Snecma

Snecma Moteurs

Dominique Valentian

François Danguy

Damien Feger

Olivier Bernard Duchemin

Noël Marchal

Olivier Lagnel

Olivier Duchemin

A cryogenic liquid storage system for a spacecraft comprising at least one liquid tank with an outer casing and an evacuated space arranged between the tank and the outer casing. The system further comprises a propellant management device made of material that is a good conductor of heat and that is cooled by a cryorefrigerator to localize the liquid inside the tank when in microgravity, a filler pipe situated in the portion of the tank that is at the bottom when the tank is on the ground, and that is surrounded by an evacuated insulating double wall and a purge pipe connecting the tank to the outer casing and presenting an internal length that is not less than half the diameter of the tank.

Cryogenic liquid storage system for a spacecraft

The electrolytic ignitor comprises an injector constituting a first electrode, a second electrode that is electrically insulated from the injector and that extends downstream beyond the injector, and a distribution channel to deliver a first mono-propellant to a first mono-propellant injector device constituted by at least one injection hole opening out in the vicinity of the second electrode, and an electrical power supply circuit adapted to raise the second electrode to a potential lying in the range 50 V to 1000 V relative to the potential of the first electrode. The electrical power dissipated by ionic conduction in the free jet of the first mono-propellant is suitable for giving rise to spontaneous decomposition of the first mono-propellant and for producing combustion gas that ensures ignition of jets of a second mono-propellant coming from a main injector situated in the vicinity of the second electrode.

Electrolytic igniter for rocket engines using monopropellants

The electrolytic ignitor comprises an injector constituting a first electrode and including a fuel injector device, an oxidizer injector device, and an electrolyte injector device. A second electrode electrically insulated from the injector extends downstream beyond the injector. An electrolyte distribution channel for delivering electrolyte in the form of free jets through the electrolyte injector device comprises at least one injection hole in the vicinity of the fuel injector device and the oxidizer injector device. An electrical power supply circuit is adapted to raise the second electrode to a potential in the range 50 V to 1000 V relative to the potential of the first electrode. The electrolyte injected through the injection hole is capable of causing ignition of a gaseous mixture in a combustion chamber of an ignitor torch suitable for incorporating in a main injector of a rocket engine.

Electrolytic igniter for rocket engines using liquid propellants

An emitter for an ion thruster. The emitter is a field-effect emitter for a field emission electric propulsion or colloid thruster. The field-effect emitter has a first and second portions defining an internal reservoir for supplying a liquid metal or a conducting ionic liquid and has a slit connecting the internal reservoir to an exit orifice.

Emitter for ionic thruster

In a closed electron drift thruster, a magnetic circuit for creating a magnetic field in a main annular channel comprises at least one axial magnetic core surrounded by a first coil and an inner upstream pole piece forming a body of revolution, together with a plurality of outer magnetic cores surrounded by outer coils. The magnetic circuit further comprises an essentially radial outer first pole piece defining a concave inner peripheral surface and an essentially radial second pole piece defining a convex outer peripheral surface. The concave inner peripheral surface and the convex outer peripheral surface present respective adjusted profiles that are distinct from circular cylindrical surfaces so as to form between them a gap of varying width presenting zones of maximum value in register with the outer coils and zones of minimum value in between the outer coils so as to create a uniform radial magnetic field.

Closed electron drift thruster

The compressor-evaporator system for liquefied gas contained in a tank comprises, in addition to a deice for evaporation by heat exchange with a liquid and devices for conditioning and transferring gas to a pipeline, a motor-driven turbopump comprising a rotary assembly of high bending stiffness on a common shaft line, with at least one high pressure pump, a turbine, and a central electrical machine capable of being used in motor mode or in generator mode. The rotary assembly of the motor-driven turbopump is adapted to present a high speed of rotation, greater than 12,000 rpm, while remaining outside ranges for exciting critical speeds in rotation. All of the internal portions of the motor-driven turbopump are immersed in a cryogenic fluid that is the same as the liquefied gas contained in the tank. The internal cavities of the motor-driven turbopump that are under different thermodynamic conditions are separated by contactless dynamic seals. Electronic power circuits connected to an electricity network control the central electrical machine in motor mode or generator mode.

Compression-evaporation system for liquefied gas

The cryogenic rotary coupling comprises segments of a cryogenic line that are capable of turning relative to each other about a pivot axis of the rotary coupling. Radial retaining elements and axial retaining elements define the pivot axis of the rotary coupling. One of the segments comprises a vacuum-insulated double-walled female portion and the other segment comprises a vacuum-insulated double-walled male portion engaged at least in part in the female portion. A first sealing gasket is interposed between a free end of the male portion engaged in the female portion and one of the retaining means. A second sealing gasket is interposed between a free end of the female portion surrounding the male portion and the other one of the retaining elements. A heater device is disposed in the vicinity of the second gasket.

Cryogenic rotary coupling, and use thereof in particular in articulated fluid feed lines, and in cryogenic propellant rocket engines

The cryogenic propulsion module comprises a main cryogenic thruster ( ), two attitude-controlling secondary thrusters ( ), tanks ( ) for feeding cryogenic propellants, a device for intermittently pressurizing the tanks ( ), and a device for initiating firing of the main cryogenic thruster ( ) in intermittent manner while the tanks ( ) are intermittently pressurized. The device for intermittently pressurizing a tank ( ) comprises a heat exchange circuit associated with a heat accumulator ( ) and a device ( ) for putting a predetermined quantity of a propellant into circulation in the heat exchanger circuit. The module also comprises a device for heating the heat accumulator ( ) in the periods between two consecutive firings.

Growing community of inventors

Rosny sur Seine, France

Dominique Valentian