In order to study the internal flow field pressure distributions of mixed-flow pump with diffe-rent numbers of impeller blades over time, the unsteady numerical analysis on mixed-flow pump based on LES model is carried out in this study, and external characteristic between two kinds of blade number in mixed-flow pump, inlet and outlet of axial velocity distribution of impeller,time domain and frequency domain response of the pressure pulsation at different monitoring points in the mixed-flow pump were all compared in this analysis. The results show that the inlet and outlet axial velocities are greatly influenced by the number of blades. With the increase of flow rate, the difference value of inlet axial velocity between four blade impellers and three blade impellers decreases gradually, and the latter has higher axial velocity in impeller inlet; apparent periodic variation in time domain graph as well as steady pulse amplitude curves is shown in two kinds of impeller. <i>C</i><sub>p</sub>, the outlet pressure pulsation amplitude of guide blade, tends to 0 while the pressure pulsation in the hub of four blade impeller is aperiodic. The main frequencies near the impeller in mixed-flow pump under three or four blades are both blade frequency. Pressure pulsation frequency domain amplitude is greater in three vane impeller than in four vane impeller. The results are of significant reference for design optimization and revealing the unsteady internal flow characteristics with different blade numbers of mixed-flow pump.
JI Lei-Lei,LI Wei,SHI Wei-Dong et al. Influence of different blade numbers on unsteady pressure pulsations of internal flow field in mixed-flow pump[J]. Journal of Drainage and Irrigation Machinery Engin, 2017, 35(8): 666-.