The subject matter disclosed herein generally relates to gas turbine engines and, more particularly, to a method and apparatus for mitigating heat in cooling surfaces of gas turbine engines.
In one example, a combustor of a gas turbine engine may be configured to burn fuel in a combustion area. Such configurations may place substantial heat load on the structure of the combustor (e.g., heat shield panels, combustor shells, etc.). Such heat loads may dictate that special consideration is given to structures, which may be configured as heat shields or panels, and to the cooling of such structures to protect these structures. Excess temperatures at these structures may lead to oxidation, cracking, and high thermal stresses of the heat shields panels.
According to an embodiment, a combustor for use in a gas turbine engine is provided. The combustor includes a heat shield panel having a first surface and a second surface opposite the first surface of the heat shield panel and a combustor shell having an inner surface and an outer surface opposite the inner surface. The inner surface of the combustor shell and the second surface of the heat shield panel being in a facing spaced relationship defining an impingement cavity therebetween. The combustor shell further includes an impingement aperture that has a nonaxisymmetric shape. The impingement aperture extending from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the nonaxisymmetric shape of the impingement aperture extends from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture has only one wall that forms the impingement aperture by extending from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture has two or more walls that forms the impingement aperture by extending from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is crescent-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is star-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is comma-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is oval-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the nonaxisymmetric shape of the impingement aperture is composed of two or more intersecting shapes.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the two or more intersecting shapes are circles.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the two or more intersecting shapes are aligned in an arc.
According to another embodiment, a gas turbine engine is provided. The gas turbine engine including a combustor section and a combustor housed within the combustor section. The combustor including: a heat shield panel having a first surface and a second surface opposite the first surface of the heat shield panel and a combustor shell having an inner surface and an outer surface opposite the inner surface. The inner surface of the combustor shell and the second surface of the heat shield panel being in a facing spaced relationship defining an impingement cavity therebetween. The combustor shell further includes an impingement aperture that has a nonaxisymmetric shape. The impingement aperture extending from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the nonaxisymmetric shape of the impingement aperture extends from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture has only one wall that forms the impingement aperture by extending from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture has two or more walls that form the impingement aperture by extending from the outer surface to the inner surface through the combustor shell.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is crescent-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is star-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is comma-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the impingement aperture is oval-shaped.
In addition to one or more of the features described above, or as an alternative, further embodiments may include that the nonaxisymmetric shape of the impingement aperture is composed of two or more intersecting shapes.
The foregoing features and elements may be combined in any of the various possible combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, that the following description and drawings are intended to be illustrative and explanatory in nature and non-limiting.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
The detailed description explains embodiments of the present disclosure, together with advantages and features, by way of example with reference to the drawings.
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
The exemplary engine 20 generally includes a low speed spool 30 and a high speed spool 32 mounted for rotation about an engine central longitudinal axis A relative to an engine static structure 36 via several bearing systems 38. It should be understood that various bearing systems 38 at various locations may alternatively or additionally be provided, and the location of bearing systems 38 may be varied as appropriate to the application.
The low speed spool 30 generally includes an inner shaft 40 that interconnects a fan 42, a low pressure compressor 44 and a low pressure turbine 46. The inner shaft 40 is connected to the fan 42 through a speed change mechanism, which in exemplary gas turbine engine 20 is illustrated as a geared architecture 48 to drive the fan 42 at a lower speed than the low speed spool 30. The high speed spool 32 includes an outer shaft 50 that interconnects a high pressure compressor 52 and high pressure turbine 54. A combustor 300 is arranged in exemplary gas turbine 20 between the high pressure compressor 52 and the high pressure turbine 54. An engine static structure 36 is arranged generally between the high pressure turbine 54 and the low pressure turbine 46. The engine static structure 36 further supports bearing systems 38 in the turbine section 28. The inner shaft 40 and the outer shaft 50 are concentric and rotate via bearing systems 38 about the engine central longitudinal axis A which is collinear with their longitudinal axes.
The core airflow is compressed by the low pressure compressor 44 then the high pressure compressor 52, mixed and burned with fuel in the combustor 300, then expanded over the high pressure turbine 54 and low pressure turbine 46. The turbines 46, 54 rotationally drive the respective low speed spool 30 and high speed spool 32 in response to the expansion. It will be appreciated that each of the positions of the fan section 22, compressor section 24, combustor section 26, turbine section 28, and fan drive gear system 48 may be varied. For example, gear system 48 may be located aft of combustor section 26 or even aft of turbine section 28, and fan section 22 may be positioned forward or aft of the location of gear system 48.
