HEAT EXCHANGER HAVING INTERNAL SENSOR GRID AND CONSTRAINTS FOR SENSOR WIRE AND HEAT EXCHANGE TUBES - Patent application

Abstract

To provide a heat exchanger including a sensor grid with sensor leads extending through openings in tube restraints for heat exchange tubes in the heat exchanger.SOLUTION: A heat exchanger includes sensor leads 184 extending through tube restraints 190 for heat exchange tubes 146 in the heat exchanger. The tube restraints 190 include a body 192 having a plurality of tube openings 194 defined therein, each tube opening 194 receiving one heat exchange tube of the set of heat exchange tubes 146 therethrough. The body 192 also includes a sensor lead opening 200 defined therein to receive a sensor lead 184 therethrough. The sensor grid is installed during manufacture rather than in the field, allowing the sensor grid to be on outermost and inner sets of heat exchange tubes in the heat exchanger.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates generally to heat exchangers, and more particularly to a heat exchanger including a sensor grid having sensor leads extending through openings in tube restraints for heat exchange tubes within the heat exchanger, the sensor grid being installed during manufacturing rather than in the field, allowing the sensor grid to be on the outermost and innermost sets of heat exchange tubes within the heat exchanger. [Background technology]

[0002] A convective heat exchanger includes multiple rows of heat exchange tubes in close proximity to one another. While applicable to any heat exchanger, to illustrate the challenges and advantages of embodiments of the present disclosure, the present disclosure considers a heat exchanger in the form of a heat recovery steam generator (HRSG) in a combined cycle power plant (CCPP) including a gas turbine (GT) system and a steam turbine (ST) system. In this setting, the efficiency of the HRSG varies with several operating parameters. In the example of a CCPP, heat input may vary with operating parameters such as, but not limited to, GT system load, ambient temperature, GT system degradation, GT system modifications / upgrades, duct burner load, and deviations between expected and actual operation. Similarly, the heat exchange efficiency within the HRSG may vary with operating parameters of the HRSG, such as its cleanliness.

[0003] Managing the operation of CCPPs and heat exchangers to achieve high-efficiency performance requires the use of sensors within the heat exchangers to measure various operating parameters of the heat exchange process, including, but not limited to, temperature, pressure, and flow rate. Current practice is to attach a sensor grid to the outermost row of heat exchange tubes on the HRSG in situ, i.e., after the HRSG is assembled at the site where it will be used. Each sensor has sensor leads extending from it. Manual installation of the sensors and routing of the sensor leads through (and out of) the HRSG typically requires the use of scaffolding or other high-lift equipment next to the heat exchange tubes, which may be 10 to 25 meters high. Because it is nearly impossible to reach within the rows of heat exchange tubes once assembled, sensors are only attached to the outermost rows of the heat exchanger. As a result, measurements of the operating characteristics of the heat exchange process within the inner rows of heat exchange tubes are unavailable, limiting understanding of how to optimally control the operation of the CCPP or heat exchanger, which affects the heat exchange process and the overall efficiency of the system. Summary of the Invention

[0004] One aspect of the present disclosure provides a heat exchanger including: a plurality of sets of heat exchange tubes arranged adjacent to one another, each set of heat exchange tubes fluidly coupled to at least one end of a header; a sensor grid arranged between the plurality of sets of heat exchange tubes, the sensor grid including a plurality of sensors, each sensor including a sensor lead extending therefrom; and a tube restraint for positioning at least one of the plurality of sets of heat exchange tubes relative to an enclosure, the tube restraint including a tube opening for each of the heat exchange tubes of the respective set of heat exchange tubes and a sensor lead opening, and at least one sensor lead of the sensor grid extends through the sensor lead opening.

[0005] Another aspect of the present disclosure provides a combined cycle power plant (CCPP), the combined cycle power plant including: a gas turbine system; a steam turbine system; and a heat recovery steam generator (HRSG) coupled to the gas turbine system to generate steam for the steam turbine system using exhaust from the gas turbine system, the HRSG including: an enclosure configured to direct the exhaust gas therethrough; a plurality of sets of heat exchange tubes arranged adjacent to one another within the enclosure, each set of heat exchange tubes fluidly coupled to at least one end of a header; a sensor grid arranged between the plurality of sets of heat exchange tubes, the sensor grid including a plurality of sensors, each sensor including a sensor lead extending therefrom; and a tube restraint for positioning at least one of the plurality of sets of heat exchange tubes relative to the enclosure, the tube restraint including a tube opening for each of the heat exchange tubes of a respective set of heat exchange tubes and a sensor lead opening, and at least one sensor lead of the sensor grid extends through the sensor lead opening.

