均质腔内壁微结构对均质性能影响的仿真分析

Simulation analysis of the effecton homogeneous performance from micro structure of homogeneous cavity inner wall

基于壁面粗糙度引起流动状态变化的现象,为进一步研究高压均质机内均质腔内壁表面的微结构对均质性能的影响,在光滑均质腔内壁构建沟槽状微结构,采用计算机流体动力学(CFD)技术对均质腔内两相流动过程进行仿真。以APV实验型高压均质机内的均质腔为研究对象,将油-水乳液作为均质物料,分别对光滑均质腔,矩形截面沟槽均质腔,以及三角形截面沟槽均质腔内的均质过程进行仿真计算,并做对比分析。结果表明:有沟槽的均质腔均质粒径更小,而矩形截面沟槽较三角形截面沟槽均质得到的粒径更小,同时粒度分布更均匀,有利于提高均质性能;计算机仿真结果与湍流近壁区理论分析结果趋势一致。

Based on the phenomenon that the change of flow state caused by the wall roughness,in order to research the effect of micro structure on the surface of the inner wall of the high pressure homogenization cavity in the high pressure homogenizer to homogenization performance,the groove micro structure is structured on the inner of smooth homogenization cavity,and a computer fluid dynamics（CFD）technique is used to model the two-phase flow in a high pressure homogenizer.This paper will study the high pressure homogenization cavity in the APV-high pressure homogenizer,the oil-water emulsion as the homogeneous materials,the smooth homogeneous cavity and the rectangular section groove homogeneous cavity and the triangular section groove homogeneous cavity are simulated and calculated respectively,and the results are compared.The results show that the homogeneous cavity with groove which has a smaller particle size than the smooth homogeneous cavity after homogenization,the rectangular section groove homogeneous cavity has a smaller particle size than the triangular section groove homogeneous cavity after homogenization,at the same time the particle size distribution is more uniform,improved the homogeneous performance.The results of computer simulation to the results trend obtained by the theoretical analysis of the turbulent near-wall region shows very good agreement.