集中涡法在计算旋成体大迎角气动特性中的应用

本文用集中涡法计算了尖头旋成体在大迎角时的气动特性。基于实验数据,选取了一组比较合适的自由积分参数,建立了初始分离角和雷诺数之间的经验关系式,从而在计算中较好地考虑了雷诺数的影响。马赫数的影响是通过Gthert法则进行修正予以考虑的。旋涡运动的微分方程组是用变步长的四阶龙格-库塔法来求解的。根据不同的积分位置分别选择三种不同的积分初始步长,以提高计算速度。本文对F_3A16和F3.5A7两种模型作了计算,计算结果和实验结果吻合得较好。

THE APPLICATION OF CONCENTRIC VORTEX SIMULATION TO CALCULATING THE AERODYNAMIC CHARACTERISTICS OF BODIES OF REVOLUTION AT HIGH ANGLES OF ATTACK

The aerodynamic characteristics of sharp nosed bodies of revolution is calculated by using concentric vortex simulation in this paper. Based on the experimental results, an appropriate set of free integration parameters is selected and an empirical relation between initial separation angle and Reynolds number is established, thus, the effect of Reynolds number is considered reasonablely in the calculation. The effect of Mach number is corrected by using Gothert's rule. The differential equations of vortex motion are solved by using forth order Runge-Kutta method with varying step size. Three different initial step sizes are used in different integration positions in order to increase the speed of calculation. Two models (F3A16 and F3. 5A7) were calculated in this paper. The comparison of calculation results with experimental results has shown that the coincidence is satisfactory.