Modelling and Simulation of Flash Evaporation of Cryogenic Liquids

Abstract

AbstractRocket engine manufacturers attempt to replace toxic, hypergolic fuels by less toxic substances such as cryogenic hydrogen and oxygen. Such components will be superheated when injected into the combustion chamber prior to ignition. The liquids will flash evaporate and subsequent mixing will be crucial for a successful ignition of the engine. We now conduct a series of DNS and RANS-type simulations to better understand this mixing process including microscopic processes such as bubble growth, bubble-bubble interactions, spray breakup dynamics and the resulting droplet size distribution. Full scale RANS simulations provide further insight into effects associated with flow dynamic such as shock formation behind the injector outlet. Capturing these gas dynamic effects is important, as they affect the spray morphology and droplet movements.