[0006] Another aspect of the present disclosure provides a tube restraint for a set of heat exchange tubes of a heat exchanger, the tube restraint including: a body; a plurality of tube openings defined in the body, each configured to receive one heat exchange tube of the set of heat exchange tubes therethrough; and a sensor lead opening defined in the body and configured to receive a sensor lead therethrough, each tube opening having a dimension larger than the sensor lead opening.

[0007] The exemplary aspects of the present disclosure are designed to solve the problems described herein and / or other problems not discussed.

[0008] These and other features of the present disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure, taken in conjunction with the accompanying drawings which illustrate various embodiments of the present disclosure. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram of an exemplary application in the form of a combined cycle power plant for a heat exchanger according to an embodiment of the present disclosure. [Figure 2] FIG. 1 is a partially transparent perspective view of a heat exchanger with vertical heat exchange tubes according to one embodiment of the present disclosure. [Figure 3] FIG. 1 is a partially transparent perspective view of a heat exchanger with horizontal heat exchange tubes according to one embodiment of the present disclosure. [Figure 4] 1 is a perspective view of an exemplary prior art heat exchange tube. [Figure 5] FIG. 1 is a perspective view of multiple sets of heat exchange tubes and a sensor grid for a heat exchanger according to an embodiment of the present disclosure. [Figure 6] FIG. 1 is a side view of a pair of heat exchange tubes and a sensor grid for a heat exchanger according to an embodiment of the present disclosure. [Figure 7] FIG. 10 is an enlarged side view of a set of heat exchange tubes and a sensor grid for a heat exchanger according to an embodiment of the present disclosure. [Figure 8] FIG. 1 is a perspective view of a tube restraint according to an embodiment of the present disclosure. [Figure 9] FIG. 10 is a perspective view of a conduit passing through a baffle at the end of a header of a heat exchanger according to an embodiment of the present disclosure. [Figure 10] FIG. 10 is an end view of the end of a header having a conduit through a baffle according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] It should be noted that the drawings of the present disclosure are not necessarily to scale. The drawings are intended to depict only typical aspects of the present disclosure and therefore should not be considered limiting of the scope of the present disclosure. In the drawings, like numbers represent like elements between the drawings.

[0011] As an initial issue, a clear explanation of the current state of the art requires the selection of specific terminology when referring to and describing components in an exemplary application in the form of a combined cycle power plant and its components. Wherever possible, common industry terminology is used and utilized consistent with its accepted meaning. Unless otherwise noted, such terminology should be given a broad interpretation consistent with the context of this application and the scope of the appended claims. Those skilled in the art will recognize that in many cases, a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single component may include and be referred to in other contexts as consisting of multiple components. Alternatively, what may be described herein as comprising multiple components may be referred to elsewhere as a single component.

[0012] Additionally, several descriptive terms may be used regularly herein, and it will prove useful to define these terms at the beginning of this section. These terms and their definitions are as follows, unless otherwise stated: As used herein, "downstream" and "upstream" are terms that indicate a direction relative to the flow of a fluid, such as a working fluid, through a turbine engine, or, for example, the flow of hot gases through a heat exchanger. The term "downstream" corresponds to the direction of fluid flow, and the term "upstream" refers to the direction opposite to the flow (i.e., the direction in which the flow occurs). The terms "forward" and "aft," unless otherwise specified, refer to directions, with "forward" referring to the front or compressor end of the engine and "aft" referring to the rear or turbine end of the engine.

[0013] It is often desired to describe components located at different radial positions relative to the central axis. The term "radial" refers to movement or position perpendicular to the axis. In such cases, if a first component is located closer to the axis than a second component, the first component is referred to herein as being "radially inward" or "inside" the second component. Conversely, if a first component is located farther from the axis than the second component, the first component may be referred to herein as being "radially outward" or "outside" the second component. The term "axial" refers to movement or position parallel to the axis. Finally, the term "circumferential" refers to movement or position around the axis. It will be understood that such terms may be applied relative to the central axis of the turbine.

[0014] Additionally, as described below, certain descriptive terms may be used regularly herein: the terms "first," "second," and "third" may be used interchangeably to distinguish one component from another, and are not intended to denote the location or importance of the individual components.

[0015] The terminology used herein is merely for the purpose of describing particular embodiments and is not intended to limit the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural unless expressly stated otherwise. It will be further understood that the terms "comprise" and / or "comprising," as used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or sets thereof. "Optional" or "optionally" means that a subsequently-stated event or circumstance may or may not occur, or that a subsequently-stated component or feature may or may not be present, and that the description includes instances in which the event occurs or the component is present as well as instances in which it does not occur or is not present.

