多相流动的直接数值模拟进展

多相流动的直接数值模拟的讨论就是把流场中颗粒周围计算网格缩小到颗粒尺寸以下 进行流动的计算,颗粒的受力不是通过模型计算,而是通过积分表面的黏性力与压力获得. 直接模拟方法的出现标志着人们对多相流动的认识从宏观扩展到微观层次.主要介绍了 几种先进的直接模拟的方法:基于体适应的非结构化移动网格方法;基于固定网格方法;其 它方法.

DIRECT NUMERICAL SIMULATIONS OF MULTIPHASE FLOWS

In this paper, we discuss the direct numerical simulation of multiphase flows which is a method of solving the initial value problem for the motion of particles in fluids exactly, without approximation. The particles move according to Newton's laws under the action of hydrodynamic forces computed from the numerical solution of the fluid equations. DNS signifies that the knowledge of multiphase flows is extended to the microscopic level. This paper introduces several kinds of DNS methods: one based on body fitted moving unstructured grids, one based on fixed structured grids over which bodies move by a method involving a system of Lagrange multipliers, one based on fixed structured grids in the flow field but unstructured grids on the interface, and others.