Axial Flow Turbine

Abstract

To provide an axial flow turbine which can adjust a temperature of a cooling medium for cooling a turbine component in consideration of thermal stress.SOLUTION: An axial flow turbine 1 of this embodiment comprises a turbine component which is cooled by a cooling medium. The axial flow turbine 1 comprises a second cooling medium introduction mechanism 100B for introducing a third cooling medium which is adjusted so that a temperature difference between a high-temperature part and a low-temperature part of the turbine component satisfies a thermal stress allowable temperature into the axial flow turbine 1 as the cooling medium of the turbine component by mixing a first cooling medium and a second cooling medium which is higher than the first cooling medium in a temperature.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to an axial flow turbine. [Background technology]

[0002] Systems that use high-temperature working fluid to rotate an axial turbine to generate electricity include gas turbine power generation equipment and supercritical CO 2 It is installed in gas turbine power generation equipment, steam turbine power generation equipment, etc.

[0003] In such power generation facilities, efforts are being made to increase the turbine inlet temperature in order to improve thermal efficiency, which can cause the temperature of the working fluid to exceed the heat-resistant temperature of turbine members that constitute the axial flow turbine.

[0004] For this reason, such an axial flow turbine is provided with a cooling system that cools the turbine components with a cooling medium. For example, one example of a cooling structure in the cooling system is a structure in which the cooling medium is introduced into the inside of the stator blades. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6505860 Summary of the Invention [Problem to be solved by the invention]

[0006] In the stator vane of the axial flow turbine equipped with the above-mentioned conventional cooling system, there is an outer surface exposed to the high-temperature working fluid and an inner surface exposed to the cooling medium. Thermal stress occurs due to the temperature difference between the outer surface and the inner surface. This thermal stress increases as the temperature difference between the outer surface and the inner surface increases.

[0007] Such thermal stress occurs not only in the stator blades but also in any turbine component where the above-mentioned temperature difference occurs. Since this thermal stress affects the strength of the turbine component, it is preferable that it is as small as possible.

[0008] However, in axial turbines with conventional cooling systems, the turbine components are cooled by the cooling medium without due consideration of thermal stresses based on the temperatures of the hot parts of the turbine components and the temperatures of the cold parts of the turbine components that are cooled by the cooling medium, which can cause damage to the turbine components due to thermal stresses.

[0009] The problem to be solved by the present invention is to provide an axial flow turbine capable of adjusting the temperature of a cooling medium that cools turbine components, taking into account thermal stress. [Means for solving the problem]

[0010] An axial flow turbine according to an embodiment includes a turbine component cooled by a cooling medium, and a cooling medium introduction mechanism that introduces a third cooling medium, which is adjusted by mixing a first cooling medium with a second cooling medium having a temperature higher than that of the first cooling medium, into the axial flow turbine as a cooling medium for the turbine component, the third cooling medium being adjusted so that a temperature difference between a high-temperature portion and a low-temperature portion of the turbine component satisfies a thermal stress allowable temperature. The thermal stress allowable temperature is set according to each of the divided ranges obtained by dividing the pressure difference (Pt1-Pt2) between the assumed pressure (Pt1) of the third cooling medium introduced into the axial turbine and the assumed pressure (Pt2) of the space into which the third cooling medium is introduced to cool the turbine components, into predetermined pressure ranges, and the thermal stress allowable temperature is selected based on the pressure difference (Pm1-Pm2) between the detected pressure (Pm1) of the third cooling medium introduced into the axial turbine and the detected pressure (Pm2) of the space into which the third cooling medium is introduced to cool the turbine components. [Brief description of the drawings]

[0011] [Figure 1] 1 is a system diagram of a gas turbine facility including an axial flow turbine according to an embodiment. [Diagram 2] 1 is a diagram showing a meridian section of an axial flow turbine according to an embodiment; [Diagram 3] 3 is an enlarged view of the configuration of a cross-sectional portion surrounded by a dashed line in FIG. 2. [Figure 4] 2 is a block diagram showing a configuration of a control device for a cooling medium temperature adjustment mechanism in an axial flow turbine according to an embodiment. FIG. [Diagram 5]4 is a flowchart illustrating an operation of a coolant temperature adjustment mechanism in the axial flow turbine according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0013] 1 is a system diagram of a gas turbine facility 300 equipped with an axial turbine 1 according to an embodiment. Here, the gas turbine facility 300 is a supercritical CO 2 An example of a turbine installation will be described.

[0014] First, an outline of the configuration of the gas turbine facility 300 will be described.

