CFD application to depressurization of cryogenic tanks in microgravity

In order to control fluid temperature in cryogenic tanks, it is necessary to handle complex thermodynamics phenomena. For future space launchers, phases containing micro-gravity are responsible for an increased complexity and ask for more complete numerical approaches. One characteristic phase occurring in microgravity in future space launchers is analysed in this paper: depressurisation and liquid movements following gravity perturbation. From the difficulties to perform tests with cryogenic liquid including microgravity in large scale facilities, our numerical methods are validated thanks to test performed on earth. These tests have been performed by the Division des Techniques Avancees - Air Liquide in the framework of the French-German COMPERE program.