Investigation on the impeller-diffuser interaction on the unstable flow in a mixed-flow pump using a modified partially averaged Navier-Stokes model

OCEAN ENGINEERING

卷:238

Article

Ye, Weixiang^1,2  Geng, Chen¹  Hachinota, Shinya²  Miyagawa, Kazuyoshi³  Luo, Xianwu¹ 

[1] Tsinghua Univ, Dept Energy & Power Engn, State Key Lab Hydrosci & Engn, Beijing 100084, Peoples R China

[2] Waseda Univ, Dept Appl Mech, Tokyo 1698555, Japan

[3] Waseda Univ, Dept Appl Mech & Aerosp Engn, Tokyo 1698555, Japan

关键词: Mixed flow pump;    Unstable flow;    MSST PANS turbulence model;    Local energy loss;    Rotating stall;    Impeller-diffuser interaction;   

DOI  :  10.1016/j.oceaneng.2021.109756

来源: Elsevier

【 摘 要 】

In this paper, the effect of the impeller-diffuser interaction on the unstable flow in a mixed-flow pump operating under one part-load condition is investigated based on the local energy loss analysis using a modified SST k-omega partially averaged Navier-Stokes (MSST PANS) model. The comparison on the pump performance shows a good agreement between the experiment and simulation. The characteristic curve of the test pump presents a positive slope region, where hydraulic loss increases 90.75% in the impeller and 16.75% in the diffuser. The internal flow analysis depicts that the rotating stall evolution captured in the impeller passages involves larger energy transfer while the separating flow in the diffuser passage involves lower energy transfer. As the impeller blade tailing edge (TE) begins to interact with the diffuser blade leading edge (LE), the vortex attached to the impeller blade TE is cut off into two parts, one of which keeps propagating circumferentially and forms the rotating stall in the impeller, and the other is regarded as the shedding vortex, moving into the diffuser. Further analysis by the Fast Fourier Transform and proper orthogonal decomposition reveals the frequency of rotating stall is 1.49fn, and the frequency of the shedding vortex is 0.53fn.

【 授权许可】

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