中等Reynolds数下并列方柱统流的数值模拟──MAC－AF1方法及其应用

本文通过采用ＭＡＣ－ＡＦ１方法求解原始变量二维不可压非定常Ｎａｖｉｅｒ－Ｓｔｏｋｅｓ方程，对中等Ｒａｙｎｏｌｄｓ数绕流下的并列方柱绕流进行了数值模拟。通过对Ｒｅ＝３００、５００、１０００、２０００及间隙度为ｓ／ｈ＝２．３时并列方柱的数值计算表明：Ｒｅ数对横向力的变化频率毫无影响，恰好是单方柱绕流横向力变化频率的两倍。阻力的频率与横向力的频率相同，阻力的时间平均值基本上与Ｒｅ数无关，但随着Ｒｅ数的增大，阻力和横向力随时间变化的波动幅度稍微有所增加。本文计算的方柱阻力时间平均值和横向力的频率与实验值符合得很好。

Numerical Simulation of Flow around Square Cylinders Arranged Side-by-Side under Moderate Re Number

In this paper,in order to take the simulation of flow around square cylinders arranged side by side under moderate Reynolds number, the two dimensional incompressible time dependent Navier-Stokes equations with primitive variables have been solved by MAC-AF1 numerical scheme. For the cases of Reynolds number Re = 300, 500, 1000, 2000 and gap ratio s/h =2. 3, the numerical results indicate: The Reynolds number has no influence on the frequency is just the double frequency in the case of flow around single square cylinder:the frequency of drag force is the same as drag force,and the frequncy of lift force, to a great extent, the time averaged value of drag force is irrespective of Reynolds number, but the amplitude of time dependent drag and lift force is increased a bit as the Reynolds number increased.The numerical results show that the frequency of lift force and time averaged value of drag force are in good agreement with existed experimental datas.