环形水气自激振荡射流泵提高传能效率分析与计算

Analysis and Numerical Simulation of Entrainment Efficiency in Annular Water-air Self-oscillating Jet Pump

提出环形自激振荡水射流概念,使用Realizable k-ε湍流模型对环形射流泵和环形自激振荡射流泵内部流动进行了仿真计算,结果表明:环形自激振荡射流泵提高了10%左右的吸气量;对两种射流泵内部流场进行了稳态计算,分析了面积比与吸气量之间的关系;通过瞬态计算阐述了下喷嘴处水气相间不稳定边界层的周期性运动发展过程。根据稳态和瞬态的模拟计算结果,总结出环形自激振荡射流提高对气体的卷吸效果的原因。这为提高射流泵传能效率,研制新型环形自激振荡水气射流泵奠定了理论和应用基础。

This paper presents the improved design of an annular water-air jet pump. The internal air-water twophase flow characteristics of both conventional and improved annular water-air jet pumps were numerically investigated with the adopted Realizable k-ε turbulence model. In addition,the air-water interface development was visualized by steady and unsteady numerical simulations. The numerical results demonstrate a 10% increase of air entrainment compared with the conventional design,which is mostly attributable to the improved mass and energy transfer process due to the introduction of self-excited oscillation effect. This study contributes to a better understanding of the annular water-air jet pump＇s flow mechanism and demonstrates the feasibility of incorporating self-excited oscillation cavity into annular water-air jet pump design.