特种涡轮驱动混流泵瞬态空化特性  

Transient cavitation characteristics of a special mixed-flow turbopump

作　　者：张德胜[1] 施卫东[1] 郎涛[1] 张华[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,江苏镇江212013

出　　处：《华中科技大学学报（自然科学版）》2014年第2期40-45,共6页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51109093);江苏省自然科学基金资助项目(BK2011503);中国博士后科学基金面上资助项目(2011T500117);中国博士后科学基金特别资助项目(2012T50468);江苏高校优势学科建设工程资助项目

摘　　要：为了研究水泵液压系统瞬态特性，建立了水泵液压系统运动物速度和泵转速的瞬态数学模型，分析了涡轮泵启动瞬态过程中0．73，0．90和1．00s三个典型时刻运动物速度与加速度、泵流量及其空化特性．数值模拟结果表明：不同NPSH工况叶片表面空泡分布规律一致，在叶片弦跨度0．7～1．0区域，空泡体积分数向轮缘方向迅速增大，在轮缘区达到最大值；在运动物出舱工况下，当装置空化余量为14．23 m时，轮缘圆周面上平均空穴面积达到33％左右，空泡堵塞了叶片流道，导致泵扬程下降了约61％，满足不了水泵液压系统运动物的加速度要求．模型泵试验结果表明：水泵液压系统涡轮泵启动后，泵转速近似线性加速，泵的必需空化余量值随之迅速增大，在运动物出舱时涡轮泵转速、流量和必需空化余量均达到最大值，为了避免涡轮泵叶轮空化诱导运动物出舱失败，应规定水泵液压系统最小潜水深度．In order to investigate the transient characteristic of pump hydraulic pressure system , mathematical models of the equipment transient velocity and pump transient speed were established based on the experimental data .T he cavitation characteristics at 0 .73 ,0 .90 and 1 .00 s moments dur-ing the pump starting transient process were analyzed .Numerical results show that distribution of cavitation bubble volume fraction in the suction side of blades at the different net positive suction head （NPSH） conditions is similar .The volume fraction of cavitation bubble increases sharply from the span of 0 .7 to 1 .0 ,and reaches the maximum value at the rim .At the time when the equipment gets out of cabin ,the average cavity fraction in the rim circumferential surface is about 33% at the condi-tion of the available not positive suction head （NPSH） Na=14 .23 m .In this case ,the cavitation bub-bles block the flow channels ,which results in the sharp drop of the pump head ,and will affect the e-quipment acceleration .The experimental results show that the pump rotating speed is accelerating ap-proximately linearly after the starting of the pump hydraulic pressure system ,and the NPSH value of the pump increases rapidly with increasing speed of the turbopump .The rotation speed ,flow rate and the net positive suction head required （NPSHR） all reach the maximum values at the equipment extra-vehicular moment ,so the smallest submerge depth should be limited to avoid accidents induced by＆amp;nbsp;cavitation .

关 键 词：涡轮泵 瞬态性能 空化 数学模型 数值模拟 

分 类 号：TH311[机械工程—机械制造及自动化]