Investigation of the Effect of Side Mirror Forms on Ahmed Body with CFD Method

Abstract

The purpose of this study is to investigate the air resistance effect of different side mir-ror models on automobiles. The Ahmed Body model with 250 slant angle is taken as ref-erence for use as automobile geometry. Ahmed body is a simplified geometry model used for aerodynamic analysis of land vehicles. Side mirror models with the same front projection area were modeled using Solidworks. CFD simulation was performed with ANSYS Fluent 19.2. Realizable k-ε model is used as turbulence model and pressure-based type is used as solver type. In this study, the mesh quality was checked in terms of skewness and showed conformity. CD value obtained by numerical analysis is compati-ble with experimental data. Then, a comparison was made by adding side mirrors to the Ahmed Body model. As a result of the analysis, the display of the velocity and pressure distribution caused by the change of form around the mirror models and total CD values were determined.

Keywords

• Ahmed body
• Drag coefficient
• CFD
• k-Epsilon realizable model
• Side mirror

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