Patent Publication Number: US-10767864-B2

Title: Turbine cooled cooling air by tubular arrangement

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a non-provisional application claiming priority to U.S. Provisional Application No. 62/181,836 filed Jun. 19, 2015, which is hereby incorporated by reference in its entirety. 
    
    
     FIELD OF TECHNOLOGY 
     The present disclosure relates to a gas turbine engine implementing a tubular arrangement in a combustor for turbine cooled cooling air. 
     BACKGROUND 
     A gas turbine engine generally includes a compressor section, a combustor or combustor section, and a turbine section. The compressor section receives and compresses a flow of intake air. The compressed air then enters the combustor section in which a steady stream of fuel is injected, mixed with the compressed air, and ignited, resulting in high energy combustion gas, which is then directed to the turbine section. Some gas turbine engines may also include a source for providing a cooling fluid, such as air, within the engine, for example upstream of the turbine section and/or downstream of the compressor section. The cooling fluid may be circulated through the engine and a heat exchanger via a tube or conduit, which may be routed through the combustor. 
     The combustor generally includes an inner wall and an outer wall defining a combustion chamber there between, where the inner wall and the outer wall have different thicknesses for structural and pressure containment purposes. The compressed air discharged from the compressor section typically is at high temperatures, and therefore heats the combustor walls as it is introduced into the combustor. However, because of the different thicknesses, the inner wall and the outer wall may thermally grow at different rates. This, in turn, may affect or limit the implementation of any structures that interface with the walls, such as a tube or conduit within the combustion chamber that are through which the cooling fluid flows. 
     As such, there exists a need for a gas turbine engine that accounts for the differential thermal growth between the inner wall and the outer wall of the combustor. In particular, there exists a need for a gas turbine engine implementing a tubular arrangement for providing turbine cooling air such that the tubular arrangement may be provided in the combustion chamber and accommodates the differential thermal growth between the inner wall and the outer wall of the combustor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       While the claims are not limited to a specific illustration, an appreciation of the various aspects is best gained through a discussion of various examples thereof. Referring now to the drawings, exemplary illustrations are shown in detail. Although the drawings represent the illustrations, the drawings are not necessarily to scale and certain features may be exaggerated to better illustrate and explain an innovative aspect of an example. Further, the exemplary illustrations described herein are not intended to be exhaustive or otherwise limiting or restricted to the precise form and configuration shown in the drawings and disclosed in the following detailed description. Exemplary illustrations are described in detail by referring to the drawings as follows: 
         FIG. 1  illustrates a schematic view of an exemplary gas turbine engine employing the improvements discussed herein; 
         FIGS. 2 and 3  illustrate schematic partial, cross-sectional views of a combustor of the gas turbine engine of  FIG. 1  with a mobile conduit installed therein according to different exemplary approaches; 
         FIG. 4  illustrate an enlarged view of an upper floating joint at an outer wall of the combustor as implemented in the exemplary approach illustrated in  FIG. 2 ; 
         FIG. 5  illustrates an enlarged view of a lower floating joint at an inner wall of the combustor as implemented in the exemplary approaches illustrated in  FIGS. 2 and 3 ; 
         FIG. 6  illustrates an enlarged view of an upper gimbal joint at an outer wall of the combustor as implemented in the exemplary approach illustrated in  FIG. 3 ; 
         FIGS. 7 and 8  illustrate schematic diagrams of an alignment of multiple conduits according to different exemplary approaches; 
         FIG. 9  illustrates a schematic view of the mobile conduit with a double wall to accommodate an insulation feature of  FIGS. 2 and 3 ; and 
         FIG. 10  illustrates an exemplary method for implementing the exemplary approaches illustrated in  FIGS. 2 and 3 . 
     
    
    
