螺旋轴流式多相混输泵叶轮域的能量特性

为了定量分析螺旋轴流式多相混输泵叶轮各区域的能量转换特性,在清水介质和气液两相介质下分别对螺旋轴流式多相混输泵进行数值模拟计算,通过分析叶轮域的能量变化规律来揭示流量和混输泵进口气体体积分数对多相混输泵叶轮各区域做功的影响规律.研究结果表明:叶轮所携带的机械能主要在叶轮中部传递给流体介质,大部分转换成了流体介质的静压能,且从叶轮进口到出口做功能力先增强后减弱;在清水介质下,随着流量的增大,叶轮前半部分做功能力逐渐增强,后半部分做功能力逐渐减弱;在气液两相介质下,随着进口含气率的增大,叶轮做功能力逐渐减弱,且进口含气率主要影响叶轮前半部分做功能力,而对后半部分影响较小.研究结果可为螺旋轴流式多相混输泵过流部件的优化设计提供一定的参考依据.

Energy transfer characteristics of fluid in impeller of helical axial-flow multiphase pump

Numerical simulations were conducted in a helical axial-flow multiphase pump under water single-phase and air-water two-phase flow conditions to quantitatively analyze energy transfer characteristics of the fluids in the impeller, respectively. By demonstrating the energy transfer characteristics in the impeller, the relationships of flow rate and inlet air volume fraction with the work done in diffe-rent regions of the impeller were revealed. The results show that the impeller mechanical energy is mainly transferred to the fluids in the middle region of the impeller, and the most energy transferred is in static pressure. Further, the impeller capacity of doing work firstly increases and then decreases from the impeller inlet to the outlet. Under water single-phase flow conditions, with increasing flow rate the impeller capacity of doing work is gradually enhanced in forepart of the impeller but weakened in rear part. Under air-water two-phase flow conditions, with increasing inlet air volume fraction, the impeller capacity of doing work is degraded gradually, especially for forepart of the impeller, and the capacity in rear part is less affected. These results can provide a reference for the optimal design of flow components of the helical axial-flow multiphase pump.