绕流流场无穷远处流函数边值条件的数值研究

Numerical Study of Far-field Stream Function Conditions for the Flow around a Body

利用流函数—涡量方程求解二维不可压缩低雷诺数绕圆柱流动,在与其它学者计算结果一致的情况下,本文数值研究了无穷远处流函数边值对圆柱定常绕流、圆柱起动流动以及非定常周期性卡门涡街形成的影响。本文计算了各种条件下绕圆柱的阻力系数、流函数涡量分布以及扰动流函数等。计算结果显示,对于定常绕流及圆柱起动流动,几种无穷远流函数边值条件求得的结果基本一致。对于非定常周期性圆柱绕流,不同的无穷远流函数边值条件对计算结果有较大影响。

In the paper the stream-vorticity equations are solved for two-dimensional incompressible low Reynolds number flow around a circular cylinder. In the case that some calculations are compared well with the results of other researchers, far-field stream function conditions are studied numerically for steady flow,for starting flow and for periodic flow of the circular cylinder. The drag coefficient, the stream function and vorticity, the perturbed stream function are calculated under various conditions. For steady and starting flow with the different far-field stream function conditions, the computing results show the same accuracy. For the periodic flow of the circular cylinder different far-field stream function conditions have great effects on the calculation results.