新型混输泵球阀内气液两相流动的数值模拟

摘要

为了研究新型混输泵球阀内气液两相流动规律，建立了球阀内流场的三维模型，利用CFD软件，对阀内气液两相流动进行了数值模拟。在球阀开启高度为0．005 m时，对含气率分别为20％、40％、60％、80％4种工况的模拟结果进行了分析，得到了不同含气率下的速度场、压力场及气液两相相态分布，探讨了含气率对球阀内气液两相流动的影响规律。结果表明：阀隙处流速较大，压力梯度大，阀座倒角下端易气蚀；含气率对阀内流速大小影响较小，但对流态有影响。气体主要分布在阀球壁附近，远离球壁气体介质减少；当含气量逐渐增大时，气液两相的相界面处波动较大。研究结果揭示了阀内气液两相流动的规律，为内压缩混输泵气液单向阀相界面演化及失稳机制的研究提供参考。%In order to study the gas liquid two phase flow pattern ofthe new mixture pump ball valve , the three dimensional flow field of the ball valve model was established .Simulating the gas-liquid two-phase flow inside the valve by using CFD software was car-ried out.At open height of the ball valve was 0.005 meter, the gas rate of 20%, 40%, 60%, 80%four kinds of working condition , simulation result was respectively analyzed , velocity field, pressure field and phase distribution of gas liquid two phase under different gas rate were obtained , and the influence law of gas rate to gas liquid two phase flow was discussed within the ball valve .Results show that in the valve clearance and velocity are larger , and in the pressure gradient is large , the lower seat chamfer is easy of cavitation . Gas rate has little influence of flow velocity , but affects the flow pattern .Gas is mainly distributed near the valve wall , away from the valve wallgas is less .When the gas content increased gradually , gas liquid two phase at phase interface is fluctuated largely .Research results reveal the law of gas liquid two phase flow in the valve , to provide certain reference for study of compressed mixture pumps gas liquid phase interface evolution and the mechanism of instability of a one-way valve .