Graduate Student Project to Analyze Increase the Range of a Tactical Missile

The Rocket Propulsion II class at The University of Alabama in Huntsville incorporates a design project that integrates course skills into a notional mission design project. This paper describes the course setup, the project technical approach, and recent results for the solid-propellant-boosted, solid-fuel ramjet design project. The students evaluated different candidate solid fuels for an air-breathing ramjet concept. They developed a computer code that calculates the recovery properties of the inlet air, combustion chamber thermochemical properties, and inlet/nozzle performance into a flight simulation to predict overall trajectory performance. They also developed a notional all solid propellant vehicle that had the same internal volume constraints that flew a reference mission for comparison. The SFRJ vehicle augmented the range by 155% to 170% % compared with the all-solids system for all ramjet fuels in initial comparisons. An additional study that parametrically reduced the ramjet fuel regression rate, augmented the missile range from 250% to 290% compared to the all-solids configuration. The results show that, for the notional configuration and fuels evaluated, reducing the fuel regression rate by 40 -50%, shifts the air-to-fuel ratio to a favorable specific impulse, and significantly augments the range of the ramjet when compared to a total solids system or a ramjet system with higher regression rate fuels.