Societe Nationale D'etude Et De Construction De Moteurs D'aviation

Denis R Ansart

Denis J Sandelis

Michel A Desaulty

Serge M Meunier

Rodolphe Martinez

Patrice A Commaret

Patrick Samuel Ciccia

Didier H Hernandez

Christine J Ambrogi

Jacques L Maunand

Jean-Paul D Alary

Eric J Lancelot

Gerard J Bayle Laboure

Etienne S David

Bruno M Quinquenneau

Thierry Andre Chevalier

Bruno James

Jean-Claude Marcel Boudot

Gilles Gerard Lepretre

Richard Emile Staessen

Yves Francois Salan

Bruno M Quinqueneau

The invention relates to the control of air flows for cooling the axial walls of a high-temperature combustion chamber in which the walls are provided with through holes forming multiple perforations, and involves arranging the multiple perforations so that the cooling airflow permeability of the walls in the downstream zone of the chamber decreases in the downstream direction in order to compensate for the effects of the increase in pressure drop due to variation of the gas flow velocity. The invention is particularly applicable to sharply convergent combustion chambers such as twin-head combustion chambers.

Control of cooling flows for high-temperature combustion chambers having

The invention relates to a combustion chamber containing a number of aerohanical injectors mounted in the end of the chamber that connects the upstream end of two annular walls and which are supplied with fuel permanently during operation. The injectors are arranged in two concentric rows around the axis of symmetry and in pairs in longitudinal planes passing through the axis of symmetry. The injectors of the two rows are more or less equidistant from the outlet of the chamber and have axes directed toward the outlet. A carefully considered distribution of the primary holes, dilution holes and the air flow allows the emissions of oxides of nitrogen to be reduced.

Turbomachine combustion chamber with inner and outer injector rows

A system is disclosed for injecting air and fuel into a combustion chamber of a turbojet engine in which the system includes a fuel injector having an axis A, a first radial swirler located rearwardly of the fuel injector having a plurality of first air passages to direct air into the fuel emanating from the fuel injector in a first plane generally perpendicular to the axis A, a housing located rearwardly of the first radial swirler and forming a pre-mixing chamber bounded by a converging-diverging wall forming a venturi with a throat, the housing having a plurality of second air passages forming a second radial swirler to direct air into the pre-mixing chamber forwardly of the venturi throat in a second plane generally perpendicular to the axis A. The housing also has a plurality of third air passages forming an axial swirler, the second passages and the third passages alternating in a circumferential direction around the housing. A bowl member has a flanged portion connected to the housing and is located rearwardly of the housing such that fuel and air emanating from the premixing chamber and air emanating from the axial swirler pass into the bowl member and are subsequently mixed and passed into the combustion chamber, to which the bowl member is attached.

Fuel injection system with improved air/fuel homogenization

A gas turbine engine combustion chamber bounded by inner and outer annular walls extending around a longitudinal axis of the engine and connected by an end wall, through which extend a plurality of fuel injectors, each with an intake air swirler. The outer annular wall has a plurality of first orifices arranged in a common plane and spaced apart in a circumferential direction such that each first orifice is circumferentially associated with a fuel injector and is located on one side of a radius line extending from the longitudinal axis and passing through the axis of the associated fuel injector, and a plurality of second orifices in the inner annular wall arranged in a common plane and spaced apart in a circumferential direction such that each second orifice is circumferentially associated with a fuel injector and is located on an opposite side of the radius line from the first orifice associated with the same fuel injector.

Gas turbine engine combustion chamber for optimizing the mixture of

A combustion chamber, particularly for a turbomachine, has at least one generally axially extending wall provided with a plurality of through holes defining a multi-hole cooling system for the wall. The wall also has a plurality of dilution holes which affect locally the flow of burnt gases in the chamber, and the cooling through holes are oriented according to the local flow of burnt gases in the chamber. In particular the wall is subdivided into first zones, downstream of the dilution holes, in which the through holes are oriented substantially in countercurrent to the overall flow direction of the burnt gases in the chamber, second zones and third zones which are disposed on opposite sides of the first zones and in which the orientation of the through holes is inclined both axially and circumferentially, and a fourth zone covering the remainder of the wall and in which the through holes are inclined axially in the overall flow direction of the burnt gases.