[0016] When an element or layer is referred to as "on," "engaged," "connected," or "coupled" to another element or layer, it can be directly on, engaged, connected, or coupled to the other element or layer, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly engaged," "directly connected," or "directly coupled" to another element or layer, there may not be intervening elements or layers. Other terms used to describe relationships between elements should be interpreted similarly (e.g., "between" versus "directly between," "adjacent to" versus "directly adjacent to," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0017] As described above, the present disclosure provides a heat exchanger including a sensor grid having sensor leads extending through a tube restraint for heat exchange tubes within the heat exchanger. The heat exchanger includes a plurality of sets, e.g., rows, of heat exchange tubes arranged adjacent to one another. The tube restraint includes a body having a plurality of tube openings defined therein, each tube opening receiving one of the sets of heat exchange tubes therethrough. The body also includes a sensor lead opening defined therein for receiving a sensor lead therethrough. Each tube opening has a dimension larger than the sensor lead opening.

[0018] The sensor grid includes multiple sensors that are installed during manufacturing rather than in the field. In this manner, the sensor leads for the sensor grid can be installed through the tube restraint rather than over it. Because each set of heat exchange tubes is accessible during manufacturing as opposed to a field installation location, the sensor grid can be attached to any of the inner sets of heat exchange tubes within the heat exchanger, as well as the outermost set of heat exchange tubes. With the sensor grid positioned in this manner, more data can be collected and used regarding the operation of the heat exchanger to provide more efficient operation of the heat exchanger or power plant in which it is used.

[0019] Referring to FIG. 1 , a heat exchanger according to an embodiment of the present disclosure will be described in connection with an exemplary application in the form of a combined cycle power plant (CCPP) 100. FIG. 1 shows a schematic diagram of the CCPP 100. It is emphasized that the teachings of the present disclosure are applicable to any heat exchanger. The CCPP 100 may include a gas turbine (GT) system 102 operably connected to a generator 104 and a steam turbine (ST) system 110 operably coupled to another generator 112. The generator 104 and the GT system 102 may be mechanically coupled by a shaft 106, which may transfer energy between a drive shaft (not shown) of the GT system 102 and the generator 104.

[0020] It is understood that the generators 104, 112 and shaft 106 may be of any size or type known in the art and may vary depending on their application or the system to which they are connected. The common reference numbers for the generators and shafts are for clarity and do not necessarily imply that the generators or shafts are identical. In the exemplary application, the CCPP 100 is a single shaft system with two generators, however, one skilled in the art will readily understand that the teachings of the present disclosure are applicable to any of a variety of combined cycle power generation systems.

[0021] 1, the heat exchanger 108 is operably connected to the GT system 102 and the ST system 110. As described in more detail herein, the heat exchanger 108 may include a heat recovery steam generator (HRSG) (labeled in the drawings) that includes a sensor grid arranged in accordance with an embodiment of the present disclosure. The heat exchanger 108 may be fluidly connected to both the GT system 102 and the ST system 110 via conventional conduits (numbering omitted).

[0022] The GT system 102 may include a compressor 120 and a combustor 124. The combustor 124 includes a combustion section 126 and a fuel nozzle assembly 128. The GT system 102 also includes a gas turbine 130 coupled to a common compressor / turbine shaft 106. In one non-limiting example, the GT system 102 may be a 7HA.03 engine commercially available from General Electric Company of Greenville, South Carolina. The present disclosure is not limited to any particular GT system and may be implemented in connection with other engines, including, for example, other General Electric HA, F, B, LM, GT, TM, and E-Class engine models, as well as engine models from other manufacturers.

[0023] In operation, air enters the inlet of the compressor 120, is compressed, and discharged to the combustor 124, where a gaseous or liquid fuel, such as natural gas or oil, is burned to provide high-energy combustion gases that drive the gas turbine 130. In the gas turbine 130, the energy of the hot gases is converted into work, some of which is used to drive the compressor 120 through the rotating shaft 106, and the remainder is available for useful work to drive a load, such as the generator 104, via the shaft 106 to generate electricity.

[0024] 1 also represents the CCPP 100 in its simplest form, where the energy in the exhaust gases leaving the gas turbine 130 is converted into additional useful work. The exhaust gases enter a heat exchanger 108 in the form of a HRSG, where water is converted into steam in the manner of a boiler. The heat exchanger 108 can also use the energy to produce high-temperature feedwater.

