不同密度回转体高速倾斜入水空化数值模拟

Numerical Simulation on the Cavitation Flow of High Speed Oblique Water Entry of Revolution Body with Different Density

为探究回转体材料密度对其高速入水空化流动特性的影响,开展了回转体入水空化仿真研究。基于有限体积法和流体体积函数多相流模型、Schnerr-Sauer空化模型、SST k-ω湍流模型,结合动网格技术,对初速度为300 m/s的不同密度回转体倾斜入水过程进行数值计算,分析不同密度回转体入水过程中的空泡形态发展规律、运动特性及流体动力特性的变化规律。结果表明:所提数值计算方法能够有效模拟回转体入水过程中的空泡形态变化过程,密度越大的回转体入水后产生的空泡轮廓直径越小,空泡越长,空泡开口处直径越小;不同密度回转体入水瞬间回转体表面压力峰值相当,但密度越大的回转体表面压力衰减越慢;密度较大的回转体入水瞬间加速度峰值越小,入水后速度衰减越慢,相同时间内入水深度越大。

To explore the effect of material density on the high-speed water entry cavitation flow field of revolution body,the oblique water entry of revolution body with different density at initial velocity of 300 m/s is numerically simulated based on the finite volume method,volume of fluid(VOF)multiphase model,Schnerr-Sauer cavity model,SST k-ωturbulence model and dynamic mesh method.The evolution law of cavity shape,and the motion characteristics and hydrodynamic characteristics of revolution body during its water entry are analyzed.The research results show that the numerical calculation method can effectively simulate the change of cavity shape during the water entry of revolution body.The larger the density is,the smaller the diameter of cavity formed after entering water is,the longer the cavity is,and the smaller the diameter of cavity opening is;the peak values of pressure on the surface of revolution body with different density are the same at the moment of entering water,but the surface pressure on the revolution body with larger density declines slowly;the larger the density is,the smaller the acceleration peak value of revolution body at the moment of entering water is,the slower the velocity decay after entering water is,and the deeper the water entry depth is.