Wake Flow Investigation on Notchback MIRA Model by PIV Experiments

Abstract

To deepen our understanding of the flow field and flow mechanism of a car-like model, in this paper, an experimental investigation of the flow field of MIRA notchback 1/8 scale model is carried out using Particle Image Velocimetry (PIV) method. The tests are conducted in an open circuit wind tunnel at a Reynolds number of 9.16×105. In order to obtain the detailed flow field structure of the notchback model, the PIV method was used to capture the flow field images from three orthogonal directions. By studying the vorticity and velocity vector figures of both the time-averaged and instantaneous states, a three-dimensional flow field schematic of the notchback model is summarized, and the formation mechanism and development process of the vortices are analyzed. This study not only provides an intuitive display of the three-dimensional flow field structure of the MIRA notchback model but, more importantly, it provides a reference for the development of automobile aerodynamic drag reduction by analyzing the flow mechanism, which is beneficial to energy conservation.