Aerodynamic Studies on automobile structures

Abstract

3 Abstract: Flow over skewed steps is an interesting practical problem with wide range of applications such asaerodynamic vehicles and structures. A closed view of any automobile gives an idea that it has been derived from step pattern. Now a day's researchers are concentrating on increasing of fuel economy and minimization of noise by eliminating undesirable drag forces and aerodynamic instabilities particularly in high speed vehicles. Fuel economy is mainly depends on induced drag which is a dependent of step inclination angle. This study investigates the variation of flow behavior with step inclinations on different models at different velocities. Based on the literature review nine models were designed by using CATIA. The models used in this study are forward facing step, backward facing step and combination of forward and backward facing step with step inclination angles of 90 0 , 50 0 , 30 0 respectively. All these nine models were fabricated and tested in a low speed wind tunnel at different velocities to identify various flow zones and to understand the pressure distribution on the surface of the models and influence of velocity on flow zones are also determined.