非定常激波三维双楔面反射的数值研究

NUMERICAL INVESTIGATION ON UNSTEADY SHOCK WAVE REFLECTIONS OVER THREE DIMENSIONAL INTERSECTING WEDGES

采用基于MUSCL-Hancock插值的有限体积方法,在非结构自适应网格上求解三维Euler方程,研究了非定常激波在三维垂直双楔面上的反射现象.研究结果表明,由于三维效应的影响,通过二维非定常激波反射理论预测的三维马赫反射区域范围存在着一定的局限,在该区域范围内出现了一种非典型的三维突起结构,即第二类三维马赫干.另外,对于不同的激波马赫数和楔面倾角组合,非定常激波在三维双楔面上会形成具有四波结构的三维马赫反射或具有三波结构的三维规则反射.

An investigation into unsteady shock wave reflections over three-dimensional intersecting wedges is described. The finite volume method with the MUSCL-Hancock interpretation is used on self-adaptive unstructured meshes. Numerical results demonstrate that three-dimensional Mach reflection region predicted by the relations of two-dimensional oblique shock wave reflection has limitations because of the three-dimensional effect of shock reflections. An atypical three-dimensional structure appears in this region, namely the second type of three-dimensional Mach stem. Besides, for different combinations of shock wave Mach numbers and wedge angles, the three-dimensional four-shock Mach reflections or three-shock regular reflections appear in the corner of the two intersecting wedges.