     DETAILED DESCRIPTION 
     A gas turbine engine generally may circulate a cooling fluid, such as air, from the engine to a heat exchanger. An exemplary gas turbine engine may include at least one mobile conduit through which the cooling fluid may flow and that may be positioned in a combustor of the gas turbine engine. The combustor generally may include an inner wall and an outer wall defining a combustion chamber there between, and the inner wall and the outer wall may each have at least one opening into the combustion chamber. The gas turbine engine may have a first joint and a second joint that fluidly connect the at least one mobile conduit to the at least one opening in the inner wall and the at least one opening in the outer wall, respectively, such that the cooling fluid may flow from the opening in the outer wall to the opening in the inner wall through the at least one mobile conduit. The first joint and the second joint may enable multiple degrees of freedom of the at least one mobile conduit within the combustion chamber, for example, to account for different rates of expansion of the inner wall and the outer wall. The first joint and/or the second joint may be floating joints that allow for multiple angular degrees of freedom and a translational degree of freedom of respective ends of the at least one mobile conduit. Alternatively, the second joint may be a gimbal joint that allows for multiple angular degrees of freedom with no translational degree of freedom of a respective end of the at least one mobile conduit. 
     An exemplary method for implementing a conduit in the gas turbine engine as described above may include first providing a first opening in the inner wall of the combustor, and providing a second opening in the outer wall of the combustor. The method may then include fluidly connecting the conduit to the first opening via a first joint and to the second opening via the second joint such that the cooling fluid may flow through the conduit from the second opening to the first opening. As explained above, the first joint and the second joint may enable multiple degrees of freedom of the conduit within the combustion chamber. 
     Referring to the figures, an exemplary gas turbine engine  100  is shown in  FIG. 1 . The gas turbine engine  100  generally may include a  102 , a combustor or combustor section  103 , and a turbine section  104 . While the gas turbine engine  100  is depicted in  FIG. 1  as a multi-shaft configuration, it should be appreciated that the gas turbine engine  100  may be a single-shaft configuration as well. In addition, while the gas turbine engine  100  is depicted as a turbofan, it should further be appreciated that it may be, but is not limited to, a turbofan, a turboshaft, or a turboprop. The compressor section  102  may be configured to receive and compress an inlet air stream. The compressed air may then be mixed with a steady stream of fuel and ignited in the combustor  103 . The resulting combustion gas may then enter the turbine section  104  in which the combustion gas causes turbine blades to rotate and generate energy. 
     Referring to  FIGS. 2 and 3 , a partial section of the combustor  103  is shown. The combustor  103  generally may include an inner wall  110  and an outer wall  112  defining a combustion chamber  114  there between, and the pressure vessel inner wall  110  generally may be thinner than the structural outer wall  112 . The difference in thickness may vary depending upon the construction of the combustor  103 . For example, the outer wall  112  may be a composite outer wall, thereby having a thickness closer to that of the inner wall  112  than if the outer wall  112  is a structural outer wall. The relative thickness of the outer wall  112  with respect to the inner wall  110  may determine which approach illustrated in  FIG. 2  or  FIG. 3  may be implemented, as described in more detail below. The inner wall  110  may have a first opening  116 , and the outer wall  112  may have a second opening  118  into the combustion chamber  114 . The gas turbine engine  100  may include a tube  126  through which a cooling fluid, as represented by arrow  121 , is routed to the combustion chamber. The tube  126  may penetrate at least a portion of the second opening  118 , and may be secured to the outer wall  112  via a flange or bracket  128 . 
     The gas turbine engine  100  may also include a conduit  120  located within the combustion chamber  114  between the first opening  116  and the second opening  118 . The conduit  120  may enable the cooling fluid  121  to flow from the second opening  118  to the first opening  116 . The gas turbine engine  100  may further include a first joint  122  and a second joint  124   a,b  that fluidly connect the conduit  120  to the first opening  116  and the second opening  118 , respectively, such that the cooling fluid  121  may flow from the second opening  118  through the conduit  120  to the first opening  116 . The joints  122  and  124   a,b  generally may allow for multiple degrees of freedom, including angular and translational, and may include, but are not limited to, floating joints and gimbal joints. 
     In one exemplary approach depicted in  FIG. 2 , the first joint  122  and the second joint  124   a  may both be floating joints, as depicted in  FIGS. 4 and 5  and described in more detail below, that enable multiple angular degrees of freedom and a translational degree of freedom of respective ends of the conduit  120 . This configuration may be implemented when the thickness of the outer wall  112  is much greater than the thickness of the inner wall  110 , for example, when the outer wall  112  is a structural outer wall, as explained above. 
     In another exemplary approach depicted in  FIG. 3 , the first joint  122  may be a floating joint, as depicted in  FIG. 5 , and the second joint  124   b  may be a gimbal joint attached to an end of conduit  120 , as depicted in  FIG. 6 . The floating joint may again enable multiple angular degrees of freedom and a translational degree of freedom of the respective end of the conduit  120 , whereas the gimbal joint only enables angular degrees of freedom and no translational degree of freedom of the respective end of the conduit  120 . This configuration may be implemented when the thickness of the outer wall  112  is closer to that of the inner wall  110 , for example when the outer wall  112  is a composite outer wall, as explained above. 
