Abstract:Unsteady characteristics of blade hydraulic moment in centrifugal pumps are key factors having strong influence on pump operation. But there is few literature on the unsteady hydraulic moment currently. Thus, with CFD technology, the 3D unsteady flow numerical simulations were executed on a model of XS50—160/7.5 pump for capturing the flow character inside the impeller under 5 different operation conditions. And an experiment has been done for verification of the validity and accuracy. The hydraulic moment fluctuation and the pressure fluctuation on blade surface under 5 different operation conditions were obtained with the simulation. The result of the simulation showed that the blade passing frequency plays a dominant role in the fluctuation of the hydraulic moment at design and off-design conditions under various operating conditions. Meanwhile, the rotating frequency of impeller plays a dominant role in the pressure fluctuation in the impeller at design and off-design conditions. When the frequency is higher than the blade passing frequency, the strength of hydraulic moment pulsation and pressure pulsation on the surface of blade are both relatively weak. At design point, the minimum RMS of the hydraulic moment fluctuation occurred. With the deviation from the design point, the RMS value goes higher. The RMS values at low flow rate condition and at high flow rate condition are almost symmetrically distributed about the design point. The pressure fluctuation in the pressure surface of the blade is stronger than that in the suction surface,that in the outlet zone is stronger than in the inlet zone.
郭义航, 袁寿其, 骆寅, 孙慧. 基于CFD的离心泵叶片水力矩非定常特性[J]. 排灌机械工程学报, 2016, 34(6): 470-476.
GUO Yihang, YUAN Shouqi, LUO Yin, SUN Hui. Unsteady characteristics of blade hydraulic moment in centrifugal pumps with CFD. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(6): 470-476.
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