Abstract: A DF or HF chemical laser gain generator fabricated by a platelet technique in which internal passages are more easily formed because the generator is made as a stack of thin platelets that are separately etched and then stacked together. The gain generator is water cooled through passages formed in it during the platelet fabrication process. Water cooling results in lower and more uniform operating temperatures and gas pressures, allowing the use of stronger metals which facilitate the elimination of supporting structures that can degrade laser beam quality. The fabrication method allows for the elimination of gas dynamic and thermally induced density gradients which further degrade laser beam quality.

Abstract: A laser weapon system using a high energy deuterium fluoride (DF) or hydrogen fluoride (HF) laser, for which all necessary reactants and other materials are carried on an easily movable vehicle. Reactant gases are stored mixed with a diluent gas, such as helium, for ease of handling and to provide nearly ideal gas behavior. Cooling water for the laser is also employed in a high pressure steam generator that uses diesel fuel and oxygen to produce heat. Apart from a fluorine generator, the system uses only four storage tanks for reactant gases.

Abstract: A DF or HF chemical laser gain generator fabricated by a platelet technique in which internal passages are more easily formed because the generator is made as a stack of thin platelets that are separately etched and then stacked together. The gain generator is water cooled through passages formed in it during the platelet fabrication process. Water cooling results in lower and more uniform operating temperatures and gas pressures, allowing the use of stronger metals which facilitate the elimination of supporting structures that can degrade laser beam quality. The fabrication method allows for the elimination of gas dynamic and thermally induced density gradients which further degrade laser beam quality.

Abstract: A thruster rocket engine throat insert (12) has a thin walled shell (54) made from a high strength, oxidation resistant material. The shell (54) having a throat (48) of reduced cross-section and a radially extending annular stiffening ring (60) located at the throat (48). A casing (56) made from a material having a thermal conductivity at least 10 times greater than that of shell (54) is molded around an outer surface (58) of shell (54) and has a generally cylindrical exterior surface (59). Shell (54) resists yielding and oxidation caused by the extreme temperatures of rocket fuel combustion products passing through the throat insert (12), while the casing (56) acts to efficiently transfer heat from the shell (54).

Abstract: A rocket propulsion system for spacecraft achieves greater economy, reliability and efficiency rocket by incorporating monopropellant RCS thrusters (1a-1f) for attitude control and bipropellant SCAT thrusters (5a-5c) for velocity control. Both sets of thrusters are designed to use the same liquid fuel, supplied by a pressurized non-pressure regulated tank, and operate in the blow down mode. In the propulsion system such station keeping and attitude control thrusters may function in conjunction with a large thrust apogee kick engine, which may also be of the SCAT thruster construction, that uses the same propellent fuel. Hydrazine and Binitrogen tetroxide are preferred as the fuel and oxidizer, respectively. The new system offers a simple conversion of existing monopropellant systems to a high performance bipropellant dual mode system without the extreme complexity and cost attendant to a binitrogen tetroxide--hydrazine bipropellant system.

Abstract: In accordance with the teachings of the present invention, there is disclosed a thruster rocket engine throat insert (12) having a thin walled shell (54) made from a high strength, oxidation resistant material. The shell (54) having a throat (48) of reduced cross-section and a radially extending annular stiffening ring (60) located at the throat (48). A casing (56) made from a material having a thermal conductivity at least 10 times greater than that of shell (54) is molded around an outer surface (58) of shell (54) and has a generally cylindrical exterior surface (59). Shell (54) resists yielding and oxidation caused by the extreme temperatures of rocket fuel combustion products passing through the throat insert (12), while the casing (56) acts to efficiently transfer heat from the shell (54).

Abstract: Disclosed is a low flow, low Reynolds number cavitating venturi. This cavitating venturi includes an inlet for receiving a liquid at an upstream pressure and an outlet for discharging the liquid received by the inlet at a downstream pressure. The liquid passes through a converging portion having a converging sidewall which extends from said inlet, through a throat portion having a throat sidewall and a diverging diffuser portion having a diverging sidewall. The cavitating venturi provides a substantially stable liquid flow rate independent of the downstream pressure up to a downstream pressure at least as high as 80% of the upstream pressure at a Reynolds number of 60,000 or less.

Abstract: In the preferred embodiment of the invention, a cooled bipropellant thruster 70 for controlling the on-orbit position and orientation of a spacecraft is provided. The cooled bipropellant thruster 70 uses a liquid fuel and liquid oxidizer. The liquid fuel is decomposed in a first chamber 72 with a catalytic bed of decomposition material 74 and produces at least one reaction gas, which flows to the second reaction chamber 90. The second reaction chamber 90 is heated by the reaction gas, but is cooled by liquid oxidizer flowing through cooling passages 92, 94, 98, and 102, which brings the oxidizer into a heat exchange relationship with the second reaction chamber 90. During the heat exchange relationship, heat is transferred from the second reaction chamber 90 to the oxidizer and the oxidizer transforms into a gas. The gaseous oxidizer is fed into a second reaction chamber 90 to secondarily react with the reaction gas.

Abstract: In the preferred embodiment of the invention, a cooled bipropellant thruster 70 for controlling the on-orbit position and orientation of a spacecraft is provided. The cooled bipropellant thruster 70 uses a liquid fuel and liquid oxidizer. The liquid fuel is decomposed in a first chamber 72 with a catalytic bed of decomposition material 74 and produces at least one reaction gas, which flows to the second reaction chamber 90. The second reaction chamber 90 is heated by the reaction gas, but is cooled by liquid oxidizer flowing through cooling passages 92, 94, 98, and 102, which brings the oxidizer into a heat exchange relationship with the second reaction chamber 90. During the heat exchange relationship, heat is transferred from the second reaction chamber 90 to the oxidizer and the oxidizer transforms into a gas. The gaseous oxidizer is fed into a second reaction chamber 90 to secondarily react with the reaction gas.

Abstract: The premixed cold reaction CW chemical laser places the secondary injectors which input fuel and/or diluent in the exit walls of the primary nozzle. These injectors are acutely angled thereto and are arranged in rows and are further grouped therein where a first injector inputs a pure diluent, a second group of injectors inputs independently of a third group.

Abstract: A hypersonic wedge nozzle for chemical lasers that has a radially diverging low primary nozzle with a multiplicity of hypersonic wedge type secondary injection wedges at the exit end of the primary nozzle to allow gas flow to become supersonic in the primary nozzle before entering the regions between the secondary injection wedges or the surfaces thereof. Utilization of the large diverging primary nozzle in producing supersonic flow minimizes viscous effects in producing the supersonic flow in a chemical HF or DF laser.

Abstract: The reactants in a chemical laser are mixed to effect a lasing action by expanding one reactant through a relatively large primary nozzle in such a way as to form an expanding reactant flow field whose free expansion is essentially two dimensional in character and occurs predominantly in directions parallel to a given plane (expansion plane) parallel to the flow path of the flow field, and injecting the other reactant into this expanding flow field in such a way that mixing of the reactants occurs by predominantly molecular diffusion of the second reactant into the first reactant flow field in directions transverse to the flow field expansion plane.

Abstract: An inert diluent such as N.sub.2, He, Ar, etc., is injected into the reactant streams emerging from the cavity nozzle of a CW, supersonic, laser to increase the cavity power and lower the cavity temperature by enhancing mixing of the reactant stream while maintaining high pressure recovery.