JP2017180938A - Afterburner and aircraft engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently improve maintainability of an afterburner 25 while promoting combustion stability of the afterburner 25.SOLUTION: A flame stabilizer 39 includes six hollow inclined flame holding members 43 disposed in an exhaust duct 29 at even intervals in the circumferential direction. A back surface shape of each of the inclined flame holding members 43 is inclined at an acute angle to the tangential direction of an outer peripheral surface of the exhaust duct 29. Each of the inclined flame holding members 43 is configured to be attachable/detachable to/from the outer peripheral surface of the exhaust duct 29 from the outer side of the exhaust duct 29. A tip of each of the inclined flame holding members 43 is locked while coming into contact with a part of the inclined flame holding member 43 adjacent in the circumferential direction. Each of the inclined flame holding members 43 includes therein a fuel injection pipe 57 for injecting liquid fuel to a combustion region BF in the exhaust duct 29.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an afterburner and the like for reburning combustion gas discharged from a core flow path of an aircraft engine.

  In recent years, various researches and developments have been made on afterburners in response to requests for higher thrust of aircraft engines. Generally, an afterburner includes an exhaust duct provided on the exit side (rear side) of an engine case of an aircraft engine, and a cylindrical liner provided inside the exhaust duct and forming a combustion region in the exhaust duct. ing. The afterburner includes a flame holder that is provided inside the exhaust duct (inside the liner) and holds a flame, and a fuel injector as a fuel injection unit that injects fuel into a combustion region in the exhaust duct. ing. And there are the following three types of flame stabilizers often used for afterburners.

  The first type flame holder has a plurality of annular (annular) annular flame holding members (annular gutta) arranged concentrically in the exhaust duct (in the liner), and each annulus flame holding member. The member can propagate the flame in the circumferential direction. In other words, the first type flame holder has an annular (annular) flame holder capable of propagating the flame. That is, the first type flame holder is an annular type flame holder.

  The second type of flame holder has a plurality of radial flame holding members (radial gutta) arranged radially in the exhaust duct, and each radial flame holding member has a radial direction (liner of the liner). The flame can be propagated in the radial direction. Further, the second type flame holder has an annular (annular) annular flame holding member that connects a plurality of radial flame holding members, and the annular flame holding member propagates the flame in the circumferential direction. It is possible. In other words, the second type flame holder has an annular flame holding portion capable of propagating the flame. That is, the second type flame holder is a composite type flame holder in which a radial type flame holder and an annular type flame holder are combined (see, for example, Patent Document 1 and Patent Document 2).

  The third type flame holder has a plurality of radial flame holding members arranged radially in the exhaust duct, and each radial flame holding member can propagate a flame in the radial direction of the exhaust duct. ing. Further, the third type flame stabilizer has an arc-shaped arch flame retaining member (arch gutta) provided in a part of each radial flame retaining member, and each arch flame retaining member extends in the arc direction. The flame can be propagated. Here, an annular flame holding portion capable of propagating a flame is formed by a plurality of arch flame holding members (a combination of a plurality of arch flame holding members). In other words, the third type flame holder has an annular flame holder capable of propagating the flame in the circumferential direction. That is, the third type flame holder is a split type flame holder obtained by dividing a composite flame holder along the circumferential direction (see Patent Document 3 and the like).

US Patent No. 7600383 U.S. Pat. No. 8,307,658 US Pat. No. 5,396,763

  By the way, as described above, since the first to third types of flame holders have an annular flame holding portion, the flame propagation characteristics of the flame holder are sufficiently ensured, and the combustion stability of the afterburner is ensured. Can be improved. On the other hand, if an annulus flame holding member or arch flame holding member is used as a component of the flame holder, maintenance personnel can access the flame holder only from the inside of the exhaust duct, and the flame holder is easy to maintain. In other words, there is a limit to improving the maintainability of the afterburner. That is, there is a problem that it is difficult to sufficiently improve the maintainability of the afterburner while achieving the combustion stability of the afterburner.

