Exhaust collector conversion system and method

Abstract

To provide a system with a tunnel that enables a particular exhaust system (e.g., an exhaust collector) designed for a larger turbine engine to be used with a different turbine engine by changing an interface between the tunnel and a turbine frame.SOLUTION: A system includes an exhaust collector tunnel (32) configured to be installed in an exhaust collector (30) of a gas turbine (12). The exhaust collector tunnel (32) has a tunnel wall (33) configured to extend around a turbine shaft (17, 19) of the gas turbine (12). The tunnel wall (33) has a variable diameter (98) along at least a portion of a length of the exhaust collector tunnel (32).SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The subject matter disclosed herein relates to turbine systems, and more particularly to systems and methods for turbine systems with exhaust collectors. [Background technology]

[0002] Power plants, such as combined cycle power plants, often employ gas turbine engines. Gas turbine engines combust fuel to produce hot combustion gases that flow through a turbine to drive a load, such as a generator. Exhaust gases exit the turbine at high velocity and temperature and enter an exhaust collector. Unfortunately, exhaust collectors are typically only compatible with one type of turbine engine. Summary of the Invention

[0003] Certain embodiments commensurate in scope with the claimed subject matter are summarized below. These embodiments are not intended to limit the scope of the claimed subject matter, but rather merely to provide a brief outline of possible forms of the subject matter. Indeed, the subject matter may encompass a variety of forms that may be similar to or different from the embodiments set forth below.

[0004] In a first embodiment, a system includes an exhaust collector tunnel configured to mount within an exhaust collector of a gas turbine, the exhaust collector tunnel having a tunnel wall configured to extend around a turbine shaft of the gas turbine, the tunnel wall having a variable diameter along at least a portion of the length of the exhaust collector tunnel.

[0005] In a second embodiment, a system includes an exhaust collector configured to couple to a gas turbine. The exhaust collector includes an exhaust collector frame, an exhaust diffuser disposed within the exhaust collector frame, a diverging section disposed within the exhaust collector frame downstream from the exhaust diffuser, and an exhaust collector tunnel disposed within the exhaust collector frame between the exhaust diffuser and the diverging section. The exhaust collector tunnel has tunnel walls configured to extend around a turbine shaft of the gas turbine. The tunnel walls have a variable diameter along at least a portion of the length of the exhaust collector tunnel.

[0006] In a third embodiment, a method includes installing an exhaust collector tunnel within an exhaust collector of a gas turbine, the exhaust collector tunnel having a tunnel wall configured to extend around a turbine shaft of the gas turbine, the tunnel wall having a variable diameter along at least a portion of a length of the exhaust collector tunnel.

[0007] These and other features, aspects, and advantages of the present subject matter will be better understood from the following detailed description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts throughout. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram of an embodiment of a gas turbine power plant having an exhaust collector assembly that can be modified (e.g., retrofitted) with a number of different tunnels, diffusers, seals, and mounts. [Figure 2] 2 is a cross-sectional view of one embodiment of the exhaust collector assembly of FIG. 1 illustrating a retrofit kit having tunnels (eg, fixed diameter tunnels) that can be used to retrofit the exhaust collector assembly. [Figure 3] 3 is a partial cross-sectional view of the exhaust collector assembly of FIG. 2 illustrating one embodiment of a turbine connection assembly. [Figure 4]3 is a partial cross-sectional view of the exhaust collector assembly of FIG. 2 illustrating one embodiment of a diffuser connection assembly. [Figure 5] 2 is a cross-sectional view of one embodiment of the exhaust collector assembly of FIG. 1 illustrating a retrofit kit having tunnels (eg, variable diameter tunnels) that can be used to retrofit the exhaust collector assembly. [Figure 6] 6 is a partial cross-sectional view of the exhaust collector assembly of FIG. 5 illustrating one embodiment of a turbine connection assembly. [Figure 7] FIG. 6 is a partial cross-sectional view of the exhaust collector assembly of FIG. 5 showing one embodiment of a diffuser connection assembly. [Figure 8] 2 is a cross-sectional view of one embodiment of the exhaust collector assembly of FIG. 1 illustrating a retrofit kit having a tunnel (eg, a stepped tunnel) that can be used to retrofit the exhaust collector assembly. [Figure 9] 9 is a flowchart of a method of removing a portion of an exhaust collector assembly in preparation for retrofitting using one of the retrofit kits of FIGS. 2-8. [Figure 10] 9 is a flowchart of a method of modifying the exhaust collector assembly of FIG. 1 by installing one of the retrofit kits of FIGS. 2-8. DETAILED DESCRIPTION OF THE INVENTION

[0009] Described below are one or more specific embodiments of the present subject matter. While an effort is made to provide a concise description of these embodiments, it may not be possible to describe all features of an actual implementation. It should be understood that, like any engineering or design project, the development of an actual implementation will require numerous implementation-specific decisions to be made to achieve the developer's specific goals, including adherence to system- and business-related constraints that may vary from implementation to implementation. Moreover, it should be understood that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill in the art having the benefit of this disclosure.

