High-Pressure Bipropellant Microrocket Engine

The development of high-aspect-ratio, high-precision micromachining in silicon or silicon carbide suggests the feasibility of microfabricated, high-chamber-pressure chemical rocket engines. With high-speed turbopumps and valvesincorporatedontotherocketchip,anumberofpropulsioncyclesarepossible.Suchanengine,approximately 20 ££ 15 £ 3 mm in size, operating at a 125-atm chamberpressure, would produceabout 15 N of thrust using 300-s Isp propellants at a thrust-to-weight ratio of 1000:1. The feasibility of these engines has been investigated, and a liquid-cooled, pressure-fed thrust chamber and nozzle have been successfully designed, fabricated, and operated at a 12.5-atm chamber pressure to further evaluate the concept.