Study of the Effect of Exhaust Gases from a Sample Vehicle on the Drag Coefficient

Authors

1 MSc., Aerospace Engineering, Ferdowsi University of Mashhad, Mashhad, Iran

2 Assoc. Prof., Aerospace Eng., Embry Riddle Aeronautical University, FL, USA

3 Prof., Mechanical Engineering, Ferdowsi University of Mashhad, Mashhad, Iran

Abstract

This research delves into the practical implications of the effect of exhaust gases on the wake region of an Audi car, which includes vortices and separated flowing from its surface. The findings could potentially inform future vehicle design and performance strategies. The car model's rear configuration is akin to the standard DrivAer Estateback car, which the Aerodynamics Institute of the Technical University of Munich has modeled. The SST k-ω turbulence model is selected for simulation using computational fluid dynamics, considering the problem's nature and the flow stability analysis. To validate the solution method, the numerical results obtained from flow simulation at a Reynolds number of 4.87×106 around the standard model are compared with the experimental results obtained from the wind tunnel. After validating the solution method, it was determined in the initial investigation that at the given Reynolds number, the drag coefficient of the Audi car with an exhaust system is 1.15 % lower than the drag coefficient of the car without an exhaust system. Furthermore, the effects of increasing the vehicle speed, the angle of the exhaust pipe outlet, and finally, the presence of an exhaust on one side of it on the value of the drag coefficient are examined.

Keywords

Main Subjects

References

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Journal of Solid and Fluid Mechanics
Volume 14, Issue 5
November and December 2024
Pages 39-52

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