[0015] 1, the gas turbine facility 300 includes a combustor 310, an axial flow turbine 1, a generator 320, a regenerative heat exchanger 330, a cooler 340, and a compressor 350. The gas turbine facility 300 also includes a circulation pipe 360 ​​for circulating a portion of the combustion gas discharged from the axial flow turbine 1 to a system.

[0016] The combustor 310 combusts fuel and an oxidizer. The combustor 310 includes a fuel pipe 311 for supplying fuel and an oxidizer pipe 313 for supplying the oxidizer. The fuel pipe 311 includes a flow rate control valve 312 for adjusting the flow rate of the fuel. The oxidizer pipe 313 includes a flow rate control valve 314 for adjusting the flow rate of the oxidizer.

[0017] Here, as the fuel, for example, a hydrocarbon such as methane or natural gas is used. In addition, as the fuel, for example, a coal gasification gas fuel containing carbon monoxide and hydrogen can also be used. As the oxidizing agent, oxygen or CO circulated to the oxygen can be used. 2 Gas mixtures such as those containing benzene and carbon dioxide are used.

[0018] Combustion gas generated in the combustor 310 and CO circulated to the combustor 310 through the circulation pipe 360 2 The gas passes through a transition piece 315 and is introduced into the axial flow turbine 1 as a working fluid.

[0019] The axial flow turbine 1 is rotated by the working fluid. A generator 320 is connected to the axial flow turbine 1. The axial flow turbine 1 includes a cooling medium introduction mechanism 100 for introducing a cooling medium for cooling turbine components. The cooling medium introduction mechanism 100 includes a first cooling medium introduction mechanism 100A and a second cooling medium introduction mechanism 100B. The second cooling medium introduction mechanism 100B includes a cooling medium temperature adjustment mechanism 200. The cooling medium introduction mechanism 100 will be described later.

[0020] The regenerative heat exchanger 330 exchanges the working fluid discharged from the axial flow turbine 1 with the circulating CO 2 that has been cooled by the cooler 340 and pressurized by the compressor 350. 2 Heat exchange takes place between the gas and the heat exchanger.

[0021] The cooler 340 cools the working fluid whose temperature has been reduced by heat exchange in the regenerative heat exchanger 330. The water vapor in the working fluid is condensed into water as it passes through the cooler 340. This water is discharged to the outside through, for example, a drain pipe 361.

[0022] Here, the flow rates of the fuel and oxidant supplied to the combustor 310 are adjusted to, for example, a stoichiometric mixture ratio (equivalent ratio of 1). In this case, the components of the working fluid from which water vapor has been removed are almost entirely CO 2 It is.

[0023] The compressor 350 is a 2 Gas is pressurized and pumped. CO 2 The gas is compressed by the compressor 350 to a pressure equal to or higher than the critical pressure, and becomes a supercritical fluid.

[0024] A discharge pipe 362 is connected to the circulation pipe 360 ​​between the compressor 350 and the regenerative heat exchanger 330. 2A part of the gas is discharged to the outside through the discharge pipe 362. The discharge pipe 362 is provided with a flow rate adjustment valve 363 for adjusting the discharge flow rate.

[0025] Remaining boosted CO 2 The gas flows into the regenerative heat exchanger 330 where it is heated. The heated CO 2 The gases are recycled to the combustor 310 .

[0026] (Axial Turbine 1) Next, the configuration of the axial flow turbine 1 will be described.

[0027] Fig. 2 is a diagram showing a meridian section of the axial flow turbine 1 according to the embodiment. Fig. 3 is an enlarged view of the configuration of a cross-sectional portion A surrounded by a dashed line in Fig. 2.

[0028] As shown in Fig. 2, the axial flow turbine 1 includes an outer casing 10 and an inner casing 11 provided inside the outer casing 10. The inner casing 11 is, for example, composed of a high-pressure side inner casing 11a and a low-pressure side inner casing 11b.

[0029] The low-pressure inner casing 11b includes a packing head 12 disposed on the inner circumferential side facing the turbine rotor 20, downstream of the final turbine stage.

[0030] Here, an example is shown in which the inner casing 11 is configured with a high-pressure side inner casing 11a and a low-pressure side inner casing 11b, but the configuration is not limited to this. The inner casing 11 may be configured with a single casing along the turbine rotor axial direction. In the following, the turbine rotor axial direction will be simply referred to as the axial direction.

[0031] In addition, although a double casing including the outer casing 10 and the inner casing 11 is illustrated here as an example of the casing, the present invention is not limited to this. The casing may be a single casing.

[0032] The turbine rotor 20 is provided penetrating the inner casing 11 and the outer casing 10. Both ends of the turbine rotor 20 are rotatably supported by bearings (not shown).

