摘要
在传统方法中研究者主要采用大功率、大直径、低轴转速的动力装置来提升喷水推进泵的性能,但是降低叶轮轴转速,会导致中心流域叶轮上流速较低,做功效率下降。为了解决此问题,我们设计了一种并联结构的双涵道喷水推进泵。通过数值模拟方法对双涵道泵水力性能进行初步研究,以单泵的计算方法先研究各自的水力特性,确立最优涵道比。绘制外泵时应该研究合适的轮毂比,考虑中空对轮毂强度的影响,通过计算抗扭截面模量得到外泵尺寸。在最优涵道比下,对泵进口及喷管进行优化以提高其水力性能,并为此类推进泵的设计提供参考。研究发现,当内外涵道比为0.45时,流量增幅最大,约为9%。在最优涵道比下,确定合适的进口段及出口喷管结构,定义无量纲参数喷管收缩系数K,发现喷管收缩比为0.3的双涵道泵拥有较好的水力性能。双涵道喷水推进泵在流量推力方面有显著提升,但是在扬程效率方面有待进一步优化。
In the traditional way,researchers tend to use power plant with high power,large diameter,and low shaft speed to improve the performance of water-jet propulsion pump.However,reducing the shaft speed of impeller will lead to low flow velocity and low working efficiency on the impeller in the center.In order to solve this problem,a parallel structure of double-duct water jet propulsion pump was designed.By the numerical simulation method,the hydraulic performance of double-duct pump was preliminarily studied,and the hydraulic characteristics of each pump were studied by calculating single pump to determine the optimal duct ratio.When drawing the external pump,its specification was obtained by figuring out the reasonable tip hub ratio,considering the influence of hollow on the wheel hub strength,and calculating the torsional section modulus.With the optimal duct ratio,the inlet and nozzle were optimized to improve their hydraulic performance and provide reference for the design of this kind of propulsion pump.When the internal and external duct ratio was 0.45,the flow increased to the maximum extent,that is about 9%.With the optimal duct ratio,when the appropriate inlet and outlet nozzle structures were determined and the dimensionless parameter nozzle contraction coefficient K was defined.It was found that the double-duct pump with a nozzle contraction ratio of 0.3 had better water conservancy performance.The flow power of double-duct water-jet propulsion pump is significantly improved,but the lift efficiency needs to be further optimized.
作者
韩伟
李中恒
韩阳
胥丹丹
郭威
Han wei;Li Zhongheng;Han Yang;Xu Dandan;Guo Wei(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Key Laboratory of Fluid machinery and Systems,Gansu Province,Lanzhou 730050,China)
出处
《甘肃科学学报》
2020年第5期80-87,共8页
Journal of Gansu Sciences
基金
国家自然科学基金项目(51669012)。
关键词
双涵道泵
喷水推进
最优涵道比
喷管收缩系数
Double-duct pump
Water-jet propulsion
Optimal duct ratio
Nozzle contraction coefficient
