前缘剖面形状对80°／60°后掠双三角翼上涡流运动影响的数值模拟研究

采用上风高分辨率格式———通量差分分裂格式离散求解三维可压非定常薄层N S方程 ,数值模拟前缘剖面形状对 80°/60°后掠双三角翼上涡流运动的影响。计算模型包括尖前缘、菱形前缘、圆形前缘等三种不同前缘形状的机翼。计算结果表明 :三种不同剖面形状的前缘可以诱导产生不同的前缘分离 ,形成的各前缘剪切层的特点也不同。尖前缘机翼的边条翼涡和外翼涡合并点最靠前 ,其次为菱形前缘和圆形前缘的机翼。在大迎角情况下 ,三种机翼上的内翼涡发生破裂。圆形前缘机翼上的内翼涡破裂点比其它两种情况下破裂点的位置较靠前。涡的合并对二次涡的结构和特点也有显著的影响。

Numerical investigation of the effects of different leading-edge profiles on vortical flows over a double-delta wing

In this paper, the effects of different leading edge profiles on vortical flows over a double delta wing with sweep angles of 80/60 degrees were widely investigated numerically. To simulate the complex flows over double delta wings with different leading edge profiles, a high resolution upwind flux difference splitting scheme was used to solve the 3 D compressible unsteady NS equations. The three different leading edge profiles were round, single sharp and double sharp. The results showed that different leading edge profiles could induce different forms of separation and that the induced shear layers are also different. The combination of the inner and outer vortices resulting from single sharp profiles happens earlier than those resulting from double sharp profiles and round profiles respectively. At high angles of attack, for instance 35 degrees, the vortex breakdowns can be visualized over all the three kinds of wings. The effects of the vortex breakdown on the structures of the secondary vortices were also discussed in this paper.