[0010] When introducing elements of various embodiments of the present subject matter, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the element. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0011] Disclosed embodiments include a retrofit kit for use with an exhaust collector of a gas turbine engine system. The retrofit kit includes one or more diffusers, each having a different size and interface, and a tunnel connected to a diverging section (e.g., conical section, deflector section) of the exhaust collector and a turbine frame via a combination of connecting structures (e.g., bolts, brackets) and one or more enlarged seal assemblies (e.g., circumferential grooves, circumferential seal segments, bolts, etc.). The tunnel may pass through the diffuser section of the gas turbine engine so as to be concentric with the diffuser section. That is, the tunnel (e.g., a bore) may be insulated and connected to the exhaust collector frame, extend through the collector chamber, pass through the exhaust diffuser, and connect to the gas turbine engine. The tunnel may surround a linkage (e.g., a coupling between the gas turbine shaft and the load shaft) to insulate the linkage from hot gases. The tunnel may be a retrofit or an original part of the gas turbine engine. For example, disclosed embodiments include a retrofit kit that includes an exhaust collector tunnel that allows a particular exhaust system (e.g., exhaust collector) designed for a larger turbine engine to be used with another turbine engine by changing the interface between the exhaust collector tunnel and the gas turbine frame that is used to connect the tunnel to the gas turbine engine.

[0012] The retrofit kit reduces exhaust gas leakage using one or more seal carriers. The tunnel has a shape designed to transition from the gas turbine engine to the diverging section (e.g., conical section, deflector section) of the exhaust collector. For some gas turbine engine embodiments, the tunnel shape may be cylindrical (e.g., straight annular wall) from the gas turbine engine to the diverging section. However, for other gas turbine engine embodiments, the tunnel shape may be variable (e.g., variable diameter annular wall) from the gas turbine engine to the diverging section. For example, the tunnel annular wall may gradually expand or contract from the gas turbine engine to the diverging section. The tunnel annular wall may be frustoconical, curved annular, stepped annular (e.g., annular wall with multiple diameter steps), or a combination thereof. As a result, the retrofit kit enables an exhaust collector designed for a larger gas turbine engine to be used with other types of gas turbine engines (e.g., smaller engines) without requiring complex modifications to the gas turbine engine power plant's exhaust collector enclosure or other packaging enclosure. For example, the retrofit kit may allow for the direct installation of a tunnel between an existing exhaust collector and the gas turbine frame. Although retrofit kits are currently contemplated for gas turbine engines, the disclosed embodiments are not limited to retrofit kits.

[0013] Turning now to the drawings, and referring initially to FIG. 1 , a diagram of a gas turbine engine power plant 10 is shown. A gas turbine engine 12 (or gas turbine), for example, an aeroderivative gas turbine engine, is coupled to an exhaust collector assembly 14. The diagram also shows a generator 16 coupled to the turbine engine 12 via a linkage 18 (e.g., a rotary or shaft coupling). The gas turbine engine 12, exhaust collector assembly 14, and generator 16 may be rigidly mounted to a sliding platform 20. An air intake and filtration system 22 may provide clean air for combustion. The air is compressed in a compressor section of the gas turbine engine 12 and mixed with a liquid fuel or a gaseous fuel, such as natural gas. The mixture is then combusted in a combustion chamber of the gas turbine engine 12. Hot, compressed gases resulting from the combustion of the mixture then pass through a number of turbine blades within the gas turbine engine 12. The hot, compressed gases rotate the turbine blades, causing the linkage 18 to rotate. Rotation of the linkage 18 may drive a load, such as a generator 16, as shown.

[0014] In one embodiment, hot gases exit the gas turbine engine 12 axially and enter an exhaust collector assembly 14 downstream from the gas turbine engine 12. The gas turbine engine 12 converts a portion of the energy in the hot gases into rotational motion. However, some useful energy may still remain in the hot exhaust gases. Therefore, the exhaust collector assembly 14 may capture and route the hot exhaust gases for further use, for example, by a heat recovery steam generator (HRSG). The HRSG may use the hot exhaust gases to generate steam for use in steam generators and / or other equipment within the power plant 10. The hot gases exiting the exhaust collector assembly 14 are flowing at high velocities and may contain high temperatures. Using the embodiments described in more detail below with respect to FIGS. 2-10 , an exhaust collector assembly 14 designed for a first gas turbine engine (e.g., a first power turbine) may be used with a second gas turbine engine (e.g., a second power turbine). The first and second gas turbine engines may differ in model number, physical size, power output, and turbine outlet or exhaust collector connection geometry. However, the disclosed embodiments address these differences by adapting or modifying the exhaust collector assembly 14 for use with a desired gas turbine engine.

