离心泵尾流-射流现象及粗糙度对其影响的分析  

Jet-wake Flow in the Channel of Impeller and the Effect of Surface Roughness on It

作　　者：赵斌娟[1] 王瑜[1] 陈汇龙[1] 侯多华[1] 仇晶[1] 

机构地区：[1]江苏大学能源与动力工程学院,镇江212013

出　　处：《农业机械学报》2014年第9期138-143,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金资助项目(51109094);江苏省高校优势学科建设工程资助项目;航空科学基金资助项目(201328R3001)

摘　　要：为减小叶轮内的流动损失,结合计算流体力学、壁面函数法和等效沙粒粗糙度模型,研究了离心泵叶轮流道内的尾流-射流现象及其受粗糙度的影响规律。对比试验和数值模拟结果,确保了所选计算方法和湍流模型(RNG k-ε模型)能够准确反映内流场的变化。研究表明:在叶轮流道内相对速度W的分布存在明显的尾流-射流规律,且吸力边后盖板附近的边界层厚度较大,尾流区主要在吸力边后盖板附近;在叶轮出口处,尾流区则出现在吸力边的前盖板附近。粗糙度对叶轮流道内湍流的影响较大,对压力边和吸力边相对速度的影响相反。粗糙度对内部流动的影响存在一个过渡值,当粗糙度大于此值时,粗糙度对流动的影响与粗糙度小于此值时相反。随着粗糙度的增加,叶轮出口处相对速度波动的振幅增加。For analyzing the flow pattern and reducing the hydraulic loss, the jet-wake flow in the channel of impeller and how it is influenced by the surface roughness have been studied by coupling computational fluid mechanics and the sand-grain roughness method. The results of experiment and simulation were compared to insure the RNG k - 6 model could reflect the variation of the inner flow. The results indicate that the jet-wake flow was obvious in the channel of impeller and the jet flow appeared mainly nearby the rear shroud of the suction side, while the jet flow appeared in the front shroud at the exit of impeller. The surface roughness of the impeller had a great influence on the relative velocity, and had the opposite influence on the pressure and suction side. The effect of surface roughness on the relative velocity become opposite when the value of roughness was higher than a transitional point. With the increase of the value of surface roughness, the amplitude of the relative velocity at the exit of impeller increased obviously, which was caused by the impeller-volute interaction.

关 键 词：离心泵 粗糙度 尾流-射流结构 叶轮流道 数值计算 

分 类 号：TH311[机械工程—机械制造及自动化]