Abstract: A thruster nozzle (24) includes a throat (28) and a nozzle end portion (30) that is integral with the throat. The nozzle end portion includes an outer wall (32) that has a plurality of circumferentially-disposed nozzle features or connectors (34). A brace (26) may be disposed at least partially around the thruster nozzle and mated with the nozzle features to restrict relative movement between the thruster nozzle and the brace. The brace may be attached with a vehicle body (22) of a vehicle.

Abstract: A valve assembly includes a valve body, a first spring seat disposed within the valve body, a preload spring disposed within the valve body and mated with the first spring seat, and a second spring seat disposed within the valve body and mated with the preload spring. The second spring seat is adjustably mated to the valve body.

Abstract: A fragmenting nozzle system includes a first nozzle at least partially disposed within a second nozzle. The first nozzle includes an ablative shell, a syntactic foam support disposed between the ablative shell and the second nozzle, and an ignition system disposed at least partially within the syntactic foam support. For example, the ignition system is operable to generate a controlled-energy deflagration pressure wave that fragments the first nozzle but not the second nozzle.

Abstract: An end-burning grain of a solid rocket motor or other gas-generating device is supplemented with one or more sticks of high-burn-rate propellant embedded in a matrix of a relatively low-burn-rate propellant. The sticks increase the burning surface area as the grain burns by forming conical indentations in the surface.

Abstract: A turbopump machine includes a housing, a shaft rotatably supported in the housing on a set of bearings, an axial pump coupled with the shaft, a circumferential discharge volute fluidly coupled with the axial pump, and a turbine coupled with the shaft. The turbine includes a blade row disposed in an axial turbine flowpath that has an axial turbine flowpath discharge that is fluidly coupled with the circumferential discharge volute. A cooling passage is disposed between the housing and the shaft about the set of bearings. The cooling passage has a cooling passage discharge that is fluidly coupled with the circumferential discharge volute. The cooling passage discharge is adjacent the axial turbine flowpath discharge. A seal isolates the cooling passage discharge from the axial turbine flowpath discharge.

Abstract: A rocket motor (20) includes a nozzle (22) and a solid propellant section (24) in communication with the nozzle. The solid propellant section includes a first energetic grain layer (38, 32) that has a top surface and a bottom surface, and a second energetic grain layer (40, 44) that has a top surface and a bottom surface. The second layer is located on top of the first layer. The bottom surface of the second energetic grain layer partially abuts the top surface of the first energetic grain layer, and the bottom surface of the second energetic grain layer and the top surface of the first energetic grain layer define a region (46, 48) therebetween. A powder energetic (49) is disposed in the region.

Abstract: A valve assembly includes a housing (22) that has a fluid input (24) and a fluid output (26). A pintle (30) is disposed in the housing, and an actuator (36) is operatively coupled to move the pintle. The pintle includes a passage (32) that fluidly couples the fluid output with a pressure balance volume (34) located between the pintle and the housing adjacent the linear actuator. A controller (38) is electrically connected with the actuator, and there is a variable flow area (40) from the fluid input to the fluid output that is defined between the pintle and the housing.

Abstract: A propulsion system according to an exemplary aspect of the present disclosure includes, among other things, a pressurant selectively released from a pressure tank to drive a pump to sustain propellant flow for main combustion.

Abstract: A propellant includes a binder system that has a polybutadiene component, a polytetrahydrofuran component, and an anti-oxidant component. In an example, the propellant includes a solid oxidizer, a solid fuel, and a binder system that holds the solid oxidizer and the solid fuel together. The binder system includes a polybutadiene component, a hydrocarbon diluent component of a higher level of saturation than the polybutadiene component, and an anti-oxidant component.

Abstract: A method includes forming at least one fragment wrap of a fragmentation structure by providing at least one flexible fragment strand that includes a plurality of discrete fragments held together in a pattern by a flexible media, and applying the at least one flexible fragment strand around a core piece to form the at least one fragment wrap.

