重力对气液两相横射流的影响分析

Effect of gravity on mix of underwater two-phase gas-liquid jet in cross flow

该文采用直接数值模拟研究了沿横流方向重力对平板单孔气-液两相横射流的影响规律。基于VOF方法,数值模拟捕捉到了清晰的瞬态气-液界面。研究结果表明:相比于不存在重力的情况,沿横流方向重力的存在会使流场中的气体受到逆横流方向的浮力。浮力有利于气体黏滞于固壁表面附近,具体表现为有重力算例的横截面平均气体体积分数和近壁面平均气体体积分数较高,平均流速较低。在近壁面区域,有重力算例的流线明显向上游回卷,而无重力算例的流线则呈现梭形。

Direct numerical simulation of two-phase gas-liquid flow is used to study the effect of gravity on the transverse jet flow.Transient sharp gas-liquid interface is obtained by using VOF method.The results show that compared to cases without gravity effects,the buoyancy force act makes it easier for gas to stick near the wall,results in a higher average volume fraction of gas phase and a lower average streamwise velocity.In the region close to the wall,the streamlines of cases existing gravity obviously turn back to the upstream,while those of cases without gravity show shuttle shape.