球面微喷气-粒混合的物理建模与三维数值模拟

Modeling and Three-Dimension Numerical Simulation of Particle-Gas Mixing in Ejection with Spherical Sample Surface

基于自编气体-颗粒两相流程序,对球面会聚冲击波作用于样品球形自由面而形成的喷射颗粒与气体相互作用问题进行了三维数值模拟。根据微喷过程特点及文献数据,通过建模的方法确定颗粒初始分布状态,而运动自由面对气体的作用采用虚拟流体流-固耦合方法处理,并只考虑气体与颗粒之间的定常阻力。数值模拟给出了气体流场和颗粒的演化情况,颗粒云团自然地分成高密度低速区和低密度高速区,该结果与微喷实验的认识基本一致。

A three-dimension numerical simulation subjected to gas-particle two phase flow method is implemented to simulate the particle-gas interaction in spherical ejection,in which particles are ejected from shocked sample interface.Particles initial distribution is modeled accroding to characteristics of ejection processes and reference data.And action of the moving sample interface on gas is simulated by using ghost fluid coupling Eulerian-Lagrangian method.Only steady drag force between particles and gas is considered at present.The evolutions of gas flow and particles movements are shown in this paper.It is concluded that the particles naturally redistribute to a high-density low-velocity region and a low-density high-velocity region,which qualitatively agrees with basic acquaintance obtained from ejection experiments.