弹丸气动力特性计算方法

A COMPUTATIONAL METHOD APPLICABLE TO BODY ALONE AERODYNAMICS OF PROJECTILES

本文介绍了制导与非制导单独强身亚、跨、超声速有攻角时的升力、阻力特性及压力中心的计算方法。其中超声速波阻采用 Van Dyke 二级扰动理论计算,跨声速波阻用半经验方法处理。其余如摩阻、底阻、粘性分离和旋转带的阻力均用经验方法计算。无粘升力特性,在超声速时用一级横流理论计算,亚、跨声速时采用半经验方法处理,粘性升力特性则全部用经验方法计算。这套方法已软件化,用一个源程序表出。计算结果表明,该方法对尖头、截平头和半球形头部的实际弹形均有相当好的升力、阻力特性计算精度,并能给出合理的压力中心计算结果。

In this paper,a computational method is described tosolve body alone aerodynamics of guided and unguided projectiles atsubsonic,transonic and supersonic Mach numbers,Herein,the secondorder perturbation theory of Van Dyke is adopted to calculate thesupersonic wave drag.Otherwise. those methods available for calculat-ing transonic wave drag,skin friction drag,base drag,viscous separationand rotating band drag are empirical procedures.At supersonic Machnumbers the inviscid lifting properties are calculated using Tsien'sfirst order cross flow theory.But at subsonic and transonic Mach num-bers the lifting properties are calculated using semiempirical proce-dures.At all Mach numbers the viscous lifting properties are calcu-lated using empirical procedures.The calculated results have shown thatthis method yields accuracies of ninety percent or better for mostconfigurations.