Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft su...Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft suction box and a siphon-type discharge passage with a vacuum breaker as the cutoff device was developed , which possesses such advantages as simple structure , reliable cutoff , and high energy performance.Taking some pumping stations as the case studies , in the light of the specified operation conditions , the hydraulic optimal design of the shaft-type tubular pumping system was determined and the optimized shape of the system was recommended.The performance prediction based on the computational fluid dynamics methodology was determined and the model test verification was conducted.The results show that the predicted data agree with the experimental head and efficiency so that both methods can be used to determine the performance of a real pumping station.Finally , the in-situ measurements of a pumping station during the commissioning period further verified that the shaft-type tubular pumping station with a siphon discharge passage is of higher efficiency , more reliable and stable.展开更多
转速变换方式对变速过程中混流泵的稳定性有显著影响。该研究以混流泵为研究对象采集了其在不同转速变换方式下的主轴振动和压力脉动信号,然后综合信号特征分析方法和改进的逼近理想解(technique for order preference by similarity to...转速变换方式对变速过程中混流泵的稳定性有显著影响。该研究以混流泵为研究对象采集了其在不同转速变换方式下的主轴振动和压力脉动信号,然后综合信号特征分析方法和改进的逼近理想解(technique for order preference by similarity to ideal solution,TOPSIS)模型研究了变速方式对转速变换过程中混流泵运行稳定性的影响。结果表明:在1/4次方、线性和4次方转速变换过程中,主轴振动数据的正联合峭度占比分别为70%、44%和4%,表明4次方转速变换方式可以有效改善变速过程中主轴受到的冲击振动。4次方转速变换方式引发的变速过程中主轴轴心偏移距离相对最小,表明该转速变换方式下主轴的涡动尺度相对最小。4次方转速变换方式还对变速过程中导叶内部的压力脉动峰峰值有显著的改善作用,同时也降低了叶轮出口处高幅值压力脉动的持续时间。经过对比,4次方转速变换过程中的混流泵稳定性分别比线性、1/4次方转速变换过程中泵的稳定性高6.6%、11.0%。该文研究成果为提高转速变换过程中混流泵的稳定性提供了参考。展开更多
基金support by the 11th Five Year Key Project of China’s National Scientific Supporting Plan(Grant No.2006BAB04A03)the Hydraulic Engineering Project from the Water Resources Department of Jiangsu Province(Grant No.2010023)
文摘Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft suction box and a siphon-type discharge passage with a vacuum breaker as the cutoff device was developed , which possesses such advantages as simple structure , reliable cutoff , and high energy performance.Taking some pumping stations as the case studies , in the light of the specified operation conditions , the hydraulic optimal design of the shaft-type tubular pumping system was determined and the optimized shape of the system was recommended.The performance prediction based on the computational fluid dynamics methodology was determined and the model test verification was conducted.The results show that the predicted data agree with the experimental head and efficiency so that both methods can be used to determine the performance of a real pumping station.Finally , the in-situ measurements of a pumping station during the commissioning period further verified that the shaft-type tubular pumping station with a siphon discharge passage is of higher efficiency , more reliable and stable.
文摘转速变换方式对变速过程中混流泵的稳定性有显著影响。该研究以混流泵为研究对象采集了其在不同转速变换方式下的主轴振动和压力脉动信号,然后综合信号特征分析方法和改进的逼近理想解(technique for order preference by similarity to ideal solution,TOPSIS)模型研究了变速方式对转速变换过程中混流泵运行稳定性的影响。结果表明:在1/4次方、线性和4次方转速变换过程中,主轴振动数据的正联合峭度占比分别为70%、44%和4%,表明4次方转速变换方式可以有效改善变速过程中主轴受到的冲击振动。4次方转速变换方式引发的变速过程中主轴轴心偏移距离相对最小,表明该转速变换方式下主轴的涡动尺度相对最小。4次方转速变换方式还对变速过程中导叶内部的压力脉动峰峰值有显著的改善作用,同时也降低了叶轮出口处高幅值压力脉动的持续时间。经过对比,4次方转速变换过程中的混流泵稳定性分别比线性、1/4次方转速变换过程中泵的稳定性高6.6%、11.0%。该文研究成果为提高转速变换过程中混流泵的稳定性提供了参考。
