Numerical Flow Simulation in a Centrifugal Pump at Design and Off-Design Conditions
Numerical Flow Simulation in a Centrifugal Pump at Design and Off-Design Conditions
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DOI：
10.1155/2007/83641
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发表时间：
2007-06
影响因子：
0.9
通讯作者：
K. W. Cheah;T. Lee;S. H. Winoto;Z. Zhao
中科院分区：
文献类型：
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作者：
K. W. Cheah;T. Lee;S. H. Winoto;Z. Zhao
采用三维Navier-Stokes程序，采用标准k-ε双方程湍流模型，对六扭曲叶片离心泵叶轮内部的复杂流动进行了数值模拟。在入口边界处指定不同的流量以预测泵的特性。详细分析了在设计载荷、Qdesign和非设计条件下（Q = 0.43 Qdesign和Q = 1.45 Qdesign）的结果。数值模拟结果表明，在设计点叶轮通道内的流动是比较光滑的，并且遵循叶片的曲率。然而，由于非切向来流条件，在前缘处观察到流动分离。蜗壳内部的流动也发生了明显的变化，在分水角处形成了双涡结构，在蜗壳扩压器处逐渐演变为单涡结构。压力分布是沿沿着逐渐增大的。当离心泵在变流量工况下运行时，叶轮流道和蜗壳内均会产生非定常流动。
The current investigation is aimed to simulate the complex internal flow in a centrifugal pump impeller with six twisted blades by using a three-dimensional Navier-Stokes code with a standard k-ε two-equation turbulence model. Different flow rates were specified at inlet boundary to predict the characteristics of the pump. A detailed analysis of the results at design load, Qdesign, and off-design conditions, Q = 0.43 Qdesign and Q = 1.45 Qdesign, is presented. From the numerical simulation, it shows that the impeller passage flow at design point is quite smooth and follows the curvature of the blade. However, flow separation is observed at the leading edge due to nontangential inflow condition. The flow pattern changed significantly inside the volute as well, with double vortical flow structures formed at cutwater and slowly evolved into a single vortical structure at the volute diffuser. For the pressure distribution, the pressure increases gradually along streamwise direction in the impeller passages. When the centrifugal pump is operating under off-design flow rate condition, unsteady flow developed in the impeller passage and the volute casing.