Inlet duct system for heat recovery steam generator

Abstract

A system (10) includes an exhaust diffuser system (22) for a heat recovery steam generator (HRSG) (16). The system (10) includes an inlet portion (23), a diffuser portion (24) extending axially from the inlet portion (23), and an outlet portion (26) fluidly coupled to an axially distal end of the diffuser portion (24), where an outlet region (252) of the outlet portion (26) is larger than an inlet region (254) of the inlet portion (23). The diffuser portion (24) includes a plurality of wall portions (272), and the plurality of wall portions (272) are incrementally angled with respect to an axial region (258) extending from the inlet portion (23) to the outlet portion (26). The system (10) may also include a gas turbine engine (12) coupled to the inlet portion (23) and an HRSG (16) coupled to the outlet portion (26).

Description

Technical Field

[0001] The subject matter disclosed herein generally relates to an inlet piping system for a heat recovery steam generator. Background Art

[0002] A heat recovery steam generator (HRSG) can draw in an exhaust flow via an inlet duct coupled to the HRSG, wherein the inlet duct is coupled to a gas turbine system. Unfortunately, the exhaust flow may separate from the inner surface of the inlet duct and may cause one or more vortices to form between the exhaust flow and the inner surface. This flow separation from the inner surface of the inlet duct causes pressure loss within the inlet duct, thereby increasing backpressure on the connected turbine (i.e., expansion turbine) and reducing the efficiency of a combined cycle power plant including a gas turbine system. Therefore, it is necessary to at least mitigate or prevent the exhaust flow from separating from the inner surface of the inlet duct before reaching the HRSG. Summary of the Invention

[0003] The following summarizes certain embodiments that are comparable in scope to the initially claimed invention. These embodiments are not intended to limit the scope of the claimed invention, but rather, these embodiments are intended only to provide a brief overview of possible forms of the invention. In fact, the present invention may include various forms that may be similar or different from the embodiments set forth below.

[0004] In certain embodiments, a system includes an exhaust diffuser system for a heat recovery steam generator (HRSG). The system includes an inlet portion, a diffuser portion extending axially from the inlet portion, and an outlet portion fluidly coupled to an axially distal end of the diffuser portion, wherein an outlet area of ​​the outlet portion is greater than an inlet area of ​​the inlet portion. The diffuser portion includes a plurality of wall portions, and the plurality of wall portions are incrementally angled relative to an axial area extending from the inlet portion to the outlet portion.

[0005] In certain embodiments, a system includes a gas turbine system, a heat recovery steam generator (HRSG), and an exhaust diffuser system. The exhaust diffuser system includes an inlet portion coupled to the gas turbine system, a diffuser portion extending axially from the inlet portion, and a plenum fluidly coupled to an axially distal end of the diffuser portion, wherein the plenum is coupled to the HRSG, and wherein a plenum area of ​​the plenum is greater than an inlet area of ​​the inlet portion. The diffuser portion includes a plurality of wall portions that are incrementally angled relative to an axial area extending from the inlet portion to the plenum, and the plenum includes a curved wall extending transverse to the axial area.

[0006] In certain embodiments, a method includes receiving an exhaust flow from a gas turbine via an inlet portion of an exhaust diffuser system. The method also includes expanding the exhaust flow in the diffuser portion of the exhaust diffuser system, wherein the diffuser portion includes a plurality of wall portions that are incrementally angled from the inlet portion toward an outlet portion of the exhaust diffuser system. The method also includes discharging the exhaust flow into a HRSG via a plenum of the outlet portion, wherein the plenum includes a curved wall extending across the diffuser portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] These and other features, aspects, and advantages of the present invention will be better understood when the following detailed description is read with reference to the accompanying drawings, in which like characters represent like parts throughout, and in which:

[0008] Figure 1 is a block diagram of one embodiment of a combined cycle power plant system (hereinafter referred to as a "combined cycle system") having a gas turbine system, a steam turbine system, a HRSG, and an exhaust diffuser system located between the gas turbine system and the HRSG.

[0009] Figure 2 is coupled to Figure 1 A side view of an embodiment of an exhaust diffuser system for a HRSG illustrating aspects of the exhaust diffuser system that facilitate transitioning exhaust flow into the HRSG;

[0010] Figure 3 yes Figure 2 a side view of an embodiment of an exhaust diffuser system illustrating aspects of a coupling portion and a transition portion of the exhaust diffuser system;

[0011] Figure 4 yes Figure 2 A top view of an embodiment of an exhaust diffuser system illustrating aspects of a coupling portion and a transition portion of the exhaust diffuser system;

[0012] Figure 5 yes Figure 2 an elevation view of an embodiment of an exhaust diffuser system illustrating aspects of a transition portion of the exhaust diffuser system having a plurality of incrementally angled flat wall portions;

[0013] Figure 6 yes Figure 2 , illustrating aspects of a transition portion of the exhaust diffuser system having a plurality of incrementally angled curved wall portions; and

[0014] Figure 7 Is used for operation Figure 2A flow chart of one embodiment of a method of an inlet portion of an exhaust diffuser system. DETAILED DESCRIPTION

[0015] One or more specific embodiments of the present invention will be described below. In order to provide a concise description of these embodiments, not all features of an actual implementation may be described in the specification. It should be understood that in the development of any such actual implementation, as in any engineering or design project, many implementation-specific decisions must be made to achieve the developer's specific goals, such as complying with system-related and business-related constraints, which may vary from implementation to implementation. Furthermore, it should be understood that such development work may be complex and time-consuming, but remains a routine task of design, fabrication, and manufacturing for those of ordinary skill having the benefit of this disclosure.

[0016] When introducing elements of various embodiments of the present invention, the articles "a," "an," "the," and "said" are intended to mean that there are one or more of the elements. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0017] As described in more detail below, embodiments disclosed herein include an exhaust diffuser system (e.g., an inlet duct) for a HRSG that is configured to mitigate flow separation of the exhaust gas flow from the inner surface of a transition portion of the exhaust diffuser system. In certain embodiments, the exhaust diffuser system includes an inlet portion coupled to the transition portion, the transition portion extending axially from the inlet portion. The transition portion includes a plurality of side walls, wherein one or more side walls have a plurality of wall portions. These wall portions are incrementally angled outwardly so that the transition portion gradually expands outwardly along the axial region of the transition portion. Gradually expanding the transition portion mitigates flow separation of the exhaust gas flowing through the transition portion from the inner surface of the transition portion, thereby mitigating the formation of vortices between the inner surface and the exhaust gas flow.

[0018] In certain embodiments, the transition portion is coupled to the coupling portion. The coupling portion includes a curved wall extending transverse to an axial extent of the transition portion. The transition portion is coupled to a convex side of the curved wall of the coupling portion. Additionally, the transition portion is coupled to a bottom portion of the curved wall of the coupling portion. The coupling portion includes an interface having a first lateral region and a second lateral region. The interface is fluidically coupled to the lateral side of the HRSG, thereby fluidly coupling the inlet portion and the transition portion to the HRSG.

[0019] Figure 11 is a block diagram of an embodiment of a combined cycle system 10 having a gas turbine system 12, a steam turbine system 14, a heat recovery steam generator (HRSG) 16, a gas processing system 18 having one or more gas capture systems 20, and an exhaust diffuser system 22 (e.g., inlet ducting, inlet ducting, etc.). The gas capture system 20 is configured to capture undesirable gases (e.g., CO2) from gases such as exhaust gas and / or air. The exhaust diffuser system 22 includes an inlet portion 23 (e.g., inlet portion), a transition portion 24 (e.g., transition portion, diffuser portion) coupled to the inlet portion 23, and a coupling portion 26 (e.g., outlet portion, plenum), wherein the inlet portion 23 is coupled to the gas turbine system 12 and the coupling portion 26 is coupled to the HRSG 16. The coupling portion 26 is configured to transition the exhaust gas 152 from the transition portion 24 to the HRSG 16.

[0020] Before discussing the details of the gas treatment system 18 and the exhaust diffuser system 22, various aspects of the combined cycle system 10 are discussed in greater detail. For purposes of orientation in the drawings, reference may be made to an axial direction or axis 30, a radial or vertical direction or axis 32 extending radially away from the axial direction or axis 30, and a lateral direction or axis 34 extending away from the axial direction or axis 30 and the radial or vertical direction or axis 32. For example, the directions or axes 30, 32, and 34 may reference an axis of rotation 36 of the gas turbine system 12. Additionally, the directions or axes 30, 32, and 34 may reference a central axis of the exhaust diffuser system 22.