[0033] 2 and 3, an outer shroud 30 is provided around the inner periphery of the inner casing 11 in the circumferential direction. An inner shroud 40 is provided around the inside (radially inward) of the outer shroud 30 in the circumferential direction. A plurality of stator vanes 50 are supported in the circumferential direction between the outer shroud 30 and the inner shroud 40 to form a stator vane cascade. A plurality of stages of the stator vane cascade are provided in the axial direction.

[0034] Here, the radially inner side refers to the side (the side of the central axis O) approaching the central axis O of the turbine rotor 20 in the radial direction. The radial direction is a direction perpendicular to the central axis O, with the central axis O as the base point.

[0035] A heat shield piece 45 is provided on the inside of the inner shroud 40 along the circumferential direction so as to face the inner shroud 40. As shown in Fig. 3, the heat shield piece 45 includes a heat shield plate 46 and a support portion 47. The heat shield plate 46 is formed of a plate-like member disposed so as to face the inner shroud 40. A space 49 is formed between the heat shield plate 46 and the turbine rotor 20.

[0036] Further, at least one through hole 48 is formed in the heat shield 46, which connects the space on the inner shroud 40 side with a space 49. The support portion 47 supports the heat shield 46. One end of the support portion 47 is connected to the heat shield 46, and the other end is attached to the turbine rotor 20.

[0037] The inner circumferential surface of the inner shroud 40 is provided with seal fins 42. A seal portion is formed between the inner shroud 40 and a heat shield piece 45. The inner shroud 40 is formed with a through hole 41 that communicates with this seal portion. This through hole 41 also communicates with a cooling passage 51 in a stator blade 50, which will be described later.

[0038] The rotor wheels 21 protrude radially outward from the outer circumferential surface of the turbine rotor 20 in the circumferential direction. The rotor wheels 21, which are made up of annular protrusions, are provided in multiple stages in the axial direction. Here, the radially outward side refers to the side that moves away from the central axis O in the radial direction.

[0039] A plurality of rotor blades 60 are circumferentially attached to the tip of each rotor wheel 21 to form a rotor blade cascade. As shown in Fig. 3, for example, in a downstream turbine stage, a communication hole 22 is formed between the attachment portion 62 of the rotor blade 60 and the rotor wheel 21, which communicates with the downstream turbine stage.

[0040] The outer periphery of the rotor blade 60 is surrounded by, for example, a shroud segment 61. The shroud segment 61 is supported by the outer shroud 30 and the inner casing 11.

[0041] The stator blade cascade and the rotor blade cascade are arranged alternately in the axial direction. A turbine stage is composed of a stator blade cascade and a rotor blade cascade immediately downstream of the stator blade cascade. A working fluid flow path 65 through which the working fluid flows is formed by the multiple turbine stages.

[0042] As shown in Fig. 2, on the high-pressure side (the axial left side of Fig. 2), a gland seal portion 25 is provided between the turbine rotor 20 and the outer casing 10, and a gland seal portion 26 is provided between the turbine rotor 20 and the inner casing 11. On the low-pressure side (the axial right side of Fig. 2), a gland seal portion 27 is provided between the turbine rotor 20 and the packing head 12, and a gland seal portion 28 is provided between the turbine rotor 20 and the packing head 13. These gland seal portions 25, 26, 27, 28 suppress leakage of the working fluid and the cooling medium to the outside.

[0043] An exhaust chamber 70 for discharging the working fluid is formed downstream of the final turbine stage. A part of the exhaust chamber 70 is formed by the inner casing 11b and the packing head 12. In addition, a circulation pipe 360 ​​is connected to the exhaust chamber 70.

[0044] As shown in FIG. 3, the packing head 12 includes a seal fin 15 that protrudes axially upstream from an upstream end face 12a.

[0045] The rotor blade 60 of the final stage is provided with a seal fin 63 that protrudes from a downstream end face 62a of the implant portion 62 toward the downstream side in the axial direction.

[0046] The tip of the seal fin 63 is disposed so as to be shifted in the radial direction so as not to come into contact with the tip of the seal fin 15. In other words, the tip of the seal fin 63 is disposed so as to overlap with the tip of the seal fin 15 with a radial gap therebetween so as not to come into contact with the tip of the seal fin 15. Note that, here, an example is shown in which the tip of the seal fin 63 is located radially inward of the tip of the seal fin 15.

[0047] The seal portion 29 is formed by the tip portion of the seal fin 63 and the tip portion of the seal fin 15. In this manner, the seal portion 29 is provided between the embedding portion 62 of the rotor blade 60 of the final stage and the packing head 12.

