| 摘要: |
| 采用Navier-Stokes方程和Spalart-A llm aras湍流模型对8叶片和24叶片的高速复合离心叶轮内部的流动进行了数值模拟,对小流量和设计点两种工况进行了计算和对比分析,得到了叶轮内的速度和压力分布;发现具有4长、4中、16短的24叶片的复合叶轮内部及出口的速度分布比4长4中的8叶片的叶轮更均匀;而且中、短叶片对液流有加功作用,可以增加叶轮出口吸力面的压力,有效阻止液流的脱流。通过实验和数值模拟,验证了叶轮流道里的回流是影响低比转速离心泵效率和小流量不稳定的一个重要因素;采用具有中、长、短的闭式复合叶轮离心泵适合用来输送小流量、高扬程的液态介质。 |
| 关键词: 涡轮泵 离心泵 叶轮 数值仿真 |
| DOI： |
| 分类号:TH311 |
| 基金项目:国家自然科学基金资助项目(50576088);浙江省自然科学基金资助项目(R503170);教育部博士点基金资助项目(20030335009);浙江省重大科技攻关项目(2003C14002) |
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| Numerical simulation of inner flow field in centrifugal impeller with long,middle and short blades |
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CUI Bao-ling,ZHU Zu-chao,CHEN Ying,LIN Yong-gang
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1.State Key Laboratory of Fluid Power Transmission and Control,Zhejiang Univ.,Hangzhou 310027,China;2.Laboratory of Multi-Phase Fluid Transmission Technology,Zhejiang Univ.of Sciences and Technology,Hangzhou 310018,China
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| Abstract: |
| The Navier-Stokes equations and the Spalart-Allmaras turbulence model are adopted to simulate the inner flow field in high-speed complex centrifugal impellers with eight and twenty-four blades,respectively.The relative velocity and pressure distributions are analyzed and compared in the flow channel of two impellers under small-flow and design-flow condition.It is found that the velocity distribution of inner channel and outlet in complex impeller with four-long,four-middle,sixteen-short blades are more uniform than that with four-long,four-middle blades.And the middle and short blades can increase the suction-side pressure and prevent liquid separation from suction side in complex impellers.Through the experiment and simulation,it is validated that the back flow in impeller channel is a key factor which affects the efficiency and small-flow instability of low-specific centrifugal pump and centrifugal pump with closed complex impeller with long,middle and short blades can be used to deliver small-flow high-head liquid media. |
| Key words: Turbopump Centrifugal pump Impeller Numerical simulation |
