基于LDV测量速度场计算三维机翼表面压力分布

3-D Wing Pressure Distribution Calculation Based on Measured Flow Velocity by Using LDV Unit

本文基于线路积分原理，用LDV测量三维机翼周围的速度场，然后把它们作为已知量代入到雷诺方程、欧拉方程和贝努利方程中去求解压力。在换算机翼表面压力分布时，分别采用了把物体表面上的点经过处理后作为一个正常节点来处理的做法（方法1）和以最邻近物面的节点处压力代替物面压力的做法（方法2）。结果显示了方法1要比方法2计算出的结果精确。本文的研究表明，总压是由贝努利项、涡项和雷诺应力项共同作用的结果，三维物体的各项压力分布特性不同于二维问题。本文的换算结果再次表明线路积分方法对于获得三维物体表面的压力分布也是可行的，精度是高的。这一技术的解决将为求得螺旋桨等复杂三维物体表面的压力分布打下良好的基础。

The principle of pressure distribution calculation based on the measured velocity field along the path of integration is presented by RANS equation for a 3-D wing. A comparison of pressure between calculated values based on measured velocity data and directly measured values was made to check calculating methods.Two methods are used to transform the calculated pressure results into the surface pressure distribution on the 3D wing. One is to regard the point at the surface as a common node point in the field to deal with (Method 1).The other method is to use the pressure value of node point which is the closest to surface in the flow field, to be instead of the one surface (Method 2). The results show that calculated values of Method 2 are quite agreeable to those directly measured. More errors will occur during transforming velocity into pressure according to traditional Bernoulli equation at flow field of a 3-D wing body. The results developed in this paper are quite satisfactory.