[0021] The gas turbine system 12 may include an air intake section 40, a compressor or compressor section 42, a combustor section 44, a gas (expansion) turbine or turbine section 46, and an exhaust section 48. The compressor section 42 may include at least one shaft 50 disposed along the axis of rotation 36, a casing 52 (e.g., an annular casing) disposed circumferentially about the at least one shaft 50, a plurality of rotating compressor blades 54 extending radially outward from the at least one shaft 50, and a plurality of stationary compressor vanes 56 extending radially inward from the casing 52 toward the at least one shaft 50. In the illustrated embodiment, the compressor section 42 may include a plurality of compressor stages 58, each compressor stage having a plurality of compressor vanes 56 circumferentially spaced about the at least one shaft 50 at axial locations and a plurality of compressor blades 54 circumferentially spaced about the at least one shaft 50 at different axial locations immediately adjacent the axial locations of the compressor vanes 56 (i.e., the compressor vanes 56 and compressor blades 58 are axially spaced). Thus, compressor section 42 is configured to receive a flow of intake gas 60 from intake section 40 and progressively compress the intake gas 60 through a plurality of compressor stages 58. As discussed in greater detail below, intake gas 60 may include intake air, an exhaust gas recirculation (EGR) flow or recirculated exhaust gas, or a combination thereof.

[0022] The combustor section 44 may include one or more combustors 62, such as a single annular combustor disposed circumferentially about the axis of rotation 36 or a plurality of combustors 62 spaced circumferentially about the axis of rotation 36. In the illustrated embodiment, each combustor 62 includes a head end portion 64 coupled to a combustion section 66. In the exemplary arrangement, the combustion section 66 includes a combustion chamber 68, a combustor liner 70 disposed circumferentially about the combustion chamber 68, a flow sleeve 72 disposed circumferentially about the combustor liner 70, and a passage 74 extending between the combustor liner 70 and the flow sleeve 72. The passage 74 is configured to convey a flow of compressed gas in an upstream direction 76 toward a head end plenum 78 disposed in the head end portion 64. The head end plenum 78 of the combustor 62 and the combustion chamber 68 are separated or partitioned from each other by an intermediate plate 80. Within the head end plenum 78, a plurality of fuel nozzles 82 are coupled to the intermediate plate 80 and an end plate 84 of the head end portion 64. In operation, each combustor 62 receives compressed gas 86 (eg, air, EGR, etc.) from the compressor section 42 , routes the compressed gas 86 along passage 74 toward the headend chamber 78 as indicated by arrows 76 , and delivers the compressed gas through fuel nozzles 82 into the combustion chamber 68 .

[0023] In certain embodiments, each burner 62 may receive one or more fuel streams from a fuel system 88 coupled to the fuel nozzles 82, wherein the fuel system 88 includes a fuel supply system 90 coupled to one or more fuel circuits 92. For example, the fuel circuits 92 may include fuel circuits 94, 96, and 98 coupled to different groups of fuel nozzles 82. The fuel circuits 92 (e.g., 94, 96, and 98) may include fuel conduits, fuel manifolds, fuel valves, pressure regulators, and other flow control components. The fuel system 88 is configured to supply one or more fuels, such as liquid fuel and / or gaseous fuel, to each of the fuel nozzles 82 for injection into the combustion chamber 68. The fuel may include natural gas, syngas generated by a gasifier, methane, hydrogen, biofuel, fuel oil, or any combination thereof. The fuel supply system 90 may include multiple components for controlling the flow of various fluids to the burners 62. For example, the fuel supply system 90 may include one or more components 100. In certain embodiments, component 100 may include one or more fuel tanks, fuel pumps, valves, pressure regulators, flow regulators, filters, water removal units, particulate removal units, manifolds, flow controllers, or any combination thereof.

[0024] The fuel nozzles 82 are configured to inject one or more fuels from a fuel system 88 and compressed gas 86 from the compressor section 42. In certain embodiments, the fuel nozzles 82 are configured to inject compressed air 104 from a compressor system 106 having an air compressor 108 coupled to a drive device 110, such as an electric motor, an internal combustion engine, a shaft coupled to the gas turbine system 12, or another suitable drive device. The compressor system 106 can be configured to receive air from the environment and / or from the intake section 40. Additionally, the compressor system 106 can be configured to enable multiple operating modes, such as an EGR mode or a non-EGR mode.

[0025] For example, in certain embodiments of the gas turbine system 12 with exhaust gas recirculation (EGR), the compressor section 42 supplies compressed gas 86 (e.g., compressed exhaust gas) to each combustor 62, while the compressor system 106 supplies compressed air 104 to each combustor 62. By way of further example, in certain embodiments of the gas turbine system 12 without exhaust gas recirculation (EGR), the compressor section 42 supplies compressed gas 86 (e.g., compressed air) to each combustor 62 without an additional air supply. Thus, the compressor system 106 may optionally supply compressed air 104 to each combustor 62. In operation, fuel may be combusted with air in the combustion chamber 68 of each combustor 62, thereby generating hot combustion gases 112 for delivery from the combustion chamber 68 to the turbine section 46.

[0026] The turbine section 46 includes at least one shaft 114 disposed along the axis of rotation 36, a casing 116 (e.g., an annular casing) disposed circumferentially about the at least one shaft 114, a plurality of rotating turbine blades 118 extending radially outward from the at least one shaft 114, and a plurality of stationary turbine guide vanes 120 extending radially inward from the casing 116 toward the at least one shaft 114. The turbine section 46 may include a plurality of turbine stages 122, each having a plurality of turbine guide vanes 120 circumferentially spaced about the at least one shaft 114 at axial positions and a plurality of turbine blades 118 circumferentially spaced about the at least one shaft 114 at different axial positions that are immediately adjacent to the axial positions of the turbine blades 118 (i.e., the turbine guide vanes 120 and the turbine blades 118 are axially spaced). The at least one shaft 114 may also be coupled to the at least one shaft 50 of the compressor section 42 via at least one intermediate shaft 124.

[0027] Additionally, the at least one shaft 114 may be coupled to a load 126 via a shaft 128. In certain embodiments, the load 126 may include a generator, a machine, a propulsion system for a vehicle, or any other suitable load. In the illustrated embodiment, the load 126 may be a generator, such that the combined cycle system 10 is a combined cycle power plant. In operation, combustion gases 112 flow from the combustor 62 into the turbine section 46, where the combustion gases 112 progressively expand and drive rotation of turbine blades 118 in each of the turbine stages 122 that are coupled to the at least one shaft 114. Thus, the combustion gases 112 drive the turbine section 46, which in turn drives the compressor section 42 and the load 126 via the interconnected shafts 50, 124, 114, and 128.

[0028] In certain embodiments, the gas turbine system 12 can be configured to have a common rotational direction for the shafts 50, 114, 124, and 128 and the connected compressor blades 54 and turbine blades 118. The shafts 50, 114, 124, and 128 can be removably coupled together using shaft connectors such as flange joints. In some embodiments, some of these shafts can be combined to reduce the number of shafts. For example, all of the illustrated shafts 50, 114, and 124 can represent common shafts that rotate in a common rotational direction, such as a clockwise or counterclockwise rotational direction.

[0029] The gas turbine system 12 may be configured with or without the compressor system 106 and an exhaust gas recirculation (EGR) system 150. The EGR system 150 is configured to recirculate exhaust gas 152 output by the turbine section 46 back into the compressor section 42 (e.g., via the intake section 40) for compression and delivery to the combustor section 44. However, the gas turbine system 12 may not include the EGR system 150 and simply induct an airflow into the intake section 40 for compression by the compressor section 42.

[0030] In certain embodiments of the gas turbine system 12 having the EGR system 150, the recirculated exhaust gas 152 flows through the intake section 40 and each of the compressor stages 58 of the compressor section 42, thereby compressing the recirculated exhaust gas into compressed gas 86 for delivery to the combustor section 44. Additionally, the combustor section 44 may receive compressed air 104 from the air compressor 108 of the compressor system 106 via the fuel nozzles 82. The combustor section 44 also receives fuel from the fuel system 88, such as via the fuel nozzles 82. The fuel from the fuel system 88 is then combusted with the air from the compressor system 106 to generate combustion gases 112, which then flow through the turbine section 46 to drive the rotation of the turbine blades 118 in each of the turbine stages 122. The recirculated exhaust gas helps to reduce the temperature and certain emissions (e.g., nitrogen oxides (NOx)) associated with combustion in the combustor section 44. X ))'s formation.

[0031] In certain embodiments of the gas turbine system 12 without an EGR system 150, the compressor section 42 receives an air flow from the intake section 40, progressively compresses the air flow via the compressor stages 58, and delivers the compressed air flow as compressed gas 86 to the combustor section 44. The compressed air flow then facilitates combustion of fuel from the fuel system 88, thereby generating hot combustion gases 112 for delivery to the turbine section 46. In such embodiments, the compressor system 106 may not be included, or may be included to provide additional compressed air 104 to the combustor section 44. Regardless of the configuration, the combustion gases 112 drive rotation of turbine blades 118 in the turbine stage 122, thereby rotating at least one shaft 114 coupled to the at least one shaft 50 of the compressor section 42 and a shaft 128 that drives a load 126.

