基于熵产分析的喷水推进泵空化特性研究  

Cavitation characteristics of water-jet pump based on entropy production analysis

作　　者：郭嫱 费宗岳 黄先北 仇宝云 石丽建 GUO Qiang;FEI Zong-yue;HUANG Xian-bei;QIU Bao-yun;SHI Li-jian(College of Electrical,Energy and Power Engineering,Yangzhou University,Yangzhou 225127,China;College of Hydraulic Science and Engineering,Yangzhou University,Yangzhou 225127,China)

机构地区：[1]扬州大学电气与能源动力工程学院,江苏扬州225127 [2]扬州大学水利科学与工程学院,江苏扬州225127

出　　处：《船舶力学》2024年第10期1507-1515,共9页Journal of Ship Mechanics

基　　金：国家自然科学基金资助项目(52276041,52379093,52179091,52209116);江苏省水利科技项目(2022016);扬州大学“青蓝工程”资助项目。

摘　　要：喷水推进泵广泛应用于船舶动力等领域,其内部的空化流动特性对于推进性能具有重要影响。为了对空化流场中的能量损失进行定量评价,基于熵产理论对某轴流式喷水推进泵进行空化特性研究。由于叶顶间隙涡空化在轴流式推进泵中十分典型,数值方法中考虑局部涡流特性,采用旋转修正的SST-CC湍流模型和基于涡识别修正的空化模型,并根据模型泵的参考实验验证数值计算方法。研究结果表明:在不同空化系数条件下,随着空化程度的加剧,熵产值的增大反映了推进泵能量损失的增大,对应效率曲线的下降,泵内总熵产的变化规律与其功率特性基本一致。分析推进泵各段几何区域的能量损失可见,叶轮段的熵产占比最高,尤以湍流耗散和壁面耗散更为显著,这与叶轮叶顶间隙的涡流和空化流场密切相关。研究叶轮叶顶的流动特征可见,在不同空化条件下,叶顶间隙泄漏涡区域引发了旋涡空化,但显著的能量耗散出现在泄漏涡的外缘及附近壁面区域,而叶片表面的附着空化涡则是湍流耗散的主要来源。Water-jet pumps are widely used in power fields such as ships,and the internal cavitation flow characteristics have an important impact on propulsion performance.In order to quantitatively evaluate the energy loss in cavitation flow field,the cavitation characteristics of an axial water-jet pump were studied based on entropy production theory.As the tip clearance vortex cavitation is typical in axial-flow propulsion pumps,the local vortical flow features were considered in the present numerical method.The SST-CC turbulence model with rotation correction and a modified cavitation model based on vortex identification were adopted.The numerical calculation method was verified according to the referenced experiment of a model pump.The results show that,under different cavitation conditions,with the deterioration of cavitation,the increase of entropy production value reflects the increase of energy loss of water-jet pump,which is corresponding to the decrease of efficiency curve,and the change law of total entropy production in pump is basically consistent with its power characteristics.Analysis of the energy loss in each geometrical region of the water-jet pump shows that the entropy production in the impeller section is the highest,especially the turbulent dissipation and wall dissipation,which are closely related to the vortex and cavitation flow field in the tip clearance of the impeller.On the different cavitation conditions,study on the flow characteristics at the tip of the impeller shows that the tip leakage vortex region causes cavitation,but significant energy dissipation occurs at the outer edge of leakage vortex and on the nearby wall area,while the cavitating vortex attached on the blade surface is the main source of turbulent dissipation.

关 键 词：喷水推进泵 熵产理论 空化 间隙 数值模拟 

分 类 号：U664.34[交通运输工程—船舶及航道工程]