Патент USA US3025677код для вставки
March 20, 1962 J. M. s‘. KEEN 3,025,666 PROPELLING NOZZLES FOR JET PROPULSION GAS TURBINE ENGINES ' Filed May 6, 1960 z/OH/V M/CHAEZ S70E55’ WEE /v By 9* Attorney ' I nited States Patent O??ce 3,25,5b6 Patented Mar. 20, 1962 1 2 FIGURE 2 is an enlarged sectional view of a portion of the engine of FIGURE 1. 3,025,666 PROPELLENG N OZZLES FOR JET PROPULSION GAS TURBINE ENGINES John Michael Storer Keen, Derby, England, assignor to Rolls-Royce Limited, Derby, England, a company of Great Britain Filed May 6, 1960, Ser. No. 27,336 Claims priority, application Great Britain June 12, 1959 3 Claims. (Cl. 60-35.6) pipe 14 whose downstream end is formed to provide a According to the present invention there is provided a pass passage 18 is supplied, by means not shown, with air Referring to the drawings, 10 indicates a jet propulsion gas turbine engine having a compressor 12, combustion equipment and turbine equipment (not shown) and a jet main, variable area, propelling nozzle 16. The engine and jet pipe are enclosed within a nacelle 38 which extends from adjacent the compressor inlet to 10 adjacent the nozzle outlet and is radially spaced there This invention relates to propelling nozzles for jet pro from whereby there is de?ned an annular by-pass passage pulsion gas-turbine engines. 18 which surrounds the engine and the jet pipe. The by propelling nozzle for ‘a jet propulsion gasaturbine engine compressed by the compressor 12. comprising a main variable area nozzle adapted to be 15 A secondary variable area nozzle 20 is provided at the mounted at, or to form part of, the downstream end of downstream end of the passage 18_ The arrangement the jet pipe of the said engine, an annular air duct sur is such that the air ?owing through the passage 18 is rounding said main nozzle or said jet pipe and provided discharged through the nozzle 20 as an annular stream with a secondary variable area nozzle such that air dis closely surrounding the jet gases discharged through the charged through the secondary nozzle forms an annular 20 nozzle 16. Reheat combustion equipment (not shown) stream closely surrounding the jet gases discharged through the main nozzle, and nozzle adjustment means for varying the effective areas of the main and secondary nozzles, said nozzle adjustment means being such as to permit the effective area of the secondary nozzle to be 25 adjusted independently of that of the main nozzle when is provided in the nozzle 16, the said equipment being adapted to injet fuel into, and to effect combustion of said fuel in, the exhaust gases passing through the nozzle 16, whereby to increase engine performance over a lim ited period. the latter area has a predetermined value. Thus each of said nozzles may be provided with a The outlet end of the nozzle 16 is defined by a series of ?ap members 22 which are arranged in an annular assembly. The ?ap members 22 are supported on pivot series ‘of circumferentially arranged ?aps which may be members 24 which are arranged transversely of the longi moved so that ‘the effective areas of the nozzles may be 30 tudinal axis of the engine. The ?ap members 22 can thus varied in accordance with different engine operating con be swung towards and away from the longitudinal axis ditions. The ?aps of the secondary nozzle preferably ' 0f the engine so as to vary the effective outlet area of the extend downstream of those of the main nozzle. nozzle 16. Preferably the main and secondary nozzles are pro Each ?ap member 22 is provided with a pair of upstand vided with a common adjustment device operation of 35 ing, spaced ‘apart ?anges 26 on that face thereof which which effects simultaneous adjustment of both said nozzles is remote from the gas ?ow passage through the nozzle at all times except when the effective area of the main 16, and carried between the ?anges 26 is a roller 28 which nozzle is at the said predetermined Value. is freely rotatable on a shaft, not shown, supported by the ?anges 26. Thus the adjustment device may comprise a cam mem Each of the rollers 28 engages with one face of a re ber engaging a movable part or parts of the main nozzle, 40 movement of said cam member effecting adjustment of spective cam plate 30, each of the cam plates 30‘ being said part or par-ts, whereby to adjust the effective area of disposed in an inclined position and being carried on an axially movable externally screw threaded spindle 32. the main nozzle, at all times except when a predetermined portion or portions of said cam member engages said The latter form part of an actuating mechanism for turn movable part or parts. 