  Therefore, an object of the present invention is to provide an afterburner having a novel configuration that can solve the above-described problems.

  A first aspect of the present invention is an afterburner for recombusting combustion gas discharged from a core flow path of an aircraft engine, an exhaust duct provided on an outlet side (rear side) of an engine case of the aircraft engine; A flame holder that is provided inside the exhaust duct and that holds a flame; and a fuel injection unit (fuel injection means) that injects fuel into a combustion region in the exhaust duct. And a plurality of inclined flame-holding members (inclined gutta) arranged in the exhaust duct at intervals in the circumferential direction and capable of propagating flames, and the rear shape of each inclined flame-holding member (the outlet of the exhaust duct) (Shape viewed from the side) is inclined at an acute angle with respect to the tangential direction of the exhaust duct (tangential direction of the outer peripheral surface of the exhaust duct), and the tip of each inclined flame-holding member is adjacent to the circumferential direction Contact or part of the inclined flame-holding member It is that you are in close proximity.

  According to the first aspect of the present invention, during the operation of the aircraft engine, fuel is injected from the fuel injection portion into the combustion region in the exhaust duct, and the combustion gas containing the fuel is ignited. Then, a combustion gas (including a mixed gas of combustion gas and air) can be recombusted in a combustion region in the exhaust duct while forming a flame on the downstream side (direct downstream side) of the flame holder. . As a result, a large amount of thermal energy can be injected into the combustion gas in the combustion region in the exhaust duct to increase the thrust of the aircraft engine (normal operation of the afterburner).

  As described above, the back surface shape of each inclined flame holding member is inclined at an acute angle with respect to the tangential direction of the exhaust duct, and the tip of each inclined flame holding member is adjacent to the circumferential direction in the inclined direction. It is in contact with or close to a part of the flame holding member. As a result, the flame can be obtained by combining the tip side portions of the plurality of inclined flame holding members without using an annular (annular) annular flame holding member or an arcuate arch flame holding member as a component of the flame holder. Can be formed (a unique action of the afterburner).

  According to a second aspect of the present invention, in an aircraft engine, the afterburner according to the first aspect of the present invention is provided.

  According to the 2nd mode of the present invention, the same operation as the operation by the 1st mode of the present invention is produced.

  According to the present invention, as described above, an annular flame holding portion capable of propagating the flame can be formed by combining the tip side portions of the plurality of inclined flame holding members. Therefore, it is possible to sufficiently ensure the flame propagation property of the flame holder and to improve the combustion stability of the afterburner.

  Further, as described above, it is not necessary to use an annular annulus flame holding member or the like as a component of the flame holder. Therefore, according to the present invention, maintenance personnel can access the flame holder not only from the inside of the exhaust duct but also from the outside of the exhaust duct. Thus, the maintainability of the afterburner can be sufficiently improved.

  That is, according to the present invention, maintainability of the afterburner can be sufficiently improved while achieving combustion stability of the afterburner.

FIG. 1 is a schematic sectional side view of an aircraft engine according to an embodiment of the present invention. In FIG. 1, for convenience of explanation, the circumferential position (circumferential position) of the inclined flame holding member is shifted. FIG. 2 is a schematic enlarged view of the arrow II in FIG. FIG. 3 is an enlarged view taken along line III-III in FIG. 1, and is a longitudinal sectional view of the afterburner according to the embodiment of the present invention. FIG. 4 is an enlarged view of the arrow IV in FIG. FIG. 5 is a perspective view of the flame holder and its surroundings according to the embodiment of the present invention, partially broken away. 6A is an enlarged view of the arrow portion VIA in FIG. 4, FIG. 6B is an enlarged sectional view taken along the line VIB-VIB in FIG. 4, and FIG. 6C is a VIC in FIG. It is an expanded sectional view along the line -VIC. FIG. 7 is a longitudinal sectional view of an afterburner according to another embodiment of the present invention. FIG. 8 is an enlarged view of the arrow VIII in FIG.

