Analysis of Cavitation Flow and Energy Characteristics of Space Micro Pump under a Wide Temperature Range

Abstract The space micro pump has a wide temperature range, and it experiences obvious thermodynamic effects during the high-temperature cavitation process, which leads to complex flow characteristics. To evaluate the influence of different temperatures on the cavitation flow within the space micro pump, the shear-stress transport k-ω turbulence model (SST k-ω ) and the Zwart-Gerbera-Belamri cavitation model (ZGB) corrected based on thermodynamic effects were used to conduct numerical simulations of the flow channels within the space micro pump. The physical parameters were coupled with temperature to study the cavitation flow in the space micropump over a wide temperature range, and the influence of the wide temperature range on cavitation flow was revealed. The results showed that at high temperatures, the thermodynamic effects manifested as a reduction in the saturated vapor pressure of the cavitation region, a delay in the development of cavitation cavities, a decrease in the vapor volume fraction, and a reduction in the negative impact of cavitation on the performance of micropumps owing to a decrease in viscosity at high temperatures. Moreover, the inhibitory effect of the thermodynamic effects did not increase simultaneously with an increase in temperature. Furthermore, cavitation increased flow losses, whereas following the temperature increase, cavitation inhibition and a decrease in viscosity worked together to reduce this loss.