带尖针杆的钝体粘性绕流的数值模拟

NUMERICAL SIMULATION OF HYPERSONIC FLOW OVER AXISYMMETRIC SPIKED BODY

用无波动、无自由参数耗散的差分（ＮＮＤ）格式数值求解了Ｎ－Ｓ方程，模拟了尖锥柱与球头组合体的高超音速粘性流动；清晰地给出了激波、膨胀波、剪切层和旋涡等流动图象。计算给出的定常流场与实验图象甚为一致。通过数值模拟研究了激波、旋涡的形成和发展过程以及相互作用情况。发现分离区中的旋涡存在分叉、合并及二次分离等演变历程。钝体主激波和分离激波从开始形成到相互撞击；发展到在与分离区相互干扰下向前、向后运动和变形；最后趋于定常状态。

In this paper the hypersoinc viscous flow over a spiked hemisphere has been simulated numerically. The complex flow features including shock waves,expansion waves,shear layer and vortices have been captured successfully,Meanwhile, the phenomena,such as the bifurcation and mergence of vorticesf secondary separation and so on,have been found.It is shown that the calcu-lated pressure distribution along the body surface and flow pattern are in good agreement with the experiments.