On-Demand Gas Generator with Real-Time, Open-Loop Control System for Gel Propulsion

On-demand bipropellant propulsion systems for advanced tactical missiles require on-demand gas generators for pressurization and expulsion. Phase I of this SBIR investigated the feasibility of an open-loop controlled, on-demand gas generator operating in the bootstrap mode. That is, without active control and self powered. Several single-stage and two-stage designs were examined. A single-stage design having a pre-pressurized startup was found to meet all requirements. Bootstrap operation was provided by a novel integral gas generator tank with an opposing dual area piston assembly that furnishes the necessary pressure amplification for bootstrap operation. Simulations confirmed stable operation with all parameters maintained within practical limits and capable of unlimited restarts. This Phase II effort will implement this design in heavy wall test hardware. A test program is planned with cold and hot gas pressurization tests to confirm startup and initial bootstrap operation. A short continuous hot fire test will confirm the functioning of the dual area piston. Finally, a long duration duty cycle test will verify functionality of all components using ganged pistons expelling simulants. This final long duration hot fire test will demonstrate the feasibility and utility of this design approach with a duty cycle having multiple pulses and stop/restarts.