[0015] FIG. 2 illustrates a perspective view of an embodiment of an exhaust collector 30 of a gas turbine system 10, where the exhaust collector 30 is coupled to a tunnel 32 (e.g., an exhaust collector tunnel or a shaft connection tunnel). To clarify the description of the features of the tunnel 32, the turbine 12, linkage 18, and air intake and filtration system 22 of the gas turbine system 10 are not fully shown in FIG. 2 . Components of the gas turbine engine system 10, including the exhaust collector 30, may be disposed within one or more frames 34. The exhaust collector 30 is coupled to a diffuser 36 that is downstream of the turbine 12 relative to an inlet axis (i.e., turbine axis 38). The diffuser 36 is configured to couple with an outer wall of the turbine 12 (e.g., defining an outer boundary of the exhaust flowpath), and the tunnel 32 is configured to couple with an inner wall of the turbine 12 (e.g., defining an inner boundary of the exhaust flowpath).

[0016] The illustrated exhaust diffuser 36 has an annular wall 40 that gradually increases in diameter in a downstream exhaust flow direction 42 from the gas turbine engine 12 toward the exhaust collector 30. The annular wall 40 can be described as a diverging, or expanding, annular wall that widens away from a longitudinal axis 44 in the downstream exhaust flow direction 42. The annular wall 40 can be linearly expanding (e.g., a frustoconical wall) and / or curvilinearly expanding (e.g., a curved annular wall or a bell-shaped wall). A smaller diameter end 46 of the diffuser 36 is coupled to the gas turbine engine 12 (as shown). The diffuser 36 diffuses (e.g., widens and slows) the axial flow of exhaust gases exiting the gas turbine engine 12. The exhaust collector 30 receives the exhaust flow from the diffuser 36 along an inlet axis into a collector chamber 37.

[0017] The exhaust collector 30 is disposed within an exhaust collector frame 34 (e.g., an enclosure) that includes a right wall 48, a top wall 50, a left wall 52, a bottom wall 54, a rear wall 56, and a front wall 58. A diverging portion 60 (e.g., a diverging annular wall or wall) may protrude axially into the exhaust collector 30 from the left wall 52. The diverging portion 60 may have a constant or substantially constant angle (e.g., a deflector portion or a frustoconical wall) and / or a variable angle (e.g., a curved annular wall, such as a bell-shaped wall) relative to the longitudinal axis 44. For example, the angle may be on the order of 20 to 70 degrees, 30 to 60 degrees, or 40 to 50 degrees. The diverging portion 60 may be used, for example, to radially disperse a portion of the gas flow so that the gas flow does not directly impinge on the left wall 52 in the same axial direction. As shown, the diverging section 60 widens in the downstream direction 42 along the longitudinal axis 44 , thereby gradually redirecting the exhaust flow from an axial direction 62 to a radial direction 64 .

[0018] The tunnel 32 may be insulated and connected to the diverging section 60, extend through the exhaust collector 30, pass through the diffuser 36, and be connected to the gas turbine engine 12 via a turbine frame 66 (see FIG. 3 ). The insulated tunnel 32 may include an annular wall 33 having one or more walls or layers of the same or different materials. For example, the annular wall 33 may include an inner annular wall 68, an outer annular wall 70, and one or more layers of insulation 69 between the inner and outer annular walls 68 and 70. The tunnel 32 may be coaxial with the longitudinal axis 44, for example, approximately at the axis of the inner hollow region of the diffuser 36. The tunnel 32 may pass through a diffuser opening 72 at one end and connect to the turbine frame 66. The tunnel 32 may surround the linkage 18 (e.g., the coupling between the shafts 17 and 19) to insulate the linkage 18 from the hot gases. Shaft 17 may be coupled to gas turbine engine 12 and shaft 19 may be coupled to a load, such as generator 16 .

[0019] The tunnel 32 may be removably coupled to the divergent portion 60 and the diffuser opening 72. Removing the tunnel 32 allows it to be replaced with another tunnel (see FIGS. 5 and 8 ), thereby changing the interface 74 between the tunnel 32 and the turbine 12. Changing the interface 74 allows the exhaust collector 30 to be used with multiple gas turbine engines by retrofitting the divergent portion 60 of the exhaust collector 30 to the gas turbine engine 12 with different tunnels 32. For example, the same divergent portion 60 can be used in the exhaust collector 30 for a variety of different gas turbine engines 12, and the tunnel 32 changes shape to transition from the same divergent portion 60 to different shapes for the various gas turbine engines 12. Indeed, by selecting the appropriate tunnel 32, the interface between the tunnel 32 and the gas turbine engine 12 can be enlarged (e.g., larger in diameter) or reduced (e.g., smaller in diameter) to suit the particular gas turbine engine 12 for which the exhaust collector 30 is intended. Thus, depending on the shape of the gas turbine engine 12 (eg, larger or smaller diameter), the annular wall 33 of the tunnel 32 may have various shapes.

