Experimental study on refrigeration performance and fluid thermal stratification of thermodynamic vent

Long term storage of cryogens is significant to the future space exploration. Thermodynamic vent is treated as an efficient method to realize the tank pressure control and the efficient storage of cryogenic fuels. In the present study, an experimental rig is built to research the pressurization and refrigeration performance of thermodynamic vent with R123, under the influence factors of initial liquid height, external heat load, pressure control band and circulation flow. Meanwhile, the fluid thermal stratification is investigated for the best experiment condition. The results show that the opening of the throttling orifice and the total circulation flow pipe size should be matched well to achieve the best operation of TVS. Moreover, the circulation flow rate has a direct effect on the tank pressure control and the development of the fluid thermal stratification. Some valuable conclusions drawn from the present study could be applied to cryogenic propellants of space vehicle.