Design of Two-Phase Injectors Using Analytical and Numerical Methods with Application to Hybrid Rockets

Overview: Designed a hybrid rocket engine’s injector, creating MATLAB and OpenFOAM CFD simulations, executed on HPC cloud clusters, achieving 3.9% error in simulating two-phase N₂O mass flow. Results published in the AIAA Propulsion and Energy Forum proceedings and used as a resource in Stanford’s graduate-level Advanced Rocket Propulsion course

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Abstract: Liquid injectors under certain conditions may experience cavitation, resulting in two-phase flow which complicates their design and analysis as traditional mass flow rate models are invalid. We evaluated a wide range of analytical models from the literature and concluded that they fall short of a definitive prediction of two-phase mass flow rate.

We addressed this problem by proposing a model capable of predicting mass flow rate and critical pressure with an average error of 3.9%. CFD simulation results using different numerical approaches are presented. An Euler-Euler-VOF hybrid solver predicts mass flow rate with an average error of 3.6%. A design methodology incorporating the analytical and CFD models is presented and used to design a two-phase axial injector for a N₂O-Paraffin hybrid rocket engine.