This application relates to heat transfer members associated with cooling passages in gas turbine engine components wherein a fillet connecting the member to a wall is asymmetric.
Gas turbine engines are known, and typically have a fan delivering air into a bypass duct as propulsion air. Air is also delivered into a compressor, and compressed air is delivered into a combustor where it is mixed with fuel and ignited. Products of this combustion pass downstream over turbine rotors, driving them to rotate.
As is known, components associated with the turbine section see products of combustion. As an example, there are rotating turbine blades, intermediate static stator vanes, and blade outer air seals which provide a seal outwardly of the rotating turbine blades. These components see very high temperatures, and thus are typically provided with cooling air.
Cooling air cavities within such turbine components are complex. Heat transfer enhancement members are included to increase the cooling effect provided by the cooling air. As an example, pedestals are provided which extend between spaced walls of a cooling channel. So called “race tracks,” are oval shaped pedestals. Also, so called “pin fins” extend from one wall toward another.
All of these heat transfer members have a fillet at a location where they connect into the wall. The fillets tend to be symmetric about a center line.
In a featured embodiment, a gas turbine engine component includes a body having an internal cooling passage with opposed walls and an array of heat transfer members attached to at least one of the opposed walls each with at least one fillet. There is an airflow direction through the cooling cavity such that the heat transfer members have a leading edge and a trailing edge. The at least one fillets have a leading edge and a trailing edge. A fillet portion leading edge is asymmetric relative to a fillet portion trailing edge to control an air flow direction towards downstream ones of the heat transfer members in the array.
In another embodiment according to the previous embodiment, the fillet portion leading edge is relatively large compared to the fillet portion trailing edge.
In another embodiment according to any of the previous embodiments, the fillet portion leading edge is small compared to the fillet portion trailing edge.
In another embodiment according to any of the previous embodiments, the heat transfer components are attached to each of the spaced walls and there are two of the at least one fillets, and each of the two fillets having a leading edge portion which is asymmetric from a trailing edge portion.
In another embodiment according to any of the previous embodiments, the heat transfer members have a central portion intermediate the at least two fillets. The central portion has a similar cross-sectional shape to a cross-sectional shape of each of the two fillet portions.
In another embodiment according to any of the previous embodiments, the heat transfer members have a central portion intermediate the two fillets, and the central portion and the fillet portions have distinct cross-sectional shapes.
In another embodiment according to any of the previous embodiments, the two fillets are asymmetric relative to each other.
In another embodiment according to any of the previous embodiments, the heat transfer components have a leading edge of one of the at least two fillets attached to one of the at least two walls being small and a leading edge fillet portion of the other of the fillets attached to a second of the walls being relatively large. A trailing edge portion of the fillet is attached to the first of the walls being relatively large and a trailing edge portion of the second of the fillets is attached to the second of the walls being relatively small such that cooling air is directed to the second of the walls.
In another embodiment according to any of the previous embodiments, the component is a rotating turbine blade.
In another embodiment according to any of the previous embodiments, the component is a static stator vane.
In another embodiment according to any of the previous embodiments, the component is a blade outer air seal.
In another embodiment according to any of the previous embodiments, the heat transfer member is a pedestal having a cylindrical central section.
In another embodiment according to any of the previous embodiments, the heat transfer component has a central portion which is generally oval.
In another embodiment according to any of the previous embodiments, the heat transfer component is a pin fin attached to only one of the at least two wall through only one fillet.
In another featured embodiment, a gas turbine engine component includes a body having an internal cooling passage with opposed walls and a heat transfer member attached to at least one of the opposed walls at a fillet. There is an airflow direction through the cooling cavity such that the heat transfer member has a leading edge and a trailing edge. The at least one fillet has a leading edge and a trailing edge. A fillet portion leading edge is asymmetric relative to a fillet portion trailing edge. The heat transfer components are attached to each of the spaced walls and there are two of the at least one fillets. Each of the two fillets have a leading edge portion which is asymmetric from a trailing edge portion. The two fillets are asymmetric relative to each other. The heat transfer components have a leading edge of one of the at least two fillets attached to one of the at least two walls being small and a leading edge fillet portion of the other of the fillets attached to a second of the walls being relatively large. A trailing edge portion of the fillet is attached to the first of the walls being relatively large and a trailing edge portion of the second of the fillets is attached to the second of the walls being relatively small such that cooling air is directed to the second of the walls.
In another embodiment according to any of the previous embodiments, the heat transfer members have a central portion intermediate the at least two fillets. The central portion has a similar cross-sectional shape to a cross-sectional shape of each of the two fillet portions.
In another embodiment according to any of the previous embodiments, the heat transfer members have a central portion intermediate the two fillets. The control portion and the fillet portions have distinct cross-sectional shapes.