The engine 20 in one example is a high-bypass geared aircraft engine. In a further example, the engine 20 bypass ratio is greater than about six (6), with an example embodiment being greater than about ten (10), the geared architecture 48 is an epicyclic gear train, such as a planetary gear system or other gear system, with a gear reduction ratio of greater than about 2.3 and the low pressure turbine 46 has a pressure ratio that is greater than about five. In one disclosed embodiment, the engine 20 bypass ratio is greater than about ten (10:1), the fan diameter is significantly larger than that of the low pressure compressor 44, and the low pressure turbine 46 has a pressure ratio that is greater than about five 5:1. Low pressure turbine 46 pressure ratio is pressure measured prior to inlet of low pressure turbine 46 as related to the pressure at the outlet of the low pressure turbine 46 prior to an exhaust nozzle. The geared architecture 48 may be an epicycle gear train, such as a planetary gear system or other gear system, with a gear reduction ratio of greater than about 2.3:1. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present disclosure is applicable to other gas turbine engines including direct drive turbofans.
A significant amount of thrust is provided by the bypass flow B due to the high bypass ratio. The fan section 22 of the engine 20 is designed for a particular flight condition—typically cruise at about 0.8 Mach and about 35,000 feet (10,688 meters). The flight condition of 0.8 Mach and 35,000 ft (10,688 meters), with the engine at its best fuel consumption—also known as “bucket cruise Thrust Specific Fuel Consumption (‘TSFC’)”—is the industry standard parameter of lbm of fuel being burned divided by lbf of thrust the engine produces at that minimum point. “Low fan pressure ratio” is the pressure ratio across the fan blade alone, without a Fan Exit Guide Vane (“FEGV”) system. The low fan pressure ratio as disclosed herein according to one non-limiting embodiment is less than about 1.45. “Low corrected fan tip speed” is the actual fan tip speed in ft/sec divided by an industry standard temperature correction of [(Tram ° R)/(518.7° R)]0.5. The “Low corrected fan tip speed” as disclosed herein according to one non-limiting embodiment is less than about 1150 ft/second (350.5 m/sec).
Referring now to
As illustrated, a combustor 300 defines a combustion chamber 302. The combustion chamber 302 includes a combustion area 370 within the combustion chamber 302. The combustor 300 includes an inlet 306 and an outlet 308 through which air may pass. The air may be supplied to the combustor 300 by a pre-diffuser 110. Air may also enter the combustion chamber 302 through other holes in the combustor 300 including but not limited to quench holes 310, as seen in
Compressor air is supplied from the compressor section 24 into a pre-diffuser 110, which then directs the airflow toward the combustor 300. The combustor 300 and the pre-diffuser 110 are separated by a dump region 113 from which the flow separates into an inner shroud 114 and an outer shroud 116. As air enters the dump region 113, a portion of the air may flow into the combustor inlet 306, a portion may flow into the inner shroud 114, and a portion may flow into the outer shroud 116.
The air from the inner shroud 114 and the outer shroud 116 may then enter the combustion chamber 302 by means of one or more impingement apertures 307 in the combustor shell 600 and one or more effusion apertures 309 in the heat shield panel 400, as shown in
The combustor 300, as shown in
The heat shield panels 400 can be removably mounted to the combustor shell 600 by one or more attachment mechanisms 332. In some embodiments, the attachment mechanism 332 may be integrally formed with a respective heat shield panel 400, although other configurations are possible. In some embodiments, the attachment mechanism 332 may be a threaded mounting stud or other structure that may extend from the respective heat shield panel 400 through the interior surface to a receiving portion or aperture of the combustor shell 600 such that the heat shield panel 400 may be attached to the combustor shell 600 and held in place. The heat shield panels 400 partially enclose a combustion area 370 within the combustion chamber 302 of the combustor 300.
Referring now to
Thus, heat shield panels 400 are utilized to face the hot products of combustion within a combustion chamber 302 and protect the combustor shell 600 of the combustor 300. The heat shield panels 400 may be supplied with cooling air through the impingement apertures 307 and other dilution passages which deliver a high volume of cooling air into a hot flow path. The cooling air may be air from the compressor of the gas turbine engine 20. The cooling air may impinge upon a back side (i.e., second surface 420) of the heat shield panel 400 that faces the combustor shell 600 inside the combustor 300. The cooling air may contain particulates, which may build up on the heat shield panels 400 overtime, thus reducing the cooling ability of the cooling air. Embodiments disclosed herein seek to address particulate adherence to the heat shield panels 400 in order to maintain the cooling ability of the cooling air.
