Influence of impeller specific speed onhydraulic performances and pressurefluctuations in mixed-flow pumps
FU Yanxia,JIA Qi,SHEN Yang,PACE Giovanni
School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; Zhenjiang Fire and Rescue Division, Zhenjiang, Jiangsu 212000, China; Sitael S.P.A., Pisa 56121, Italy
摘要 A series of steady and unsteady numerical calculations of the internal flow in mixed-flow pumps with three(3)different specific speeds were carried out based on the N-S equation coupled with the standard k-ε turbulence model under different operating conditions to investigate the relationship between the impeller specific speed and the pump performance as well as pressure pulsations. Meanwhile, the pump performance and pressure pulsations inside the mixed-flow pump with three(3)different specific speeds were also analyzed and compared with the corresponding test data. From the results, the averaged deviations between the predicted and tested head among different impellers are below 5%, and with respect to the equivalent impeller specific speeds of 280 and 260, the values are 4.30% and 3.69%, respectively. For all the impeller schemes, the best efficiency point of the mixed-flow pump was found at the flow rate of 120%Qd and the higher head deviation occurs at lower flow rates. Especially, it can be found that the specific speed has a slight effect on the pressure fluctuation in the impellers. Eventually, it was determined that the pump performance curves calculated by nume-rical simulations have good agreement with the relevant experimental results, which verifies that the numerical methods used in the present study were accurate to a certain extent. Furthermore, the results also provide some references to the pressure pulsation analysis and the performance improvement of the mixed-flow pump design.
FU Yanxia,JIA Qi,SHEN Yang,PACE Giovanni. Influence of impeller specific speed onhydraulic performances and pressurefluctuations in mixed-flow pumps[J]. 排灌机械工程学报, 2023, 41(10): 981-987.