Characterization of HAN-based Dense Green Oxidizer Formulations with Solid Hypergolic Mixtures Progress Update

Traditional hypergolic formulations often possess hazards and qualities such as being carcinogenic and issues with vapor pressures, making them less attractive for future systems. The propulsion industry has been innovating towards hypergolic propellants that are environmentally friendly, less hazardous, and do not possess storability issues. Hypergolic propellants are of significant value and interest to the propulsion industry due to their ability to self-ignite and have multiple ignitions, thus increasing robustness and reducing complexity in engine designs. Recent focus on monopropellants and dense liquid oxidizers based on hydroxylammonium nitrate (HAN) can offer solutions to these issues. This study focuses on optimizing ignition delays and tailoring reaction rate of solid hypergolic materials with green oxidizer formulations through the use of combinations of hypergolic powders, nanoparticle metals and fuels. We are also investigating how consolidating such mixtures (possibly including binder additive) into a larger-scale solid will allow control of energy release rate and result in a form factor more suited for potential applications.