TAKARIR
Computational Fluid Dynamic : Komputasi Aliran Fluida Dinamik Software
: Perangkat lunak
Drag Force
: Gaya hambat
Lift Force
: Gaya angkat
Angel Attack
: Sudut serang
Wind Tunnel
: Terowongan angin
Center of Gravity
: Pusat massa
Density
: Kerapatan udara
Solid
: Padat atau pejal
Area frontal
: Daerah proyeksi
Continum
: Memiliki jumlah sel tak terhingga
Strimeline
: Garis arus
Vertex
: Titik
Edge
: Garis atau kurva yang setidaknya dibangun oleh satu vertex
Face
: Bidang (tidak selalu datar / planar yang dibatasi setidaknya oleh satu edge) kecuali untuk bola
Meshing
: Bidang atau volume yang diisi oleh fluida, dibagi menjadi sel-sel kecil
Turbulance
: Suatu aliran udara yang mengalir melalui benda, di mana lapisan-lapisan udara yang terbentuk tidak rata dan arahnya berputar membentuk pusaran
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DAFTAR ISI
HALAMAN JUDUL ....................................................................................
i
LEMBAR PENGESAHAN DOSEN PEMBIMBING ................................
ii
LEMBAR PENGESAHAN DOSEN PENGUJI ..........................................
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HALAMAN PERSEMBAHAN ...................................................................
iv
HALAMAN MOTTO ..................................................................................
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KATA PENGANTAR .................................................................................. vii ABSTRAKSI ................................................................................................
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TAKARIR ....................................................................................................
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DAFTAR ISI ................................................................................................
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DAFTAR TABEL ........................................................................................ xiv DAFTAR GAMBAR .................................................................................... xv
BAB I
PENDAHULUAN 1.1 Latar Belakang ........................................................................
1
1.2 Rumusan Masalah ....................................................................
1
1.3 Batasan Masalah .....................................................................
2
1.4 Tujuan .....................................................................................
2
1.5 Manfaat Penelitian ..................................................................
2
1.6 Sistematika Penulisan ..............................................................
2
BAB II LANDASAN TEORI 2.1 Kanopi ....................................................................................
4
2.2 Konsep Kanopi.........................................................................
4
2.3 Karakteristik aliran melewati sebuah benda .............................
4
2.4 Gaya Hambat (Drag Force) .....................................................
5
2.5 Gaya Angkat (Lift Force) ........................................................
7
2.6 Momen ....................................................................................
7
2.7 Properti Udara (Gas) ...............................................................
9
2.7.1 Suhu (Temperature) ........................................................
9
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2.7.2 Kerapatan (Density) .......................................................
9
2.8 Jenis-Jenis Aliran .................................................................... 10 2.8.1 Aliran Inviscid ............................................................... 10 2.8.2 Aliran Viscous ................................................................ 11 2.9 Metode Komputansi ................................................................. 12
BAB III METODOLOGI PENELITIAN 3.1 Konsep ..................................................................................... 13 3.2 Jenis dan Sumber Data ............................................................. 13 3.2.1 Data Primer ................................................................... 13 3.2.2 Data Sekunder ............................................................... 14 3.3 Metode Pengumpulan Data ...................................................... 14 3.3.1 Subyek Penelitian .......................................................... 14 3.3.2 Peralatan yang Digunakan .............................................. 14 3.4 Pengujian CFD (Computatinal Fluid Dynamics) ..................... 15 3.5 Metode Pengolahan Data ......................................................... 18 3.5.1 Prosedur Pengolahan Data .............................................. 19 3.6 Metode Analisis ...................................................................... 19 3.6.1 Merencanakan Analisis CFD ......................................... 20 3.6.2 Langkah Penyelesaian Masalah ...................................... 20
BAB IV PENGUMPULAN DAN PENGOLAHAN DATA 4.1 Proses Pengujian ..................................................................... 23 4.1.1 Proses Pembuatan Desain ............................................... 23 4.2 Langkah-Langkah Pengujian CFD ........................................... 24 4.2.1 Mencari pusat massa dengan menggunakan software Inventor 2009 .................................................................. 24 4.2.2 Import File CAD ............................................................. 25 4.2.3 Merubah pusat massa ...................................................... 26 4.2.4 Membuat batasan benda uji ............................................. 27 4.2.5 Perbaikan desain ............................................................. 28
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4.2.6 Pembuatan mesh ............................................................. 28 4.2.7 Menentukan kondisi batas aliran fluida ........................... 30 4.3 Pengujian CFD (Computational Fluid Dynamics) ................... 30 4.4 Hasil pengujian ....................................................................... 31 4.4.1 Pressure ......................................................................... 32 4.4.2 Velocity .......................................................................... 34 4.4.3 Turbulence ..................................................................... 36