  Embodiments of the present invention and other embodiments will be described with reference to the drawings. In the specification and claims of the present application, “provided” means not only being provided directly but also indirectly provided via a separate member, Is synonymous. “Providing” means to provide indirectly through another member in addition to providing directly, and is synonymous with “providing”. “Circumferential direction” refers to a direction along the inner or outer peripheral surface of the exhaust duct. In the drawings, “F” indicates the forward direction (upstream direction), “R” indicates the backward direction (downstream direction), “CD” indicates the circumferential direction, and “TD” indicates the tangential direction.

(Embodiment)
As shown in FIG. 1, the aircraft engine 1 according to the embodiment of the present invention generates thrust (engine thrust) by discharging combustion gas (hot gas) G and air (cold air) A backward. Device. The aircraft engine 1 also includes a cylindrical core case (engine inner cylinder) 3 and an engine case (engine outer cylinder) 5 provided outside the core case 3 and concentrically with the core case 3. . An annular core channel (main channel) 7 is formed inside the core case 3. An annular fan channel (bypass channel) 9 is formed between the inner peripheral surface of the engine case 5 and the outer peripheral surface of the core case 3.

  The engine case 5 is provided with a fan 11 that takes air A into the core flow path 7 and the fan flow path 9 at the front of the engine case 5 (inside the engine case 5). The fan 11 includes an inlet cone 13 that guides the air A in the rear direction at the center of the front side (the front side of the fan 11). Further, the engine case 5 includes a compressor 15 that compresses the air A taken into the core flow path 7 on the rear side of the fan 11. Further, the engine case 5 includes a combustor 17 that combusts the compressed air A on the rear side of the compressor 15.

  The engine case 5 includes a high-pressure turbine 19 that drives the compressor 15 on the rear side of the combustor 17, and the high-pressure turbine 19 is driven by the expansion of the combustion gas G discharged from the combustor 17. ing. The engine case 5 includes a low-pressure turbine 21 that drives the fan 11 on the rear side of the high-pressure turbine 19. The low-pressure turbine 21 is driven by the expansion of the combustion gas G. Furthermore, the core case 3 is provided with a tail cone 23 that guides the combustion gas G in the rearward direction at the rear part thereof (inside the core case 3). The tail cone 23 is located concentrically with the core case 3 and protrudes rearward from the core case 3.

  The engine case 5 recombusts the mixed gas of the combustion gas G discharged from the core flow path 7 and the air (low temperature air) A discharged from the fan flow path 9 on the rear side (rear side of the engine case 5). An afterburner 25 is provided. The afterburner 25 includes an exhaust nozzle 27 that discharges the combustion gas G and air A on the rear side (the rear side of the afterburner 25).

  Then, the specific structure of the afterburner 25 which concerns on embodiment of this invention is demonstrated.

  As shown in FIGS. 1 and 2, the engine case 5 includes an exhaust duct 29 on the outlet side (the outlet side of the engine case 5), and the exhaust duct 29 is located concentrically with the engine case 5. ing. In addition, the exhaust duct 29 includes a cylindrical liner 31 that forms a combustion region BF in the exhaust duct 29 on the inner side (inside the exhaust duct 29) via a plurality of support columns 33. It is located concentrically with the exhaust duct 29. Further, an annular cooling passage 35 for allowing a part of the air A discharged from the fan passage 9 to flow as cooling air CA is provided between the inner peripheral surface of the exhaust duct 29 and the outer peripheral surface of the liner 31. Is formed. The liner 31 has a plurality of film cooling holes 37 through which the cooling air CA can be blown out over the entire area (the entire area of the liner 31). Each film cooling hole 37 penetrates the liner 31.

  The core case 3 includes a mixer (not shown) that mixes the combustion gas G discharged from the core flow path 7 and the air A discharged from the fan flow path 9 at the rear part (the rear part of the core case 3). Also good. The mixer has a known configuration as shown in, for example, JP2013-181473A, JP2012-132630A, and the like.