Abstract: A munition includes a composite case, a blast cone housed by the composite case, a grenade aft of the blast cone and housed by the composite case, a first attenuator forward of the blast cone, and a second attenuator aft of the blast cone and forward of the grenade.

Abstract: A monopropellant includes 30-70% by weight of an oxidizer including hydroxylammonium nitrate, 5-50% by weight of a fuel, and a burn rate modifier in a non-zero amount of up to 3% by weight. The burn rate modifier can be selected from vanadium salts, iron salts, and combinations thereof. The monopropellant is a stable liquid between ?20 C and 100 C at ambient pressure.

Abstract: A process of generating a gas includes providing an encapsulation of reactive metal particles, releasing the reactive metal particles from the encapsulation, mixing the reactive metal particles in turbulent water, reacting the reactive metal particles in the turbulent water to generate hydrogen, cooling the turbulent water and the hydrogen with water jets, separating solids and liquids from the hydrogen, and providing the hydrogen to an electrochemical cell.

Abstract: A thermal stand-off includes a rigid thermal stand-off section within a spatial region that extends along a distance between a first location and second, opposed location. The rigid thermal stand-off section includes a tortuous solid-wall thermal conduction path that extends from the first location to the second location. The tortuous solid-wall thermal conduction path is longer than the distance of the spatial region. The tortuous solid-wall thermal conduction path can include a tensile spring constant that is greater than a maximum tensile spring constant of a coil spring that fits in the same spatial region and is formed of the same material composition. The tortuous solid-wall thermal conduction path can include an antegrade section and, relative the antegrade section, a retrograde section.

Abstract: An additive manufacturing process includes pressurizing and heating a slurry, flowing the pressurized heated slurry through a nozzle, and depositing the slurry in a predetermined pattern.

Abstract: A selectable ramjet propulsion system for propelling a rocket or missile includes a gas generator adjacent a booster. A frangible diaphragm is disposed between the gas generator and the booster. The booster and fuel gas generator can be operated in normal sequence, or operated at the same time in order to increase the thrust produced for short-range missions. A logic circuit contained on the rocket or missile determines a time to rupture the frangible diaphragm based on whether or not the distance to the target exceeds a threshold distance.

Abstract: A method for the manufacture of a composite fragmenting material having exothermic properties includes the steps of packing a mold with preformed metal fragments; filling interstitial spaces surrounding the metal fragments with a reactive metal powder to form a mixture; and then sintering the mixture at a temperature effective to both coat the metal fragments with the reactive metal powder and to bond the metal fragments together. In one embodiment the composite fragmenting material is formed into a nosecone for a warhead.

Abstract: A selectively submersible vessel includes a combustor, a Stirling engine thermally coupled with the combustor, an electric generator mechanically coupled with the Stirling engine, a rechargeable battery electrically connected with the electric generator, a compressor electrically coupled with the rechargeable battery, a ballast tank fluidly coupled with the compressor, a snorkel fluidly coupled with the compressor, a controller electrically connected with the rechargeable battery, at least one sensor electrically connected with the controller, a data storage device electrically connected with the controller, and a data communications device electrically connected with the controller.

Abstract: A circuit (400, 700, 800) comprising: a first power source (402) supplying first current to a load (470) during a first Period of Time (“PoT”); a second power source (416) supplying a second current to the load during a second POT; a Unidirectional Current Valve (“UCV”) in series with the first power source; a current detector (420, 702, 802) in series with the UCV (422); and a switch (424) in parallel with a series combination of the current detector and UCV to bypass the UCV during the second PoT. The current detector determines whether the second period of time has commenced and whether the switch has closed.

Abstract: An article includes a vessel, a vent connected to the vessel, and a heat flux-responsive plug disposed in the vent and thermally isolated from the vessel. The heat flux-responsive plug has a material selected based on a phase change characteristic.