METHOD OF REDUCING BURN-ON TIME
20200230895 ยท 2020-07-23
Assignee
Inventors
Cpc classification
B29C70/545
PERFORMING OPERATIONS; TRANSPORTING
F05D2300/603
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F05D2220/32
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D5/282
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D25/005
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
F01D5/28
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B29C70/302
PERFORMING OPERATIONS; TRANSPORTING
Y02T50/60
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B32B5/26
PERFORMING OPERATIONS; TRANSPORTING
F05D2230/10
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B29C67/0044
PERFORMING OPERATIONS; TRANSPORTING
F05D2230/50
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B32B3/02
PERFORMING OPERATIONS; TRANSPORTING
F05D2300/6034
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
B29C70/30
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A method of reducing a burn-on time of a composite component including a body comprising a plurality of fibres layered between a front face of the body and a rear face of the body within a matrix material, wherein the body comprises an edge face between the front face and the rear face at least partially formed by edges of the layers of fibres. The method comprising shaping an edge portion of the body in order to control a local concentration of vapours from the matrix material at the edge face of the body, the vapours having been produced during heating of the composite component and having passed between the layers of fibre of the body to the edge face.
Claims
1. A method of reducing a burn-on time of a composite component after the composite component has been heated, wherein the composite component comprises a body comprising a plurality of fibres layered between a front face of the body and a rear face of the body within a matrix material, wherein the body comprises an edge face between the front face and the rear face at least partially formed by edges of the layers of fibres, wherein the method comprises: shaping an edge portion of the body in order to control a local concentration of vapours from the matrix material at the edge face of the body, the vapours having been produced during heating of the composite component and having passed between the layers of fibre of the body to the edge face.
2. The method of claim 1, wherein the edge portion is shaped such that positions of the edges of two or more of the layers of fibres are staggered in a direction (D) parallel to the front face of the body, such that at least a portion of the edge face is formed at an non-perpendicular angle relative to the front face.
3. The method of claim 1, wherein the edge portion is shaped by machining the edge face after the body of the composite component has been formed.
4. The method of claim 1, wherein the edge portion is shaped by layering the fibres of the body such that the edges of two or more of the layers of fibres are staggered in a direction (D) parallel to the front face of the body prior to curing the composite component.
5. The method of claim 1, wherein shaping the edge portion of the body comprises bending or folding the body of the composite component out of a plane of the front face to form a bend portion extending along the edge portion.
6. The method of claim 1, wherein the method further comprises providing an edge cap extending at least partially over the front face and the rear face, and around the edge face.
7. The method of claim 1, wherein the method further comprises, installing one or more fasteners passing through the layered fibres of the body, such that the fasteners act to resist separation of the layers of fibres at the edge face.
8. The method of claim 7, wherein the method further comprises providing a strip of resilient material over the front and/or rear faces of the body, the strip of resilient material extending at least partially along the length of the edge face, wherein the fasteners pass though the strip of resilient material.
9. The method of claim 7, wherein the one or more fasteners pass though the body on either side of the bend portion.
10. The method of claim 1, wherein the edge portion is shaped such that the edge face has an undulating profile along the length of the edge face.
11. A composite component for a gas turbine engine, the component comprising a body comprising a plurality of fibres layered between a front face of the body and a rear face of the body within a matrix material, wherein the body comprises an edge face between the front face and the rear face at least partially formed by edges of the layers of fibres, and wherein an edge portion of the body is shaped such that a concentration of vapours from the matrix material at the edge face of the body, that are produced during heating of the composite component and pass between the layers of fibre of the body to the edge face, is reduced.
12. The composite component of claim 11, wherein the positions of the edges of two or more of the layers of fibres are staggered in a direction (D) parallel to the front face of the body, such that at least a portion of the edge face is formed at an non-perpendicular angle relative to the front face.
13. The composite component of claim 11, wherein the component further comprises one or more fasteners passing through the layered fibres adjacent to the edge face.
14. The composite component of claim 11, wherein the component comprises a strip of resilient material provided over the front and/or rear faces of the body, the strip of resilient material extending at least partially along the length of the edge face, wherein the fasteners pass though the strip of resilient material.
15. The composite component of claim 11, wherein the body comprises a bend portion extending along the length of the edge face, wherein the body bends out of a plane of the front and/or rear face at the bend portion.
16. An assembly for an electrical system for a gas turbine engine, the assembly comprising: the composite component according to claim 11; and an electrical component coupled to the body.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0061] Embodiments will now be described by way of example only, with reference to the Figures, in which:
[0062]
[0063]
[0064]
[0065]
[0066]
[0067]
[0068]
[0069]
[0070]
[0071]
[0072]
[0073]
[0074]
[0075]
DETAILED DESCRIPTION OF THE DISCLOSURE
[0076] Aspects and embodiments of the present disclosure will now be discussed with reference to the accompanying figures. Further aspects and embodiments will be apparent to those skilled in the art.
