激波与氦气泡相互作用的实验与数值研究

提出了一种在激波管中实现运动激波与球形气一气界面相互作用的研究方案。以肥皂膜作为气体交界面，高压火花为光源，采用阴影法，在马赫数M=1．2的情况下，在矩形激波管中开展了一系列的实验研究，获得了激波作用下球形氦气泡界面发展变化的相关实验结果。还通过求解二维轴对称的Euler方程，结合网格自适应策略，对实验过程进行了数值模拟。通过与实验结果的对比分析，证实了涡量的产生和分布对于界面的变形和发展有着重要意义。

Experimental and numerical study on the interaction of shock wave with helium bubble in shock tube

The evolution of a spherical gas-gas interface impacted by a planar shock wave is studied in a shock tube. A soap film is used to create the gas-gas interface by separating the helium bubble from the work gas-air. The interface instability is visualized by means of shadowgraph. The development of the interface instability can be found from a series of shadowgraph pictures. First, the helium bubble starts to deform from sphere to ellipsoid when the planar shock interacts with it. Then the surrounding air begins to enter to the helium bubble and forms the spike and mushroom structures, and finally a turbulent mixing stage is reached. The numerical method solves the two-dimensional axi-symmetric Euler equation in an adaptive unstructured mesh. Experimental results are compared with numerical simulation, and a good agreement is found. It is found that the generation and distribution of vorticity during the interaction plays an important role for the deformation and development of the interface.