[0025] The ST system 110 may include one or more steam turbines. For example, the ST system 110 may include a high-pressure (HP) turbine 132, an intermediate-pressure (IP) turbine 134, and a low-pressure (LP) turbine 136, each of which is coupled to the shaft 106. Each steam turbine 132, 134, 136 includes a plurality of rotating blades (not shown) mechanically coupled to the shaft 106. During operation, steam from the heat exchanger 108, and often from other sources, enters the inlet of the HP turbine 132, the IP turbine 134, and / or the LP turbine 136 and is directed to impart power to the blades, rotating the shaft 106. As will be appreciated, steam from an upstream turbine can later be used in a downstream turbine. In this manner, the steam generated by the heat exchanger 108 drives at least a portion of the ST system 110, and additional work is extracted to drive the shaft 106, which in turn generates additional power for an additional load, such as a second generator 112. In some configurations, the turbines 130, 132, 134, 136 drive a common generator.

[0026] 1 also shows a CCPP control system 138 operably coupled to the GT system 102, the heat exchanger (i.e., HRSG) 108, and the ST system 110. The control system 138 may include any now known or later developed computerized controller for providing automated control of the CCPP 100. As described below, the control system 138 may receive data from several sensors of a sensor grid within the heat exchanger 108 and may use the data to control the heat exchanger 108 and / or other portions of the CCPP 100.

[0027] 2 and 3 show partially transparent perspective views of an embodiment of heat exchanger 108. Heat exchanger 108 is shown as an HRSG coupled to GT system 102 (FIG. 1) and configured to deliver steam, for example, to ST system 110 (FIG. 1) and / or heated water to other portions of CCPP 100 (FIG. 1). As shown, heat exchanger 108 houses an insulated enclosure 140 (hereinafter, "enclosure 140") configured to contain fluid 142. Enclosure 140 may be housed within a heat exchanger enclosure 148. Enclosure 140 may house any now known or later developed insulated duct configured to contain fluid 142, for example, with a carbon steel or stainless steel inner liner, an insulating layer, and an outer carbon steel layer. Heat exchanger enclosure 148 may include any now known or later developed structural protection, for example, a building or other physical protection.

[0028] Fluid 142 may be any form of gas having a heat differential with fluid 144 (indicated only by arrows) passing through a plurality of heat exchange tubes 146 of heat exchanger 108. Heat is exchanged between fluid 142 and fluid 144. Fluid 142 may be combustion gas exhaust from GT system 102 (FIG. 1), and fluid 144 may be a liquid (e.g., water) and / or gas (e.g., steam). Fluid 142 passes over and around the exterior surfaces of the plurality of heat exchange tubes 146 and exits enclosure 140 via an exhaust system 150, such as a stack and / or a scrubber, while fluid 144 passes through the interior of the plurality of heat exchange tubes 146.

[0029] 2 and 3 differ in that in FIG. 2, the tubes 146 extend in a vertical direction or vertical configuration with the fluid 142 passing therearound in a generally horizontal direction, whereas in FIG. 3, the tubes 146 extend in a horizontal direction or horizontal configuration with the fluid 142 passing therearound in a generally vertical direction. As used herein, "generally" as applied to the flow direction of the fluid 142 indicates that the fluid will typically proceed in the specified direction with slight or temporary deviations as it passes over or around the tubes 146 that may obstruct its path. While the teachings of the present disclosure will be described with respect to the embodiment of FIG. 2, it will be readily understood that the teachings are equally applicable to the embodiment of FIG. 3.

[0030] The tubes 146 may have the form of any now known or later developed heat exchange tube and may be made of any material capable of providing the desired heat transfer characteristics, flexibility, and ability to withstand the environment to which it is exposed. The tubes 146 may vary in size depending on the application, for example, in some applications the outer diameter may vary from 1.25 inches to 2.0 inches.

[0031] FIG. 4 shows a perspective view of one exemplary prior art heat exchange tube in the form of a finned tube. As shown, in one non-limiting example, a tube 146 may include multiple disks 152 arranged around a central tube 154 aligned longitudinally 156. Each disk 152 may be substantially planar and may be stacked so that it is longitudinally disposed above and / or below at least one adjacent disk 152. The central tube 154 may include any now known or later developed tubular member configured to allow a fluid 144 to pass therethrough, for example, by pumping or other force. Each disk 152 may include multiple fin segments 158 extending radially outward from a disk center portion 160, such that the fin segments 158 extend outward from the center tube 154. The disk center portion 160 extends circumferentially around the outer periphery of the central tube 154. Each of the fin segments 158 is separated from adjacent fin segments 158 by serrations 163. The fin segments 158 of adjacent disks may be circumferentially and / or longitudinally aligned or may be circumferentially and / or longitudinally offset. The fin segments 158 may be arranged in a spiral configuration, an alternating pattern, and / or a random configuration with respect to the fin segments 158 above and / or below them longitudinally.

