熔盐泵外特性及内部流动的试验及数值模拟

为了揭示熔盐泵内两相流动的规律，研究了熔盐泵试验方法，得到了熔盐泵的外特性.采用粒子成像测速（PIV）技术测量了蜗舌附近熔盐泵内流动，并对熔盐泵内两相流动进行了非定常数值模拟，阐述了试验结果与模拟结果之间的差别，获得了晶体颗粒在熔盐泵内的体积分数分布，并分析了其演化规律.结果表明:熔盐泵内晶体颗粒体积分数分布较稳定，颗粒集中于叶片吸力面附近.粒径对颗粒在叶轮流道内的积聚影响比较大，粒径越大，颗粒积聚越明显.熔盐泵出口静压周期性波动，波动幅度受叶轮内颗粒体积分数分布影响. 

Experiment and numerical simulation of external performances and internal flow of a molten salt pump

In order to reveal the regularity of two-phase flow in the molten salt pump, an experimental method of a molten salt pump was researched, and the external performances were obtained. The internal flow field near the volute tongue was measured by using PIV (particle image velocimetry) technology. Unsteady numerical simulation of two-phase flow in the molten salt pump was carried out. The differences between experiment and numerical simulation results were elaborated. The distribution of volume fraction of crystal particles was obtained and its evolutional regularity was analyzed. The results show that the distribution of volume fraction of crystal particle is stable in the molten salt pump. In the impeller, particles are accumulated near the suction side of blades. The particle volume fraction is affected significantly by the particle diameter. The larger particle size means more obvious particle accumulation phenomenon. The molten salt pump outlet''s static pressure fluctuates periodically, and the amplitude of pressure fluctuation is affected by the particle volume fraction distribution in the impeller passage.