【摘要】 为满足低扬程泵站工程建设的需要,采用简单径向平衡流动模型和二维叶栅面元法叶片造型方法设计高比转数轴流泵水力模型。并用RNG k-ε紊流模型对水力模型进行数值分析,分析过程考虑了叶轮叶顶间隙的影响。模型试验表明,设计点相当准确。数值分析在设计点附近精度较好,能满足工程应用的要求,但在非设计工况误差较大。计算还表明,叶轮在正扬程时就出现了负的轴向力,从而解释了立式泵在低扬程运行时的抬机现象。更多还原

【Abstract】 An inverse method based on the model of radial equilibrium equation and 2-D panel method is used to design the axial-flow model pump with high specific speed. The numerical simulation is based on the CFX-TASCflow CFD code solving the 3-D PLANS equations with the RNG k-ε model of turbulence. The multiple frame of reference capability (stage method) is applied to model the interaction between the impeller and guide vane as well as the grid embedding is used to simulate the tip clearance. The experimental results show the design method can assure design characteristic of the pump. A comparison of the calculation and the measurements demonstrates a very good agreement of the head and hydraulic efficiency at design point, but a significant departure at off-design point. The calculation also shows the negative thrust has turned up when the head is still positive, which exactly explain why the impeller is raised at high flow rate.更多还原