[0032] The disk 152 may be constructed at least in part from carbon steel, alloy steel, stainless steel, aluminum, beryllium, copper, gold, magnesium, iridium, molybdenum, rhodium, silver, tungsten, and / or other suitable materials and alloys thereof. The center tube 154 may be constructed at least in part from carbon steel, alloy steel, stainless steel, ferritic stainless steel, austenitic stainless steel, and / or other materials having sufficient thermal conductivity, stress resistance, and heat resistance. While one example of the heat exchange tube 146 has been described, it will be appreciated that the heat exchange tube may take a variety of alternative forms.

[0033] 5 shows an enlarged perspective view of an upper portion 170 of the heat exchanger 108, sometimes referred to as the inlet. As shown, the upper portion 170 includes several manifolds or headers that provide distribution of the fluid 144 to the heat exchange tubes 146. For example, several manifolds 172 can direct the fluid 144 to and from various upper headers 174. The heat exchanger 108 includes multiple sets 176 of the heat exchange tubes 146 arranged adjacent to one another. Each set 176 of the heat exchange tubes 146 is fluidly coupled at one end to an (upper) header 174. That is, each upper header 174 is in fluid communication with a set 176 of the heat exchange tubes 146 to direct the fluid 144 from the manifolds 172 to the set of heat exchange tubes 146.

[0034] 5, the sets 176 of heat exchange tubes 146 are also in fluid communication with respective lower headers 178, which allows for redirection of fluid through different tubes 146 within a given set 176 of tubes 146. In the illustrated example, the sets 176 of heat exchange tubes 146 may extend vertically, as in FIG. 2, and thus, together with the associated headers 174, 178, may be referred to as "harps" because of their resemblance to the musical instrument harp. In alternative embodiments, the tubes 146 may have U-shaped ends rather than lower headers 178; see, e.g., FIGS. 3 and 7 (right side).

[0035] In the exemplary embodiment, sets 176 of heat exchange tubes 146 share a common manifold (source) 172 of fluid 144 and are arranged in rows, with each row having its own respective upper header 174. It is emphasized that sets 176 of heat exchange tubes 146 do not necessarily have to be in rows, but may be, for example, staggered, randomly positioned, temporarily offset, etc. Each set 176 may include any number of heat exchange tubes 146, for example, 38 to 50 tubes positioned across a single row. Each header 174 may be, for example, 2 to 6 meters long.

[0036] The set 176 of heat exchange tubes 146 includes a first outermost set 176A of heat exchange tubes 146, a second outermost set 176B of heat exchange tubes 146 opposite the first outermost set 176A of heat exchange tubes 146, and at least one inner set 176C of heat exchange tubes 146 between the first outermost set 176A of heat exchange tubes 146 and the second outermost set 176B of heat exchange tubes 146. Any number of sets 176 of heat exchange tubes 146 may be used. For example, anywhere from 10 to 30 sets 176 of heat exchange tubes 146 may be provided in line with the fluid 142. In the non-limiting example shown in FIG. 5, 14 sets of heat exchange tubes 176 are shown, along with 12 inner sets 176C.

[0037] According to an embodiment of the present disclosure, FIG. 6 shows a side view of two sets 176 of heat exchange tubes 146 (side by side), FIG. 7 shows an enlarged partial side view of the set 176 of heat exchange tubes 146, and FIG. 8 shows an enlarged partial perspective view of the tube restraint 190. The illustrated set may be any of the outermost or innermost sets of FIG. 5. As shown in FIGS. 6 and 7, the heat exchanger 108 includes a sensor grid 180 disposed between the sets of heat exchange tubes 146. The sensor grid 180 includes a plurality of sensors 182. The term "sensor grid" 180 is used generally herein to indicate a distributed layout or arrangement of the desired sensors 182, but is not necessarily used to describe the sensors 182 disposed in any particular spaced-apart framework.

[0038] Each sensor 182 may be any now known or later developed sensor, including, but not limited to, a thermocouple, resistance temperature detector (RTD) or other type of temperature sensor, a pressure or flow rate sensor such as a Pitot tube, a strain gauge, a gas sampling tube, etc. The sensors 182 in the sensor grid 180 do not necessarily all need to be of the same type. The sensors 182 may measure, for example, fluid temperature, tube or fin metal temperature, gas static pressure, gas velocity, tube or header strain, exhaust gas composition (e.g., oxygen, NOx, CO, CO2, hydrocarbons), particulates, ammonia slip, etc. As a result, the sensors 182 enable the collection of data to determine, for example, thermal or pressure drop performance of heat exchanger 108 sections, gas temperature or exhaust gas composition distribution, gas velocity distribution, tube or header thermal strain for evaluation of burner and emission control equipment, etc.