  The exhaust duct 29 includes a flame holder (frame holder) 39 that holds a flame inside thereof (inside the exhaust duct 29). In other words, the liner 31 includes the flame holder 39 inside thereof (inside the liner 31). Further, the exhaust duct 29 includes an ignition plug (igniter) 41 for igniting (igniting) a mixed gas containing fuel on the downstream side of the flame holder 39. It penetrates. And the specific structure of the flame holder 39 which concerns on embodiment of this invention, and its periphery is as follows.

  As shown in FIG. 2 to FIG. 5 and FIG. 6A, the flame holder 39 has six hollow-shaped elements arranged at equal intervals in the circumferential direction in the exhaust duct 29 (in the liner 31). An inclined flame holding member (inclined gutta) 43 is provided. Each inclined flame-holding member 43 can propagate a flame in its longitudinal direction (longitudinal direction of each inclined flame-holding member 43). Moreover, the cross-sectional shape of each inclined flame-holding member 43 is a V-shape that expands toward the downstream side (rear side) and closes (blocks) the downstream side. Further, the back shape of each inclined flame-holding member 43 (the shape viewed from the outlet side of the exhaust duct 29) is inclined at an acute angle in a straight line with respect to the tangential direction of the outer peripheral surface of the exhaust duct 29. The inclination angle (with respect to the tangential direction of the outer peripheral surface of the exhaust duct 29) θa of the back surface shape of each inclined flame holding member 43 is set to the same angle.

  The number of the inclined flame holding members 43 is not limited to six, and may be three, four, five, seven, or more. The cross-sectional shape of the inclined flame-holding member 43 may be opened on the downstream side instead of closing the downstream side, and may be a U-shape other than the V-shape, for example. The inclination angle θa of the back surface shape of each inclined flame holding member 43 may not be set to the same angle. Instead of the back surface shape of each inclined flame holding member 43 being linearly inclined at an acute angle, the inclined flame holding member 43 may be inclined at an acute angle in a curved shape. The side view shape (the shape seen from the direction along the longitudinal section) of each inclined flame holding member 43 may be a shape curved toward the downstream side or the upstream side. Each inclined flame-holding member 43 may have a curved portion on the proximal end side or the distal end side (the proximal end side or the distal end side of each inclined flame-holding member 43).

  The exhaust duct 29 has a plurality of first insertion holes 45 through which the inclined flame holding member 43 is inserted at equal intervals in the circumferential direction, and each first insertion hole 45 penetrates the exhaust duct 29. doing. The liner 31 has a plurality of second insertion holes 47 through which the inclined flame-holding member 43 is inserted at positions aligned with the respective first insertion holes 45. It penetrates. Each inclined flame-holding member 43 includes a fastening flange 49 on the proximal end side (the proximal end side of each inclined flame-holding member 43). The fastening flange 49 can be fastened to the peripheral edge portion of the corresponding first insertion hole 45 on the outer peripheral surface of the exhaust duct 29 via a plurality of bolts (an example of a fastener) 51. In other words, each inclined flame holding member 43 is configured to be detachable from the outside of the exhaust duct 29 with respect to the outer peripheral surface of the exhaust duct 29. The liner 31 may have a plurality of notches (not shown) for inserting the inclined flame holding member 43 instead of the plurality of second insertion holes 47.

  As shown in FIGS. 3 and 4, each inclined flame-holding member 43 includes, for example, an L-shaped locking hook 53 as a locking portion at the tip (the tip of each inclined flame-holding member 43). Further, the inclined flame holding member 43 adjacent to each inclined flame holding member 43 in the circumferential direction includes, for example, a locked hole 55 as a locked portion to be locked to the locking hook 53. Yes. In other words, the tip of each inclined flame-holding member 43 is locked in a state where it contacts a part of the inclined flame-holding member 43 adjacent in the circumferential direction. In addition, you may adjoin instead of contacting the front-end | tip of each inclination flame holding member 43 to a part of inclination flame holding member 43 adjacent to the circumferential direction.

