Experiment and Nemerical Prediction for Onset of od Three Diemnsional Separation

在补助金的期限内，对以下项目进行核查或设计。1.本文提出了一种简单的可视化技术，它能在拖曳水池中沿模型沿着的极限流线提供示踪剂的记录。以轴对称抛物面和沿着垂直于平板的圆柱为例，给出了可视化结果.对于旋转抛物面，计算结果与Bippes的结果一致，闭合分离线起始的临界角高达62 °左右.采用氢气泡方法显示了流场中的涡，对于抛物面情况，可以消除侧涡的交替脱落.在风洞中测量了抛物面上方的静压，并证实了在主分离线后面存在与二维分离一样的azunytgak压力分布平台。在柱-板交界处的流动中，可以观察到节点、鞍点和焦点，焦点的位置随柱后双涡长度的变化而周期性地移动.本文发展了三维Navier-Stokes方程有限差分计算结果和边界层解的计算机图形显示技术。

During the term of the Grant-in -aid the following items are verified or devised. 1. A simple Visualization technique is proposed which provides a record of tracer for the limitting streamlines along a model in a towing tank.Electrolysis method is applied with painting the phenolphtalein solution on a body surface. The visualization results over axisymmetric paraboloid and along a circular cylinder normal to flat plate are shown as examples.2. The results for paraboloid of revolution show a good agreement with those by Bippes as for the critical angles for the onset of closed separation line as high as 62 deg or so.3. Hydrogen bubble methods is also applied to visualize vorticis in the flowfields.For the case fo paraboloid the alternative shedding of lateral vortices canbe observed.4. Static pressure over the paraboloid was measured in a wind tunnel and a plateau of azunytgak oressyre distribution as in 2-D seqaration was confirmed behind primary separatin lines.5. As for the flow near the cylinder-plate juncture the nodes,saddles,and foci can be observed.The locations of foci move cyclically with the length of twin vortices behind the cylinder.6. Illustrating techniques of three dimensional flows in computer graphics are developed for the results of finite difference computation for tridimensional Navier Stokes equations as well as boundary layer solutions.