GB1043524A - Improvements in jet propulsion engines - Google Patents

Abstract

1,043,524. Gas turbine jet engines. BRISTOL SIDDELEY ENGINES Ltd. May 15, 1963 [June 5, 1962], No. 21687/62. Headings F1G and F1L. An aircraft jet propulsion power plant comprises an axial-flow air compressor which delivers air to an annular passage having at least one side outlet which communicates through a stub duct with a swivelling thrust nozzle, a plurality of struts or pillars being spaced around the passage and projecting across it transversely of the direction of airflow therethrough, each strut or pillar carrying a pair of perforated baffles which extend downstream of the strut or pillar and are arranged for relative swinging movement from an open V position with the strut or pillar constituting the apex of the V, to a closed position, there being means for dispersing fuel either into the V-shaped space between each pair of baffles when open, or into the air flowing through the perforations of the baffles into that space, for combustion therein. The engine shown is a gas turbine jet engine of the by-pass type in which air from the low pressure compressor 26 is divided by a partition wall 15 into two streams, the inner stream flowing through annular passage 13 to the high pressure compressor 20, thence through main combustion equipment 60, to high and low pressure turbines 61, 62 finally discharging through jet nozzles. The outer stream of air flows into an annular duct 14 in which is disposed combustion equipment, the duct 14 communicating with two outwardly and downwardly directed stub ducts 28 with which are associated angularly movable thrust nozzles 63 as set forth in Specification 1,013,116. The combustion space within the annular duct 14 is defined by flame tube walls 48, 49, the outer wall 49 being lipped at 59 in the regions of the stub ducts 28 as shown in Fig. 2. A series of struts or vanes 33 extends radially between the walls 23, 32 which together with the intermediate wall 15 define the annular ducts 13, 14, and at the downstream edges of the portions of the struts or vanes 33 which extend across the annular duct 14 are disposed co-axial tubes 38, 39 to which are secured perforated baffles 34, 35. The baffles 34, 35 may be moved to the open position shown in Fig. 4 in which they define a V-shaped combustion stabilizing space into which fuel may be injected through orifices 51 in the tubes 38, 39, or to a closed position in which they are disposed side-by-side and form a downstream continuation of the surfaces of the vane 33. The baffles are formed with perforations 36 and provided with internal deflectors 37. Further tubular members 44, 45 carrying baffles 42, 43 are disposed between the firstmentioned tubular members and baffles, the baffles of adjacent pairs abutting when in the open position. The baffles are adjustable by means of an angularly adjustable ring 65 which surrounds the casing 32, the ring being formed with cam grooves in which are received rollers carried by actuating levers secured to the baffles. The cam grooves may be shaped so that a first set of baffles moves to the open position upon a first angular movement of the ring, and a second set of baffles moves to the open position upon further angular movement of the ring. Fuel may be discharged from the tubular members 38, 39, 44, 45 into the spaces upstream of the baffles, the fuel being carried into the combustion spaces downstream of the baffles by the air flowing through the perforations in the baffles. Again, the fuel may be supplied through separate injection devices disposed upstream of the baffles.