基于全矢量显式算法的双相流填充数值模拟

A Fully Vectorial and Explicit Algorithm for Numerical Simulation of the Bi-phasic Filling Flow

基于模拟填充过程显式算法,提出用于模拟双相流的全矢量化运算显式算法。在双相流混合理论的基础上,对各类双相流填充及组份分离现象进行模拟。为高效求解耦合的Navier Stokes方程,新算法中的矩阵操作仅在单元一级进行,避免全局求解,使全局操作完全矢量化。新算法的另一显著优势,是采用等阶插值的普通单元,使不可压缩条件通过反馈修正的方法得到满足,通过系统化的光顺处理来避免由于应用等阶插值而导致的自锁。由于全局操作完全矢量化,计算代价与节点的自由度近似成正比,可实现高效的双相流填充及组份分离现象的模拟,满足工业应用中模拟复杂实际问题的需要。

Based on the previous explicit algorithms for the simulation of filling process, a new explicit and vectorial algorithm for bi-phasic flow is proposed and developed. For the simulation of filling processes and phase segregation effects of bi-phasic flow, the bi-phasic model should be used, which induces the solution of coupled Navier-Stokes equations. In the newly developed algorithm, the matrix operations are strictly limited at the element level, all the global solutions are eliminated in order to provide the efficient algorithm with purely vectorial operations. Moreover, only the elements of equal-order interpolations are necessary in the realisation of this new algorithm. The condition of incompressibility is retained by a specially designed corrective feedback operation, with a systematic smoothing procedure to avoid the possibility of mesh lock. As all the global solutions are performed in vector forms, the computational cost is merely about proportional to the degree of freedom level. So the simulation of injection processes and phase segregation can be carried out with high efficiency, which provides the good suitability for simulation of the industrial problems on a large scale.