叶顶间隙与轴向间距耦合对喷泵流场影响的数值分析  

Numerical Analysis of Infl uence of Coupling of Blade Tip Clearance and Axial Gap on Flow Field of Water-jet Pump

作　　者：冯德胜 苏石川[1] 王声森 魏承印 FENG De-sheng;SU Shi-chuan;WANG Sheng-sen;WEI Cheng-yin(School of Energy and Power Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)

机构地区：[1]江苏科技大学能源与动力工程学院,镇江212003

出　　处：《船舶》2018年第3期11-17,共7页Ship & Boat

摘　　要：以某艇用喷泵为研究对象,取1mm和1.5mm两种叶顶间隙以及5.6mm、11.2mm、16.8mm三种叶轮-导叶间距耦合,采用剪切应力湍流模型基于CFX软件进行多种流量工况下的流动模拟,分析不同耦合情况对喷泵流场的影响。结果表明:不同的耦合情况均对流场产生明显影响。耦合情况为1-16.8时,喷泵效率最高达到85.08%,相对提升4.44%;耦合情况为1.5-5.6时,吸力面负压区域减少,有利于叶片表面静压分布,但叶轮区域内泄漏流与主流的混渗效应加强;叶顶间隙变大会削弱轴向间距变化对叶顶间隙压差造成的影响。文章从耦合的角度分析,较仅考虑单一因素更为全面。分析结果对于喷泵设计及使用过程中性能变化的分析有一定参考价值。The simulation of a water-jet pump on a yacht has been conducted under the various flow conditions to analyze the influence of the coupling of the blade tip clearance and the impeller-guide gap on the flow field of the water-jet pump by using the shear stress turbulence model based on CFX. Two blade tip clearance of 1 mm and 1.5 mm are coupled with the three impeller-guide gap of 5.6 mm, 11.2 mm and 16.8 mm. The results show that the different coupling conditions have obvious influence on the flow field. The maximum pump efficiency reaches to 85.08% at the coupling condition of 1-16.8 with the relative increase of 4.44%. A reduced negative pressure area on the suction surface is observed under the coupling condition of 1.5-5.6, resulting in the favorable static pressure distribution of the blade surface, however, with the enhanced mixing effect between the leakage flow and the main flow in the impeller region. The increase of the blade tip clearance weakens the effect of the change of the axial gap on the pressure difference of the blade tip clearance. The analysis from the coupling viewpoint is more comprehensive than that with the consideration of single factor. The results can provide reference for the design of the water-jet pump and the analysis of the performance change during the operations.

关 键 词：喷泵 叶顶间隙 轴向间距 泵效率 叶顶间隙压差 静压分布 流线 

分 类 号：U664.34[交通运输工程—船舶及航道工程]