Performance study on a partial emission cryogenic circulation pump with high head and small flow in various conditions

Abstract

A partial emission liquid hydrogen circulation pump was developed to meet an application requirement of small flow and high head in a cryogenic system. Experimental study on prototype pump with liquid nitrogen based on the similarity theory for hydraulic performances such as head, power and efficiency curves were carried out in the cryogenic test platform, which was specially designed and constructed to test performance characteristics for cryogenic fluid in the absence of cavitation and aerial binding.By analyzing the experimental data on the basis of similarity conversion, the results demonstrated theoretically that the pump could achieve performance levels, that is, at the rated condition, head of 125 m, power of 210 W and efficiency of 45%, if liquid hydrogen was used as working fluid finally.To validate the liquid hydrogen pump design and clarify the pressure and velocity effect on internal flows of the pump, a numerical simulation on the Reynolds-averaged Navier-Stokes combined with the RNG k-ε turbulence model accounts for three dimensional unsteady flows was applied for getting the pump hydrodynamic performances in all various conditions. Comparison of the performance curves of numerical simulation with test results showed that, at the rated condition point, the head, power and efficiency was 138.5 m, 220 W and 45% respectively. It was proved that the calculating results was in accordance with experimental data well. Feasibility of the model had been validated to a certain extent.