[0032] The exhaust gas 152 output by the turbine section 46 may then pass through the exhaust diffuser system 22 and into the HRSG 16 to transfer heat from the exhaust gas to water to generate steam for the steam turbine system 14. Various aspects of the exhaust diffuser system 22 are discussed in detail below. In the illustrated embodiment, the HRSG 16 may include a high-pressure section 160, an intermediate-pressure section 162, and a low-pressure section 164 arranged in series to generate high-pressure steam 166, intermediate-pressure steam 168, and low-pressure steam 170. The HRSG 16 may include multiple components located in each of the sections 160, 162, and 164, such as economizers, evaporators, superheaters, or any combination thereof. The components of the HRSG 16 may also form tube bundles for each of the sections 160, 162, and 164, such as heat exchanger tube bundles. The components of the HRSG 16 may be coupled together via various ducts and headers. In certain embodiments, components of the HRSG 16 include a final high pressure superheater, a secondary reheater, a primary reheater, a primary high pressure superheater, an interstage attemperator, a high pressure evaporator, a high pressure economizer, an intermediate pressure evaporator, an intermediate pressure economizer, a low pressure evaporator, and a low pressure economizer.

[0033] The heat recovery steam generator 16 can deliver high-pressure steam 166 to a high-pressure steam turbine 172 of the steam turbine system 14, deliver intermediate-pressure steam 168 to an intermediate-pressure steam turbine 174 of the steam turbine system, and deliver low-pressure steam 170 to a low-pressure steam turbine 176 of the steam turbine system. The steam drives the rotation of blades within each of the steam turbines 172, 174, 176, thereby driving a shaft 178 coupled to a load 180, such as an electrical generator. The low-pressure steam turbine 176 can also return condensate 182 to the low-pressure section 164 of the HRSG 16. The HRSG 16 can then output the exhaust gas 152 as partially cooled exhaust gas 184, which can then pass through the gas treatment system 18.

[0034] As discussed above, the gas processing system 18 includes one or more gas capture systems 20. For example, the gas capture system 20 may include any one or any combination of gas capture systems 190, 192, and 194, each having multiple components (e.g., components 196, 198, 200, and 202). The gas capture systems 20 (e.g., 190, 192, and 194) are configured to obtain captured gas 204 from the intake gas 60 and / or the exhaust gas 152, 184. In the illustrated embodiment, the gas capture systems 20 (e.g., 190, 192, and 194) may capture carbon dioxide (CO2) and output it as captured gas 204, which may be further directed to a compression system 206. For example, the compression system 206 may include one or more compressors configured to compress the captured gas 204 (e.g., CO2) and deliver the captured gas to a storage device and / or pipeline 208.

[0035] A gas capture system 190 is disposed at, in, or upstream of the intake section 40 to capture undesirable gases from the intake air. Thus, the gas capture system 190 may be described as a direct air capture (DAC) system. Gas capture systems 192 and 194 are disposed downstream of the gas turbine system 12 and / or the HRSG 16 to capture undesirable gases from the exhaust gases 152 and 184. The gas capture system 20 (e.g., 190, 192, and 194) may include an adsorbent-based gas capture system, a solvent-based gas capture system, a cryogenic gas capture system, or any combination thereof configured to remove and capture undesirable gases.

[0036] In certain embodiments, the gas capture system 20 (eg, 190, 192, and 194) may be configured to remove and capture undesirable gases, such as carbon oxides (CO X ) (e.g., carbon dioxide (CO2) and carbon monoxide (CO)), nitrogen oxides (NO X ) (e.g., nitrogen dioxide (NO2)), sulfur oxides (SO X ) ), or any combination thereof. In the following discussion, the gas capture systems 20 (e.g., 190, 192, and 194) may be described as, for example, adsorbent-based carbon capture systems using adsorbent materials and / or solvent-based carbon capture systems using, for example, liquid absorbents (e.g., solvents). However, the embodiments disclosed herein may use any type or configuration of gas capture systems 20 (e.g., 190, 192, and 194) as noted above.

[0037] Each of the gas capture systems 20 (e.g., 190, 192, and 194) may include components 196, 198, 200, and 202 suitable for supporting the type and configuration of the gas capture system 20, such as components supporting an adsorbent-based gas capture system, a solvent-based gas capture system, a cryogenic gas capture system, or any combination thereof. For example, the components 196, 198, 200, and 202 may include an adsorber with adsorbent material, a solvent-based absorber and stripper, a heat exchanger, a cryogenic system, or any combination thereof. Additionally, one or more components 210, 212, and 214 may be disposed upstream of the gas capture systems 192 and 194, such as a dryer or water removal system (e.g., a moisture separator), a particulate removal system (e.g., a filter and / or a solid-gas separator), one or more booster fans, one or more coolers (e.g., a direct contact cooler (DCC)), or any combination thereof.

[0038] In certain embodiments, the exhaust gas 184 may partially or completely bypass the gas treatment system 18 and flow to the EGR system 150, and / or the exhaust gas 184 may partially or completely flow through the gas treatment system 18 before flowing to the EGR system 150. The EGR system 150 may include one or more conduits, valves, flow controls, coolers, blowers, or any combination thereof configured to provide at least a portion of the exhaust gas 152, 184 (e.g., EGR flow) to the intake section 40 for recirculation through the compressor section 42. The cooler may be configured to cool the exhaust gas 152, 184 to a lower temperature (e.g., approximately ambient temperature) before recirculation into the compressor section 42. The blower may be configured to increase the pressure and flow of the exhaust gas 152, 184 to help overcome pressure losses in the EGR system 150.

[0039] In the illustrated embodiment, the combined cycle system 10 also includes a controller 220 coupled to the gas turbine system 12, the steam turbine system 14, the HRSG 16, the gas processing system 18, the fuel system 88, the EGR system 150, the compression system 106, and various sensors 222 throughout the combined cycle system 10. In the illustrated embodiment, the controller 220 includes one or more processors 224, a memory 226, instructions 228 stored on the memory 226 and executable by the processor 224, and communication circuitry 230 configured to communicate with the sensors 222 and various equipment throughout the combined cycle system 10. For example, the controller 220 is configured to control the delivery and distribution of fuel from the fuel system 88 to the fuel nozzles 82 in the combustor section 44. In certain embodiments, the controller 220 is configured to control the operation of the gas capture system 20 (e.g., 190, 192, and 194), such as by controlling the operating mode (e.g., adsorption mode and desorption mode), controlling the flow of various fluids through the gas capture system 20, or any combination thereof.

[0040] The sensors 222 (labeled "S") are configured to monitor various operating parameters of the combined cycle system 10. In certain embodiments, the sensors 222 include temperature sensors, pressure sensors, flow rate sensors, fluid composition sensors (e.g., gas composition sensors), vibration sensors, clearance sensors, velocity sensors, humidity and / or moisture sensors, or any combination thereof. The sensors 222 may monitor parameters (e.g., temperature, pressure, flow rate, and fluid composition) at one or more locations of the compressor section 42, the combustor section 44, the turbine section 46, the gas processing system 18, or any combination thereof. For example, the sensors 222 may monitor compressor parameters (e.g., the pressure ratio between the inlet and outlet of the compressor section 42), combustion gas parameters (e.g., ignition temperature and combustion dynamics), turbine parameters (e.g., temperature and pressure at each turbine stage, turbine inlet, and turbine exhaust), and exhaust emissions. By further example, the exhaust emissions monitored by the sensors 222 may include carbon oxides (CO X ) such as carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NO X ) such as nitrogen dioxide (NO2), sulfur oxides (SO X ) such as sulfur dioxide (SO ), unburned hydrocarbons, particulate matter, and other undesirable exhaust emissions. By way of further example, sensor 222 may monitor the temperature of the adsorbent material in an adsorbent-based gas capture system, the temperature of the solvent in a solvent-based gas capture system, or any combination thereof. In response to feedback from sensor 222, controller 220 may adjust the operating mode, fluid flow, heating, cooling, or any combination thereof in gas capture system 20.

[0041] As discussed above, the combined cycle system 10 includes the exhaust diffuser system 22 disposed between the gas turbine system 12 and the HRSG 16. Although the transition portion 24 is schematically shown as separate from the gas turbine system 12, the transition portion 24 may be mounted to the gas turbine system 12 at the turbine section 46. For example, the transition portion 24 may be mounted directly or indirectly to an aft frame of the gas turbine system 12 that is coaxial with the axis of rotation of the turbine section 46.

[0042] Figure 2 yes Figure 1 FIG1 is a side view of an embodiment of the HRSG 16, illustrating one embodiment of the exhaust diffuser system 22 of the HRSG 16. In the illustrated embodiment, the HRSG 16 includes sections 160, 162, and 164, although it should be appreciated that the HRSG 16 may include any number of sections. For example, the HRSG 16 may include 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 sections. In the illustrated embodiment, the HRSG 16 is shown extending in the axial direction 30. That is, the sections 160, 162, and 164 of the HRSG 16 are axially positioned in a horizontal orientation.

[0043] As shown, the exhaust diffuser system 22 includes an inlet portion 23, a transition portion 24 (e.g., a diffuser portion, a diffuser duct, a transition portion) extending axially from the inlet portion 23 (e.g., the inlet portion), and a coupling portion 26 (e.g., an outlet portion, a plenum) fluidly coupled to an axially distal end 250 of the transition portion 24. As shown, an outlet area 252 (e.g., an outlet vertical area, a plenum area) of the coupling portion 26 is larger than an inlet area 254 (e.g., an inlet vertical area) of the inlet portion 23.