[0020] As described above, the annular wall 33 of the tunnel 32 may have a constant diameter (e.g., a cylindrical wall) or a variable diameter (e.g., a tapered or diverging annular wall) in the direction of flow 42 from the gas turbine engine 12 to the diverging section 60. For example, a variable diameter annular wall 33 may include a linearly varying annular wall (e.g., a frustoconical wall), a curvilinearly varying annular wall (e.g., a curved annular wall), or a stepped annular wall (e.g., an annular wall having multiple steps, each with a different diameter). Depending on the particular application, the annular wall 33 may have any one or more of the aforementioned shapes in various combinations with each other. In the illustrated embodiment, the tunnel 32 has a substantially straight or uniform shape (e.g., a cylindrical wall 33) having a constant or substantially constant diameter (e.g., a diameter that varies by less than 1 percent) and is disposed coaxially with the longitudinal axis 44. The tunnel 32 is removably coupled to the diverging section 60 and the turbine frame 66. At the divergent section 60, a first end 76 of the tunnel 32 is secured to the divergent section 60 via a set of tunnel flanges 78 (e.g., circumferentially spaced flanges and / or annular flanges). The tunnel flanges 78 are bolted to the divergent section 60 and are used to secure these components together via an appropriate number of fasteners, such as threaded bolts 75. The tunnel 32 passes through the diffuser 36, and a second end 79 of the tunnel 32 is secured to the turbine frame 66 via a turbine connection assembly 77. FIG. 3 shows a partial cross-sectional view of the turbine connection assembly 77. The turbine connection assembly 77 may include a set of turbine frame flanges 80 (e.g., circumferentially spaced flanges and / or annular flanges). The second end 79 of the tunnel 32 is bolted to the turbine frame 66 and is used to secure the second end 79 of the tunnel 32 to the turbine frame 66. The second end 79 of the tunnel 32 may include a first seal 82 (e.g., a circumferential seal or annular seal) disposed in an opening in a first seal groove 86 (e.g., a circumferential seal groove or annular seal groove).The seal 82 also includes one or more segments 84 (e.g., circumferential seal segments) circumferentially arranged about the longitudinal axis 44 to form a 360-degree structure (e.g., an annular seal). The seal 82 may be decoupled at the groove ends to allow the seal 82 to move freely within the opening of the first seal groove 86. The seal 82 may reduce leakage of hot exhaust gases, reducing the likelihood of hot exhaust gases entering the tunnel 32.

[0021] The diffuser 36 is coupled to the exhaust collector frame 34 via a diffuser connection assembly 89. FIG. 4 shows a partial cross-sectional view of the diffuser connection assembly 89. The diffuser connection assembly 89 may include a set of exhaust enclosure flanges 88 (e.g., circumferentially spaced flanges and / or annular flanges). The exhaust enclosure flanges 88 are fastened to the exhaust collector frame 34 via a plurality of fasteners (e.g., threaded bolts 75) used to secure these components together. The exhaust enclosure flanges 88 may include a second seal groove 90 (e.g., a circumferential seal groove or annular seal groove). One or more second seal segments 92 (e.g., circumferential seal segments) disposed along the outer surface 41 of the diffuser 36 may be fastened to the second seal segments 92 (e.g., via threaded bolts) to reduce leakage of hot exhaust gases. The second seal segments 92 may be circumferentially disposed around the diffuser 36 to form a 360-degree structure (e.g., an annular seal). The diffuser 36 may also be coupled to the turbine frame 66 upstream of the exhaust enclosure flange 88 via a set of outer diffuser flanges 95 (e.g., circumferentially spaced flanges and / or annular flanges), which are fastened to an outer turbine flange connection 96 via a number of fasteners (e.g., threaded bolts 75), securing these components together.

[0022] As described above, the tunnel 32 passes through the diffuser 36. In the illustrated embodiment, the tunnel 32 and the diffuser 36 are not directly connected to one another via radial struts, joints, or other support structures. The absence of radial struts, joints, and other support structures may allow the tunnel 32 to be more easily removed from the exhaust collector frame 34. Furthermore, the relative size of the tunnel 32 to the diffuser 36 may allow the tunnel 32 to be more easily removed. In one embodiment, the diameter 98 (e.g., inner or outer diameter) of the tunnel 32 may be any suitable size, such as 14 to 54 inches, 20 to 48 inches, 24 to 44 inches, or any specific diameter therebetween, and the diameter 100 (e.g., inner or outer diameter) of the diffuser 36 may be any suitable size, such as 34 to 136 inches, 48 ​​to 122 inches, 60 to 110 inches, or any specific diameter therebetween.

[0023] FIG. 5 is a cross-sectional view of the exhaust collector 30 of the gas turbine system 10 of FIGS. 1 and 2 , where the exhaust collector 30 has been modified (e.g., retrofitted) with another embodiment of the tunnel 32. The components of the exhaust collector frame 34 and the diverging portion 60 are substantially the same as those described above with reference to FIG. 2 , and therefore, a description of these components will not be repeated. In the illustrated embodiment, the tunnel 32 has a tapered shape 102 along the annular wall 33 from the first end 76 of the tunnel 32 to the second end 79 of the tunnel 32. The angle 104 of the tapered shape 102 may be approximately 2 to 40 degrees, 3 to 35 degrees, 4 to 30 degrees, or 5 to 25 degrees along the annular wall 33. In certain embodiments, the angle 104 may be greater than a minimum angle of 1, 2, or 3 degrees, or less than a maximum angle of 10, 15, 20, 25, or 30 degrees, or any combination of these minimum and maximum angles. Angle 104 may be constant or substantially constant (e.g., less than 1 degree deviation) along some or all of the length between first end 76 and second end 79 (e.g., at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 100% of the length). When angle 104 is constant or substantially constant, annular wall 33 of tunnel 32 can be described as a tapered annular wall (or a tapered annular wall portion if it is less than the entire length of annular wall 33). Alternatively or additionally, angle 104 may vary (e.g., vary curvedly by at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 degrees) along some or all of the length between first end 76 and second end 76 (e.g., at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% of the length). For example, if angle 104 varies curvedly, annular wall 33 of tunnel 32 may be described as a curved annular wall (or curved annular wall portion, if less than the entire length of annular wall 33). Annular wall 33 may reduce and / or spread stress along tunnel 32 by improving the capacity of anticipated high-stress areas of walls 68, 70.The first end 76 of the tunnel 32 may be connected to the diverging portion 60 as described above with reference to Figure 2. That is, the first end 76 of the tunnel 32 may be connected to the diverging portion 60 via a set of tunnel flanges 78 (e.g., circumferentially spaced flanges and / or annular flanges).

