee doctoraatsbursalen aan te werven voor WP 1.1 en WP 3.2. Per 01/09/2006 is DemirAli Köse in dienst gekomen. Hij heeft 12 maanden in de werkperiode gewerkt. De tweede bursaal is in dienst getreden op 01/08/2007 en heeft dus 1 maand in de beschouwde werkperiode gewerkt. Om de afwezigheid van de tweede bursaal te compenseren is een persoon ingezet waarvan de loonlast niet op het project komt: Hendrik-Jan Steeman. Hij heeft 4 maand gepresteerd op het project. Doordat er een moeilijkheid geweest is om de twee voorziene bursalen aan te werven bij de startdatum, is de uitgave voor personeel minder groot dan voorzien in het budget. De uitgaven voor werking zijn daarentegen groter dan voorzien in het budget. Dit komt omdat een begininvestering is uitgevoerd in computerinfrastructuur. Het onevenwicht zal in de volgende projectjaren weggewerkt worden.
•
Bij opstart van het project is het onmogelijk gebleken de voorziene twee doctoraatsbursalen aan te werven voor WP4. De betrokken personen zijn intussen reeds aangeworven en hebben beiden 10 maanden gepresteerd in de beschouwde werkperiode.
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