摘要
为探究径向导叶式压出室离心泵叶轮切割后性能的变化,基于N-S方程、标准k-ε湍流模型和SIMPLE算法对MD-280-42×4多级离心清水泵单级叶轮外径切割进行三维湍流数值计算,分析不同切割量下径向导叶式离心泵外特性和内部流动变化。结果表明:在设计工况(Qd=0.078 m3/s)下,随着切割量的增加,径向导叶式离心泵的水力效率、轴功率均呈现下降趋势;在相同小流量工况下,随着切割量的增加,叶轮与导叶间隙和反导叶流道处流动损失逐渐减小,水力效率呈现上升趋势;在相同大流量工况下,随着切割量的增加,正反导叶流道流动均匀性受到较严重破坏,产生了较大的能量耗散,水力效率明显下降。
To investigate the influent of impeller trim on hydraulic performance of the radial diffuser in a centrifugal, the three - dimensional turbulent flow in a cut impeller of a single stage in multi - stage centrifugal pump MD - 280 - 42×4 was numerically simu- lated using a SIMPLE algorithm based on Navier - Stokes equation, and the standard k - ε turbulence model. The external characteris- tic and the fluid flow of the radial diffuser in a centrifugal pump were analyzed. Research results show that with the size of impeller trimmed under the design conditions （Qd = 0. 078 m^3/s） increasing, The hydraulic efficiency and shaft power of the radial diffuser in a centrifugal decline. With the size of impeller trimming under the same small flow raising, the fluid flow of both gap between the im- peller and the radial diffuser and the anti - guide becomes more and more uniform, and the hydraulic efficiency is enhanced in the same case ; With the size of impeller trimming under the same mass flow increasing, the fluid flow of the guide vane and the anti - guide is badly interrupted, and the energy dissipation raises in the both positions. The hydraulic efficiency reduced in the same case.
出处
《西华大学学报（自然科学版）》
CAS
2015年第3期77-82,103,共7页
Journal of Xihua University:Natural Science Edition
关键词
叶轮切割
径向导叶
多级离心泵
反导叶
数值模拟
impeller trim
radial diffuser
multistage centrifugal pump
anti - guide vane
numerical simulation