[0024] FIG. 6 is a partial cross-sectional view of another embodiment of a turbine connection assembly 77 that can be used with the tapered tunnel 32 of FIG. 5 or the tunnel 32 shown in FIGS. 3 and 8 . In the illustrated embodiment, a second end 79 of the tapered tunnel 32 may be coupled to a turbine frame bracket 80 via one or more fasteners (e.g., threaded bolts 75). The second end 79 of the tunnel 32 and the turbine frame bracket 80 may form a first seal groove 86 (e.g., an annular seal groove) for receiving a seal 82 (e.g., an annular seal or a circumferentially segmented seal). For example, the seal 82 may also include multiple circumferential seal segments that are held in place in part by the force of the turbine frame bracket 80.

[0025] FIG. 7 is a partial cross-sectional view of another embodiment of a diffuser connection assembly 89 usable with the tapered tunnel 32 of FIG. 5 or the tunnel 32 shown in FIGS. 3 and 8 . The diffuser connection assembly 89 may include a lip 93 connected (e.g., by a welded connection) to the outer surface 41 of the diffuser 36. The lip 93 (e.g., an annular lip) extends circumferentially around the outer surface 41 of the diffuser 36. The lip 93 may also include seal segments 92 circumferentially disposed around the outer surface 41 of the diffuser 36. The diffuser connection assembly 89 includes at least two diffuser brackets 94 (e.g., circumferentially spaced brackets and / or annular brackets) to form a groove 90 (e.g., an annular seal groove) that receives the seal segments 92. The diffuser brackets 94 may be coupled to each other via fasteners, such as threaded bolts 75. The diffuser bracket 94 may also be coupled to the exhaust enclosure flange 88.

[0026] 5 , the diameter 98 (e.g., inner or outer diameter) of the first end 76 of the tunnel 32 is different in size (e.g., larger) than the diameter 106 (e.g., inner or outer diameter) of the second end 79 of the tunnel 32. Thus, the annular wall 33 of the tunnel 32 has a variable diameter between the first end 76 and the second end 79. The tapered tunnel 32 allows for a variable interface between the second end 79 of the tunnel 32 and the turbine frame 66. For example, the ratio of the diameter 98 (e.g., inner or outer diameter) of the first end 76 to the diameter 106 (e.g., inner or outer diameter) of the second end 79 is greater than 1, such as at least 1.05 or greater, 1.1 or greater, 1.15 or greater, 1.2 or greater, 1.25 or greater, 1.3 or greater, 1.45 or greater, or 1.5 or greater. The tapered tunnel 32 allows the diverging section 60 (e.g., the same diverging section as in FIG. 2 ) to be used with another diffuser 36 of another gas turbine engine 12 (e.g., a lower-power turbine or other suitable turbine engine). For example, the diameter 106 and angle 104 may be specifically selected to allow retrofitting with another gas turbine engine 12 and / or another diffuser 36. Accordingly, the ratio of the diameter 100 (e.g., inner or outer diameter) of the diffuser 36 to the diameter 106 (e.g., inner or outer diameter) at the second end 79 may be, for example, 1.5 or greater, 1.75 or greater, 2 or greater, 2.25 or greater, 2.5 or greater, 2.75 or greater, or 3 or greater.

[0027] In the illustrated embodiment, the diameter 98 (e.g., inner or outer diameter) of the first end 76 of the tunnel 32 may be any suitable size, such as 12 to 50 inches, 18 to 44 inches, 22 to 40 inches, or any specific diameter therebetween, and the diameter 106 (e.g., inner or outer diameter) of the second end 79 of the tunnel 32 may be any suitable size, such as 8 to 48 inches, 14 to 42 inches, 20 to 38 inches, or any specific diameter therebetween. In the illustrated embodiment, the diameter 100 (e.g., inner or outer diameter) of the diffuser 36 may be any suitable size, such as 34 to 136 inches, 48 ​​to 122 inches, 60 to 110 inches, or any specific diameter therebetween. As mentioned above, the tunnel 32 and the diffuser 36 are not directly connected to each other via radial struts, couplings, or other support structures, which allows the tunnel 32 to be more easily removed from the exhaust collector frame 34.

