Investigation And Improvement On Aerodynamic Characteristic Of Zhongqi Car Based Internal And External Flow Field

Automotive aerodynamic characteristic is not only the premise and theoretical basis for the automobile body styling, it is an important indicator to evaluate automobile performance, and has three great motives of Energy-economy, Security, Environmental protection. The aerodynamic research can help us improve the dynamic characteristics, fuel economy and driving stability. It is the important factor that for car to succeed in the drastic automobile industry. The airflow characteristic of underbody and Underhood is one of the key factors which influence the aerodynamic characteristic of car.Detailedly researching on it is one of the important and hardy problems for field of Computational Fluid Dynamics.The time of starting in Basic research for automotive aerodynamics is very late, and research on key technique of aerodynamics is lack of in-depth study. Now, these become one of main technological bottlenecks of constraining national automobile. Therefore, strengthening base research of automobile aerodynamics key technology and finally coming to being a completely integrated method for automobile body aerodynamic designing will greatly promote research-independent and innovation ability of our country’s automotive industry.This paper has carried out detailed research into airflow of internal and external flow field on Zhongqi program. The theory and researching way of automotive aerodynamic is described. Analysis of the results can give a beneficial basis for car designing.Before the application of commercial software and the way of numerical analysis, a very important work is to evaluate credibility of it. This thesis uses the method of comparison between experiment result and computation result of a standard model car. Through the numerical simulation, the aerodynamic characteristic of external flow and interference force of Zhongqi car are obtained.A new mathematical approach is developed to analysis the complex airside flow of internal and external. Airflow characteristic of underbody is detailed research. The influence to internal force is clarified.Based on the cars’aerodynamic characteristic of external flow, application of optimization of detail shape which contacts cars’shape and aerodynamic attachment devices is proposed for reducing aerodynamic drag.