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Evaluation and Optimization of the Aerodynamic Noise Reduction of Vehicle Side View Mirrors: Experimental and Numerical Study

Mohammad Gohari, Rasoul Norozi, Abolfazl Hajizadeh Aghdam

Abstract


Automobile passengers are usually sensitive to the noises generated by the engine and vehicle body. One of the noise sources is the generated turbulent flow around the Vehicle Side View Mirror (VSVM) and around the A-pillar, producing fluctuating pressure. Unwanted noise is a result of fluctuating pressure around the car's body. Modification of the geometry of the vehicle body may affect the generated noise by turbulent flow. In this paper, the original side view mirror of a small sedan car named Tiba was aimed at geometry modification to decrease airborne noise. The mirror was assessed by CFD simulation and an outdoor test. Road tests were applied at three forward speeds (80, 100, and 120 km/h) to measure the sound level generated by the vehicle's side mirrors. Then, the geometry of VSVM was modified to diminish the sound pressure level of that based on decreasing turbulent flow and fluctuating pressure around the side mirror. Finally, the achieved geometry was evaluated using road tests, which showed a noise reduction of 8 to 12%. Road tests were done for the modified side car mirror. It shows that a modified mirror can reduce the sound level of airborne noise. By using this suggested modified side view mirror, the risk of annoying noise may be diminished and passenger comfortability can be increased through driving.

 

Doi: 10.28991/HIJ-2022-03-01-08

Full Text: PDF


Keywords


Aerodynamic Noise; Vehicle Side View Mirror Noise; CFD; Optimization.

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Full Text: PDF

DOI: 10.28991/HIJ-2022-03-01-08

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