[0077]
[0078] In use, the core airflow A is accelerated and compressed by the low pressure compressor 14 and directed into the high pressure compressor 15 where further compression takes place. The compressed air exhausted from the high pressure compressor 15 is directed into the combustion equipment 16 where it is mixed with fuel and the mixture is combusted. The resultant hot combustion products then expand through, and thereby drive, the high pressure and low pressure turbines 17, 19 before being exhausted through the core exhaust nozzle 20 to provide some propulsive thrust. The high pressure turbine 17 drives the high pressure compressor 15 by a suitable interconnecting shaft 27. The fan 23 generally provides the majority of the propulsive thrust. The epicyclic gearbox 30 is a reduction gearbox.
[0079] An exemplary arrangement for a geared fan gas turbine engine 10 is shown in
[0080] Note that the terms low pressure turbine and low pressure compressor as used herein may be taken to mean the lowest pressure turbine stages and lowest pressure compressor stages (i.e. not including the fan 23) respectively and/or the turbine and compressor stages that are connected together by the interconnecting shaft 26 with the lowest rotational speed in the engine (i.e. not including the gearbox output shaft that drives the fan 23). In some literature, the low pressure turbine and low pressure compressor referred to herein may alternatively be known as the intermediate pressure turbine and intermediate pressure compressor. Where such alternative nomenclature is used, the fan 23 may be referred to as a first, or lowest pressure, compression stage.
[0081] It will be appreciated that the arrangement shown in
[0082] Accordingly, the present disclosure extends to a gas turbine engine having any arrangement of gearbox styles (for example star or planetary), support structures, input and output shaft arrangement, and bearing locations.
[0083] Optionally, the gearbox may drive additional and/or alternative components (e.g. the intermediate pressure compressor and/or a booster compressor).
[0084] Other gas turbine engines to which the present disclosure may be applied may have alternative configurations. For example, such engines may have an alternative number of compressors and/or turbines and/or an alternative number of interconnecting shafts. By way of further example, the gas turbine engine shown in
[0085] The geometry of the gas turbine engine 10, and components thereof, is defined by a conventional axis system, comprising an axial direction (which is aligned with the rotational axis 9), a radial direction (in the bottom-to-top direction in
[0086] One or more components of the gas turbine engine 10 may be manufactured from a composite material, such as a carbon fibre reinforced polymer material. With reference to
[0087] In the arrangement shown in
[0088] The body 110 comprises an edge face 110c formed between the front and rear faces 110a, 110b. As depicted in
[0089] It may be desirable for the composite components and structures of the gas turbine engine 10 to be fire resistant or fire proof. Burn-on time is the time taken from a component to stop burning, e.g. stop producing a flame, after an external heat source, which was sufficient to cause combustion of the component material, has been removed from the component. Burn-on time is one parameter that can be used to quantify how fire resistant a component is. It may be desirable for the burn-on time of composite components of the gas turbine engine to be reduced or minimised. For example, it may be desirable for burn-on time of the components to be less than approximately 2 seconds or less than approximately 1 second.
[0090] When composite components, such as the composite component 100, are exposed to an external heat source, the matrix material 116 can evaporate, sublime and/or thermally decompose to produce a vapour. The vapour may be contained between the layers 114 of the fibres 112 and may pass between the layers 114 to reach an edge of the body, where the vapour may be released, e.g. from the edge face 110c.
[0091] The vapour produced by heating the matrix material 116 may be flammable, and hence, whilst an external heat source is applying a sufficient amount of heat to the component, the vapours being released from the composite component 100 may ignite to produce a flame.
[0092] When the external heat source is removed, the burning vapour may continue to heat the body 110 of the composite component 100 causing more vapour to be produced. Because the vapour passes between the layers of fibres and is released at the edge face, a concentration of the vapour at the edge face, e.g. a local concentration at one or more positions along the edge face, can be sufficient to sustain a flame, increasing the burn-on time. In some arrangements, the concentration of vapours at the edge face may produce an approximately stoichiometric mixture of vapours and oxygen for a combustion reaction of the vapours at the edge.
[0093] With reference to
[0094] With reference to
[0095] With reference to
[0096] The composite component differs in that an edge portion 610 of the body 110 is shaped such that positions of the edges 115 of two or more of the layers 114 of fibres forming the body 110 are staggered in a direction D parallel to the front face 110a of the body. By staggering the layers 114 of the fibres 112 at the edge portion 610 in this way, at least a portion of the edge face 110c is formed at a non-perpendicular angle relative to the front face 110a.
[0097] As depicted, the edge portion 610 may comprise the edge face 110c. Additionally, the edge portion 610 may comprise a portion of the body 110 adjacent, e.g. immediately adjacent, to the edge face 110c that is treated, e.g. shaped, in order to control the concentration of vapours.
[0098] As depicted in
[0099] The edge portion 610 may be shaped by machining the edge portion after the body 110 of the composite component 100 has been formed, e.g. after the body has been cured. In other words, the edge face 110c may be cut using a cutting tool, e.g. a machining tool, such as a milling tool, after the body 110 has been cured.
[0100] Alternatively, the edge portion 610 may be shaped by layering the fibres 112 of the body 110, e.g. prior to curing of the body 110, to form the edge face 110c into the desired shape. For example, the fibres 112 of the body 110 may be layered such that the edges 115 of two or more of the layers 114 of fibres are staggered in the direction D parallel to the front face 110a of the body at the edge face 110c.
