Chill-down Characteristic Modeling of a Cryogenic Propellant Supply Line

Abstract

The transfer line of cryogenic propellant needs to be precooled to make sure that the propellant supply line is always filled with liquid during normal operation. This paper aims to precisely predict the precooling process of cryogenic propellant supply line and identify the governing parameters which affect the line chill-down time. SINDA/FLUINT, a thermal analysis and simulation tool, was used to simulate the line chill-down process of cryogenic liquid. In order to validate the simulation model, the simulation results were compared with the experimental data in an initial propellant supply condition of 250 kPa, 77K subcooled state from LN2 buffer tank. From the simulation results, gravity and supply fluid pressure were identified as important parameters to determine the chill-down time, and their sensitivities are also analyzed in the simulation.