关键词: 机翼, 气动设计准则, 压力分布, 优化, 计算机辅助工程

Abstract:

The aerodynamic characteristics of an wing play a critical role in the economics, safety, comfort and environmental protection of an aeroplane. However, the aerodynamic design processes are highly complicated, which should follow principles of wing aerodynamic design to obtain practical engineering value. Computer-aided engineering (CAE) based wing optimization requires less manpower, yet it may not guarantee that the design principles are observed and its results still call for a great deal of subsequent processing. Thus, in recent engineering applications, the aerodynamic design process adopted still relies highly on the experiences of the designers, which means a large amount of manpower. The purpose of this research is to improve the practical engineering value of the wing optimization results, so as to reduce the amount of subsequent processing and improve the efficiency of the wing design process. It first analyzes the wing surface pressure distribution. And then, according to the wing aerodynamic design principles, a new objective function is constructed based on the traditional objective functions determined from lift and drag characteristics. Finally, the new objective function is substituted into the optimization process. The results of this optimization are in keeping with the principles of aerodynamic design of the wing, and possess practical engineering value. Compared with traditional optimization processes, whose objectives are determined by lift and drag characteristics only, the method introduces hardly any additional time cost. The research results show that the lift and drag characteristics cannot comprehensively describe the aerodynamic characteristicss of the wing. Therefore, the objective functions based on them cannot guarantee the design principles to be followed, which makes them of little value in practical engineering application. On the contrary, the objective function which is constructed according to the wing aerodynamic design principles can guarantee the design principles to be followed in the optimization process, and efficiently improve the practical engineering value of the design results.

Key words: wing, aerodynamic design principle, pressure distribution, optimization, computer-aided engineering