A Modeling/Experimental Program for Nano-Energetic Particles

ABSTRACT: An engineering computational simulation tool based on the shrinking core model of nanoparticle combustion is proposed to investigate ignition, combustion and performance of nano-energetic particles in a variety of oxidizing environments, including those found in rockets and air breathing propulsion devices. The computational model will include appropriate models for the bulk, oxide, and gas-phase, including phase changes in the oxide layer with subsequent changes in diffusivity, and will take into account various other physics, such as alloying, coating, and oxide layer treatments. An experimental program will be carried out to aid in model development and for model validation. Validation experiments will be conducted at the University of Illinois shock tube and combustion facilites, and will be conducted under relevant conditions for the application, including at elevated pressures, elevated ambient temperatures, appropriate levels of particle loading, and in relevant gas-phase environments. Multiple methods for measuring combustion time and temperature will be explored, along with hydrocarbon and flame environments, and multiple nanoparticle materials. The commercialization target is the development of a computational model to predict the combustion characteristics of nano-energetic particles in various oxidizing environments. These include those commonly found in rocket propulsion chambers and in air-breathing propulsion devices using traditional fuels such as JP-8 and RP-1. BENEFIT: There is keen interest in nano-energetic combustion research in the U.S. Air Force (at least AFRL-Edwards and AFOSR) and in the Army for energetic material and propulsion uses. The RocSCM code our commercial simulation code modeling the shrinking core method for nano-energetic combustion resulting from this Phase II SBIR -- will facilitate significant scientific advances and understanding of nano-energetic combustion in many different propulsion and energetic applications of interest to the military. RocSCM will ultimately be integrated with the other meso- and micro-modeling codes in the IMSim system (a complementary IllinoisRocstar LLC product for predicting insensitive munitions behavior of energetic materials), portions of which are actively supported by the Air Force (Edwards AFB, Eglin AFB). More broadly, modeling propellant and energetic materials is of interest to DoD agencies, as well as NASA and other commercial producers of energetic materials such as ATK and Aerojet. We maintain working relationships with personnel in all of these organizations, as well as at the Department of Energy National Laboratories, where research into mesoscale modeling of energetic materials is pervasive and ongoing. We believe that these governmental agencies will be interested in the developing and completing the IMSim system, including extension of RocSCM, for propulsion (solid propellant rockets), munitions performance, and safety analyses.