离心泵空化流动数值计算  

Numerical Calculation of Cavitation Flow in a Centrifugal Pump

作　　者：王维军[1] 王洋[1] 刘瑞华[2] 黎义斌[3] 印刚[1] 李贵东[1] 

机构地区：[1]江苏大学流体机械工程技术研究中心,镇江212013 [2]中国能源建设集团江苏省电力建设第三工程公司,镇江212013 [3]兰州理工大学能源与动力工程学院,兰州730010

出　　处：《农业机械学报》2014年第3期37-44,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：“十二五”国家科技支撑计划资助项目(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资助项目(CXLX13_662)

摘　　要：为了研究离心泵内部复杂的三维空化特性，采用改进的空化模型和湍流模型中的Standard κ-ε模型和修正的RNGκ-ε模型，对离心泵内部有、无空化流动进行了计算和分析，得到了设计工况下初生空化、发展空化和严重空化时叶片吸力面和压力面上的压力，并与无空化做了对比，提出了空化初生判定准则，系统划定了离心泵的空化区域。结果表明，随着进口压力的降低，空泡首先出现在叶片进口的吸力面，然后沿着叶片型线运动，形成附着空泡，进而空泡尾迹脱离主流，偏向压力面，堵塞部分流道，最终占据全部流道，使液流断裂；设计工况下初生空化数（σ=0．3067）和严重空化数（σ=0．0281）相差一个数量级；从叶轮子午面上看，空泡首先在靠近后盖板处出现，逐步向前盖板运动，并附着在前盖板圆弧附近；离心泵空化细分为初生空化、临界空化、发展空化、完全空化、断裂空化5个空化过程。The paper aims to deal with the numerical simulation of cavitation phenomena inside the centrifugal pump and analyze the development of cavitation based on improved cavitation model, Standard κ-ε and RNG κ-ε turbulence model. When cavitation flow and non-cavitation flow were simulated and analyzed, the pressure of blades under incipient cavitation, developed cavitation and serious cavitation were gotten. The paper also gave the principle of incipient cavitation and divided the region into five cavitation regions based on bubble relative length. The results show that with the decreasing of inlet total pressure, bubble appears firstly in suction surface of the blade, and then moves along the blade profile, and next forms attached cavitation bubble. After this stage, bubble is gradually out of the mainstream movement and close to the pressure surface. Finally, the flow passage is filled with bubble, which hinders the flow. The number σ = 0. 306 7 of incipient cavitation is a greater dimension hierarchy than that of σ = 0. 028 1 under design condition. Seen from the impeller meridian plane, bubble appears firstly in the near the hub, goes towards forward cover plate, and attaches near the front cover. Cavitation in centrifugal pump is subdivided again into the five stages, that are incipient cavitation, critical cavitation, developing cavitation , complete cavitation, broken cavitation.

关 键 词：离心泵 空化 多相流 初生空化 数值计算 

分 类 号：TH311[机械工程—机械制造及自动化]