In another featured embodiment, a gas turbine engine includes a compressor section delivering compressed air into a combustor. The combustor is configured to mix fuel with compressed air and ignite the mixture. Products of the combustion are configured to pass over a turbine section. The turbine section includes a plurality of components with at least one of the components being provided. A gas turbine engine component includes a body having an internal cooling passage with opposed walls and an array of heat transfer members attached to at least one of the opposed walls each with at least one fillet. There is an airflow direction through the cooling cavity such that the heat transfer members have a leading edge and a trailing edge. The at least one fillets having a leading edge and a trailing edge. A fillet portion leading edge is asymmetric relative to a fillet portion trailing edge to control an air flow direction towards downstream ones of the heat transfer members in the array.
In another embodiment according to any of the previous embodiments, the heat transfer components are attached to each of the spaced walls and there are two of the at least one fillets. Each of the two fillets have a leading edge portion which is asymmetric from a trailing edge portion. The two fillets are asymmetric relative to each other.
In another embodiment according to any of the previous embodiments, the heat transfer components have a leading edge of one of the at least two fillets attached to one of the at least two walls being small and a leading edge fillet portion of the other of the fillets attached to a second of the walls being relatively large. A trailing edge portion of the fillet is attached to the first of the walls being relatively large and a trailing edge portion of the second of the fillets is attached to the second of the walls being relatively small such that cooling air is directed to the second of the walls.
The present disclosure may include any one or more of the individual features disclosed above and/or below alone or in any combination thereof.
These and other features of the present invention can be best understood from the following specification and drawings, the following of which is a brief description.
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 first (or low) pressure compressor 44 and a first (or low) pressure turbine 46. The inner shaft 40 is connected to the fan 42 through a speed change mechanism, which in the 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 inner shaft 40 may interconnect the low pressure compressor 44 and low pressure turbine 46 such that the low pressure compressor 44 and low pressure turbine 46 are rotatable at a common speed and in a common direction. In other embodiments, the low pressure turbine 46 drives both the fan 42 and low pressure compressor 44 through the geared architecture 48 such that the fan 42 and low pressure compressor 44 are rotatable at a common speed. Although this application discloses geared architecture 48, its teaching may benefit direct drive engines having no geared architecture. The high speed spool 32 includes an outer shaft 50 that interconnects a second (or high) pressure compressor 52 and a second (or high) pressure turbine 54. A combustor 56 is arranged in the exemplary gas turbine 20 between the high pressure compressor 52 and the high pressure turbine 54. A mid-turbine frame 57 of the engine static structure 36 may be arranged generally between the high pressure turbine 54 and the low pressure turbine 46. The mid-turbine frame 57 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.
Airflow in the core flow path C is compressed by the low pressure compressor 44 then the high pressure compressor 52, mixed and burned with fuel in the combustor 56, then expanded through the high pressure turbine 54 and low pressure turbine 46. The mid-turbine frame 57 includes airfoils 59 which are in the core flow path C. 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 the low pressure compressor, or aft of the combustor section 26 or even aft of turbine section 28, and fan 42 may be positioned forward or aft of the location of gear system 48.
The low pressure compressor 44, high pressure compressor 52, high pressure turbine 54 and low pressure turbine 46 each include one or more stages having a row of rotatable airfoils. Each stage may include a row of vanes adjacent the rotatable airfoils. The rotatable airfoils are schematically indicated at 47, and the vanes are schematically indicated at 49.
The engine 20 may be a high-bypass geared aircraft engine. The bypass ratio can be greater than or equal to 10.0 and less than or equal to about 18.0, or more narrowly can be less than or equal to 16.0. The geared architecture 48 may be an epicyclic gear train, such as a planetary gear system or a star gear system. The epicyclic gear train may include a sun gear, a ring gear, a plurality of intermediate gears meshing with the sun gear and ring gear, and a carrier that supports the intermediate gears. The sun gear may provide an input to the gear train. The ring gear (e.g., star gear system) or carrier (e.g., planetary gear system) may provide an output of the gear train to drive the fan 42. A gear reduction ratio may be greater than or equal to 2.3, or more narrowly greater than or equal to 3.0, and in some embodiments the gear reduction ratio is greater than or equal to 3.4. The gear reduction ratio may be less than or equal to 4.0. The fan diameter is significantly larger than that of the low pressure compressor 44. The low pressure turbine 46 can have a pressure ratio that is greater than or equal to 8.0 and in some embodiments is greater than or equal to 10.0. The low pressure turbine pressure ratio can be less than or equal to 13.0, or more narrowly less than or equal to 12.0. Low pressure turbine 46 pressure ratio is pressure measured prior to an 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. It should be understood, however, that the above parameters are only exemplary of one embodiment of a geared architecture engine and that the present invention is applicable to other gas turbine engines including direct drive turbofans. All of these parameters are measured at the cruise condition described below.