[0044] In the illustrated embodiment, the coupling portion 26 includes a curved wall 256 extending across an axial region 258 of the exhaust diffuser system 22. For example, the curved wall 256 may have a U-shaped cross-section (e.g., a semicircular cross-section) extending in the radial or vertical direction 32. In certain embodiments, the curved wall 256 may be a semi-cylindrical wall or a frusto-conical wall extending in the radial or vertical direction 32. The curved wall 256 may increase the rigidity or structural support of the coupling portion 26 and the entire exhaust diffuser system 22. The transition portion 24 is coupled to a convex side 260 of the curved wall 256. In the illustrated embodiment, the transition portion 24 is coupled to a bottom portion 261 of the curved wall 256. In certain embodiments, the transition portion 24 may be coupled to a middle portion or a top portion of the curved wall 256.

[0045] In the illustrated embodiment, the exhaust diffuser system 22 is coupled to a lateral side 262 of the HRSG 16 via the coupling portion 26. As shown, an interface 264 formed at a longitudinal distal end 266 of the coupling portion 26 is configured to engage (e.g., intersect) the lateral side 262 of the HRSG 16. That is, the perimeter of the interface 264 is configured to couple to the perimeter of the lateral side 262 of the HRSG 16. In the illustrated embodiment, the concave side 270 of the curved wall 256 is configured to fluidly couple to the HRSG 16 via the engagement between the interface 264 and the lateral side 262 of the coupling portion 26. In other embodiments, the HRSG 16 may extend in the vertical direction 32 (e.g., in a vertical configuration) such that the sections 160, 162, and 164 of the HRSG 16 are vertically stacked. In certain embodiments, the exhaust diffuser system 22 may be coupled to the top or bottom side of the HRSG 16 in a vertical configuration.

[0046] As discussed in greater detail herein, the transition portion 24 includes a plurality of wall portions 272 (e.g., plates) that are incrementally angled relative to an axial region 258 extending from the inlet portion 23 to the coupling portion 26. In certain embodiments, the wall portions 272 can include flat plates, panels, or sheets (e.g., sheet metal) such that the angle of each wall portion 272 is constant along the width of the corresponding wall portion 272, and the wall portions 272 are incrementally angled, with one constant angle followed by another constant angle. In certain embodiments, the wall portions 272 can include curved plates, panels, or sheets (e.g., sheet metal) such that each wall portion 272 has a curvature along directions 30, 32, and / or 34, and the angle of each wall portion 272 can be variable. For example, each wall portion 272 may be slightly curved, wherein the radius is equal to or greater than (e.g., 1 times, 1.1 times, 1.2 times, 1.3 times, 1.5 times, 2 times, or 3 times) the height and / or width of the transition portion 24 at the location of each corresponding wall portion 272.

[0047] In the illustrated embodiment, the continuous wall portions 272 are coupled at the boundary 274. In certain embodiments, the continuous wall portions 272 can be separate plates (e.g., thin sheets) coupled via welding (e.g., welded joints) or multiple mechanical fasteners (e.g., rivets, screws). That is, the boundary 274 can include weld lines and / or overlaps of the continuous wall portions 272. In other embodiments, the multiple wall portions 272 can be formed into a single plate via the plate being bent at the boundary 274. That is, in certain embodiments, the boundary 274 between the continuous wall portions 272 can include bending of the material (e.g., creases and angle changes). It should be recognized that the boundary 274 gives the multiple wall portions 272 a self-reinforcement (e.g., self-strengthening) function. This self-reinforcement function of the boundary 274 can be used in combination with an external support structure, or in certain embodiments, can completely replace the external support structure that would otherwise be required to support the exhaust diffuser system 22.

[0048] In certain embodiments, the transition portion 24 is formed by rolling (e.g., roll-bending) a single wall portion 272 to form a continuously curved shape without discrete (e.g., step-like) changes in angle. In certain embodiments, the transition portion 24 may include a plurality of wall portions 272, wherein at least one of the wall portions 272 has a gradually curved shape formed by rolling. The method of rolling at least one of the wall portions 272 may include feeding the at least one wall portion 272, which may be composed of metal, into a three-roll roll bender.

[0049] Figure 3 yes Figure 2 FIG. 1 is a side view of an embodiment of an exhaust diffuser system 22 illustrating an embodiment of a transition portion 24 of the exhaust diffuser system 22 and an embodiment of a coupling portion 26 of the exhaust diffuser system 22. In the illustrated embodiment, the transition portion 24 includes a side wall 280. In the illustrated embodiment and as shown in FIG. Figure 5 and Figure 6 As more clearly seen in FIG, sidewall 280 includes a first sidewall 281 (e.g., a first lateral side), a second sidewall 282 (e.g., a top side), a third sidewall 284 (e.g., a second lateral side), and a fourth sidewall 286 (e.g., a bottom side). In certain embodiments, transition portion 24 can include fewer or more sides. For example, transition portion 24 can include 3, 5, 6, 7, 8, or more sides.

[0050] In the illustrated embodiment, the first side wall 281, the second side wall 282, and the fourth side wall 286 each include a wall portion 272. In certain embodiments, the third side wall 284 also includes a wall portion 272. As shown, the wall portion 272 includes a plurality of first wall portions 290 (e.g., first wall portions 292, 294, 296, 298, 300, and 302) that form the first side wall 281 of the transition portion 24. The first wall portion 290 includes a first outer surface 304 (e.g., first outer surfaces 306, 308, 310, 312, 314, and 316). Although the illustrated embodiment shows the first side wall 281 having six first wall portions 290, the first side wall 281 may include fewer or more first wall portions 290. For example, the first side wall 281 can include 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, or more first wall portions 290 and corresponding first outer surfaces 304. In certain embodiments, the first side wall 281 can include four or more first wall portions 290. Additionally, any combination of the first wall portions 290 can be equivalent to each other (e.g., of equal size) in a longitudinal area relative to the axial direction 30. However, in some embodiments, the dimensions of the first wall portions 290 along the axial direction 30 can be different.

[0051] In the illustrated embodiment, the wall portion 272 additionally includes second wall portions 318 (e.g., second wall portions 320, 322, 324, 326, 328, and 330) that form the second side wall 282 of the transition portion 24. The second wall portions 318 include second exterior surfaces 332 (e.g., second exterior surfaces 334, 336, 338, 340, 342, and 344). Although the illustrated embodiment shows the second side wall 282 having six second wall portions 318, the second side wall 282 may include fewer or more second wall portions 318. For example, the second side wall 282 may include three, four, five, six, seven, eight, nine, ten, eleven, twelve, fourteen, sixteen, eighteen, twenty, or more second wall portions 318 and corresponding second exterior surfaces 332. In certain embodiments, the second side wall 282 may include four or more second wall portions 318. Additionally, any combination of second wall portions 318 may be equivalent to one another (eg, equally sized) in a longitudinal area relative to the axial direction 30. However, in some embodiments, the dimensions of the second wall portions 318 along the axial direction 30 may not be the same.

[0052] In the illustrated embodiment, the wall portion 272 additionally includes fourth wall portions 346 (e.g., fourth wall portions 348, 350, 352, 354, 356, and 358) that form the fourth side wall 286 of the transition portion 24. The fourth wall portion 346 includes a fourth exterior surface 360 ​​(e.g., fourth exterior surfaces 362, 364, 366, 368, 370, and 372). Although the illustrated embodiment shows the fourth side wall 286 having six fourth wall portions 346, the fourth side wall 286 may include fewer or more fourth wall portions 346. For example, the fourth side wall 286 may include 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, or more fourth wall portions 346 and corresponding fourth exterior surfaces 360. In certain embodiments, the fourth side wall 286 may include four or more fourth wall portions 346. Additionally, any combination of fourth wall portions 346 can be equivalent to one another (e.g., of equal size) in a longitudinal area relative to the axial direction 30. However, in some embodiments, the dimensions of the fourth wall portions 346 along the axial direction 30 may be different. The wall portion 272 can additionally include a third wall portion forming a third side wall 284 and a corresponding third outer surface, which are described in greater detail herein.

[0053] In the illustrated embodiment, the second wall portions 318 of the second side wall 282 are incrementally angled relative to successive second wall portions 318 such that successive second wall portions 318 are angled at second angles 374 (e.g., second angles 375, 376, 378, 380, and 382), each second angle 374 spanning adjacent second outer surfaces 332 of successive second wall portions 318. In certain embodiments, each second angle 374 is between 150 and 179 degrees, between 165 and 178 degrees, or between 168 and 175 degrees. In certain embodiments, any combination of the second angles 374 may be equivalent to one another. In certain embodiments, each successive second wall portion 318 has an angle change relative to the previous second wall portion 318 of less than or equal to 2, 3, 4, 5, 6, 7, 8, 9, or 10 degrees (e.g., 2 to 10 degrees or 3 to 7 degrees) along the direction of exhaust gas flow through the exhaust diffuser system 22, thereby helping to reduce the risk of exhaust gas flow separation along the second side wall 282. In certain embodiments, the second wall portions 318 gradually and stepwise angle upward as the transition portion 24 extends from the inlet portion 23 to the coupling portion 26 along the direction of exhaust gas flow through the exhaust diffuser system 22. Collectively, the upwardly angled second wall portions 318 of the fourth side wall 286 can define an upwardly concave, increasing slope of the second side wall 282.

