Gaseous, Liquid, and Gelled Propellant Hypergolic Reaction Mechanisms

Contemporary storable hypergolic bipropellants such as MMH and IRFNA are desirable for use in military rocket applications due to their high specific impulse, no separate ignition system, and to actively control engine thrust. There is also great interest in safer munitions using gelled and lower-toxicity propellants. Unfortunately, the computational tools needed to accurately predict performance with these propellants do not yet exist, costing a great deal of time and money in testing and redesigning under-performing hardware. A validated, modular, multi-phase, chemically reacting Computational Fluid Dynamics (CFD) code capable of accurately simulating gelled propellant ignition and combustion could therefore substantially decrease the cost of developing new IM-compliant weapons systems. We propose to develop such a code employing new reaction chemistry mechanism reduction techniques, non-Newtonian gel atomization, and spray vaporization and solid-particle combustion sub-models incorporated into an existing multi-phase reacting flow CFD code. Success in this effort will allow us to characterize engine performance with gelled propellants and accurately predict ignition delays in engine hardware, decreasing the risk of energetic disassemblies during development. The understanding gained could also help design a relatively simple bench-scale test for gel propellants instead of using full-scale engine hardware, making the screening of lower-toxicity and alternative propellants much more efficient.