  As shown in FIGS. 2, 4, and 6 (b) and 6 (c), each inclined flame holding member 43 has liquid fuel in the liner 31 inside (inside each inclined flame holding member 43). A fuel injection pipe 57 is provided as a fuel injection portion for injection. Each fuel injection pipe 57 is connected to a fuel supply source (not shown) for supplying fuel, and a plurality of fuel injection holes 59 capable of injecting fuel are provided in the longitudinal direction (longitudinal direction of each fuel injection pipe 57). ) At intervals. Each inclined flame-holding member 43 has a fuel through hole 61 at a position aligned with each of the plurality of fuel injection holes 59. In other words, each inclined flame holding member 43 has a plurality of fuel through holes 61 respectively communicating with the plurality of fuel injection holes 59. The opening area of each fuel injection hole 59 is larger than the opening area of the fuel injection hole 59. Instead of using the fuel injection pipe 57 as the fuel injection portion, a fuel injector (not shown) provided in the exhaust duct 29 (in the liner 31) independently of the inclined flame holding member 43 may be used. .

  Each inclined flame-holding member 43 has an internal passage 63 inside thereof (inside each inclined flame-holding member 43), and the internal passage 63 is a notch formed on the proximal end side of the inclined flame-holding member 43. It communicates with the cooling flow path 35 via the (opening) 65. Each inclined flame-holding member 43 includes a pipe-like insert 67 inside (inside the internal passage 63). Each insert 67 has a plurality of impingement cooling holes 69 through which cooling air CA can be ejected toward the inner wall surface of the inclined flame-holding member 43 (the wall surface of the internal passage 63). 67 is penetrated. Further, each inclined flame-holding member 43 has an air passage hole 71 communicating with the internal passage 63 on the rear edge side (the rear edge side of each inclined flame-holding member 43). Note that the insert 67 provided inside each inclined flame holding member 43 may be omitted.

  Then, the effect | action and effect of embodiment of this invention are demonstrated.

  When the fan 11 and the compressor 15 are driven by operating an appropriate starter device (not shown), the air A can be taken into the core flow path 7 and the fan flow path 9, and the air A taken into the core flow path 7 can be taken. Can be compressed. And the combustor 17 burns the air A containing fuel, and produces | generates a high pressure combustion gas. Then, the high pressure turbine 19 and the low pressure turbine 21 are driven by the expansion of the combustion gas, and the compressor 15 and the fan 11 can be driven.

  As described above, the aircraft engine 1 is operated by continuously driving the fan 11, the compressor 15, the combustion by the combustor 17, the high-pressure turbine 19, and the low-pressure turbine 21. Can do. As a result, the combustion gas G passing through the core flow path 7 and the air A passing through the fan flow path 9 are exhausted rearward from the exhaust nozzle 27, and the thrust of the aircraft engine 1 (engine thrust) can be generated. The air A exhausted from the exhaust nozzle 27 covers the combustion gas G exhausted from the exhaust nozzle 27 (normal operation of the aircraft engine 1).

  During the operation of the aircraft engine 1, liquid fuel is injected into the combustion region BF in the exhaust duct 29 from the plurality of fuel injection holes 59 of each fuel injection pipe 57 via the fuel through holes 61. Then, the spark plug 41 ignites the mixed gas containing fuel. Then, the mixed gas containing fuel can be recombusted in the combustion region BF in the exhaust duct 29 while forming a flame on the downstream side (direct downstream side) of the flame holder 39. Thereby, a large amount of thermal energy can be injected into the combustion gas G in the combustion region BF in the exhaust duct 29 to increase the thrust of the aircraft engine 1 (normal operation of the afterburner 25).