[0054] In the illustrated embodiment, the fourth wall portion 346 of the fourth side wall 286 is incrementally angled relative to the continuous fourth wall portion 346, such that the continuous fourth wall portion 346 is at a fourth angle 384 (e.g., fourth angles 385, 386, 388, 390, and 392), each fourth angle 384 spanning adjacent fourth exterior surfaces 360 of the continuous fourth wall portion 346. In certain embodiments, each fourth angle 384 is between 150 and 179 degrees, between 165 and 178 degrees, or between 168 and 175 degrees. In certain embodiments, any combination of the fourth angles 384 may be equivalent to each other. Additionally or alternatively, any combination of the fourth angles 384 may be equivalent to any combination of the second angles 374 described herein. In certain embodiments, each successive fourth wall portion 346 varies in angle relative to the previous fourth wall portion 346 by less than or equal to 2, 3, 4, 5, 6, 7, 8, 9, or 10 degrees (e.g., 2 to 10 degrees or 3 to 7 degrees) along the direction of exhaust gas flow through the exhaust diffuser system 22, thereby helping to reduce the risk of exhaust gas flow separation along the fourth side wall 286. In certain embodiments, as the transition portion 24 extends from the inlet portion 23 to the coupling portion 26 along the direction of exhaust gas flow through the exhaust diffuser system 22, the fourth wall portion 346 gradually and stepwise angles upward (e.g., defining an upwardly angled portion of the fourth side wall 286) and then gradually and stepwise angles downward (e.g., defining a downwardly angled portion of the fourth side wall 286). Collectively, the upwardly angled portion and the downwardly angled portion of the fourth side wall 286 can define a downwardly concave geometry of the fourth side wall 286. The upwardly angled portion of fourth side wall 286 is configured to help direct the exhaust flow upward against second side wall 282 , further helping to avoid or reduce the risk of flow separation along second side wall 282 .

[0055] In certain embodiments, the first side wall 281, the third side wall 284, and / or the fourth side wall 286 of the transition portion 24 may comprise a single wall portion that is opposite to a plurality of wall portions. That is, in certain embodiments, the first side wall 281, the third side wall 284, and / or the fourth side wall 286 may not gradually expand and / or may not gradually change via the wall portion. As discussed herein, the incrementally angled wall portion 272 causes the transition portion 24 to gradually expand. This gradual expansion of the angled wall portion 272 reduces the possibility of flow separation from the inner surface of the transition portion 24. In certain embodiments, the gradual expansion of the side wall 280 achieved by gradually angling the wall portion 272 is applied to at least the second (top) side wall 282.

[0056] In the illustrated embodiment, the first wall portion 290 is coupled to the second wall portion 318 to form a plurality of first edges 394 (e.g., first edges 396, 398, 400, 402, 404, and 406) that couple the first side wall 281 of the transition portion 24 to the second side wall 282 of the transition portion 24. That is, the first wall portions 292, 294, 296, 298, 300, and 302 are coupled to the second wall portions 320, 322, 324, 326, 328, and 330 via the first edges 396, 398, 400, 402, 404, and 406, respectively. Additionally, the first wall portion 290 is coupled to the fourth wall portion 346 to form a plurality of fourth edges 408 (e.g., fourth edges 410, 412, 414, 416, 418, and 420) that couple the first side wall 281 of the transition portion 24 to the fourth side wall 286 of the transition portion 24. That is, the first wall portions 292, 294, 296, 298, 300 and 302 are coupled to the fourth wall portions 348, 350, 352, 354, 356 and 358 via the fourth edges 410, 412, 414, 416, 418 and 420, respectively.

[0057] In the illustrated embodiment, transition portion 24 includes an inlet side 422 coupled to inlet portion 23 of exhaust diffuser system 22. Additionally, transition portion 24 includes an outlet side 424 coupled to coupling portion 26 of exhaust diffuser system 22. In the illustrated embodiment, a first area 426 (e.g., vertical area) of outlet side 424 is greater than a second area 428 (e.g., vertical area) of inlet side 422. Additionally, a first central axis 430, which is orthogonal to first area 426, is offset in direction 32 relative to a second central axis 432, which is orthogonal to second area 428. In the illustrated embodiment, first central axis 430 is vertically higher than second central axis 432. That is, first side wall 281 and third side wall 284 are asymmetric about a plane (e.g., a horizontal plane) passing through axis 30 and axis 34. Similarly, second (top) side wall 282 and fourth (bottom) side wall 286 are asymmetric about a plane (e.g., a horizontal plane) passing through axis 30 and axis 34. In certain embodiments, the first central axis 430 can be vertically lower than the second central axis 432 , or in certain embodiments, be at the same vertical height as the second central axis 432 .

[0058] In the illustrated embodiment, the first area 426 of the outlet side 424 of the transition portion 24 is smaller than the outlet area 252 of the coupling portion 26. In certain embodiments, the first area 426 can be smaller than or equal to the outlet area 252. For example, the first area 426 can be less than 10%, 25%, 50%, 75%, or 100% of the outlet area 252. As discussed herein, the first central axis 430 of the first area 426 is offset from the coupling central axis 434 of the coupling portion 26. In the illustrated embodiment, the first central axis 430 is lower than the coupling central axis 434. That is, the outlet side 424 of the transition portion 24 is coupled to the lower portion 436 of the coupling portion 26. In certain embodiments, the first central axis 430 can be aligned with the coupling central axis 434 or, in certain embodiments, be higher than the coupling central axis 434.

[0059] In the illustrated embodiment, the coupling portion 26 includes a curved wall 256 extending transverse to an axial region 258 of the exhaust diffuser system 22. As shown, the transition portion 24 is coupled to a convex side 260 of the curved wall 256. The outlet region 252 of the coupling portion 26 extends transverse to the coupling center axis 434. In the illustrated embodiment, the coupling portion 26 includes a first lateral wall 448 (e.g., a top wall) coupled to the curved wall 256, disposed in a direction 32 away from the coupling center axis 434, and extending transversely from the curved wall 256. The coupling portion 26 also includes a second lateral wall 450 (e.g., a bottom wall) coupled to the curved wall 256, disposed in a direction 452 away from the coupling center axis 434, and extending transversely from the curved wall 256. As shown, the first lateral wall 448 and the second lateral wall 450 are convexly curved relative to the coupling center axis 434.

[0060] In the illustrated embodiment, transition portion 24 includes a diagonal portion 453 including a first diagonal surface 454 adjacent to inlet portion 23 and disposed along first plurality of edges 394. In the illustrated embodiment, first diagonal surface 454 intersects first wall portions 292 and 294 and second wall portions 320 and 322 in a longitudinal direction. In certain embodiments, first diagonal surface 454 may intersect more or fewer first wall portions 290 and / or more or fewer second wall portions 318. Additionally, transition portion 24 includes a fourth diagonal surface 456 adjacent to inlet portion 23 and disposed along fourth plurality of edges 408. In the illustrated embodiment, fourth diagonal surface 456 intersects first wall portions 292 and 294 and fourth wall portions 348 and 350 in a longitudinal direction. In certain embodiments, fourth diagonal surface 456 may intersect more or fewer first wall portions 290 and / or more or fewer fourth wall portions 346.

[0061] Figure 4 yes Figure 2 FIG2 is a top view of an embodiment of the exhaust diffuser system 22, illustrating an embodiment of the transition portion 24 of the exhaust diffuser system 22 and an embodiment of the coupling portion 26 of the exhaust diffuser system 22. In the illustrated embodiment, the wall portion 272 includes a plurality of second wall portions 318 (e.g., second wall portions 320, 322, 324, 326, 328, and 330) that form the second side 282 of the transition portion 24. The second wall portions 318 include second exterior surfaces 332 (e.g., second exterior surfaces 334, 336, 338, 340, 342, and 344). Although the illustrated embodiment shows the second side wall 282 having six second wall portions 318, the second side wall 282 may include fewer or more second wall portions 318. For example, the second side wall 282 can include 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, or more second wall portions 318 and corresponding second exterior surfaces 332. In certain embodiments, the second side wall 282 can include four or more second wall portions 318.

[0062] In the illustrated embodiment, the wall portion 272 includes a plurality of first wall portions 290 (e.g., first wall portions 292, 294, 296, 298, 300, and 302) that form the first side wall 281 of the transition portion 24. The first wall portions 290 include first exterior surfaces 304 (e.g., first exterior surfaces 306, 308, 310, 312, 314, and 316). Although the illustrated embodiment shows the first side wall 281 having six first wall portions 290, the first side wall 281 may include fewer or more first wall portions 290. For example, the first side wall 281 may include 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, or more first wall portions 290 and corresponding first exterior surfaces 304. In certain embodiments, the first side wall 281 may include four or more first wall portions 290. Additionally, any combination of first wall portions 290 may be equivalent to one another (eg, equally sized) in a longitudinal region relative to the axial direction 30. However, in some embodiments, the dimensions of the first wall portions 290 along the axial direction 30 may not be the same.

