Simulation of Bulk Evaporation and Condensation in Cryogenic Propellant Tanks using the Energy of Fluid Method

The design of cryogenic propellant storage systems for long duration space missions relies on accurate prediction of tank self-pressurization. Incident solar radiation heats the cryogenic liquids in the tank over time, vaporizing the cryogenic liquid. As the liquid vaporizes, the tank pressure increases. The objective of the current research is to develop a finite volume based Compuational Fluid Dynamic (CFD) model of tank pressurization in reduced gravity using an Energy of Fluid (EOF) method. A commercially available CFD model is significantly enhanced to include the EOF method, which will solve the energy equation in terms of internal energy. Model validation results are presented which include a comparison of temperature and pressure predictions to the data collected during the terrestrial experiments performed by Aydelott and the low gravity experiment conducted onboard the Saturn IB AS203 tank