Experimental research on Richtmyer-Meshkov instability at the multi-layered fluids interfaces with different density gradients

This paper is based on our previous study of the Richtmyer-Meshkov(RM) instability research of a gas-liquid interface.Using the fluids with different densities,one can build two kinds of three-phase interfaces of gas-liquid-liquid,i.e.,gas-silicone oil-water and gas-alcohol-silicone oil interfaces,which have totally different direction of viscosity gradient.In the experiment,we use nitrogen gas as the high pressure driving gas and measure the development of spike height and bubble depth from these two interfaces at different shock wave Mach numbers.After analyzing all the experimental data we find some regular flow patterns.Then we compare the regular pattern with the results that we have already known.Meanwhile,the difference between the two kinds of three-phase interfaces in R-M instability development is also studied in this paper.The result shows that when the liquid viscosity gradient direction is agreed with the shock wave motion direction,the instability of the interface and the turbulent mixing become more significant.