High-Slope High-Specific Impulse Propellants for Throttleable Solid Rocket Motors

With the ongoing advancement of the controllable solid rocket motor technologies (materials, actuation, casings, etc.) IM compliant increased burn rate, rate exponent, specific impulse propellants are required to maximize motor performance at all demanded thrust levels. Development of such propellants requires precise optimization of its ingredients to meet all requirements. CFD Research has teamed up with Purdue University to accelerate the formulation, development and proof of concept test and evaluation of such propellants. Phase I will focus on extensive use of machine learning and thermodynamic-based analytical techniques for rapid high-throughput screening of propellant formulations that meet requirements. This modeling guided screening will significantly reduce the cost of Phase I development while enhancing the probability of success. Five screened formulations will be produced at a laboratory scale and characterized by Purdue. The burn rates will be measured at ten different pressures in a Windowed Crawford Bomb to compute pressure exponents. The density, impact and friction sensitivity will also be measurements. During Phase II CFD Research and Purdue will partner with Northrop to scale up the most promising propellant formulations. The pressure exponent and specific impulse of each scaled up propellant will be measured, and the most promising propellant will be evaluated. Numerous other industry standard sensitivity tests will be completed to ensure the most promising propellant is IM compliant, Class 1.3, and possesses extended shelf-life and survivability to -40oC. Approved for Public Release | 25-MDA-12052 (27 Mar 25)