基于相场法对非牛顿流体中气泡聚并行为特性的仿真分析

Simulation Analysis of Bubble Coalescence Behavior in Non-Newtonian Fluid Based on Phase Field Method

气液两相流因稳定性好被广泛应用于化工生产的各个领域,其中气泡的聚并行为对气泡的大小、形状及运动有显著影响,这些参数直接影响如生物反应器、鼓泡塔等化工设备的相间传质传热过程和工艺性能。使用相场法通过仿真软件对非牛顿流体中的气泡聚并行为进行讨论,分别以气泡在对称分布、偏左分布或偏右分布三种相对位置情况下从竖直气泡、水平气泡和随机气泡三个方面分析对比了气泡的位置和分布对其聚并行为的影响。结果表明,在非牛顿流体中,气泡的相对距离和流体的流动特性都是气泡聚并能否发生的关键因素,它们在气泡处于不同的分布情况下表现出不同的作用规律;另外气泡在不同分布的情况下,其运动规律也表现为不同的特点。

Gas-liquid two-phase flow is widely used in various fields of chemical production because of its stability.The bubble coalescence behavior has a significant impact on the size,shape and movement of bubbles.These parameters are important parameters for affecting the interphase mass and heat transfer processes and equipment performance.This paper presents a simulation study of the bubble coalescence behavior of non-Newtonian fluids using the phase field method through simulation software.The relative location of bubbles were divided into three types:vertical,parallel and random;and also the distribution of bubbles can be divided into three cases:symmetric,left-skewed or right-skewed.This paper focuses on the influence of the arrangements of the bubbles on their coalescence behavior in non-Newtonian fluids.The results show that in non-Newtonian fluids,the relative distance of the bubbles and the flow characteristics of the fluid are both key factors in whether bubble coalescence can occur,and they exhibit different patterns of action when the bubbles are in different arrangements.Also bubbles show different patterns of motion in different distributions.