Real Fluid Modeling of Multiphase Flows in Liquid Rocket Engine Combustors

Abstract

The characteristics of propellant mixing near the injector have a profound effect on liquid rocket engine performance. Injector element geometry and propellant momentum are the only parameters available to control such mixing. A multiphase flow combustion model utilizing propellant real-fluid properties was developed to predict the mixing and thermal environment created by element configurations. The multiphase model was incorporated into a mature computational fluid dynamics code that can be used to simulate the flowfield near the injector and to analyze the combustion chamber and nozzle wall heating. The validity of the present model and code was investigated by comparing predictions to test data for two liquid oxygen/gaseous hydrogen unielement shear coaxial injector and two cryogenic nitrogen jet injection experiments. These simulations and those of several other investigators were critically compared at the 2nd International Workshop on Rocket Combustion Modeling. Based on these comparisons, it appears that the present model is a good, computationally efficient approximation of liquid rocket injector flows for both subcritical and supercritical spray combustion.