45 ing the i?ap members 22 about their pivots 24 either to Preferably the cam member is movable axially of the wards or away from the longitudinal axis of the engine. main nozzle, the said portion or portions of the cam mem In order to ensure that all of the cam plates 30 move ber extending parallel to the ‘axis of the main nozzle. at the same time and the same distance when they are The invention also comprises a gas turbine jet propul actuated they are all supported within two axially spaced sion engine comprising a main variable area nozzle apart frusto-conical rings 31 which are connected to gether. mounted at the downstream end of the jet pipe of the engine, an annular passage surrounding the jet pipe and Thus relative movements of the cam plates is pre having at its downstream end a secondary variable area vented. nozzle, said annular passages being arranged for the ?ow A strut 34 is provided on each cam plate 30 on that therethrough of air (e.g. ram air or compressed air from 55 face thereof which is remote from the face engaged by a compressor of the engine) which is discharged through the roller 28. The strut 34 carries at its downstream the secondary nozzle as an annular stream closely sur— end a roller 35 which is movable in a track 36. The track 36 is mounted on ‘a further ?ap member 37 which is rounding the jet gases discharged through the main nozzle, and nozzle adjustment means for varying the effective areas of the main and secondary nozzles, said nozzle adjustment means being such as to permit the effective area of the secondary nozzle to be adjusted independently of that of the main nozzle When the latter area has a predetermined value. so pivotally supported on the nacelle 38 enclosing the en— gine. The ?ap members 37 are disposed in an annular array, a flap member 37 being provided for each of the ?ap members 22. Whilst the track 36 shown in the drawings is straight it can if desired be curved so that when the ?aps 22 and In order that the invention can be clearly understood 65 37 are actuated their relative positions are varied. and readily carried into effect one construction of a pro Each ?ap member 37 is spaced downstream of the re pelling nozzle in accordance with the invention will now spective ?ap member v22 whereby a duct 40 is de?ned be particularly described, by way of example only, with therebetween, the duct 40 communicating with the by reference to the accompanying drawings, in which. FIGURE 1 is a view showing a jet propulsion gas 70 pass passage 18. The said actuating mechanism for causing axial move turbine engine having a propelling nozzle in accordance ments of each spindle 32 comprises a screw jack 42 hav~ with the present invention, and 3,025,666 4 3 ranged ?aps pivotally mounted on ‘the jet pipe for varying ing an axially extending screw threaded bore in which the spindle 32 is disposed. the effective area of the same; a secondary variable area nozzle mounted ‘at the downstream end of the annular air duct, said secondary nozzle including a series of It will thus be seen that when the screw jack 42 is ro tated, the spindle 32, which is held against rotation by its circumferentially arranged flaps pivotally connected to connection to the cam plate 30, will be caused to move axially. The cam plate 30' will therefore also move axially whereby the associated ?ap 22 will (according to the direction of movement of the cam plate 30) either be the downstream end of said air duct for varying the ef fective area of the same; means operatively connected respectively to ‘and intermediate of the flaps of said main moved inwardly towards the axis of the nozzle 16 or will and secondary nozzles and movable axially with respect be permitted to move away from this axis under the ac tion of the gas pressure. In order that all of the flap members 22 shall move in unison and in the same direction, all of the screw jacks 42 are rotated by a common mechanism, the said mechanism thereto through a predetermined range, said last-men The gear teeth 45 engage with corresponding gear teeth 46 formed on the exterior of each jack 4-2, and thus when the annular member 44 is rotated the jacks mined range; and an actuator member operatively con nected to said ?rst means and said cam means for axially tioned means including a ?rst means to vary the effective area of said secondary nozzle through the entire pre determined range and a cam means to vary the main nozzle simultaneously with the variance of the secondary comprising a fully annular member 44, only part of 15 nozzle through a portion of the predetermined range while maintaining the effective area of the main nozzle which is shown in the drawings, the member 44 being constant during at least another portion of the predeter provided with gear teeth 45 on its inner periphery. moving the same to actuate the respective ?aps of said main and secondary nozzles. 