Combustion chamber having a multi-hole cooling system with variably

A wall is disclosed for a gas turbine engine combustion chamber having a generally annular configuration around a central axis wherein the wall has an inner surface bounding at least a portion of the combustion chamber and a plurality of rows of cooling openings, each cooling opening having an elongated, generally rectangular configuration with a length l and a width e such that l is greater than e, the cooling openings in each row being equidistantly spaced apart a distance d in which d is not greater than the length l. The cooling openings of a given row are circumferentially displaced from cooling openings of an adjacent row and, since the distance d is not greater than the length l of the cooling openings, the opening areas overlap in adjacent rows to provide an even distribution of the cooling film within the combustion chamber.

Annular combustion chamber with a perforated wall

A fuel injection assembly for a combustion chamber of a gas turbine engine is disclosed in which a plurality of premixing chambers are in communication with the combustion chamber and adjacent pairs of the premixing chambers are connected to a single prevapoization chamber by prevaporization conduits. Fuel is injected into the prevaporization chamber via a fuel injector and is mixed with oxidizer passing into the prevaporization chamber such that the fuel/oxidizer mixture has a richness exceeding the stoichiometric ratio. The fuel/oxidizer mixture passes into the prevaporization conduits through a diaphragm opening and, upon entering the premixing chamber, is mixed with additional oxidizer such that the fuel/oxidizer mixture in each premixing chamber has a richness less than the stoichiometric ratio. The premixing chambers are bounded by generally tubular walls, a portion of each adjacent tubular wall forming a protective hood between the fuel injector and the combustion chamber so as to prevent self-ignition of the fuel/oxidizer mixture in the prevaporization chamber. Oxidizer entering the premixing chambers passes through one or more oxidizer swirlers to assure a complete mixing of the fuel and oxidizer prior to its passing into the combustion chamber.

Fuel injection assembly for a gas turbine engine

An improved dual-head combustion chamber is disclosed having a generally annular configuration extending about a central axis with a low power head, operating during low power engine conditions and a radially displaced high power head operative under high power engine operating conditions. The low power head has N number of fuel/air injector assemblies arranged in an annular array and spaced apart in a circumferential direction about the central axis. The fuel/air injector assemblies of the low power head have an air permeability of P1. The high power head also is arranged in a generally annular array with N number of first fuel/air injector assemblies and N number of second fuel/air injector assemblies with each of the second fuel/air injector assemblies aligned with a fuel/air injector assembly of the low power head along a radius line extending from the central axis. The second fuel/air injector assemblies have an air permeability of P2 such that P2 is greater than P1 and supply a fuel/air mixture to the combustion chamber during high power operation. The first fuel/air injector assemblies located in the high power head are located circumferentially spaced between adjacent second fuel/air injector assemblies. The first fuel/air injector assemblies have an air permeability of P1 and supply fuel/air mixture to the combustion chamber during low power operation.

Dual head combustion chamber

A method of supplying fuel to a combustion chamber of a turbojet engine having a low power head with a plurality of low power fuel injectors and a high power head having a plurality of high power fuel injectors is disclosed in which fuel is supplied to the plurality of low power fuel injectors during low power operation of the engine, fuel is supplied to a first fuel circuit in the plurality of high power fuel injectors during high power operation of the turbojet engine and fuel is also supplied to a second fuel circuit in the plurality of high power fuel injectors during low power operation of the turbojet engine, the second fuel circuit being separate from the first fuel circuit. This method of supplying fuel to the dual head combustion chamber optimizes operation of the combustion chamber in all modes of engine operation.