[0039] Each sensor 182 may include a sensor lead 184 extending therefrom. Sensors 182 may also share sensor leads 184. The sensor leads 184 may include any form of linear structure capable of communicating with one or more respective sensors 182 and the control system 138 (FIG. 1), such as electrical wire with any form of shielding, pneumatic tubes for pitot tube-type sensors, etc. The sensors 182 and sensor leads 184 are constructed of materials suitable to withstand the operating environment of the heat exchanger 108.

[0040] According to embodiments of the present disclosure, the sensor grid 180 and its respective sensors 182 can be coupled to one or more sets 176 of heat exchange tubes 146 during manufacturing. That is, the sensor grid 180 is installed during coupling of the heat exchange tubes 146 with the header 174 to form a "harp" and prior to final installation alongside multiple other sets 176 of heat exchange tubes 146 at the power plant site. Thus, in contrast to conventional heat exchanger sensor systems, the sensor grid 180 of the heat exchanger 108, once assembled at the site, can include at least one sensor 182 coupled to at least one heat exchange tube 146 in at least one inner set 176C of heat exchange tubes 146 ( FIG. 5 ). In this manner, operational data can be measured at any location and from any heat exchange tube 146 within the heat exchanger 108. Any number of sensors 182 can be used, and the sensors 182 can be arranged in any manner. 6, five thermocouples may be vertically spaced at levels TC1-TC5 of any set 176 of heat exchange tubes 146. Sensor leads 184 may be routed to any location within the heat exchanger 108.

[0041] The heat exchanger 108 also includes a tube restraint 190 for positioning at least one of the sets 176 of heat exchange tubes 146 relative to the enclosure 140. Any number of tube restraints 190 may be used within the heat exchanger 108 along any given set 176 of heat exchange tubes 146. For example, the partial views of Figures 5 and 7 show two tube restraints 190, while Figure 6 shows eight. The tube restraints 190 may be spaced in any manner necessary to support the position of the heat exchange tubes 146, for example, vertically as shown.

[0042] FIG. 8 shows a partial perspective view of a tube restraint 190 according to an embodiment of the present disclosure. Each tube restraint 190 includes a body 192 and a plurality of tube openings 194 defined in the body. Each tube opening 194 is configured to receive one heat exchange tube 146 of the set 176 of heat exchange tubes 146 therethrough (only a portion of the set is shown in FIG. 8 ). In the illustrated example, the tube opening 194 is in the form of a hole 196 in the body 192. In other embodiments, the tube opening 194 may be an open seat forming a scalloped bar. In either case, the tube restraint 190 positions the heat exchange tubes 146 and either restrains them from moving in an undesired manner or allows controlled movement via, for example, thermal expansion or a controlled actuator (not shown).

[0043] In contrast to a conventional tube restraint, the tube restraint 190 may also include a sensor lead opening 200 defined in the body 192. The sensor lead opening 200 is configured to receive the sensor leads 184 therethrough. Each tube opening 194 has a larger dimension, e.g., a larger diameter if circular, than the sensor lead openings 200. A conventional tube restraint does not require or provide sensor lead openings 200 because the sensor leads 184 are coupled to the outside of the tubes and are not necessary because the tube restraint is coupled only to the outermost set of heat exchange tubes.

[0044] Because the set 176 of heat exchange tubes 146 is manufactured with the sensor grid 180 attached, the sensors 182 of the sensor grid 180 can be positioned at desired locations on the set 176 of heat exchange tubes 146, and each sensor lead 184 can be easily placed through the sensor lead opening 200. The sensor lead opening 200 allows for collective routing of the sensor leads 184 and protection of the wires, for example, during transportation and assembly of the heat exchanger 108 in the field. Each sensor lead opening 200 can be sized to accommodate any number of sensor leads 184 placed therethrough. For example, a tube restraint 190 closer to where the sensor leads 184 exit the enclosure 140 can have a larger sensor lead opening 200 to accommodate the sensor leads of any number of downstream sensors 182.

[0045] The sensor 182 and sensor leads 184 may be coupled to the set 176 of heat exchange tubes 146 in any now known or later developed manner, such as, but not limited to, a wire tie to the tubes 146 and / or tube restraint 190. The sensor 182 may be operably positioned as needed to measure a desired operating parameter, such as temperature. The sensor leads 184 may include an expansion bend 202 therein to accommodate thermal expansion / contraction of the heat exchanger 108, as shown in enlarged cross section in FIG. 6 .