[0063] In certain embodiments, each successive first wall portion 290 of the first side wall 281 varies in angle relative to the previous first wall portion 290 by less than or equal to 2, 3, 4, 5, 6, 7, 8, 9, or 10 degrees (e.g., 2 to 10 degrees or 3 to 7 degrees) along the direction of exhaust gas flow through the exhaust diffuser system 22, thereby helping to reduce the risk of exhaust gas flow separation along the first side wall 281. In certain embodiments, the first wall portion 290 gradually and stepwise angles outward relative to the central axis (e.g., central axis 434) as the transition portion 24 extends from the inlet portion 23 to the coupling portion 26 along the direction of exhaust gas flow through the exhaust diffuser system 22. Collectively, the outwardly angled first wall portions 290 of the first side wall 281 can define an increasing slope of the first side wall 281 that is concave upward (i.e., away from the central axis 434).

[0064] In the illustrated embodiment, the wall portion 272 includes a plurality of third wall portions 480 (e.g., third wall portions 482, 484, 486, 488, 490, and 492) that form the third side wall 284 of the transition portion 24. The third wall portion 480 includes a third exterior surface 494 (e.g., third exterior surfaces 496, 498, 500, 502, 504, and 506). Although the illustrated embodiment shows the third side wall 284 having six third wall portions 480, the third side wall 284 may include fewer or more third wall portions 480. For example, the third side wall 284 may include 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, or more third wall portions 480 and corresponding third exterior surfaces 494. In certain embodiments, the third side wall 284 may include four or more third wall portions 480. Additionally, any combination of third wall portions 480 may be equivalent to one another (eg, equally sized) in a longitudinal area relative to the axial direction 30. However, in some embodiments, the dimensions of the third wall portions 480 along the axial direction 30 may not be the same.

[0065] In certain embodiments, each successive third wall portion 480 of the third side wall 284 varies in angle relative to the previous third wall portion 480 by less than or equal to 2, 3, 4, 5, 6, 7, 8, 9, or 10 degrees (e.g., 2 to 10 degrees or 3 to 7 degrees) along the direction of exhaust gas flow through the exhaust diffuser system 22, thereby helping to reduce the risk of exhaust gas flow separation along the third side wall 284. In certain embodiments, the third wall portion 480 gradually and stepwise angles outward relative to the central axis (e.g., central axis 434) as the transition portion 24 extends from the inlet portion 23 to the coupling portion 26 along the direction of exhaust gas flow through the exhaust diffuser system 22. Collectively, the outwardly angled third wall portions 480 of the third side wall 284 can define an increasing slope of the third side wall 284 that is concave upward (i.e., away from the central axis 434).

[0066] The first side wall 281, the second side wall 282, the third side wall 284, and the fourth side wall 286 each include the same number of wall portions 272 (i.e., the first wall portion 290, the second wall portion 318, the third wall portion 480, and the fourth wall portion 346). As illustrated in the exemplary embodiment, each side wall 281, 282, 284, 286 includes six wall portions 272, although each side wall may alternatively include 3, 4, 5, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, or more wall portions 272.

[0067] As discussed herein, the first wall portion 290 is coupled to the second wall portion 318 to form a plurality of first edges 394 (e.g., first edges 396, 398, 400, 402, 404, and 406) that couple the first side wall 281 of the transition portion 24 to the second side wall 282 of the transition portion 24. That is, the first wall portions 292, 294, 296, 298, 300, and 302 are coupled to the second wall portions 320, 322, 324, 326, 328, and 330 via the first edges 396, 398, 400, 402, 404, and 406, respectively. In the illustrated embodiment, the second wall portion 318 is coupled to the third wall portion 480 to form a plurality of second edges 508 (e.g., second edges 510, 512, 514, 516, 518, and 520) that couple the second side wall 282 of the transition portion 24 to the third side wall 284 of the transition portion 24. That is, the second wall portions 320, 322, 324, 326, 328, and 330 are coupled to the third wall portions 482, 484, 486, 488, 490, and 492 via the second edges 510, 512, 514, 516, 518, and 520, respectively.

[0068] In the illustrated embodiment, the transition portion 24 includes a diagonal portion 453 including a first diagonal surface 454 adjacent to the inlet portion 23 and disposed along the plurality of first edges 394. As discussed herein, the first diagonal surface 454 intersects the first wall portions 292 and 294 and the second wall portions 320 and 322 in a longitudinal direction. In certain embodiments, the first diagonal surface 454 may intersect more or fewer first wall portions 290 and / or more or fewer second wall portions 318. In the illustrated embodiment, the transition portion 24 includes a second diagonal surface 522 adjacent to the inlet portion 23 and disposed along the plurality of second edges 508. In the illustrated embodiment, the second diagonal surface 522 intersects the second wall portions 320 and 322 and the third wall portions 496 and 498 in a longitudinal direction. In certain embodiments, the second diagonal surface 522 may intersect more or fewer second wall portions 318 and / or more or fewer third wall portions 480.

[0069] As discussed herein, the coupling portion 26 includes a plurality of coupling members extending laterally to the axial region 258 ( Figure 3 ) of the curved wall 256. As shown, the transition portion 24 is coupled to the convex side 260 of the curved wall 256. The second lateral region 524 of the coupling portion 26 extends transverse to the coupling center axis 434 and the first lateral region of the coupling portion 26. In some embodiments, the outlet region 252 of the coupling portion 26 (e.g., Figure 3 ) and the second lateral region 524 may be the same or different from each other. Although see Figure 3 and Figure 4 The outlet area 252 can be larger than the second lateral area 524, but any suitable ratio (e.g., aspect ratio) of the outlet area 252 to the second lateral area 524 of the coupling portion 26 can be used to facilitate interfacing with HRSGs of various shapes and sizes. For example, the outlet area 252 can be smaller than the second lateral area 524. In the illustrated embodiment, the coupling portion 26 includes a first lateral wall 448 coupled to the curved wall 256, disposed in the direction 32 away from the coupling center axis 434, and extending transversely from the curved wall 256.

[0070] In the illustrated embodiment, the curved wall 256 includes curved end portions 526 (e.g., curved end portions 528, 530) disposed at lateral end portions 532 (e.g., lateral end portions 534, 536) of the second lateral region 524. The curved end portions 526 are more sharply curved (e.g., having a smaller radius) than the intermediate portion 538 (e.g., having a larger radius) of the curved wall 256 and transition from the intermediate portion 538 to the intersection 264 (e.g., a lip, an intersection, etc.) disposed at the longitudinal distal end 542 of the coupling portion 26. That is, the curvature associated with the curved wall 256 increases at the curved end portion 526 at the location 544 along the second lateral region 524 of the coupling portion 26. In certain embodiments, location 544 is less than 1%, 2%, 3%, 4%, 5%, 8%, 10%, 15%, or 20% of the total length of the second lateral region 524 distal to the lateral distal end 546 of the second lateral region 524 (e.g., lateral distal ends 548, 550). In certain embodiments, the radius of the intermediate portion 538 of the curved wall 256 may be at least equal to or greater than the second lateral region 524, or in the range of approximately 0.7 to 2 times the second lateral region 524. In certain embodiments, the radius of the intermediate portion 538 may be constant or variable in the vertical direction 32. As described above, the curvature of the curved wall 256 is configured to increase the stiffness and structural support of the exhaust diffuser system 22 while also facilitating expansion of exhaust gases from the transition portion 24 through the coupling portion 26 into the HRSG 16.

[0071] Figure 5 yes Figure 2 FIG2 is a front view of an embodiment of an exhaust diffuser system 22 illustrating an embodiment of a transition portion 24 of the exhaust diffuser system 22 having a plurality of incrementally angled wall portions 272. In the illustrated embodiment, the transition portion 24 includes a first side wall 281, a second side wall 282, a third side wall 284, and a fourth side wall 286, as discussed herein. The transition portion 24 also includes a plurality of first edges 394, a plurality of second edges 508, and a plurality of fourth edges 408, as discussed herein. Additionally, the transition portion 24 includes a plurality of third edges 570 that couple the third wall portion 480 of the third side wall 284 to the fourth wall portion 346 of the fourth side wall 286. In the illustrated embodiment, the transition portion 24 also includes a diagonal portion 453 that includes a first diagonal surface 454, a second diagonal surface 522, and a fourth diagonal surface 456, as discussed herein. Additionally, the diagonal portion 453 includes a third diagonal surface 572 that intersects the plurality of third edges 570 .

