颗粒密度与半径影响下的多相RMI混合区域宽度极限理论模型及其规律探究

Particle parameters have a significant impact on the evolution of the mixing zone width of the multiphase Richtmyer-Meshkov instability (RMI), but the influence law remains to be explored. Based on the interface motion equation and integrating the influence of particle volume fraction, radius and gas viscosity parameters, this article proposes a dimensionless number Sd to characterize the effect of drag on the fluid velocity relaxation process. A growth model for the mixing zone width under extreme particle parameters is established based on the small-perturbation theory. The analysis showed that the combination of particle density and particle size determines the growth pattern of the mixing zone width. It shows exponential growth when the particle density is large, and linear growth when the radius is large or both are large. Further analysis revealed the influence of changes in particle parameters on the mixing zone width, and found that increasing the particle radius will promote the growth of the mixing zone width. The numerical simulation results verify the validity of the theoretical model and Sd number. The results indicate that the classical Stokes number (St) fails in predicting the growth of the mixing zone width, and the combination of St number and Sd number is the dominant dimensionless number for the evolution of multiphase RMI.