[0046] FIG. 9 shows an enlarged perspective view of the ends of a pair of adjacent headers 174A, 174B, and FIG. 10 shows an end view of the pair of adjacent headers 174A, 174B. Referring to the enlarged perspective views of FIGS. 5 and 9, the ends of adjacent headers 174 (174A, 174B in FIG. 9) do not extend to the same length (they have non-coplanar ends). The ends of the headers 174 may alternate in length, as shown in FIG. 5. More specifically, as best shown in FIG. 9, the end 210 of the header 174A of the first set 176D of heat exchange tubes 146 does not extend longitudinally to the same extent as the end 212 of the adjacent header 174B of the second set 176E of heat exchange tubes 146. As shown in Figures 9 and 10 (but not Figure 5 for clarity), the shorter header 174A includes a baffle 220 extending from its end to, for example, prevent the fluid 142 from migrating upward through gaps or otherwise direct the fluid 142 in a desired manner through the heat exchanger 108. The baffle 220 can extend to the same longitudinal extent of the adjacent header 174B. That is, the end 212 of the header 174B of the second set 176E of heat exchange tubes 146 adjacent to the header 174A of the first set 176D of heat exchange tubes 146 can extend the same length as the baffle 220 from the end 210 of the header 174A of the first set 176D of heat exchange tubes 146.

[0047] The sensor leads 184 may need to extend upward between any two adjacent sets 176D, 176E (inner or outermost sets) of heat exchange tubes 146. To direct the sensor leads 184 to the baffle 220, the heat exchanger 108 may also include a conduit 222 extending through the baffle 220. The conduit 222 may include multiple sensor leads 184 of the sensor grid 180 ( FIG. 5 ) extending therethrough. In this manner, the sensor leads 184 may be routed through the baffle 220. The conduit 222 may take various forms, but in the illustrated example, includes a first length 230 extending along the end 210 of the header 174A of the first set 176D of heat exchange tubes 146 and a second length 232 extending along the length of the header 174A of the first set 176D of heat exchange tubes 146. If desired, the first length 230 may be fixedly coupled to the end 210 of the header 174A, for example, by a gusset or other connection. While not necessary in all cases, the first length 230 may be at a substantially perpendicular angle to the second length 232. The conduit 222 may have any cross-sectional shape and may be formed into sections that are subsequently fastened together, for example, by welding, to allow for routing of the sensor lead 184 therethrough, for example, if the sensor lead 184 is not very flexible. For example, the conduit 222 may include a pair of longitudinally extending sections 234, 236 coupled together, e.g., half sections joined along a weld joint 238. The conduit 222 may be made of any material capable of withstanding the environment of the heat exchanger 108.

[0048] The sensor leads 184 may be routed along headers 174A, 174B and ultimately out through the enclosure 140. In FIG. 5 , the sensor leads 184 are shown exiting through the roof 224 of the enclosure 140, but they may extend through any portion of the enclosure 140. The sensor leads 184 may be coupled to the control system 138 ( FIG. 1 ) in any now known or later developed manner for operational control of any number of components of the CCPP 100.

[0049] Embodiments of the present disclosure also include a tube restraint 190 and a CCPP 100, as described herein. It is emphasized that while a particular type of power plant and a particular type of CCPP 100 are described herein, the teachings of the present disclosure are applicable to any type of heat exchanger.

[0050] As described herein, embodiments of the present disclosure enable the sensor grid 180 to be installed along any set 176 of heat exchange tubes 146. Thus, the sensor grid 180 can provide data about any portion of the heat exchanger 108, even for the inner set 176C of heat exchange tubes 146 (FIG. 5). Installing the sensor grid 180 during set manufacturing is easier and faster than field installation, eliminating the need to install the sensor grid 180 along critical paths in the field construction schedule. The sensor grid 180 also supports online performance monitoring, active control of CCPP 100 efficiency optimization, and lifespan monitoring and optimization of heat exchanger 108 components.

[0051] As used herein throughout the specification and claims, approximation language can be applied to modify any quantitative expression that can reasonably vary without resulting in a change in the relevant basic function. Thus, values ​​modified by terms such as "approximately," "about," and "substantially" are not limited to the exact value specified. In at least some instances, approximation language can correspond to the precision of the measuring instrument used to measure the value. Here, and throughout the specification and claims, range limitations are combinable and / or interchangeable, and unless the context and language dictate otherwise, such ranges are identified and include all subranges encompassed therein. "About," as applied to a particular value in a range, applies to both endpoints and can indicate + / - 10% of the stated value, unless specifically dependent on the precision of the measuring instrument used to measure the value.