[0072] In the illustrated embodiment, the transition portion 24 includes an annular surface 573 that intersects the inlet portion 23. The octagonal outer boundary 574 of the annular surface 573 is formed by the flat portion 576 of the diagonal portion 453 and the first side wall 281, the second side wall 282, the third side wall 284, and the fourth side wall 286. In the illustrated embodiment, the inlet portion 23 extends in the longitudinal direction 30. As shown, the inlet cross-section 578 of the inlet portion 23 is circular in shape. The orifice 580 of the inlet portion 23 is centrally located in the inlet portion 23 and extends through the inner boundary 579 (e.g., inner circular boundary) of the annular surface 573.

[0073] In the illustrated embodiment, each of the plurality of first wall portions 290, the second wall portion 318, and the third wall portion 480 has a flat outer surface. That is, the first outer surface 304, the second outer surface 332, and the third outer surface 494 are flat surfaces (e.g., not curved). In the illustrated embodiment, the fourth outer surface 360 ​​of the fourth wall portion 346 is slightly curved inwardly, so that the fourth outer surface 360 ​​is a concave surface. In the illustrated embodiment, the transition portion 24 includes a plurality of transition cross sections 582. As shown, the plurality of transition cross sections 582 are substantially rectangular, wherein the substantially rectangular shape includes four side walls 280 arranged in a rectangular shape, although the side walls 280 may include some variations (e.g., variations in flatness, angles, etc.). For example, the term "substantially rectangular" may allow for deviations from a straight line along each of the four side walls 280 of up to (or less than) 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10%, where the deviation can be calculated by dividing the maximum height (H) from the straight line by the total length (L) of the straight line along each of the side walls 280 (e.g., deviation = H / L). For another example, the term "substantially rectangular" may allow for deviations from 90 degrees between each pair of adjacent sides of the four side walls 280 of up to (or less than) 1 degree, 2 degrees, 3 degrees, 4 degrees, 5 degrees, 6 degrees, 7 degrees, 8 degrees, 9 degrees, or 10 degrees. In some embodiments, the fourth exterior surface 360 ​​is a flat exterior surface, such that each of the plurality of transition cross sections 582 of the transition portion 24 is rectangular. In some embodiments, at least one of the plurality of first wall portions 290, the second wall portion 318, the third wall portion 480, or the fourth wall portion 346 has a flat exterior surface.

[0074] Figure 6 yes Figure 2FIG2 is a front view of an embodiment of an exhaust diffuser system 22, illustrating an embodiment of a transition portion 24 of the exhaust diffuser system 22 having a plurality of incrementally angled wall portions 272. In the illustrated embodiment, the transition portion 24 includes a first side wall 281, a second side wall 282, a third side wall 284, and a fourth side wall 286, as discussed herein. The transition portion 24 also includes a plurality of first edges 394, a plurality of second edges 508, a plurality of third edges 570, and a plurality of fourth edges 408, as discussed herein.

[0075] In the illustrated embodiment, each of the plurality of first wall portions 290, the second wall portion 318, and the third wall portion 480 has an outer surface that curves outward. That is, each of the first outer surface 304, the second outer surface 332, and the third outer surface 494 curves outward relative to the axial direction 30 (e.g., bends, bows). In certain embodiments, the fourth outer surface 360 ​​also curves outward relative to the axial direction 30. In certain embodiments, at least one of the plurality of first wall portions 290, the second wall portion 318, the third wall portion 480, or the fourth wall portion 346 has a curved outer surface. It should be understood that "curved" can mean any shape that curves outward (e.g., convex outward). For example, the shape of at least one wall portion in the plurality of wall portions 272 can be a truncated cone (e.g., cone), a parabola, or an ellipse. In certain embodiments, the radius of curvature (e.g., outward curvature) of the first wall portion 290, the second wall portion 318, and the third wall portion 480 may be at least equal to or greater than (e.g., 1 times, 1.1 times, 1.2 times, 1.3 times, 1.4 times, 1.5 times, 2 times, 3 times, 4 times, or 5 times) the width in the lateral direction 34 and / or the height in the vertical direction 32 at the axial position of the radius of curvature along the axial direction 30.

[0076] Figure 7 is the inlet piping used to operate the HRSG (i.e. Figure 2 Flowchart of one embodiment of an example method 600 of an exhaust diffuser system (e.g., an exhaust system for a gas turbine) is shown. In block 602 of method 600, an inlet duct receives an exhaust flow (e.g., flue gas) from a gas turbine via an inlet portion of the inlet duct. In block 604 of method 600, the inlet duct expands the exhaust flow in a diffuser portion. An outlet area of ​​the outlet portion of the inlet duct is larger than an inlet area of ​​the inlet portion. The outlet area and the inlet area intersect an axial area between the inlet portion and the outlet portion. The diffuser portion includes a plurality of wall portions. The plurality of wall portions are incrementally angled relative to the axial area. The incrementally angled wall portions are configured to mitigate flow separation of the exhaust flow from an inner surface of the diffuser portion.

[0077] At block 606, the inlet duct discharges the exhaust flow (e.g., flue gas) into the HRSG via a plenum defined by the coupling portion 26 that is fluidly coupled to the diffuser portion. In certain embodiments, the method 600 includes the plenum laterally expanding the exhaust flow via the plenum. The plenum includes a curved wall extending across an axial region between an inlet portion and an outlet portion of the inlet duct. The curved wall also mitigates flow separation of the exhaust flow from the inner surface of the inlet duct prior to entering the HRSG.

[0078] The technical effects of the embodiments disclosed herein include mitigating flow separation in the exhaust gas flow arriving at the HRSG (i.e., the exhaust diffuser system) in the inlet duct. The inlet duct in the embodiments disclosed herein includes a diffuser portion having a plurality of incrementally angled wall portions. The incrementally angled (e.g., gradually angled) wall portions are configured to mitigate flow separation between the exhaust gas flow (e.g., flue gas) and the inner surface of the inlet duct. Reducing flow separation allows a larger portion of the exhaust gas flow to remain near the inner surface, thereby reducing pressure losses within the inlet duct. Additionally, reducing flow separation reduces turbulence / recirculation, thereby increasing the cross-sectional area available for flow to pass from the inlet to the HRSG. The larger cross-sectional area results in a lower average cross-sectional velocity, which further mitigates flow separation and reduces pressure losses. The reduced pressure losses result in faster static pressure recovery, which promotes higher gas turbine output while maintaining uniform heat exchanger flow. Additionally, the curved shape of the coupling duct coupling the inlet duct to the HRSG smoothly directs the exhaust gas flow to the heat exchanger, thereby reducing turbulence in the exhaust gas flow. Furthermore, the incrementally angled wall sections provide additional mechanical strength to the inlet duct. Specifically, the curved portions (e.g., edges, welds, etc.) where the incrementally angled wall sections meet provide additional reinforcement. This additional reinforcement reduces the cost of constructing the external structure that prevents vibration of the inlet duct panel due to overpressure.

[0079] As set forth below, the subject matter described above in detail can be defined by one or more clauses.

[0080] A system (10) includes an exhaust diffuser system (22) for a heat recovery steam generator (HRSG) (16). The system (10) includes an inlet portion (23), a diffuser portion (24) extending axially from the inlet portion (23), and an outlet portion (26) fluidly coupled to an axially distal end of the diffuser portion (24), wherein an outlet area (252) of the outlet portion (26) is greater than an inlet area (254) of the inlet portion (23). The diffuser portion (24) includes a plurality of wall portions (272), and the plurality of wall portions (272) are incrementally angled relative to an axial area (258) extending from the inlet portion (23) to the outlet portion (26).

[0081] The system (10) of the preceding clause, wherein the diffuser portion (24) comprises a first side (281), a second side (282), a third side (284), a fourth side (286), or a combination thereof, the first side comprising a plurality of first wall portions (290) among the plurality of wall portions (272), the second side comprising a plurality of second wall portions (318) among the plurality of wall portions (272), the third side comprising a plurality of third wall portions (480) among the plurality of wall portions (272), and the fourth side comprising a plurality of fourth wall portions (346) among the plurality of wall portions (272).

[0082] A system (10) according to any of the preceding clauses, wherein the plurality of first wall portions (290) comprises four or more wall portions, the plurality of second wall portions (318) comprises four or more wall portions, the plurality of third wall portions (480) comprises four or more wall portions, the plurality of fourth wall portions (346) comprises four or more wall portions, or a combination thereof.

[0083] A system (10) according to any preceding clause, wherein at least one of the plurality of first wall portions (290), the plurality of second wall portions (318), the plurality of third wall portions (480) and the plurality of fourth wall portions (346) comprises a flat wall portion.

[0084] A system (10) according to any of the preceding clauses, wherein at least one of the plurality of first wall portions (290), the plurality of second wall portions (318), the plurality of third wall portions (480), and the plurality of fourth wall portions (346) includes a wall portion that curves outwardly relative to the axial region (258).

[0085] A system (10) according to any preceding clause, wherein the diffuser portion (24) comprises a plurality of generally rectangular cross-sections formed by a plurality of first wall portions (290), a plurality of second wall portions (318), a plurality of third wall portions (480) and a plurality of fourth wall portions (346).

