Assessment of conventional and air-jet wheel deflectors for drag reduction of the DrivAer model  

作　　者：Kaloki L.Nabutola Sandra K.S.Boetcher 

机构地区：[1]Department of Mechanical Engineering,Embry-Riddle Aeronautical University,Daytona Beach,FL,USA

出　　处：《Advances in Aerodynamics》2021年第1期512-539,共28页空气动力学进展（英文）

摘　　要：Aerodynamic drag is a large resistance force to vehicle motion,particularly at highway speeds.Conventional wheel deflectors were designed to reduce the wheel drag and,consequently,the overall vehicle drag;however,they may actually be detrimental to vehicle aerodynamics in modern designs.In the present study,computational fluid dynamics simulations were conducted on the notchback DrivAer model-a simplified,yet realistic,open-source vehicle model that incorporates features of a modern passenger vehicle.Conventional and air-jet wheel deflectors upstream of the front wheels were introduced to assess the effect of underbody-flow deflection on the vehicle drag.Conventional wheel-deflector designs with varying heights were observed and compared to 45◦and 90◦air-jet wheel deflectors.The conventional wheel deflectors reduced wheel drag but resulted in an overall drag increase of up to 10%.For the cases studied,the 90◦air jet did not reduce the overall drag compared to the baseline case;the 45◦air jet presented drag benefits of up to 1.5%at 35 m/s and above.Compared to conventional wheel deflectors,air-jet wheel deflectors have the potential to reduce vehicle drag to a greater extent and present the benefit of being turned off at lower speeds when flow deflection is undesirable,thus improving efficiency and reducing emissions.

关 键 词：Vehicle aerodynamics Wheel and wheelhouse aerodynamics Automotive Active flow control Passive flow control DrivAer 

分 类 号：O35[理学—流体力学]