[0052] The corresponding structure, material, acts, and equivalents of all means-plus-function or step-plus-function elements in the following claims are intended to encompass any structure, material, or acts for performing that function in combination with other specifically claimed claim elements. The description of the present disclosure has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise form disclosed. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the disclosure. The present embodiments were chosen and described in order to best explain the principles and practical application of the disclosure and to enable others skilled in the art to understand the disclosure in its various embodiments with various modifications as suited to the particular uses envisioned. [Explanation of symbols]

[0053] 100 Combined Cycle Power Plants (CCPPs) 102 Gas Turbine (GT) System 104 Generator 106 Compressor / turbine shaft, rotating shaft 108 Heat exchanger, heat recovery steam generator (HRSG) 110 Steam Turbine (ST) System 112 Second Generator 120 Compressor 124 Combustor 126 Combustion Zone 128 Fuel Nozzle Assembly 130 Gas Turbine 132 Steam turbines, high pressure (HP) turbines 134 Steam turbines, intermediate pressure (IP) turbines 136 Steam turbines, low pressure (LP) turbines 138 CCPP Control System 140 Insulated Enclosure 142 Fluid 144 Fluid 146 Heat exchange tube 148 Heat Exchanger Enclosure 150 exhaust system 152 discs 154 Central tube 156 Longitudinal 158 Fin Segments 160 Center of the disc 163 Serration 170 Upper part 172 Manifold 174 Upper Header 174A Header 174B Header 176 Heat Exchanger Tube Set, Heat Exchanger Tube 176A First outermost set 176B Second outermost set 176C Inner Set 176D 1st set 176E 2nd set 178 Lower Header 180 Sensor Grid 182 downstream sensor 184 Sensor lead wire 190 Pipe restraint part 192 Main Unit 194 Pipe opening 196 holes 200 Sensor lead opening 202 Expansion bend 210 End 212 End 220 Baffle 222 Conduit 224 Roof 230 First Length 232 Second Length 234 Longitudinal portion 236 Longitudinal portion 238 Welded Joints

Claims

1. A heat exchanger (108), comprising: a plurality of sets (176) of heat exchange tubes (146) disposed adjacent to one another, each set (176) of heat exchange tubes (146) fluidly coupled at an end thereof to a header (174); a sensor grid (180) disposed between the plurality of sets (176) of heat exchange tubes (146), the sensor grid (180) including a plurality of sensors (182), each sensor (182) including a sensor lead (184) extending therefrom; a tube restraint (190) for positioning at least one of the plurality of sets (176) of heat exchange tubes (146) relative to the enclosure (148), the tube restraint (190) including a tube opening (194) for each of the heat exchange tubes (146) of each set (176) of heat exchange tubes (146) and a sensor lead opening (200); It contains At least one sensor lead (184) of the sensor grid (180) extends through the sensor lead opening (200); the end (210) of the header (174) of the first set (176D) of heat exchange tubes (146) includes a baffle (220) extending therefrom; The heat exchanger (108) further includes a conduit (222) extending through the baffle (220), the conduit (222) including a plurality of sensor leads (184) of the sensor grid (180) extending therethrough.

2. 2. The heat exchanger of claim 1, wherein the plurality of sets of heat exchange tubes includes a first outermost set of heat exchange tubes, a second outermost set of heat exchange tubes, and at least one inner set of heat exchange tubes between the first outermost set of heat exchange tubes and the second outermost set of heat exchange tubes, and the sensor grid includes at least one sensor coupled to at least one heat exchange tube in the at least one inner set of heat exchange tubes.

3. 2. The heat exchanger of claim 1, wherein an end portion of the header of a second set of heat exchange tubes adjacent to the header of the first set of heat exchange tubes extends from the end portion of the header of the first set of heat exchange tubes to the same length as the baffle.

4. 2. The heat exchanger of claim 1, wherein the conduit includes a first length extending along the end of the header of the first set of heat exchange tubes and a second length extending along the length of the header of the first set of heat exchange tubes.

5. The heat exchanger (108) of claim 4, wherein the first length (230) is fixedly coupled to the end (210) of the header (174).

6. The heat exchanger (108) of claim 4, wherein the first length (230) is at a substantially perpendicular angle to the second length (232).

7. The heat exchanger (108) of any preceding claim, wherein the conduit (222) comprises a pair of longitudinally extending portions (234, 236) joined together.

8. A combined cycle power plant (CCPP) (100), comprising: a gas turbine system (102); a steam turbine system (110); a heat recovery steam generator (108) coupled to the gas turbine system (102) for generating steam for the steam turbine system (110) using the exhaust of the gas turbine system (102); The heat recovery steam generator (108) includes: an enclosure (148) configured to direct said exhaust air therethrough; A heat exchanger (108) according to any one of claims 1 to 7; a combined cycle power plant (CCPP) (100) including:

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