Abstract: The invention relates to a method of manufacturing an enclosure containing hot gases cooled by transpiration. The enclosure comprises a porous wall and means for applying a cooling fluid to the outside face of the porous wall to cause a flow of cooling fluid to pass through the porous wall by transpiration. The cooling fluid application means is formed by disposing a plurality of cooling liquid distribution pipes regularly around the porous wall and terminating tangentially on its outside face in a plurality of superposed horizontal injection levels. Feed channels are provided crossing substantially perpendicularly through the distribution pipes, formed between each of them, and connected to cooling liquid feed means. Calibration ducts of determined section are provided, connecting, at each of the injection levels, the vertical feed channels to the horizontal distribution pipes surrounding them, to deliver predetermined headloss to the inside face of the porous wall.

Abstract: The invention relates to an enclosure containing hot gases cooled by transpiration, the enclosure comprising a porous wall and means for applying a cooling fluid to the outside face of said porous wall so as to cause a flow of cooling fluid to pass through the porous wall, by transpiration.

Abstract: The downstream portion of the diverging part of the nozzle of the rocket engine is extended by an ejectable diffuser which, downstream from the zone where it is connected to the diverging part, presents a zone of smaller cross-section that acts during a first stage of flight in the presence of significant outside pressure to recompress the flow of hot gases and to prevent a flow separation from appearing along with the wall of the diverging part. The ejectable diffuser may have a streamlined throat which constitutes the zone of smaller cross-section.

Abstract: In a rocket engine nozzle with a selectively smaller outlet cross-section, the nozzle comprising a converging portion which receives the gases produced in a combustion chamber, a nozzle throat of small cross-section and a diverging part connected to the nozzle throat and terminating at its downstream portion in a gas jet outlet cross-section defining a high cross-section ratio, a releasable annular obstacle is connected to the downstream end of the diverging part so as to define at the outlet of the diverging part a zone of selectively smaller cross-section which ensures stability of the separation of the flow of hot gases relative to the wall of the diverging part during a first phase of flight.

Abstract: In a rocket engine nozzle comprising: a converging portion that receives the gases produced in a combustion chamber; a throat of small section; and a diverging portion connected to the nozzle throat; the diverging portion includes a set of downstream notches running longitudinally from its downstream end and uniformly distributed around the entire periphery of the diverging portion, the total width of all of the notches within any section representing about 1% to 6% of the periphery of the diverging portion. The notches serve to avoid having a jet separation line that is irregular and unstable, and they facilitate matching the diverging portion to ambient conditions that vary in flight.

Abstract: The gas generator comprises an annular main porous piece, at least one calibration lining for defining a flow rate of a first liquid propellant component that is injected through the porous piece towards a combustion chamber that is delimited by one of the faces of the porous piece, and means for radially injecting a flow of a second propellant component into the immediate proximity of the face of the porous piece that delimits the combustion chamber in such a manner as to cause the first and second propellant components to be mixed in the immediate proximity of the face of the porous piece that delimits the combustion chamber.

Abstract: The centrifugal pump with an open-faced impeller comprises at least one open-faced impeller having blades placed inside a casing defining both a delivery pipe and a suction pipe facing the base of the blades situated in the vicinity of a central shaft for driving the impeller. An active axial balancing system for the rotary assembly is integrated in the impeller and comprises a balancing chamber interposed between the rear face of the body of the impeller and an outer rear portion of the casing, the impeller itself acting as the balancing turntable. A shroud-forming intermediate part is prevented from rotating relative to the casing and is interposed between an outer front portion of the casing and the impeller, a cavity is formed between the outer front portion of the casing and the intermediate part to receive a back pressure of predetermined value serving, in operation, to maintain small clearance without contact between the intermediate part that is prevented from rotating and the blades of the impeller.

Abstract: A centrifugal pump with an open-faced impeller for conveying a working liquid, the pump comprising at least one open-faced impeller provided with blades placed inside a casing defining a suction pipe facing the bottoms of the blades in the vicinity of a central shaft that drives the impeller and forming a part of a rotary assembly, and a delivery pipe fitted with a fixed diffuser disposed facing the peripheral ends of the blades. An active axial balancing system for the rotary assembly, which balancing system is integrated in the impeller and comprises a balancing chamber interposed between the rear face of the body of the impeller and an outer rear portion of the casing.