Advanced Solid Ramjet Fuel

The potential for solid fuel ramjets (SFRJ) has been demonstrated over the last 40 years. SRFJ"s have significantly higher impulse than rockets (Isp>1200 sec) making them a competitive solution for long range applications such as missiles, missile interceptors, high speed transport and space vehicle stages. Increasing the regression rate and the energy density of the fuel further improves the advantages of a ramjet by allowing for increased thrust and Isp. In order to increase the solid fuel regression rate as well as increase propellant energy density in SFRJ"s GTL proposes the construction of a 3D printed hybrid fuel grain. This method uses additive manufacturing processes to build a complex fuel grains with advanced features which increase regression rate and energy density. In addition, metal and inert oxidizer concentrations can be included with in the 3D print allowing for spatially varying properties. Finally, nearly all propulsions systems experience combustion instability in development. GTL"s unique capabilities will be leveraged to improve the stability characteristics of the hybrid fuel grain.