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.

A modulation device for modulating a gas ejection section, the device being for placing in a nozzle upstream from the throat of the nozzle, the modulation device including a plug having a downstream end forming a member for partially obstructing the nozzle throat; and a plug guide having an internal housing in which the upstream end of the plug is present. The upstream end of the plug is suitable for sliding in the internal housing of the plug guide between a first position in which the upstream end of the plug is present in an upstream portion of the internal housing, and a second position in which the upstream end is present in a downstream portion of the internal housing. The upstream end of the plug is held in the first position by at least one retaining element for breaking under the effect of heat.

Embodiments of the present invention generally relate to a vapor retention device and methods of using a vapor retention device to manage propellant for upper stage space vehicles. The use of a vapor retention device, in combination with controlled acceleration, drives liquid propellant from a propellant supply line communicating with an upper stage main engine back into a propellant tank and establishes an insulating liquid/gas propellant interface that prevents the exchange of gaseous propellant across the interface.

A field of vehicles propelled by reaction, and more specifically to a method of suppressing the pogo effect in such a vehicle. A feed system for feeding a reaction engine of the vehicle includes a hydraulic accumulator enabling a selection to be made from among a plurality of predetermined operating levels, each corresponding to a different volume of gas. In the method, if a first reference criterion is not satisfied by the current level, the hydraulic accumulator is ordered to make a transition, preferably to an alternative level selected from among alternative levels for which the first reference criterion is satisfied and for which no hydraulic resonant frequency crosses any current mechanical resonant frequency during the transition.

The invention relates to the field of feeding devices, in particular for feeding rockets on the ground. A feeding device (4) of the invention comprises at least two mutually complementary feeding connectors (5, 6), a breakable connection member (15) connecting these two feeding connectors (5, 6) together and presenting a breakable section (15c) between these two feeding connectors (5, 6), and a force transmission member (16) connected to said breakable section (15c) in such a manner as to transmit a breaking load thereto in order to unlock the connection between the two feeding connectors (5, 6). During unlocking, a breaking load transmitted by the force transmission member (16) thus serves to break the breakable section (15c).

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.

Integrated chemical propellant and cold gas propulsion systems and methods are provided. A storage or fuel tank containing the chemical propellant is pressurized by a pressurant. The chemical propellant is selective passed to a propellant thruster through a first port of the storage tank and a propellant valve. The pressurant is selectively passed to a cold gas thruster through a second port of the storage tank and a cold gas valve. In addition, a pressurant tank can be provided. Pressurant contained within the pressurant tank can be selectively placed in communication with the pressurant contained within the storage tank via a pressurant valve, or can be selectively passed to the cold gas thruster through the cold gas thruster valve. Systems can also include bi-propellant thrusters, with a first and second chemical compounds and volumes of pressurant stored in first and second storage tanks respectively.

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.

A method for managing propellant in a spacecraft is disclosed. The method includes storing liquid propellant in a tank under an operating pressure controlled using a product of chemical decomposition of the propellant. The method may include transferring the liquid propellant out of the tank and chemically decomposing a portion of it using, for example electrolysis. Thus generated one or more gas components may be introduced to the tank to control the operating pressure in the tank.