[0086] The system (10) of any preceding clause, wherein the diffuser portion (24) comprises an annular surface (573) configured to interface with the inlet portion (23), wherein an outer boundary (574) of the annular surface (573) is octagonal in shape.

[0087] A system (10) according to any preceding clause, wherein the angle (374, 384) of adjacent outer surfaces (232, 360) of consecutive wall portions (318, 346) across a plurality of wall portions (272) defining opposing side walls (282, 286) of the diffuser portion (24) is between 165 degrees and 178 degrees.

[0088] The system (10) of any preceding clause, wherein the plurality of wall portions (272) includes at least one wall portion having a frusto-conical shape.

[0089] The system (10) of any preceding clause, wherein the outlet portion (26) comprises a curved wall (256) extending transverse to the axial region (258).

[0090] The system (10) of any preceding clause, wherein the diffuser portion (24) is coupled to a convex side (260) of a curved wall (256) of the plenum (26).

[0091] A system (10) according to any preceding clause, wherein the curvature associated with the curved wall (256) begins to increase at a location (544) along the lateral region (524) of the boost chamber (26), wherein the location (544) is less than 10% of the total length of the lateral region (524) away from the lateral distal end (546) of the boost chamber (26).

[0092] A system (10) as described in any preceding clause, wherein the lateral walls (448, 450) of the boost chamber are coupled to the curved wall (256) and extend across the curved wall (256), wherein the lateral walls (448, 450) are convexly curved relative to the central axis (434) of the boost chamber (26).

[0093] A system (10) as described in any of the preceding clauses, wherein the interface perimeter of the interface (264) of the boost chamber (26) is configured to align with and couple to the side perimeter of the side surface (262) of the HRSG (16), and the concave side (270) of the curved wall (256) is configured to be fluidly coupled to the HRSG (16).

[0094] The system (10) of any preceding clause, comprising a HRSG (16) coupled to a plenum (26) and a gas turbine system (12) coupled to an inlet section (23).

[0095] A system (10) includes a gas turbine system (12), a heat recovery steam generator (HRSG) (16), and an exhaust diffuser system (22). The exhaust diffuser system (22) includes an inlet portion (23) coupled to the gas turbine system (12), a diffuser portion (24) extending axially from the inlet portion (23), and a plenum (26) fluidly coupled to an axially distal end of the diffuser portion (24), wherein the plenum (26) is coupled to the HRSG (16), and wherein a plenum area (252) of the plenum (26) is larger than an inlet area (254) of the inlet portion (23). The diffuser portion (24) includes a plurality of wall portions (272, 290, 318, 480, 346) that are incrementally angled relative to an axial region (258) extending from the inlet portion (23) to the plenum (26), and the plenum (26) includes a curved wall (256) extending transverse to the axial region (258).

[0096] The system (10) of the preceding clause, wherein the diffuser portion (24) is coupled to a convex side (260) of the curved wall (256) of the plenum (26).

[0097] A system (10) according to any preceding clause, wherein the angle (374, 384) of the continuous outer surface (232, 360) of the continuous wall portion (318, 346) across a plurality of wall portions (272) defining opposing side walls (282, 286) of the diffuser portion (24) is between 165 degrees and 178 degrees.

[0098] A method (600) includes receiving (602) an exhaust flow (i.e., flue gas) from a gas turbine system (12) via an inlet portion (23) of an exhaust diffuser system (22). The method (600) also includes expanding (604) the exhaust flow in a diffuser portion (24) of the exhaust diffuser system (22), wherein the diffuser portion (24) includes a plurality of wall portions (272) that are incrementally angled from the inlet portion (23) toward an outlet portion (26) of the exhaust diffuser system (220). The method (600) also includes discharging (606) the exhaust flow into a HRSG (16) via a plenum of the outlet portion (26), wherein the plenum includes a curved wall (256) that extends across the diffuser portion (24).

[0099] The method (600) of the preceding clause, wherein the angle of the continuous outer surface (232, 360) of the continuous wall portion (318, 346) across a plurality of wall portions (272) defining opposing side walls (282, 286) of the diffuser portion (24) is between 165 degrees and 178 degrees.

[0100] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. Such other examples are intended to be 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 with insubstantial differences from the literal language of the claims.

Claims

1. A system (10), comprising: An exhaust diffuser system (22) for a heat recovery steam generator (HRSG) (16) comprising: entrance portion (23); a diffuser portion (24) extending axially from the inlet portion (23), wherein the diffuser portion (24) includes a plurality of side faces (280) arranged about a central axis of the diffuser portion (24); and an outlet portion (26) fluidly coupled to an axially distal end of the diffuser portion (24); wherein an outlet area (252) of the outlet portion (26) is larger than an inlet area (254) of the inlet portion (23), and at least one of the plurality of side surfaces (280) of the diffuser portion (24) includes a plurality of wall portions (272). and the plurality of wall portions (272) are incrementally angled relative to an axial region (258) extending from the inlet portion (23) to the outlet portion (26); wherein each wall portion of the plurality of wall portions (272) is angled relative to a previous wall portion of the plurality of wall portions (272), the angle being within a common angular range of angles between 150 degrees and 179 degrees, or the angle variation between successive wall portions of the plurality of wall portions (272) is less than 10 degrees, or a combination thereof.

2. The system (10) according to claim 1, wherein The plurality of sides (280) of the diffuser portion (24) include: a first side wall (281) comprising a plurality of first wall portions (290) of the plurality of wall portions (272); a second side wall (282) comprising a plurality of second wall portions (318) of the plurality of wall portions (272); a third side wall (284) comprising a plurality of third wall portions (480) of the plurality of wall portions (272); a fourth side wall (286) comprising a plurality of fourth wall portions (346) of the plurality of wall portions (272); Or a combination of these.

3. The system (10) according to claim 2, wherein: The plurality of first wall portions (290) include four or more wall portions, the plurality of second wall portions (318) include four or more wall portions, the plurality of third wall portions (480) include four or more wall portions, the plurality of fourth wall portions (346) include four or more wall portions, or a combination thereof.

4. The system (10) according to claim 2 or 3, wherein: At least one of the plurality of first wall portions (290), the plurality of second wall portions (318), the plurality of third wall portions (480), or the plurality of fourth wall portions (346) includes a flat wall portion.

5. The system (10) according to claim 2, 3 or 4, wherein: At least one of the plurality of first wall portions (290), the plurality of second wall portions (318), the plurality of third wall portions (480), or the plurality of fourth wall portions (346) includes a wall portion that curves outwardly relative to the axial region (258).

6. The system (10) according to claim 2, 3, 4 or 5, wherein: The diffuser portion (24) includes a plurality of generally rectangular cross-sections formed by the plurality of first wall portions (290), the plurality of second wall portions (318), the plurality of third wall portions (480), and the plurality of fourth wall portions (346).

7. The system (10) of claim 1, wherein: The plurality of wall portions (272) includes at least one wall portion having a frusto-conical shape.

8. The system (10) of claim 1, wherein: The outlet portion (26) includes a curved wall (256) extending transverse to the axial region (258).

9. The system (10) according to claim 8, wherein The diffuser portion (24) is coupled to a convex side (260) of the curved wall (256) of the outlet portion (26).

10. The system (10) according to claim 8 or 9, wherein The curvature associated with the curved wall (256) begins to increase at a position (544) along the lateral region (524) of the outlet portion (26), wherein the position (544) is less than 10% of the total length of the lateral region (524) away from the lateral distal end (546) of the outlet portion (26).

11. The system (10) according to claim 8, 9 or 10, wherein: The lateral walls (448, 450) of the outlet portion (26) are coupled to and extend transversely from the curved wall (256), wherein the lateral walls (448, 450) are convexly curved relative to the central axis (434) of the outlet portion (26).

12. The system (10) according to claim 8, 9 or 10, wherein The intersection perimeter of the intersection (264) of the outlet portion (26) is configured to align with and couple to the side perimeter of the side surface (262) of the HRSG (16), and the concave side (270) of the curved wall (256) is configured to fluidly couple to the HRSG (16).

13. A system (10), comprising: Gas turbine system (12); Heat recovery steam generator (HRSG) (16); and The exhaust diffuser system (22) according to any one of claims 1 to 12, wherein the gas turbine system (12) is coupled to the inlet portion (23) of the exhaust diffuser system (22) and the HRSG (16) is coupled to the outlet portion (26) of the exhaust diffuser system (22).

14. A method (600), comprising: receiving (602) an exhaust flow from a gas turbine system (12) via an inlet portion (23) of an exhaust diffuser system (22); causing the exhaust flow to expand (604) in a diffuser portion (24) of the exhaust diffuser system (22), wherein the diffuser portion (24) includes a plurality of sides (280) arranged about a central axis (434) of the diffuser portion (24), at least one of the plurality of sides (280) of the diffuser portion (24) including a plurality of wall portions (272) that are incrementally angled from the inlet portion (23) toward an outlet portion (26) of the exhaust diffuser system (22); and The exhaust gas flow is discharged (606) into a heat recovery steam generator (16) via a plenum of the outlet portion (26), wherein the plenum includes a curved wall (256) extending across the diffuser portion (24).

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