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 (10,668 meters). The flight condition of 0.8 Mach and 35,000 ft (10,668 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. The engine parameters described above, and those in the next paragraph are measured at this condition unless otherwise specified.
“Fan pressure ratio” is the pressure ratio across the fan blade 43 alone, without a Fan Exit Guide Vane (“FEGV”) system. A distance is established in a radial direction between the inner and outer diameters of the bypass duct 13 at an axial position corresponding to a leading edge of the splitter 29 relative to the engine central longitudinal axis A. The fan pressure ratio is a spanwise average of the pressure ratios measured across the fan blade 43 alone over radial positions corresponding to the distance. The fan pressure ratio can be less than or equal to 1.45, or more narrowly greater than or equal to 1.25, such as between 1.30 and 1.40. “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 corrected fan tip speed can be less than or equal to 1150.0 ft/second (350.5 meters/second), and can be greater than or equal to 1000.0 ft/second (304.8 meters/second).
As mentioned above, components in the turbine section see very high temperatures and are typically provided with cooling air. An example rotating turbine blade 100 is illustrated in
A so called race track 126, which is essentially an oval shaped pedestal, extends between ends 128 and 130 attached to walls 110 and 108, respectively. Here again, there will typically be fillets at the ends 128 and 130. A pin fin 132 extends from wall 110 towards wall 108 but does not reach wall 108. An end 134 is provided with a fillet.
The cooling paths 145 and 143 will include heat transfer members such as described with regard to
As shown in
Returning to
Applicant has recognized that by modifying the fillets to be asymmetric one can control the direction of cooling airflow across the pedestals. The fillets can also be maximized to increase a cold side surface area to increase heat transfer. The same would be true of race tracks or pin fins such as shown in
A first embodiment 200 according to this disclosure is illustrated in
As shown, this arrangement will direct cooling air associated with the fillets in a direction toward the walls 108 and 110.
As shown in
As shown in
As shown in
As shown in
As shown in
As shown in
As shown in
As shown in
Similar to the
While the heat transfer members have been shown having central portions and fillets with generally the same geometric shape, there may be variation between the two shapes. As an example, in
Conversely, in
Workers of skill in this art would recognize that by utilizing any number of possible combinations one can direct cooling air at an area that desirably receives more cooling air.
A gas turbine engine component under this disclosure could be said to include a body having an internal cooling passage with opposed walls and an array of heat transfer members attached to at least one of the opposed walls each with at least one fillet. There is an airflow direction through the cooling cavity such that the heat transfer members have a leading edge and a trailing edge. The at least one fillets have a leading edge and a trailing edge. A fillet portion leading edge is asymmetric relative to a fillet portion trailing edge to control an air flow direction towards downstream ones of the heat transfer members in the array.
A gas turbine engine component under this disclosure could also be said to include a body having an internal cooling passage with opposed walls and a heat transfer member attached to at least one of the opposed walls at a fillet. There is an airflow direction through the cooling cavity such that the heat transfer member has a leading edge and a trailing edge. The at least one fillet has a leading edge and a trailing edge. A fillet portion leading edge is asymmetric relative to a fillet portion trailing edge. The heat transfer components are attached to each of the spaced walls and there are two of the at least one fillets. Each of the two fillets having a leading edge portion which is asymmetric from a trailing edge portion. The two fillets are asymmetric relative to each other. The heat transfer components have a leading edge of one of the at least two fillets attached to one of the at least two walls being small and a leading edge fillet portion of the other of the fillets is attached to a second of the walls being relatively large. A trailing edge portion of the fillet attached to the first of the walls being relatively large and a trailing edge portion of the second of the fillets is attached to the second of the walls being relatively small such that cooling air is directed to the second of the walls.
A gas turbine engine under this disclosure could be said to include a compressor section delivering compressed air into a combustor. The combustor is configured to mix fuel with compressed air and ignite the mixture. Products of the combustion are configured to pass over a turbine section. The turbine section includes a plurality of components with at least one of the components being provided. A gas turbine engine component includes a body having an internal cooling passage with opposed walls and an array of heat transfer members attached to at least one of the opposed walls each with at least one fillet. There is an airflow direction through the cooling cavity such that the heat transfer members have a leading edge and a trailing edge. The at least one fillets have a leading edge and a trailing edge. A fillet portion leading edge is asymmetric relative to a fillet portion trailing edge to control an air flow direction towards downstream ones of the heat transfer member in the array.
While embodiments have been disclosed, a worker of ordinary skill in this art would recognize that modification would come within the scope of this disclosure. For that reason the following claims should be studied to determine the true scope and content of this disclosure.