基于欧拉-拉格朗日方法的空化模型改进与应用  

Application of a Modified Cavitation Model Based on Euler-Lagrangian Method

作　　者：王静[1] 闫康昊 赵金海 黄丹[1] WANG Jing;YAN Kanghao;ZHAO Jinhai;HUANG Dan(College of Mechanics and Engineering Science,Hohai University,Nanjing Jiangsu 211100,China)

机构地区：[1]河海大学力学与工程科学学院,江苏南京211100

出　　处：《机床与液压》2024年第21期112-117,共6页Machine Tool & Hydraulics

摘　　要：针对现有空化模型经验参数较多影响预测精度的问题,提出改进的空化模型。采用欧拉-拉格朗日方法模拟不凝性气体与空化气泡的融合过程,得到气泡数密度与液体体积分数的关系。结合气泡在液体中的力平衡状态和气体状态方程,得到气泡半径的表达式。基于简化的Rayleigh-Plesset方程建立空化模型,将不凝性气体摩尔浓度确定为唯一需要指定的参数。最后,将改进模型和ZGB模型应用于节流孔板和文丘里管,并与文献中的实验结果进行对比。结果表明:改进的空化模型能准确地预测空化流,并且对于非定常空化流,可以捕捉到空化初生、发展、分离、脱落和溃灭的周期性过程。Aiming at the problem that existing cavitation model has multiple empirical parameters that affect the accuracy of the prediction,a modified cavitation model was proposed.The merging process of non-condensable gas and vapor bubbles was simulated by the Euler-Lagrangian method,and the relationship between the bubble number density and the liquid volume fraction was obtained.According to the bubble force balance in the liquid and the ideal gas state equation,the expression of the bubble radius was acquired.The modified cavitation model was established based on the simplified Rayleigh-Plesset equation,and the molarity of non-condensable gas was the only parameter that must be specified.Finally,the modified cavitation model and ZGB model were applied to a orifice plate and a venturi tube,and the results were compared with available experimental data in the literature.The results show that the modified cavitation model predicts cavitating flows more accurately.In addition,the periodic stages of cavitation inception,development,separation,shedding and collapse can be captured for unsteady cavitating flows.

关 键 词：空化模型 Rayleigh-Plesset方程 欧拉-拉格朗日方法 不凝性气体 

分 类 号：TH137.8[机械工程—机械制造及自动化] O359[理学—流体力学]