[0101] Forming the edge face 110c at a non-perpendicular angle relative to the front face 110a increases the area over which the vapours from the matrix material 116 are released from the body 110. As a result, local concentrations of the vapours at positions along the edge face 110c are reduced. In particular, the local concentrations of the vapours may be reduced to an extent that the concentration of vapour is insufficient to sustain a flame at the edge.
[0102] With reference to
[0103] As shown in
[0104] The presence of the bend portion 700 may act to restrict the passage of vapours between the layers 114 to the edge face 110c, e.g. by creating a tortuous path for the vapour passing towards the edge. The bend portion 700 may therefore reduce the amount of vapour passing between the layers to reach the edge face 110c and may thereby reduce the concentration of vapours at the edge face 110c.
[0105] In the arrangement shown in
[0106] Returning to
[0107] As shown in
[0108] The edge cap 800 may be made from a resilient material. For example, the edge cap may comprise a metallic material, such as titanium. Alternatively, the edge cap 800 may comprise one or more layers of fibres (and associated matrix material) positioned over the layers of fibres forming the body 110. The edge cap 800 may resist lofting, e.g. separation, of layers 114 of the body 110 at the edge face 110c when the composite component is heated, e.g. by virtue of its resilience. As depicted in
[0109] Additionally or alternatively to resisting lofting of the layers 114, the edge cap 800 may be configured to restrict vapours that have passed between the layers 114 from being released from the body 110 at the edge face 110c. For example, the edge cap 800 may be configured to create a seal for vapours at the edge face 110c and/or create a tortuous path for vapours being released from the edge face 110c of the body 110. In some arrangements, the edge cap 800 may comprise fire resistant material, e.g. an intumescent coating or paint, a ceramic material, such as fire cement or a ceramic adhesive.
[0110] In the arrangement shown in
[0111] Returning to
[0112] As depicted in
[0113] As depicted in
[0114] The fasteners 900 may be spaced apart along at least a portion of the length of the edge face 110c, such that the fasteners 900 act to resist separation of the layers along the length or portion of the edge face.
[0115] As depicted in
[0116] In the arrangement shown in
[0117] Furthermore, in the arrangement shown in
[0118] It will be appreciated that when the bend portion 7000 bends through an angle of approximately 180 degrees, such that the body 110 is bent or folded back on itself, the first and second shoulders 902, 904 of the fasteners may both act against the front face 110a or rear face 110b of the body 110. Similarly, in arrangements in which the strips of resilient material 906, 908 are provided, both of the strips may be provided over the front face 110a of the body or over the rear face 110b of the body, e.g. between the front face 110a and the shoulders 902, 904 of the fasteners 900.
[0119] With reference to
[0120] Shaping the edge portion 610 such that the edge face 110c has an undulating profile may be performed in addition to any of the other treatments for controlling local concentration of vapours at the edge face that are described above. For example, the edge portion 610 may be shaped such that the edge face 110c has an undulating profile in addition to forming the edge face at a non-perpendicular angle relative to the front face 110a, providing an edge cap across the edge face 110c, providing one or more fasteners through the layers 114 and/or providing one or more strips of resilient material over the front and/or rear faces 110a, 110b of the component body 110.
[0121] With reference to
[0122] When performing the method 1100, the composite component may be manufactured such that the edge portion of the body is treated in any of the ways described above with reference to
[0123] The third step 1106 may be at least partially performed prior to the second step 1104. For example, during manufacturing of the composite component, e.g. during the first step 1102, the plurality of fibres may be layered such that the positions of the edges of two or more of the layers of fibres are staggered in a direction parallel to the front face of the body.
[0124] Additionally or alternatively, the third step 1106 may be performed at least partially after the second step 1104. For example, the composite component may be machined after the second step 1104, such that the two or more of the layers of fibres forming the edge face are staggered in the direction parallel to the front face of the body. In this way, the edge face, or a portion of the edge face, may be formed at a non-perpendicular angle relative to the front face. In a similar way, the plurality of fibres may be arranged during the first step 1102, and/or the composite component may be machined such that the edge face follows an undulating profile along its length.
[0125] In the third step 1106, the edge portion of the composite component may be treated in any of the ways described above with reference to
[0126] With reference to
[0127] In the arrangement shown in
[0128] As depicted in
[0129] In the arrangement depicted in
[0130] Additionally or alternatively, the edge portion of the composite component provided within the assembly 1200 may be treated by providing an edge cap across the edge, providing one or more fasteners through the layers 114 and/or providing one or more strips of resilient material over the front and/or rear faces 110a, 110b of the component body 110, in order to reduce the local concentration of vapours at the edge face 110c.
[0131] It will be understood that the invention is not limited to the embodiments above-described and various modifications and improvements can be made without departing from the concepts described herein. Except where mutually exclusive, any of the features may be employed separately or in combination with any other features and the disclosure extends to and includes all combinations and sub-combinations of one or more features described herein.