Prediction of Ignition Delay of Hypergolic Energetic Ionic Liquid

In this program, CFDRC will develop a tool-kit for prediction of ignition delay of hypergolic energetic ionic liquids (EIL). Recently EILs have attracted considerable attention as next generation bipropellants to replace toxic monomethylhydrazine (MMH)  Due to their low vapor pressures, they are safer to handle and transport, and more environmentally friendly than MMH. Accurate prediction of the ignition delay time of EIL with oxidizers, such as IRFNA, is critical to the development of new hypergolic EIL. In Phase I, CFDRC will evaluate two techniques, Quantitative Structure Property Relationship (QSPR) and Artificial Neural Network (ANN). We will select a number of descriptors that could potentially exhibit a strong correlation with ignition delay. The descriptors can be constitutional, structural, electrostatic and/or quantum mechanical. A QSPR and trained network will then be established with the ignition delay time and the descriptors. The correlation and network will be validated, and performance of these two methods will be critically analyzed. Additionally, we plan to initiate the physics-based detailed kinetics method with an aim to reveal the bottle-neck of hypergolic reaction which would help design new EIL with improved ignition delay. In Phase II, we plan to refine the model, develop a user-friendly tool-kit and continue extensive work on detailed kinetics to gain understanding of hypergolic reaction. BENEFITS: Development of proposed tool-kit will predict the ignition delay of energetic ionic liquids at the early stages of development (prior to their laboratory synthesis). This will save significant amount of time and cost of development of new hypergolic fuel. Since the new hypergolic ionic liquids will replace MMH, DoD and NASA will benefit from this work.