The Study Of The Aerodynamic Characteristics Of SUV

The aerodynamic characteristics of an automobile are important factors that affect the overall performance of a vehicle.The car's aerodynamic characteristics include two aspects: first,the resistance characteristics of automobile aerodynamic,automobile aerodynamic drag performance directly affects the fuel economy and the operating stability;Secondly,the characteristics of automobile aerodynamic noise,The aerodynamic noise has a very important influence on the riding comfort of the driver and passengers,and also relates to the safety of the vehicle.The aerodynamic drag coefficient and aerodynamic noise of a SUV are analyzed by simulation.Aerodynamic drag coefficients of a certain SUV,aerodynamic noise in the outfield and infield are obtained by simulation.At the same time,the reliability of the simulation is verified by wind tunnel test and real vehicle road test.The wheel cavity space has a direct influence on the vehicle drag coefficient,and the drag coefficient of the whole vehicle can be reduced by reducing the space of the wheel cavity.The opening area of wheel spokes is the main factor affecting the car's wind resistance.By calculating the drag coefficient after installing the air curtain,it is found that the air curtain can reduce its drag coefficient and improve its aerodynamic resistance performance,and the reasonable form of air curtain has a great influence on the coefficient of drag of the whole vehicle.Based on the calculation results of external sound source,the rearview mirror is modified to reduce the sound pressure level of the external aerodynamic noise effectively.By means of APE method,the turbulent pressure pulsation and the acoustic pressure fluctuation produced by the rearview mirror on the side window are separated.It is found that the turbulent pressure fluctuation produces low and middle frequency aerodynamic noise,while the acoustic pressure fluctuation produces medium and high frequency aerodynamic noise.The sound pressure level of aerodynamic noise in the driver's ear is obtained by using the statistical energy method.The simulation is performed without outside rearview mirrors,the rearview mirror mainly affects the aerodynamic noise at the frequency of about 4000 Hz.