Adisasmita, Patrick (2026) Studi Numerik Pengaruh Variasi Sudut Kaca Belakang (Backlight Angle) terhadap Karakteristik Aliran Udara pada Model Mobil Sedan Fastback secara 3D. Other thesis, Institut Teknologi Sepuluh November.
![[thumbnail of 5007221052-Undergraduate_Thesis.pdf]](http://repository.its.ac.id/style/images/fileicons/text.png) |
Text
5007221052-Undergraduate_Thesis.pdf - Accepted Version Restricted to Repository staff only Download (8MB) | Request a copy |
Abstract
Desain aerodinamika kendaraan merupakan aspek penting dalam pengembangan kendaraan modern karena berpengaruh terhadap efisiensi energi, stabilitas, dan performa kendaraan, terutama pada kecepatan tinggi. Salah satu parameter geometri yang berpengaruh terhadap karakteristik aliran udara adalah sudut kaca belakang atau backlight angle. Penelitian ini bertujuan untuk menganalisis pengaruh variasi sudut kaca belakang terhadap karakteristik aliran udara, distribusi tekanan, pembentukan wake, serta koefisien drag dan lift pada model mobil sedan fastback secara tiga dimensi. Penelitian ini dilakukan menggunakan metode Computational Fluid Dynamics (CFD) dengan perangkat lunak ANSYS Fluent 2024 R1. Model kendaraan yang digunakan mengacu pada geometri Mercedes-Benz EQS yang disederhanakan, dengan variasi sudut kaca belakang sebesar 21,6°, 19,6°, 17,6°, dan 15,6°. Simulasi dilakukan pada Reynolds number 1,3 × 107 menggunakan pendekatan steady Reynolds-Averaged Navier-Stokes (RANS) dengan model turbulensi k-omega SST. Parameter yang dianalisis meliputi streamline, kontur kecepatan, kontur tekanan, pressure coefficient, drag coefficient, lift coefficient, dan struktur wake. Hasil menunjukkan hubungan non-monotonik antara konfigurasi upper rear-body dan performa aerodinamika. Konfigurasi 17,6° menghasilkan koefisien drag terendah sebesar 0,11397, sedangkan konfigurasi 21,6° menghasilkan nilai tertinggi sebesar 0,12452. Pressure drag menjadi komponen dominan dengan kontribusi 71,09–73,34% terhadap drag total. Konfigurasi 15,6° menghasilkan koefisien lift paling negatif sebesar −0,33888. Perbedaan performa berkaitan dengan perubahan pressure recovery, distribusi tekanan spanwise, pola streamline permukaan, dan struktur wake tiga dimensi.
=============================================================================================================================================
Vehicle aerodynamic design is an important aspect in the development of modern vehicles because it affects energy efficiency, stability, and overall vehicle performance, especially at high speed. One geometric parameter that influences airflow characteristics is the rear windshield angle or backlight angle. This study aims to analyze the effect of backlight angle variation on airflow characteristics, pressure distribution, wake formation, drag coefficient, and lift coefficient around a three-dimensional fastback sedan model. This study is conducted using Computational Fluid Dynamics (CFD) with ANSYS Fluent 2024 R1. The vehicle model is based on a simplified Mercedes-Benz EQS geometry, with four backlight angle variations of 21.6°, 19.6°, 17.6°, and 15.6°. The simulation is performed at a Reynolds number of 1.3 × 107 using a steady Reynolds-Averaged Navier-Stokes (RANS) approach with the k-omega SST turbulence model. The analyzed parameters inClude streamlines, velocity contours, pressure contours, pressure coefficient, drag coefficient, lift coefficient, and wake structure. The results showed a non-monotonic relationship between the upper rear-body configuration and aerodynamic performance. The 17.6° configuration produced the lowest drag coefficient of 0.11397, whereas the 21.6° configuration produced the highest value of 0.12452. Pressure drag was the dominant component, contributing 71.09–73.34% of the total drag. The 15.6° configuration produced the most negatif lift coefficient of −0.33888. These differences were associated with changes in pressure recovery, spanwise pressure distribution, surface-streamline patterns, and three-dimensional wake structure.
| Item Type: | Thesis (Other) |
|---|---|
| Uncontrolled Keywords: | backlight angle, CFD, drag coefficient, lift coefficient, pressure coefficient |
| Subjects: | Q Science > QC Physics > QC151 Fluid dynamics |
| Divisions: | Faculty of Industrial Technology and Systems Engineering (INDSYS) > Mechanical Engineering > 21201-(S1) Undergraduate Thesis |
| Depositing User: | Patrick Adisasmita |
| Date Deposited: | 30 Jul 2026 01:21 |
| Last Modified: | 30 Jul 2026 01:21 |
| URI: | http://repository.its.ac.id/id/eprint/140251 |
Actions (login required)
 |
View Item |