[0028] FIG. 8 is a cross-sectional view of the exhaust collector 30 of the gas turbine system 10 of FIGS. 1, 2, and 5, where the exhaust collector 30 has been modified (e.g., retrofitted) with another embodiment of the tunnel 32. The components of the exhaust collector frame 34 and the diverging portion 60 are substantially the same as those described above with reference to FIGS. 2 and 5, and therefore, a description of these components will not be repeated. In the illustrated embodiment, the exhaust collector 30 of FIG. 8 has a turbine connection assembly 77 as shown in FIG. 9 and a diffuser connection assembly 89 as shown in FIG. 10. However, in some embodiments, the exhaust collector 30 of FIG. 8 may have a turbine connection assembly 77 as shown in FIG. 3 and / or a diffuser connection assembly 89 as shown in FIG. 4.

[0029] In the illustrated embodiment, tunnel 32 has a step 108 (e.g., an annular step or an abrupt diameter change, such as a stepped wall portion) along annular wall 33 between first end 76 of tunnel 32 and second end 79 of tunnel 32. Step 108 transitions between adjacent wall portions 107 and 109 of annular wall 33 of tunnel 32. While FIG. 8 shows only one step 108, embodiments of tunnel 32 may have any number of steps 108 between adjacent wall portions 107 and 109 (e.g., one, two, three, four, five, six, or more annular steps). Adjacent wall portions 107 and / or wall portions 109 may be cylindrical or tapered. Each step 108, such as the illustrated step 108, may change (e.g., reduce) the diameter of the annular wall 33 by some dimension or percentage from wall 107 to wall 109. For example, each step 108 may reduce the diameter 110 (e.g., inner or outer diameter) of the annular wall 33 by at least 1 inch, 2 inches, 3 inches, 4 inches, 5 inches, 6 inches, 7 inches, 8 inches, 9 inches, 10 inches or more, or at least 1 percent, 2 percent, 3 percent, 4 percent, 5 percent, 6 percent, 7 percent, 8 percent, 9 percent, 10 percent or more relative to the diameter of the annular wall 33 immediately preceding the step 108 (e.g., at wall 107). In some embodiments, step 108 may have a reduced diameter 110 that is the same as diameter 106 of second end 79, or step 108 may have a reduced diameter 110 that is such that angle 104 of wall 107 is about 1 degree or less, 2 degrees or less, 3 degrees or less, 4 degrees or less, 5 degrees or less, 6 degrees or less, 7 degrees or less, 8 degrees or less, 9 degrees or less, or 10 degrees or less. Step 108 may also have an angle 111 (e.g., an acute angle) relative to longitudinal axis 44, such as between 15 and 90 degrees, 20 and 75 degrees, 30 and 60 degrees, or 40 and 50 degrees. In some embodiments, angle 111 of step 108 may be substantially the same as angle 61 of flared portion 60, also measured relative to longitudinal axis 44. However, the angle 111 of the step 108 may be different from the angle 61 of the flared portion 60 , such as a larger angle that transitions sharply to the smaller diameter 110 .

[0030] Similar to the embodiment shown in FIG. 5 , the diameter 98 (e.g., inner or outer diameter) of the first end 76 of the tunnel 32 is larger than the diameter 106 (e.g., inner or outer diameter) of the second end 79 of the tunnel 32. Thus, the step 108 allows for varying the interface between the second end 79 of the tunnel 32 and the frame 66. In the illustrated embodiment, the first end 76 of the tunnel 32 has a diameter 98 (e.g., inner or outer diameter), such as 12 to 50 inches, 18 to 44 inches, 22 to 40 inches, or any particular diameter therebetween. At the initial step 108, the tunnel diameter is reduced to a tunnel diameter 110, such as 8 to 48 inches, 14 to 42 inches, 20 to 38 inches, or any particular diameter therebetween. The inner diameter 106 of the second end 79 of the tunnel 32 is 10 to 46 inches, 16 to 40 inches, 22 to 36 inches, or any particular diameter therebetween. The illustrated tunnel 32 (e.g., a stepped tunnel) is disposed between the diverging portion 60 and another diffuser 36 of another gas turbine engine 12. In the illustrated embodiment, the diameter 100 (e.g., inner or outer diameter) of the second diffuser 36 may be any suitable size, such as 34 to 136 inches, 48 ​​to 122 inches, 60 to 110 inches, or any diameter therebetween.