Method of supplying fuel to a dual head combustion chamber

A wall structure for a wall bounding a combustion chamber of a gas turbine engine is disclosed having a first wall with an inner surface facing towards the interior of the combustion chamber and an outer surface facing away from the interior of the combustion chamber such that the inner surface forms a boundary of the combustion chamber and the outer surface has a surface roughness to prevent the formation of a fluid flow cooling layer which would cool the outer surface. The invention also has a second wall spaced from the outer surface of the first wall in a direction away from the interior of the combustion chamber so as to define a cooling fluid circulatory space between the first and second walls. A plurality of first perforations extend through the first wall in communication with the cooling fluid circulatory space to enable passage of cooling fluid from the space through the first perforations to form a cooling fluid film on the inner surface of the first wall.

Double wall construction for a gas turbine combustion chamber

A pre-mixing injection system to feed a fuel/air mixture to a combustion zone in a turbojet engine combustion chamber is disclosed having a pre-mixing tube defining a convergent pre-mixing zone and a diverging intermediate zone between the fuel and air injection devices, and the combustion zone of the combustion chamber. The convergent pre-mixing zone has an inlet adjacent to the fuel injector and air swirlers to accept the fuel/air mixture into the pre-mixing tube. The pre-mixing zone converges in a direction from the inlet to an outlet which is in communication with the inlet of the divergent intermediate zone. The divergent intermediate zone has an outlet which is, in turn, in communication with the combustion zone of the turbojet engine combustion chamber. The divergent intermediate zone is defined by an inner wall and an outer wall spaced from the inner wall so as to define a generally frusto-conical chamber between them. The outer wall has a plurality of cooling holes to enable cooling air to pass through the outer wall into cooling contact with the inner wall. The frusto-conical chamber has a downstream evacuation passage to allow cooling air to pass from the frusto-conical chamber.

Pre-mixing injection system for a turbojet engine

An arrangement for removably fixing a thermal protection tile on the inside of a combustion chamber wall is described. In one form the tile is provided with a fixing stud which is arranged to pass through a hole in the wall, and a split washer is inserted under the head of the stud to lock the assembly to the wall. In another form the tile is provided with a fixing stud having a head which is arranged to be inserted in a socket welded to the inner surface of the wall and which is locked in place by a stop inserted through a hole in the wall to abut the edge of the head and prevent its removal from the socket.

Fixing arrangement for a thermal protection tile in a combustion chamber

A cladded combustion chamber construction is disclosed in which the cladd tiles can be assembled and replaced without the necessity of disassembling the structural wall of the combustion chamber. The combustion chamber has a generally cylindrical wall with external and internal surfaces bounding the combustion chamber and has a plurality of cladding tiles located on one of the external and internal surfaces of the wall. To attach the cladding tiles to the combustion chamber structure, a plurality of channel shaped attaching devices are utilized extending in a generally circumferential direction around the wall of the combustion chamber and having a portion extending generally parallel to the wall, but spaced from the wall. The portion extending parallel to the wall of the combustion chamber has a circumferentially extending cut out portion whose circumferential length is slightly greater than the width of a cladding tile. The channel shaped attaching devices are spaced axially along the wall of the combustion chamber and are spaced apart a distance slightly greater than a length of a cladding tile. In order to attach the cladding tile to the combustion chamber wall, it is merely necessary to place one end of the tile in one of the channel members and to pass the other end of the tile through the circumferential cut out of the other attaching channel.

Cladded combustion chamber construction

A fuel injection system for a gas turbine engine combustion chamber is disclosed having a sleeve defining a passageway extending along a longitudinal axis of a combustion zone, a first fuel injector orifice to inject fuel into the passageway, and second fuel injector holes arranged in a plurality of substantially linear arrays extending radially from the sleeve and angularly equidistantly spaced from each other, the second fuel injection holes located in a plane extending substantially perpendicular to the longitudinal axis of the combustion chamber such that the plane is located axially between an upstream end wall of the combustion chamber and the downstream end of the sleeve. The system also includes a flameholder having a plurality of flameholder arms extend axially from second fuel injection arms such that the downstream ends of the flameholder arms extend to at least the downstream end of the sleeve and extend generally radially from the sleeve such that the flameholder arms are circumferentially located between the angularly spaced apart linear arrays of fuel injection holes.

Growing community of inventors

Bois-le-Roi, France

Denis R Ansart