Validation of CFD Modeling and Simulation of a Simplified Automotive Model

Abstract

In the early design phase of automotive sector, the flow field around the vehicle is important in decision making on design changes. It would consume a lot of money and time for multiple prototypes development if adopt traditional testing method which is wind tunnel test. Thus, numerical method such as Computational Fluid Dynamics (CFD) simulation plays an important role here. It is very often simulation results been compared with wind tunnel data. However, with various mesh types, meshing methodology, discretization methods and different solver control options in CFD simulation, users may feel low confidence level with the generated simulation results. Thus, a robust modeling and simulation guideline which would help in accurate prediction should be developed due to the industry’s demand for accuracy when comparing CFD to wind tunnel results within short turnaround time. In this paper, a CFD modeling and simulation study was conducted on a simplified automotive model to validate with wind tunnel test results. The wind tunnel environment was reproduced in the simulation setup to include same boundary conditions. Meshing guidelines, turbulence model comparisons and also the best practice for solver setup with respect to accuracy will be presented. Overall, CFD modeling and simulation methods applied in this paper are able to validate the results from experiment accurately within small yaw ranges.

A Review of Aerodynamics Influence on Various Car Model Geometry through CFD Techniques

“…Launder and Spalding introduced the 𝑘 − 𝜀 turbulence model, which is the most commonly applied turbulence models by automotive designers due to its ease and simplicity in predicting accurate converge solution [60]. The 𝑘 − 𝜔 turbulence model also can be utilised as it has the ability to predict flow separation greater than other RANS models and it can generate good analysis performance of the pressure gradients [57].…”

Flow Structure Characteristics of the Simplified Compact Car Exposed to Crosswind Effects using CFD

“…The distance of the vehicle from the side is selected to enlarge five vehicle lengths (5L) for the both left and right of the car on the y-direction. Based on Mansor et al [22], it is critical to ensure that the flow is completely formed and capture the flow structures for the crosswind situation. The Standard 𝑘 − 𝜀 model is applied with the inlet velocity, v is setup to 30.56 m/s due to the Malaysian Institute of Road Safety Research (MIROS) [13] that affected by the topology of Asia's land.…”