[0031] FIG. 9 illustrates a method 200 for removing a portion of the exhaust collector assembly 14 (e.g., the first tunnel 32 and the first diffuser 36) in preparation for retrofitting using one of the retrofit kits of FIGS. 2-8 according to an embodiment disclosed herein. The method 200 includes disengaging the tunnel 32 from the power turbine 12 (block 202). The method 200 includes removing the rear wall 56 of the packaging enclosure 30 (block 204). Removing the rear wall 56 of the exhaust enclosure 30 allows the tunnel 32 and the diffuser 36 to be removed from the exhaust enclosure 30. The method 200 includes decoupling the tunnel 32 from the diverging portion 60 (e.g., the deflector portion) (block 206). Decoupling the tunnel 32 may include unbolting the first end 76 of the tunnel 32 from the diverging portion 60 (e.g., the deflector portion). The method 200 includes disengaging the seal 82 of the tunnel 32. Disengaging the seal 82 may include removing the turbine frame 80 from the second end 79 of the tunnel 32. The method 200 includes removing the attached tunnel 32 from the exhaust collector 30 along the axis 38 (block 208). The method 200 includes decoupling the diffuser 36 from the turbine 12 (block 210). Decoupling the diffuser 36 may include removing the diffuser bracket 94 from the exhaust enclosure flange 88. The method includes disengaging the diffuser seal 92 (block 212). The method 200 includes removing the attached diffuser 36 along the axis 38.

[0032] FIG. 10 illustrates a method 300 for modifying the exhaust collector assembly 14 of FIG. 1 by installing one of the retrofit kits of FIGS. 2-8 (e.g., by installing another replacement tunnel 32 and another replacement diffuser 36 after performing method 200 of FIG. 9 ) in accordance with an embodiment disclosed herein. Method 300 may include installing the replacement diffuser 36 within the exhaust enclosure 30 (block 302). Method 300 further includes coupling the replacement diffuser 36 in place by bolting the replacement diffuser 36 to the turbine frame 66 via one or more bolts and flange connections or brackets to secure the small diameter end 46 of the diffuser 36 to the turbine frame 66 (block 304). Method 300 includes engaging a replacement seal 92 of the replacement diffuser 36 (block 306). Method 300 includes installing the replacement tunnel 32 (block 308). The method 300 includes coupling a first end 76 of the tunnel 32 to the diverging portion 60 (e.g., the deflector portion) (block 310). Coupling the first end 76 of the tunnel 32 to the diverging portion 60 (e.g., the deflector portion) may include bolting the first end 76 of the tunnel 32 to one or more tunnel flanges 78 at the diverging portion 60. The method 300 includes engaging a seal 82 at an opposite second end 79 of the tunnel 32 (block 312). Once the tunnel 32 is installed, the method 300 includes replacing the rear wall 56 of the exhaust enclosure 30 (block 314). The above-described methods 200 and 300 can be used to modify (e.g., retrofit) the exhaust collector assembly 14 to switch between the embodiments shown in Figures 1-8 so that the exhaust collector assembly 14 can be used with any desired gas turbine engine 12 (e.g., interchange between different sizes, models, or types having different dimensions when connected to the exhaust collector assembly 14).

[0033] Technical effects of the present invention include the availability of a retrofit kit including a tunnel that allows a particular exhaust system (e.g., exhaust collector) designed for a larger turbine engine to be used with another turbine engine by changing the interface between the tunnel and the turbine frame. The retrofit kit includes one or more diffusers, each having a different size and interface, a tunnel, and one or more seal assemblies for reducing exhaust gas leakage. The tunnel may have walls that are straight, tapered, curved, stepped, or any other suitable shape to accommodate the fit between the exhaust collector and the turbine frame. As a result, the retrofit kit allows an exhaust collector designed for a larger gas turbine engine to be used with another type of gas turbine engine without requiring significant modifications to the exhaust collector frame or other enclosures for various components of the gas turbine engine power plant.

[0034] This specification uses examples to disclose the claimed subject matter, including the best mode, and also to enable any person skilled in the art to practice such subject matter, including making and using any devices or systems and performing any related methods. The patentable scope of the subject matter is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims. [Explanation of symbols]

[0035] 10 Gas turbine engine power plants, gas turbine engine systems 12 Gas turbine engine, power turbine 14 Exhaust Collector Assembly 16. Generator 17 Shaft 18 Link mechanism 19 Shaft 20 Sliding Platform 22 Air Intake and Filtration System 30 Exhaust collector, exhaust enclosure 32 Tunnel 33 Annular wall, cylindrical wall 34 Exhaust collector frame 36 Diffuser 37 Collector Room 38 Turbine shaft 40 Circular Wall 41 Diffuser outer surface 42 directions 44 Longitudinal axis 46 Small diameter end of diffuser 48 Right wall 50 Upper Wall 52 Left Wall 54 Bottom Wall 56 Back wall 58 Front wall 60 flared section 61 Angle of flared part 62 Axial 64 Radial 66 Turbine frame 68 Inner annular wall 69 Insulator Layer 70 Outer annular wall 72 Diffuser opening 74 Joint surface 75 Threaded Bolt 76 First end of the tunnel 77 Turbine Connection Assembly 78 Tunnel flange 79 Second End of Tunnel 80 Turbine frame bracket, turbine frame flange 82 First Seal 84 segments 86 First seal groove 88 Exhaust Enclosure Flange 89 Diffuser Connection Assembly 90 Second seal groove 92 Second seal segment, diffuser seal, replacement seal 93 Lip 94 Diffuser bracket 95 Outer diffuser flange 96 Outer turbine flange connection 98 diameter 100 diameter 102 Tapered shape 104 angle 106 diameter, inner diameter 107 Wall 108 Multilayered section 109 Wall section 110 diameter, tunnel diameter 111 Angle 200 ways 300 ways

