不同导叶参数对混流泵水力性能的影响

摘要

为探求不同导叶参数对混流泵水力性能的影响,以比转速为438的模型泵为研究对象,在模型试验验证的基础上,采用计算流体动力学方法,以常规导叶设计为基础,在保持其他参数不变的情况下,分别数值模拟计算了4种不同导叶叶片数方案和7种不同导叶片扫掠角度方案的混流泵段水力性能.数值模拟结果表明:改变导叶叶片数对混流泵段外特性影响明显,不同流量下存在不同的最优叶片数,小流量工况运行时,应适当增加叶片数,大流量工况运行时,应适当减少叶片数;不同导叶片扫掠角度对大流量区域影响显著,不同流量存在不同的最优导叶片扫掠角度且随着流量的增大从-16°逐渐偏向+24°;在流量为510L/s时,计算扫掠角度范围内对效率的影响达5.5％.%In order to investigate the influence of guide vane parameters on the hydraulic characteristics of a mixed-flow pump,using a model pump with a specific speed of 438 as a study object under the condition that other parameters remain constant,the hydraulic characteristics of mixed-flow pumps in four schemes of different numbers of guide vane blades and in seven schemes of different sweep angles of guide vane blades were numerically simulated using the computational fluid dynamics method based on model test verification.The results show that the number of guide vane blades has a significant effect on the external characteristics of the mixed-flow pump.Different optimal numbers of guide vane blades exist for different discharges:the number of guide vane blades should be appropriately increased under low discharge conditions,and it should be appropriately reduced under large discharge conditions.The sweep angle significantly influences the hydraulic characteristics in the large discharge area.Different optimal sweep angles exist for different discharges.The optimal sweep angle changes from-16° to +24° with the increase of discharge,and the influence of the sweep angle within the computational range on the efficiency reaches 5.5％ when the discharge is 510 L/s.