     Referring to  FIGS. 4-6 , the first joint  122  and the second joint  124   a,b  are shown in more detail, where  FIGS. 4 and 5  depict the second joint  124   a  and the first joint  122 , respectively, as floating joints according to the configuration of  FIG. 2 , and  FIG. 6  depicts the second joint  124   b  as a gimbal joint according to the configuration of  FIG. 3 . In each configuration, the first joint  122  may include a tubular case  130  extending radially from the inner wall  110  into the combustion chamber  114  and around the first opening  116 . The first joint  122  may also include a spring seal  132  attached to the conduit  120  and configured to engage with the tubular case  130  to prevent any air from exiting the combustion chamber  114  through the first opening  116 , as well as to control the translational movement of the conduit  120 . 
     The second joint  124   a,b  may also include a tubular case  131   a,b  extending radially from the outer wall  110  and a spring seal  132  attached to the conduit  120 . In the configuration depicted in  FIGS. 2 and 4 , the tubular case  131   a  of the second joint  124   a , which may be a floating joint in this configuration, may be attached to the flange  128  and to the tube  126 . The second joint  124   a  may also include a retaining ring  134  within the tubular case  131   a  and configured to engage with the spring seal  132  after a certain amount of translational movement of the conduit  120  to ensure that the conduit  120  and the second joint  124   a  do not become disengaged from each other. In the embodiment depicted in  FIGS. 3 and 6 , the tubular case  131   b  of the second joint  124   b , which may be a gimbal joint as explained above, may be attached to an end of the conduit  120  such that only the other end of the conduit  120  may have translational movement when the inner wall  110  and outer wall  112  experience growth at separate rates. 
     Referring back to  FIGS. 2 and 3 , the conduit  120  may have different cross-sectional shapes, including but not limited to circular and oval. In addition, the conduit  120  may be a straight tube or have multiple bends. The shape and configuration of the conduit  120  may be dependent upon different factors, including, but not limited to, available space within the combustor  103 . Furthermore, the gas turbine engine  100  may include multiple conduits  120  arranged in a radial alignment with the outer wall  112 , as illustrated in  FIG. 7 , or in a non-radial alignment with the outer wall  112 , as illustrated in  FIG. 8 . While  FIGS. 7 and 8  show four conduits  120  spaced equally around the circumference of the combustor  103 , it should be appreciated that the gas turbine engine  100  may include any number of conduits  120  spaced apart from each other at any radial distance. 
     Referring now to  FIG. 9 , the gas turbine engine  100  may also include an outer sleeve  136  disposed around at least a portion of the conduit  120 . The outer sleeve  136  may be spaced apart from the conduit  120  such that there is an air gap  138  between the outer sleeve  136  and the conduit  120 . At least a portion of the air gap  138  may be filled with insulation  140 . Alternatively or additionally, the conduit  120  and/or the outer sleeve  140  may be coated with a thermal barrier  142 . 
     Referring now to  FIG. 10 , an exemplary method  200  for implementing the approaches illustrated in  FIGS. 2 and 3  is shown. Method  200  generally may begin at block  202  at which the openings  116  and  118  are provided in the inner wall  110  and the outer wall  112 , respectively, of the combustor  103 . The openings  116  and  118  may be provided such that the conduit  120 , installed at block  204 , has either a radial alignment with the outer wall  112 , as illustrated in  FIG. 7 , or a non-radial alignment with the outer wall  112 , as illustrated in  FIG. 8 . After block  202 , method  200  may then proceed to block  204  at which the conduit  120  may be fluidly connected to the first opening  116  and the second opening  118  via the first joint  122  and the second joint  124 . With respect to the first joint  122 , this may first include attaching or otherwise extending the tubular case  130  into the combustion chamber  114 , and attaching the spring seal  132  to an end of the conduit  120 . The conduit  120  with the spring seal  132  may then be inserted into the first opening  116  until the spring seal  132  and the tubular case  130  engage with each other. With respect to the second joint  124   a,b , the spring seal  132  may be attached to an end of the conduit  120 , which then may be inserted into the tubular case  131   a,b  of the second joint  124   a,b . When the joint  124   a  is a floating joint, a retaining ring  134  may then be provided to maintain the end of the conduit  120  within the tubular case  131   a . When the joint  124   b  is a gimbal joint, the tubular case  131   b  may be attached to the end of the conduit  120  such that there is no translational degree of freedom of that end of the conduit  120 . 
     After block  204 , method  200  may end. Method  200  may be repeated as many times as there are conduits  120  installed, for example four conduits  120  as illustrated in  FIGS. 7 and 8 . 
     In addition, method  200  may also include providing an outer sleeve  136  around at least a portion of the conduit  120 , providing insulation  140  in at least a portion of an air gap  138  between the outer sleeve  136  and the conduit  120 , and/or applying a thermal barrier  142  to at least a portion of the conduit  120  and/or the outer sleeve  136 . 
     With regard to the processes, systems, methods, heuristics, etc. described herein, it should be understood that, although the steps of such processes, etc. have been described as occurring according to a certain ordered sequence, such processes could be practiced with the described steps performed in an order other than the order described herein. It further should be understood that certain steps could be performed simultaneously, that other steps could be added, or that certain steps described herein could be omitted. In other words, the descriptions of processes herein are provided for the purpose of illustrating certain embodiments, and should in no way be construed so as to limit the claims 
     It will be appreciated that the aforementioned method and devices may be modified to have some components and steps removed, or may have additional components and steps added, all of which are deemed to be within the spirit of the present disclosure. Even though the present disclosure has been described in detail with reference to specific embodiments, it will be appreciated that the various modifications and changes can be made to these embodiments without departing from the scope of the present disclosure as set forth in the claims. The specification and the drawings are to be regarded as an illustrative thought instead of merely restrictive thought.