| With the development of empress highway and increase of the speed, the request on driving stability, dynamic characteristics, security and comfort is increasing. The automotive aerodynamic performance has become one of the important properties of road vehicle. It covers three great themes, that is to say Energy-economy, Security, Environmental protection. Currently, the wind tunnel experiment is an important method of automotive aerodynamic test. A large number of academic results are obtained from the experiments. On account of the basic research for automotive aerodynamics starting later, especially experiment research for aerodynamic characteristics in the wind tunnel, it has become one of main technological bottlenecks of constraining automotive research- independence. Therefore, the research on wind tunnel experiment of automotive aerodynamics has very practical significance.This paper has carried out detailed research into wind tunnel experiment for automotive aerodynamics in HD-2 wind tunnel platform of Hunan University. In this paper, the basic principle and methods of automotive wind tunnel experiment, experimental regulations, and the correction methods of test results have been stated, and the influence factors of wind tunnel test data are also analyzed. The relationship between the aerodynamic coefficient and Reynolds numbers is investigated, and the effect of aerodynamic performance is analyzed with suction or without suction. Crosswind acting on vehicle performance has been simulated, and the aerodynamic characteristics are evaluated for the vehicle. Then, a car model has been made experiment on. The aerodynamic drag has been reduced using ten local optimization schemes. And the effect of each scheme has been discussed in detail. Finally, the performance of vehicle has compared with the rearview mirror and former air spoiler.Flow visualization is the important method in the aerodynamic experiment. In this paper, Advanced measure technology——Particle Image Velocimetry (PIV) technology is applied to measure the wake three-dimensional flow field. The wake flow field and the turbulent flow characteristics of vortices have been discussed. And this thesis has researched on scattering particles, selecting time parameter about laser pulse and PIV calibration. The program of flow field measurement is established in the wind tunnel experiment, and lays the foundation for measuring the flow field of vehicle. |
PDF Full Text Request