  On the other hand, during the operation of the aircraft engine 1, a part of the air A discharged from the fan flow path 9 circulates through the cooling flow path 35 as the cooling air CA, whereby the liner 31 can be convectively cooled. Further, the cooling air CA is blown out from the plurality of film cooling holes 37, whereby a film cooling layer (not shown) covering the inner peripheral surface of the liner 31 can be formed, and the film cooling of the liner 31 can be performed. Further, the cooling air CA that has flowed into the inserts 67 from the cooling flow path 35 is ejected from the plurality of impingement cooling holes 69 toward the inner wall surfaces of the inclined flame holding members 43, whereby the inclined flame holding members 43. Impingement cooling (internal cooling) can be performed. The cooling air CA that has contributed to the impingement cooling of each inclined flame holding member 43 is discharged from the plurality of air passage holes 71 to the combustion region BF in the exhaust duct 29.

  As described above, the back surface shape of each inclined flame holding member 43 is inclined at an acute angle with respect to the tangential direction of the outer peripheral surface of the exhaust duct 29, and the tip of each inclined flame holding member 43 is inclined adjacent to the circumferential direction. The flame holding member 43 is locked in contact with a part thereof. As a result, by using the annular (annular) annulus flame holding member or the arcuate arch flame holding member as a component of the flame holder 39, the flames can be combined by combining the tip side portions of the plurality of inclined flame holding members 43. Can be formed (annular action of the afterburner 25).

  Therefore, according to the embodiment of the present invention, the annular flame-holding portion can be formed by combining the tip side portions of the plurality of inclined flame-holding members 43, so that the flame spreadability of the flame holder 39 is sufficiently ensured. The combustion stability of the afterburner 25 can be achieved.

  Further, as described above, there is no need to use an annular annulus flame holding member or the like as a component of the flame holder, and each inclined flame holding member 43 is attached to and detached from the outer peripheral surface of the exhaust duct 29 from the outside of the exhaust duct 29. It is configured to be possible. Therefore, the maintenance staff can access the flame holder 39 not only from the inside of the exhaust duct 29 but also from the outside of the exhaust duct 29, so that the maintenance of the flame holder 39, in other words, the maintenance of the afterburner 25 can be performed. Can be sufficiently improved.

  That is, according to the embodiment of the present invention, the maintainability of the afterburner 25 can be sufficiently improved while the combustion stability of the afterburner 25 is achieved.

  Further, as described above, impingement cooling (internal cooling) can be performed on each inclined flame holding member 43, in other words, the entire flame holder 39. Therefore, according to the embodiment of the present invention, the durability of the flame holder 39, in other words, the durability of the afterburner 25 can be sufficiently improved.

  Further, as described above, the fuel injection pipe 57 is provided inside each inclined flame holding member 43. Therefore, according to the embodiment of the present invention, the fuel distribution in the longitudinal section of the combustion region BF in the exhaust duct 29 can be brought close to a uniform distribution, and the combustion efficiency of the afterburner 25 can be sufficiently increased.

(Other embodiments of the present invention)
As shown in FIGS. 7 and 8, in another embodiment of the present invention, another flame holder 73 is used instead of the flame holder 39 (see FIGS. 3 and 4) as a component of the afterburner 25. ing. Of the configuration of the flame holder 73 according to another embodiment of the present invention, only the differences from the configuration of the flame holder 39 will be described. In addition, about the component corresponding to the component in the flame holder 39 among the some components in the flame holder 73, the same code | symbol is attached | subjected in drawing.

  In addition to the six inclined flame holding members 43, the flame holder 73 includes six hollow auxiliary flame holding members (auxiliary members) arranged in the exhaust duct 29 (in the liner 31) at equal intervals in the circumferential direction. Gutta) 75. In addition, each auxiliary flame holding member 75 is capable of propagating a flame in its longitudinal direction (longitudinal direction of each auxiliary flame holding member 75). The cross-sectional shape of each auxiliary flame holding member 75 is V-shaped, similar to the cross-sectional shape of the inclined flame holding member 43. Further, the back shape of each auxiliary flame holding member 75 is inclined at an acute angle with respect to the tangential direction of the outer peripheral surface of the exhaust duct 29. The inclination angle (inclination angle with respect to the tangential direction of the outer peripheral surface of the exhaust duct 29) θb of the back surface shape of each auxiliary flame holding member 75 is set to the same angle. In addition, the inclination angle θb of the back surface shape of each auxiliary flame holding member 75 may not be set to the same angle.