Claims

1. A system (10) comprising an exhaust collector tunnel (32) configured to be mounted within an exhaust collector (30) of a gas turbine (12), the exhaust collector tunnel (32) comprising a tunnel wall (33) configured to extend around a turbine shaft (17, 19) of the gas turbine (12), the exhaust collector tunnel (32) including a first coupling portion extending at least partially into an exhaust diffuser and configured to be removably coupled to the gas turbine (12), and a second coupling portion configured to be removably coupled to a diverging portion downstream of the exhaust diffuser. an exhaust flow path extends through the exhaust diffuser and along a tunnel wall (33) and the diverging portion of the exhaust collector tunnel (32), the tunnel wall (33) having a variable diameter (98) along at least a portion of the length of the exhaust collector tunnel (32), the variable diameter including a tapered wall portion having an angle of 30 degrees or less with respect to a longitudinal axis of the exhaust collector tunnel (32) and a second wall portion having an angle different from the tapered wall portion, the tapered wall portion extending along at least 10 percent of the length of the exhaust collector tunnel (32).

2. A system (10) as described in claim 1, comprising a retrofit kit having one or more alternative exhaust diffusers including the exhaust diffuser, the exhaust collector tunnel, and one or more seal assemblies for reducing exhaust gas leakage, wherein the one or more alternative exhaust diffusers have different sizes and mating surfaces.

3. A system (10) as described in claim 1, comprising a plurality of alternative exhaust collector tunnels including the exhaust collector tunnel, the plurality of alternative exhaust collector tunnels having different shapes from one another to transition from the same flared section to different shapes for a plurality of different gas turbines including the gas turbine.

4. The system (10) described in claim 3, wherein the plurality of alternative exhaust collector tunnels include a plurality of turbine frame interface surfaces each formed to a different size for the plurality of different gas turbines.

5. The system (10) described in claim 1, wherein the exhaust collector tunnel includes a first end having the first connection portion and a second end having the second connection portion, and the portion of the exhaust collector tunnel having the variable diameter includes the first end.

6. The system (10) of claim 5, comprising the exhaust collector (30) having the exhaust diffuser (36) and the diverging portion (60).

7. 7. The system of claim 6, comprising the gas turbine configured to couple to the exhaust collector, the tunnel wall extending around the turbine shaft and a coupling configured to couple the turbine shaft to a load shaft of a load driven by the gas turbine.

8. A system (10) as described in claim 1, comprising an exhaust diffuser (36), wherein the exhaust collector tunnel (32) extends at least partially within the exhaust diffuser (36), the exhaust collector tunnel (32) is not directly connected to the exhaust diffuser (36), and the first connection portion of the exhaust collector tunnel is configured to be removably connected to a turbine frame of the gas turbine.

9. The system (10) of claim 1, wherein the angle of the tapered wall portion is smaller than the angle of the flared portion.

10. The system (10) of claim 1, wherein the angle of the tapered wall portion (102) has a substantially constant angle (104) relative to the longitudinal axis (44) of the exhaust collector tunnel (32).

11. The system (10) of claim 1, wherein the angle of the tapered wall portion (102) has a variable angle (104) relative to the longitudinal axis (44) of the exhaust collector tunnel (32).

12. The system (10) of any preceding claim, wherein the tapered wall portion (102) extends along at least 50% of the length of the exhaust collector tunnel (32).

13. A system (10) as described in claim 1, wherein the angle of the tapered wall portion is less than 20 degrees and the tapered wall portion extends along a length of at least 20 percent of the length of the exhaust collector tunnel.

14. A method (200, 300) comprising providing an exhaust collector tunnel (32) configured to be mounted within an exhaust collector (30) of a gas turbine (12), the exhaust collector tunnel (32) comprising a tunnel wall (33) configured to extend around a turbine shaft (17, 19) of the gas turbine (12), the exhaust collector tunnel (32) having a first coupling portion extending at least partially into an exhaust diffuser and configured to be removably coupled to the gas turbine (12), and a diverging portion downstream of the exhaust diffuser. and a second connection portion, wherein an exhaust flow path extends through the exhaust diffuser and along a tunnel wall (33) and the diverging portion of the exhaust collector tunnel (32), the tunnel wall (33) having a variable diameter (98) along at least a portion of the length of the exhaust collector tunnel (32), the variable diameter including a tapered wall portion having an angle of 30 degrees or less with respect to a longitudinal axis of the exhaust collector tunnel (32) and a second wall portion having an angle different from the tapered wall portion, the tapered wall portion extending along at least 10 percent of the length of the exhaust collector tunnel (32). Method (200, 300).

15. Providing the exhaust collector tunnel comprises: selecting the exhaust collector tunnel from a plurality of alternative exhaust collector tunnels, the plurality of alternative exhaust collector tunnels differing in shape from one another to transition from the same diverging section to different shapes of a plurality of different gas turbines, including the gas turbine; and The exhaust collector tunnel (32) is installed in the exhaust collector (30). Attaching The method (200, 300) of claim 14, comprising:

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