According to one contemplated embodiment of the rocket engine invention, water is first pumped from a water tank through a rocket nozzle cooling heat exchanger wherein it is evaporated into said superheated steam. A generator supplies electricity to an electrolyzer that electrolyzes superheated steam into gaseous hydrogen and gaseous oxygen. The gaseous hydrogen and gaseous oxygen is employed for forming an annular curtain of secondary combustion in a divergent rocket engine. The secondary combustion gas surrounds a central thrust of combustion gas produced in an upstream combustion chamber by a primary injection of hydrogen/oxygen supplied from a liquid hydrogen tank and liquid oxygen tank. The rocket liquid hydrogen tank and liquid oxygen tank are pressurized by gaseous hydrogen and gaseous oxygen generated by the electrolyzer.

A propulsion assembly for a rocket includes a propellant tank configured to contain a propellant and an engine comprising a combustion chamber configured to subject the propellant to combustion and generate exhaust gases. The propulsion assembly further includes a supply circuit and an exhaust gas circuit. The supply circuit is disposed between the propellant tank and the combustion chamber, and the supply circuit is configured to supply the combustion chamber with the propellant. The exhaust gas circuit is disposed between the combustion chamber and the propellant tank, and the exhaust gas circuit is configured to convey at least part of the exhaust gases from the combustion chamber to the propellant tank to provide pressurization of the propellant tank.

A satellite includes a housing, a circuit board containing circuitry, a battery electrically connected to the circuit board, a tank, an expandable balloon disposed in the tank, a heater, a valve providing liquid communication between the tank and the heater when in an open position and providing no liquid communication between the tank and the heater when in a closed position, and a nozzle having an orifice in liquid communication with the heater. Operating the satellite includes partially filling the expandable balloon with a gas, loading liquid fuel into the tank, launching the satellite into space, opening the valve to cause the liquid fuel from the tank to pass into the heater under pressure provided by the gas in the expandable balloon, activating the heater to heat and vaporize the liquid fuel into a fuel vapor, and expelling the fuel vaper out of the nozzle.

A supply system for supplying a rocket engine with at least one propellant, the supply system comprising at least one supply circuit able to circulate the propellant, and at least one reservoir in fluid communication with the supply circuit via at least one communication pipe, so that a fluid contained in the reservoir can flow from the latter up to the supply circuit, and vice versa, via said at least one communication pipe, the reservoir being able to contain a volume of gas, and heating means able to vary the volume of gas in the reservoir, the heating means being configured to vaporize the propellant in the reservoir.

A spacecraft structure for transporting propellant to be consumed by a thruster includes storing the propellant in the spacecraft in a solid state during at least a portion of a take-off procedure and supplying the propellant to the thruster in a liquid or vaporous state when the spacecraft is in space.

The flow rate control device includes a main plate corresponding to an inner diameter and including a through hole which is formed at the center thereof and through which a fluid flows, a sub-plate corresponding to a size of the through hole, disposed in front of the main plate, and applied with a pressure of the flowing fluid, and an expansion and contraction flow path formed to connect the through hole and a circumference of the sub-plate to each other and expanded and contracted by the pressure applied to the sub-plate. The expansion and contraction flow path includes a plurality of holes which are formed in a side surface thereof and through which the flow flows, and has a cross-sectional area changed by the pressure to control a flow rate.

A liquid-driven propulsion device includes a first and a second chamber. The first chamber includes a first seal movable or deformable within the first chamber, the first seal being configured to separate a working liquid in the first chamber from a first space having a first pressure. The second chamber includes a second seal movable or deformable within the second chamber and configured to separate a working liquid in the second chamber from a second space having a second pressure. The first and the second chambers are coupled to each other to enable a flow of liquid between the first and second chambers. When the first pressure is greater than the second pressure, the working liquid in the first chamber moves in a first direction and the working liquid in the second chamber moves in a second direction to provide a propulsion force applied to the liquid-driven propulsion device.

Concurrent rocket engine pre-conditioning and tank filling is disclosed. A disclosed example apparatus includes an inlet valve to supply a rocket propellant tank that is associated with a rocket engine with rocket propellant, and a flow director to direct at least a portion of a flow of the rocket propellant from the inlet valve to a chill line of the rocket engine to thermally condition the rocket engine as the rocket propellant tank is being filled with the rocket propellant.

Rocket propulsion systems and associated methods are disclosed. A representative system includes a combustion chamber having an inwardly-facing chamber wall enclosing a combustion zone. The chamber has a generally spherical shape and is exposed to the combustion zone. A propellant injector is coupled to the combustion chamber and has at least one fuel injector nozzle positioned to direct a flow of cooling fuel radially outwardly along the inwardly-facing chamber wall. In addition to or in lieu of the foregoing features, the injector can include an oxidizer piston and a fuel piston that deliver oxidizer and fuel, respectively, to the combustion chamber, in a sequenced manner so that the oxidizer is introduced prior to the fuel.

According to one contemplated embodiment of the rocket engine invention, water is first pumped from a water tank through a rocket nozzle cooling heat exchanger wherein it is evaporated into said superheated steam. A generator supplies electricity to an electrolyzer that electrolyzes superheated steam into gaseous hydrogen and gaseous oxygen. The gaseous hydrogen and gaseous oxygen is employed for forming an annular curtain of secondary combustion in a divergent rocket engine. The secondary combustion gas surrounds a central thrust of combustion gas produced in an upstream combustion chamber by a primary injection of hydrogen/oxygen supplied from a liquid hydrogen tank and liquid oxygen tank. The rocket liquid hydrogen tank and liquid oxygen tank are pressurized by gaseous hydrogen and gaseous oxygen generated by the electrolyzer.