  The exhaust duct 29 has a plurality of first auxiliary insertion holes 77 through which the auxiliary flame holding member 75 is inserted at equal intervals in the circumferential direction, and each first auxiliary insertion hole 77 has an exhaust duct 29. It penetrates. The liner 31 has a plurality of second auxiliary insertion holes 79 through which the auxiliary flame holding member 75 is inserted at positions aligned with the first auxiliary insertion holes 77. It penetrates the liner 31. Each auxiliary flame holding member 75 includes a fastening flange 81 on the base end side (base end side of each auxiliary flame holding member 75). The fastening flange 81 can be fastened to the peripheral edge portion of the corresponding first auxiliary insertion hole 77 on the outer peripheral surface of the exhaust duct 29 via a plurality of bolts 83. In other words, each auxiliary flame holding member 75 is configured to be detachable from the outer side of the exhaust duct 29 with respect to the outer peripheral surface of the exhaust duct 29, similarly to each inclined flame holding member 43.

  Each auxiliary flame holding member 75 includes, for example, an L-shaped locking hook 85 as a locking portion at its tip (tip of each auxiliary flame holding member 75). In addition, one inclined flame holding member (first inclined flame holding member) 43 of a pair of inclined flame holding members 43 adjacent to each other in the circumferential direction is partly covered by a hook hook 85. For example, a locked hole 87 is provided as the locking portion. In other words, the tip of each auxiliary flame holding member 75 is locked in a state where it contacts a part of the first inclined flame holding member 43. The tip of each auxiliary flame holding member 75 may be close to the first inclined flame holding member 43 instead of contacting a part thereof.

  Each auxiliary flame holding member 75 and its surroundings have the same configuration as each inclined flame holding member 43 and its surroundings. Specifically, each auxiliary flame holding member 75 includes a fuel injection pipe 57 that injects liquid fuel into the liner 31 inside (inside each auxiliary flame holding member 75). Each auxiliary flame holding member 75 has a fuel passage hole (not shown) at a position aligned with each fuel injection hole 59 of the fuel injection pipe 57. Each auxiliary flame holding member 75 has an internal passage (not shown) communicating with the cooling flow path 35 on the inner side (inside each auxiliary flame holding member 75). The auxiliary flame holding member 75 includes an insert 67 on the inner side (in the auxiliary internal passage 75). Each auxiliary flame holding member 75 has a plurality of air passage holes 71 communicating with the internal passage on the rear edge side (the rear edge side of each auxiliary flame holding member 75).

  In other embodiments of the present invention, in addition to the operations and effects of the above-described embodiments of the present invention, the following operations and effects are achieved.

  During operation of the aircraft engine 1, the cooling air CA that has flowed into the inserts 67 from the cooling flow path 35 is ejected from the plurality of impingement cooling holes 69 toward the inner wall surfaces of the auxiliary flame holding members 75. The impingement cooling of each auxiliary flame holding member 75 as well as the inclined flame holding member 43 can be performed. In other words, impingement cooling can be performed on the entire flame holder 39. Therefore, according to another embodiment of the present invention, the durability of the flame holder 39, in other words, the durability of the afterburner 25 can be sufficiently improved.

  A fuel injection pipe 57 is provided not only inside each inclined flame holding member 43 but also inside each auxiliary flame holding member 75. Therefore, according to another embodiment of the present invention, the fuel distribution in the longitudinal section of the combustion region BF in the exhaust duct 29 can be made closer to a uniform distribution, and the combustion efficiency of the afterburner 25 can be more sufficiently increased. .

