高超声速气动力及激波位置快速计算方法研究

采用快速计算方法进行高超声速气动力计算时,影响计算精度的关键问题主要在于模型面网格的划分和计算方法的选取。采用一种灵活实用的结构化面网格划分策略,使得模型的各个部件能分别选择合适的计算方法;发展一种基于近似流线的二阶激波膨胀波方法,该方法可以用于多种具有三维流场特性的部件,不仅降低对使用者的经验依赖,还能提高计算精度;配合激波位置计算方法,可以较为准确地计算模型的激波位置,保证边界层外缘参数的计算精度;粘性力计算使用基于起始面元修正的Spalding-Chi方法和参考温度方法。通过对四个典型算例的计算与分析,表明本文发展的高超声速气动力计算方法具有较高的计算精度,能够作为高超声速飞行器初步设计阶段的气动力快速分析工具。

Research on engineering method and shock position prediction for hypersonic aerodynamics

The key of the computational accuracy, when calculating the aerodynamics of hypersonic by engineering methods, is the strategy for grid generation and the option of engineering methods. In this paper, a utility and easy-to-use method of grid generation is used, which allows each component of the model to use different computational method respectively; two order shock expansion method based on the approximate streamline fitting for many kinds of components with higher accuracy and less dependence on the experience of users is first introduced; when adding shock angle calculation in the two order shock expansion method, shock position of the model can be predicted; Spalding-Chi method based on initial surface element correct can supply more accurate viscous force coefficient compared with temperature reference method. The four cases indicate that, present methods have more accurate solutions when calculating aerodynamics of hypersonic, which can be used for preliminary design of hypersonic aircraft.