低比转数恒扬程泵内部流场数值模拟  

Numerical simulation of low specific speed constant-head pump

作　　者：王洋[1] 印刚[1] 王维军[1] 李贵东[1] 崔宇蕊 

机构地区：[1]江苏大学国家水泵及系统工程技术研究中心,江苏镇江212013

出　　处：《排灌机械工程学报》2015年第1期10-15,共6页Journal of Drainage and Irrigation Machinery Engineering

基　　金："十二五"国家科技支撑计划项目(2011BAF14B01);江苏高校优势学科建设工程资助项目;江苏省研究生培养创新工程项目(CXLX13_662)

摘　　要：应用流场计算软件CFX,采用修正的RNG k-ε湍流模型,数值模拟了5种流量(0.6Qd,0.8Qd,1.0Qd,1.2Qd和1.4Qd)工况下恒扬程泵的内部流场,重点对0.6Qd,1.0Qd和1.4Qd等3种流量工况下叶轮中间流面的压力场以及速度场进行研究,并提取了该3种流量工况下叶片中间流线的载荷进行分析.采用正则化螺旋度Hn对叶轮中间流面以及蜗壳8个断面的涡旋流动进行了分析.模拟结果表明:叶轮出口边存在明显的回流,回流角随着流量的增大而减小;叶片形状对叶片载荷分布规律具有一定的影响;相对于主流运动方向而言,叶间流道内主要是正向涡旋,而蜗壳内部是对称性旋涡,蜗壳内旋涡从隔舌处的断面到螺旋线末端的断面经历了由稳定到不稳定再到稳定的发展过程.The steady flow in a low specific speed constant-head pump is simulated numerically by using ANSYS CFX software with the RNG k-ε turbulence model at five flow rates：0.6Qd,0.8Qd,1.0Qd,1.2Qdand 1.4Qd.The static pressure and velocity fields on the mid-span surface of the impeller at flow rates：0.6Qd,1.0Qdand 1.4Qdare investigated and the blade loading on the mid-span surface are analyzed as well.The normalized helicity Hn is used to analyze the flow conditions on the midspan surface of the impeller and in the eight sections of the volute.The results show that an obvious backflow can be seen at the impeller outlet,and the angle of backflow tends to get small with the increasing flow rate.The blade shape has a certain influence on the blade loading distribution.The forward direction vortexes exist in the impeller passages,while a pair of symmetrical vortexes always occurs in the volute sections.This pair of vortexes experiences a stable,unstable and stable again development process when the fluid particles flow to the eighth section from the cut-water of the volute.

关 键 词：离心泵 低比转数 叶片载荷 涡量 数值计算 

分 类 号：S277.9[农业科学—农业水土工程] TH311[农业科学—农业工程]