  In addition, this invention is not restricted to description of the above-mentioned embodiment, It can implement in a various aspect by making an appropriate change. The scope of rights encompassed by the present invention is not limited to the above-described embodiment.

A Air BF Combustion area CA Cooling air G Combustion gas 1 Aircraft engine 3 Core case 5 Engine case 7 Core flow path 9 Fan flow path 25 After burner 27 Exhaust nozzle 29 Exhaust duct 31 Liner 35 Cooling flow path 39 Flame stabilizer 41 Spark plug 43 Inclined flame holding member 45 First insertion hole 47 Second insertion hole 49 Fastening flange 53 Locking hook (locking part)
55 Locked hole (locked part)
57 Fuel injection pipe (fuel injection part)
59 Fuel injection hole 61 Fuel passage hole 63 Internal passage 65 Notch 67 Insert 69 Impingement cooling hole 71 Air passage hole 73 Flame holder 75 Auxiliary flame holding member 77 First auxiliary insertion hole 79 Second auxiliary insertion hole 81 Fastening flange 85 Engagement Stop hook (locking part)
87 Locked hole (locked part)

Claims (8)

An afterburner for reburning combustion gas discharged from a core flow path of an aircraft engine,
An exhaust duct provided on the exit side of the engine case of the aircraft engine;
A flame holder that is provided inside the exhaust duct and holds a flame;
A fuel injection section for injecting fuel into a combustion region in the exhaust duct,
The flame stabilizer has a plurality of inclined flame holding members arranged in the exhaust duct at intervals in the circumferential direction and capable of propagating the flame, and the back surface shape of each inclined flame holding member is the exhaust duct. The afterburner is inclined at an acute angle with respect to the tangential direction, and the tip of each inclined flame-holding member is in contact with or close to a part of the inclined flame-holding member adjacent in the circumferential direction.   The afterburner according to claim 1, wherein each inclined flame-holding member is configured to be detachable from the outer side of the exhaust duct with respect to the outer peripheral surface of the exhaust duct.   The exhaust duct has a plurality of insertion holes through which the inclined flame-holding member is inserted at intervals in the circumferential direction, and the base end side of each inclined flame-holding member corresponds to the outer peripheral surface of the exhaust duct. The afterburner according to claim 2, wherein a fastening flange that can be fastened is provided at a peripheral edge portion of the insertion hole.   A locking portion is provided at the tip of each inclined flame-holding member, and a locked portion to be locked to the locking portion is provided in a part of the inclined flame-holding member adjacent in the circumferential direction. The afterburner according to any one of claims 1 to 3. The fuel injection portion is a fuel injection pipe provided inside each inclined flame holding member and having a fuel injection hole capable of injecting fuel,
The afterburner according to any one of claims 1 to 4, wherein each inclined flame-holding member has a fuel through hole communicating with the fuel injection hole. A cylindrical liner provided inside the exhaust duct and forming a combustion region in the exhaust duct;
Between the inner peripheral surface of the exhaust duct and the outer peripheral surface of the liner, an annular cooling flow passage is formed for circulating a part of the air discharged from the fan flow passage of the aircraft engine as cooling air,
Each inclined flame-holding member has a hollow shape and has an internal passage communicating with the cooling channel on the inner side, and each inclined flame-holding member has an air passage hole communicating with the internal passage. The afterburner according to any one of claims 1 to 5.   The flame holder has a plurality of auxiliary flame holding members arranged in the exhaust duct at intervals in the circumferential direction and capable of propagating flames, and the back surface shape of each auxiliary flame holding member has the inclined holding member. It is inclined at an acute angle with respect to the flame member, and the tip of each auxiliary flame holding member is in contact with a part of one of the inclined flame holding members of the pair of the inclined flame holding members adjacent in the circumferential direction or The afterburner according to any one of claims 1 to 6, which is in close proximity.   An aircraft engine comprising the afterburner according to any one of claims 1 to 7.

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