2. A propelling nozzle ‘for a gas turbine jet propulsion engine comprising: a main nozzle, an annular air duct surrounding said main nozzle, a secondary nozzle carried by said air duct for discharging air through said second ary nozzle in an annular stream closely surrounding jet gases discharged through the main nozzle, said main nozzle and said secondary nozzle each comprising a series 42 are all rotated in a common direction, at the same speed whereby the movement of all the flaps 22 is equal. The annular member 44 is supported in a ball race 46 as shown in FIGURE 2 of the drawings. With the two sets of ?aps 2'2 and 37 in the position shown in FIGURE 2 of the drawings, the outlet area of the nozzle 16 is reduced to its permissible minimum to obtain maximum thrust for take off and a convergent nozzle is de?ned. As can be seen from FIGURE 2 of the drawings, each cam plate 30 is provided with a portion, indicated at 48, which is parallel with the axis of the nozzle 16 whereby of circumferentially arranged pivotally mounted ?aps which are movable to vary effective areas of the respec tive nozzles, a common adjustment device for varying the effective areas of said main nozzle and said secondary nozzle, said device comprising a member movable par allel to the axis of the main nozzle, said member having a plurality of camming surfaces and a plurality of arms, the ?aps of said main nozzle having cam followers for it is possible to adjust the position of the ?aps 37 with out moving the iiaps 22. Such an arrangement enables the area of the duct 40 de?ned by the ?aps 37 to be adjusted ?nely to reduce thrust losses. engaging said oamming surfaces and the flaps of said secondary nozzle having guide tracks slidably engaging When the nozzle above described is in use, air from the said arms, said camming surfaces each having at least by-pass passage 18 ?ows through the duct 49 between the two sets of ?aps to surround the exhaust gasses one portion extending parallel to the axis of the main nozzle and enabling the effective area of said main nozzle to remain constant while the effective area of said second ary nozzle is varied during a predetermined portion of the range of axial movement of said member. and prevent premature expansion thereof, whereby thrust losses are reduced or obviated. It will be appreciated that instead of having a ?at por tion at one end only of each cam plate 30 such a por 3. A propelling nozzle, as claimed in claim 1, includ tion may be provided at both ends. Thus when the said 45 a plurality of circumferentially spaced screw jacks oper reheat combustion equipment is in use and the flaps 22, atively connected to said member, and a common opera‘ - 37 are moved to de?ne a convergent-divergent nozzle, ?ne ing annular gear ring for engaging and operating said adjustment may be made of the position of the flaps 37 without moving the ?aps 22. screw jack simultaneously to impart movement to said If desired a ?at portion may also be formed on each 50 member parallel to the axis of the main nozzle. cam plate 30 at a point substantially midway of its length whereby ?ne adjustment of the position of the flaps 37 may be made when the flaps 22 and 37 are positioned for normal cruise conditions. I claim: References Cited in the ?le of this patent UNITED STATES PATENTS 55 1. A gas turbine jet propulsion engine having a jet pipe for discharging jet gases and ‘an annular air duct surrounding the jet pipe for discharging an annular stream of air closely'surrounding the discharge jet gases, the improvement comprising: a main variable area nozzle 60 mounted at the downstream end of the jet pipe, said main nozzle including a series of circumferentially ar 2,846,844 2,931,169 O’Rourke __________ __ Aug. 12, 1958 Glenn ______________ __ Apr. 5, 1960 2,932,163 Hyde ______________ __ Apr. 12, 1960 OTHER REFERENCES Pearson: “Exhaust Nozzles for Supersonic Aircraft,” Journal of the Royal Areonautical Society, vol. 62; No. 573; September 1958, pp. 658-662; page 662 relied on.