矩形风洞收缩段流场的计算和分析

本文结合西工大低速风洞设计进行了矩形三元收缩段流场的计算和分析,计算采用差分方法和贴体坐标,以AF1格式进行离散化并利用ADI方法求解。对三种常用的收缩曲线(即Witozinsky曲线,五次方曲线和双三次方曲线)的三元流场进行了具体计算和比较。计算结果正确反映了三元收缩段流动的特点,给出了流动三元性对壁面逆压梯度和出口均匀性影响的数值结果,表明本文方法是三元收缩段设计的有效分析和设计手段。

FLOW ANALYSIS OF RECTANGULAR WIND TUNNEL CONTRACTION

In connection with the design of a low speed wind tunnel in Northwestern Polytechnical University, numerical investigation of the flow in rectangular contraction has been conducted. Finite difference method is employed, using body-fitted coordinates and AF1 scheme, and solved by ADI technique. The flows in three commonly used contour curves are analyzed, i. e. Witozinsky curve, fifth power curve and matched cubic curves. Three-dimensional features of the contraction flow are demonstrated in the calculation. The adverse pressure gradient at the corner and the velocity non-uniformity at the exit cross section are calculated and examined.