BAB V
ANALISA DAN PEMBAHASAN 5.1 Perhitungan Gaya Hambat dan Gaya Angkat pada Kanopi ...... 37 5.2 Analisa Gaya Hambat............................................................... 39 5.3 Analisa Gaya Angkat .............................................................. 40 5.4 Analisa Momen ...................................................................... 40 5.5 Analisa Turbulance ................................................................. 41 5.6 Analisa Hasil Pengujian .......................................................... 42 5.7 Perbandingan Pengujian .......................................................... 43 5.7.1 Turbulence .................................................................... 44 5.7.2 Perbandingan streamline ................................................. 45
BAB VI PENUTUP 6.1 Kesimpulan ............................................................................. 46 6.2 Saran ....................................................................................... 46
DAFTAR PUSTAKA ................................................................................... 47 LAMPIRAN ................................................................................................. 48
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DAFTAR TABEL
Tabel 2.1 Koefisien hambat aerodinamis untuk beberapa kendaraan .............. 5 Tabel 4.1 Hasil Pengujian CFD ..................................................................... 28 Tabel 5.1 Hasil Perhitungan gaya Drag (FD) dan gaya Lift (FL). .................... 37 Tabel 5.2 Perbandingan hasil pengujian gaya Drag (FD) dan gaya Lift (FL) pada kanopi berlubang dan tidak berlubang..................................... 44
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DAFTAR GAMBAR
Gambar 2.1 Sepeda motor berkanopi .............................................................. 4 Gambar 2.2 Foto dari visualisai melewati sebuah airfoil ................................. 5 Gambar 2.3 Koefisien gaya hambat benda 3 dimensi ...................................... 6 Gambar 2.4 Sudut serang angin sekala tegak dan mendatar ............................ 8 Gambar 2.5 Momen aerodinamika .................................................................. 9 Gambar 2.6 Grafik Moody ........................................................................... 11 Gambar 2.7 Struktur komponen pada Fluent ................................................. 12 Gambar 3.1 Desain 2D ................................................................................. 15 Gambar 3.2 Desain 3D ................................................................................. 16 Gambar 3.3 Ukuran kanopi ........................................................................... 16 Gambar 3.4 Pembuatan batas benda uji ........................................................ 17 Gambar 3.5 Pembuatan mesh dan penentuan aliran fluida .............................. 17 Gambar 3.6 Simulasi aliran udara .................................................................. 18 Gambar 3.7 Hasil pengujian ......................................................................... 18 Gambar 3.8 Diagram alir penelitian ............................................................... 19 Gambar 3.9 Diagram alir prosedur simulasi ................................................... 22 Gambar 4.1 (a) Kanopi model, (b) Kanopi desain CAD, (c) Kanopi mesh, (d) Kanopi CFD ........................................................................ 24 Gambar 4.2 Pusat massa kanopi ................................................................... 25 Gambar 4.3 Proses import file CAD pada software Gambit ............................ 25 Gambar 4.4 Titik 0,0 sebelum dipindahkan ke titik pusat massa .................... 26 Gambar 4.5 Titik 0,0 menjadi titik pusat massa ............................................. 26 Gambar 4.6 Batasan benda uji pada Wind Tunnnel ........................................ 27 Gambar 4.7 Batasan benda uji pada software Gambit .................................... 27 Gambar 4.8 (a) Sebelum proses cleanup tools, (b) Sesudah proses cleanup tools ........................................................................................... 28 Gambar 4.9 Mesh yang telah jadi pada software Gambit ............................... 29 Gambar 4.10 Penentuan batasan aliran fluida .................................................. 30 Gambar 4.11 Simulasi aliran fluida ................................................................. 31
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Gambar 4.12 Countur coefisien pressure ......................................................... 32 Gambar 4.13 Countur static pressure ............................................................ 33 Gambar 4.14 Countur dynamic pressure ........................................................ 33 Gambar 4.15 Countur total pressure .............................................................. 34 Gambar 4.16 Countur magnitude velocity ...................................................... 34 Gambar 4.17 Countur X velocity ..................................................................... 35 Gambar 4.18 Countur Y velocity .................................................................... 35 Gambar 4.19 Countur Z velocity .................................................................... 35 Gambar 4.20 Countur intensity turbulence .................................................... 36 Gambar 4.21 Countur kinetic energy turbulence ............................................ 36 Gambar 5.1 Grafik gaya hambat dan gaya angkat .......................................... 35 Gambar 5.2 Mencari luas area frontal ........................................................... 35 Gambar 5.3 Permukaan yg tidak rata ............................................................. 36 Gambar 5.4 Bagian belakang menahan aliran fluida ...................................... 37 Gambar 5.5 Area terjadinya turbulence ......................................................... 38 Gambar 5.6 Kanopi sebelum penambahan lubang pada bagian belakang ....... 39 Gambar 5.7 Perubahan desain kanopi pada bagian belakang .......................... 40 Gambar 5.8 Countur intensity turbulence ...................................................... 41 Gambar 5.9 Aliran turbulence terjadi pada kanopi tanpa lubang .................... 42 Gambar 5.10 Tidak terjadi Aliran turbulence pada kanopi berlubang ............... 43
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