The heat shield panel 400 and the combustor shell 600 are in a facing spaced relationship. The heat shield panel 400 includes a first surface 410 oriented towards the combustion area 370 of the combustion chamber 302 and a second surface 420 opposite the first surface 410 oriented towards the combustor shell 600. The combustor shell 600 has an inner surface 610 and an outer surface 620 opposite the inner surface 610. The inner surface 610 is oriented toward the heat shield panel 400. The outer surface 620 is oriented outward from the combustor 300 proximate the inner shroud 114 and the outer shroud 116.
The combustor shell 600 includes a plurality of impingement apertures 307 configured to allow airflow 590 from the inner shroud 114 and the outer shroud 116 to enter an impingement cavity 390 located between the combustor shell 600 and the heat shield panel 400. Each of the impingement apertures 307 extend from the outer surface 620 to the inner surface 610 through the combustor shell 600. Each of the impingement apertures 307 fluidly connects the impingement cavity 390 to at least one of the inner shroud 114 and the outer shroud 116. Conventionally, these impingement apertures 307 have been circular in shape (see.
The heat shield panel 400 may include one or more effusion apertures 309 configured to allow airflow 590 from the impingement cavity 390 to the combustion area 370 of the combustion chamber 302. Each of the effusion apertures 309 extend from the second surface 420 to the first surface 410 through the heat shield panel 400. Airflow 590 flowing into the impingement cavity 390 impinges on the second surface 420 of the heat shield panel 400 and absorbs heat from the heat shield panel 400.
As seen in
Embodiments disclosed herein seek to reduce the amount of particulate adhering the second surface 420 of the heat shield panel 400 by adjusting the shape of the impingement apertures 307 to disturb vorticities that are conventionally generated by impingement apertures 307 that are circular in shape, which helps better disperse particulate 592.
Referring now to
The impingement aperture 307 of
An impingement aperture 307 that is nonaxisymmetric in shape may have two or more walls 307b that form the impingement aperture 307 by extending from the outer surface 620 to the inner surface 610 through the combustor shell 600 (see
While the impingement apertures 307 of
An impingement aperture 307 that is nonaxisymmetric in shape may be formed by combining various intersecting shapes (e.g.,
Advantageously, manufacturing is eased when the nonaxisymetric shape is formed by intersecting circles. The nonaxisymetric shape may be formed by various manufacturing methods, including but not limited to laser drilling or a water jet.
The impingement aperture 307 of
The impingement aperture 307 of
Impingement apertures 307 that are axisymmetric in shape direct air in an impingement jet in the form of circular vortex rings towards the second surface 420 of the heat shield panel 400 for impingement cooling. These vortices concentrate particulate near the second surface 420 of the heat shield panel 400 and in particular near a stagnation region of the impingement jet where particulate can agglomerate due to small local velocities along surface. This may inadvertently lead to build up of particulate 592 on the second surface 420 of the heat shield panel 400 (see
Technical effects of embodiments of the present disclosure include shaping impingement apertures of combustor lines in an nonaxisymmetric shape to eliminate consistent vortices from the impingement apertures and promote dispersion of particulate.
The term “about” is intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, element components, and/or groups thereof.
While the present disclosure has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this present disclosure, but that the present disclosure will include all embodiments falling within the scope of the claims.
Number | Name | Date | Kind |
---|---|---|---|
7052233 | Fied et al. | May 2006 | B2 |
7926278 | Gerendas et al. | Apr 2011 | B2 |
20050022531 | Burd | Feb 2005 | A1 |
20090308077 | Shelley | Dec 2009 | A1 |
20130156549 | Maldonado | Jun 2013 | A1 |
20130209236 | Xu | Aug 2013 | A1 |
20140238028 | Yamane | Aug 2014 | A1 |
20140290258 | Gerendas et al. | Oct 2014 | A1 |
20170101932 | Stover | Apr 2017 | A1 |
20170343217 | Chen et al. | Nov 2017 | A1 |
20180128177 | Holland et al. | May 2018 | A1 |
20180320898 | Uhm | Nov 2018 | A1 |
20190169998 | Whitfield | Jun 2019 | A1 |
20190277501 | Xu | Sep 2019 | A1 |
Entry |
---|
The Extended European Search Report for Application No. 21154373.1-1009; dated Jun. 16, 2021; 7 pages. |
Communication Pursuant to Article 94(3) EPC dated Dec. 19, 2022; EP Application No. 21154373.1; 5 pages. |
European Search Report for Application No. 21154373.1; Issued Nov. 10, 2023. |
Number | Date | Country | |
---|---|---|---|
20210239320 A1 | Aug 2021 | US |