Abstract: An apparatus for heating fluid includes a tank for holding fluid to be heated, and a fuel wafer in fluid communication with the fluid. The fuel wafer includes a fuel mixture including reagents and a catalyst, and an electrical resistor or other heat source in thermal communication with the fuel mixture and the catalyst.

Abstract: A system and method of cooling a rocket motor component includes injecting a high pressure liquid coolant through an injector nozzle into a cooling chamber. The cooling chamber having a pressure lower than the high pressure liquid coolant. The liquid coolant flashes into a saturated liquid-vapor coolant mixture in the cooling chamber. The saturated liquid-vapor coolant mixture is at equilibrium at the lower pressure of the cooling chamber. Heat from the rocket motor component to be cooled is absorbed by the coolant. A portion of the liquid portion of the saturated liquid-vapor coolant mixture is converted into gas phase, the converted portion being less than 100% of the coolant. A portion of the coolant is released from the cooling chamber and the coolant in the cooling chamber is dynamically maintained at less than 100% gas phase of the coolant as the thrust and heat generated by the rocket motor varies.

Abstract: In some embodiments a propulsion system includes a thrust chamber having an inside wall, an expansion nozzle mounted to the thrust chamber and having an interior and having an exterior, a main propellant injector mounted to the thrust chamber to inject a fluid in the interior of the thrust chamber, the fluid comprising oxidizer, fuel and internal film coolant, the internal film coolant ranging from about 1% to about 5% of the fluid, limited coolant tubing circumscribing the exterior of the expansion nozzle to circulate an external coolant, and an injector mounted to the expansion nozzle to inject the external coolant in the interior of the expansion nozzle, the external convective coolant about 2.5% of the fluid. The system operates at lower temperatures while having conventional amounts of thrust, in which the thrust chamber can be made of thin walls of lower cost conventional metals with simple coolant tube construction.

Abstract: A thruster is provided that makes it possible to reduce and eventually eliminate the toxicity of storable liquid propellant and improve the low-temperature environment adaptability of propulsion system using the storable liquid propellant. The thruster produces thrust by using catalytic decomposition gas obtained by catalytically decomposing nitrous oxide with a nitrous oxide decomposition catalyst.

Abstract: Disclosed is a propulsion system for a spacecraft. The propulsion system includes a supply of oxidizer and at least one nozzle. A conduit fluidly couples the supply of oxidizer and the nozzle. The conduit provides a pathway for oxidizer to flow in a downstream direction from the supply of oxidizer toward and into the nozzle. A pressure regulator is coupled to the conduit and is interposed between the supply of oxidizer and the nozzle, wherein the pressure regulator regulates the pressure of oxidizer flowing through the conduit and downstream of the pressure regulator to a pressure at or below the pressure required to maintain the oxidizer in a gas state to ensure that the any oxidizer flowing through the conduit is in a gas state prior to entering the nozzle. The conduit supplies oxidizer from the supply of oxidizer to a hybrid rocket motor.

Abstract: A monopropellant assisted solid rocket engine of the present invention is comprised of a combination of a solid rocket engine with nitromethane monopropellant injected into the rocket motor. By controlling the rate at which the monopropellant is injected the thrust of the rocket engine can be controlled.

Abstract: A propulsion thruster (10) includes a solid-fuel, liquid-oxidizer main rocket engine (11), a tank (22) of liquid oxygen, and a turbine (32)-driven pump (30) for pumping liquid oxygen to the main engine. A solid-fuel, liquid-oxidizer auxiliary engine (40) has its oxidizer input port (50) coupled to the output (30b) of the turbopump, for generating drive fluids for the turbine (32) of the turbopump. The temperature of the turbine drive fluids is reduced to prevent damage to the turbine, and the mass flow rate is increased, by injecting water from a tank (60) into the drive fluids at the output (48) of the auxiliary engine (40). Starting is enhanced by preventing cooling of the solid fuel by the liquid oxidizer, which is accomplished by applying gaseous oxygen from a tank (90) to the oxidizer input port (50) of the auxiliary engine (40).

Abstract: A system is provided for reducing the emissions of hydrochloric acid (HCl) from solid fuel rockets, especially during ground disposal. An aqueous solution (40, FIG. 2 ) of an alkali metal hydroxide is injected as a mist (50) into the rocket chamber (32) as the rocket fuel (30) is burned. The reaction of the alkali metal with hydrogen chloride (HCl) produces a salt and thereby minimizes the presence of hydrochloric acid in the rocket exhaust. An injected neutralizing material which reduces hydrochloric acid, but which produces less thrust than an equal weight of rocket fuel, can be injected into an operating rocket which carries a payload high above the earth, with the injected material being injected only while the rocket is at a lower altitude when hydrochloric acid is most undesirable. The injected material can be produced by a small auxiliary rocket device (82, FIG.

Abstract: A method for reducing radar attenuation caused by the formation of free etrons in the exhaust plume of a combusting high impulse rocket propellant which comprises contacting a microwave attenuation reducing additive having at least one element selected from the group consisting of Groups IIIA, IVA, VB, VIB, VIIB and VIII of the Periodic Table with said high impulse propellant. A novel propellant composition characterized by its combustion of low microwave attenuation properties. A class of additives useful for reducing the microwave attenuation characteristics of high impulse propellants.