This work attempts to establish the vision for Computational Fluid Dynamics as a rocket injector design tool. Simulations of a 5-kN thrust liquid rocket engine swirl atomizer, under cold flow conditions, using an open source CFD code is the immediate goal of this research. The governing equations are solved based on the laminar volume of fluid (VOF) interface capturing method. The oxidizer and fuel injector elements were analyzed for discharge coefficient, spray-cone angle, liquid film thickness as well as other design related parameters. Results from cold flow experiments and particle image velocimetry (PIV) are compared to the predictions of the swirl models and the numerical results. The VOF model was able to predict the spray angle with reasonable confidence, however, a deviation of 25% was observed in the mass flow rate and discharge coefficient. Although the laminar model has proven inadequate, it constitutes a good starting point in the procedure needed to assess swirl injector performance. Work is currently in progress to evaluate Reynolds Averaged (RANS) and Large Eddy (LES) turbulent numerical models.
Liquid oxygen and liquid methane rocket engines are leading candidates for a variety of space missions, including the critical role of main descent propulsion of planetary landing spacecraft. Particular mission characteristics in this context may dictate the use of propulsion systems with deep-throttling capability and able to deliver good performance over the entire thrust range. A well-known injector type with favourable combustion stability, heat transfer and performance characteristics is the pintle injector. This atomizer has been tested with a variety of propellants, such as monomethyl hydrazine/nitrogen tetroxide, fluorine/methane and oxygen/hydrogen. However, characterization employing liquid oxygen and liquid methane is relatively scarce. In order to obtain relevant parametric performance data at nominal and off-nominal conditions, a miniature cryogenic test stand operating with LO 2 /LCH 4 propellants was designed and built. Presented here are the results of a systematic study to determine the uncertainty of measured and calculated parameters defining pintle injector performance. The approach used for the measurement of relevant quantities such as thrust, propellant flow rates, temperature and pressures is discussed and a description of the methodology used in the error analysis is given. Final values of uncertainty in characteristic velocity efficiency are presented for different pintle injector configurations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.