[0048] Here, the annular space surrounded by the seal portion 29, the implant portion 62 of the final stage rotor blade 60, the final stage rotor wheel 21, the gland seal portion 27, the packing head 12, and the turbine rotor 20 functions as a wheel space 80. The seal portion 29 prevents the working fluid discharged from the final stage turbine stage from flowing into the wheel space 80.

[0049] 2, the axial flow turbine 1 is provided with a transition piece 315 penetrating the outer casing 10 and the inner casing 11. The downstream end of the transition piece 315 abuts against the upstream ends of the inner shroud 40 and the outer shroud 30 that support the first-stage stator vane 50. The transition piece 315 guides the working fluid discharged from the combustor 310 to the first-stage stator vane 50.

[0050] In a penetration region where the transition piece 315 penetrates the outer casing 10 and the inner casing 11, the outer periphery of the transition piece 315 is covered with a cooling medium introduction pipe 110 that introduces a cooling medium. That is, in the penetration region, a double pipe structure is provided consisting of the transition piece 315 and the cooling medium introduction pipe 110 provided on the outer periphery side of the transition piece 315. The downstream end of the cooling medium introduction pipe 110 is extended to the inside of the penetration opening of the inner casing 11 through which the transition piece 315 penetrates. The piping system of the cooling medium introduction pipe 110 will be described later.

[0051] In the above-described axial flow turbine 1, the working fluid guided from the transition piece 315 to the first-stage stator vane 50 flows through the working fluid passage 65 while performing expansion work, and rotates the turbine rotor 20. This rotation of the turbine rotor 20 drives the generator 320 to generate electricity. The working fluid that has passed through the final turbine stage flows from the exhaust chamber 70 into the circulation piping 360.

[0052] (Cooling medium introduction mechanism 100) Next, the cooling medium introduction mechanism 100 will be described.

[0053] The cooling medium introduction mechanism 100 introduces a cooling medium for cooling turbine components constituting the axial flow turbine 1 to the axial flow turbine 1. The cooling medium introduction mechanism 100 includes a first cooling medium introduction mechanism 100A and a second cooling medium introduction mechanism 100B.

[0054] (First cooling medium introduction mechanism 100A) First, the first cooling medium introduction mechanism 100A will be described.

[0055] The first cooling medium introduction mechanism 100A includes a cooling medium introduction pipe 110 and a flow rate adjustment valve 111, as shown in FIG.

[0056] One end of the cooling medium introduction pipe 110 is connected to, for example, the circulation pipe 360 ​​between the regenerative heat exchanger 330 and the combustor 310. The other end of the cooling medium introduction pipe 110 is connected to the axial flow turbine 1. Specifically, as described above with reference to FIG. 2, the other end of the cooling medium introduction pipe 110 penetrates the outer casing 10 and the inner casing 11 so as to surround the outer periphery of the transition piece 315.

[0057] As shown in FIG. 1, an annular passage 112 is formed between the cooling medium introduction pipe 110 and the transition piece 315 at this penetration portion.

[0058] CO heated by regenerator 330 2 A part of the gas passes through the cooling medium introduction pipe 110 and is introduced as a cooling medium from the annular passage 112 around the transition piece 315 into the space 14 in the inner casing 11a. The temperature of the cooling medium introduced into the space 14 is sufficiently lower than the temperature of the working fluid introduced into the first stage stator blades 50. The pressure of the cooling medium introduced into the space 14 is higher than the pressure of the working fluid introduced into the first stage stator blades 50.

[0059] Here, the cooling medium introduced into the space 14 is used not only to cool the transition piece 315 but also to cool, for example, the turbine rotor 20 and turbine components that constitute the turbine stages.

[0060] (Second cooling medium introduction mechanism 100B) Next, the second cooling medium introduction mechanism 100B will be described.

[0061] The second cooling medium introduction mechanism 100B adjusts the temperature of the cooling medium so that the temperature difference between the high temperature and low temperature parts of the turbine component being monitored for thermal stress satisfies the thermal stress permissible temperature Tp, and introduces the cooling medium into the axial flow turbine 1. Specifically, the second cooling medium introduction mechanism 100B introduces the temperature-adjusted cooling medium into the inlet of a cooling medium introduction passage 150 that leads the cooling medium to the turbine component. In the following, the turbine component being monitored for thermal stress will be simply referred to as the turbine component.

[0062] Here, the thermal stress allowable temperature Tp means the temperature difference between the high temperature part and the low temperature part of the turbine component when allowable thermal stress occurs in the turbine component. This thermal stress allowable temperature Tp has a temperature range of not less than the lower limit thermal stress allowable temperature Tpl and not more than the upper limit thermal stress allowable temperature Tpu.

[0063] The lower limit thermal stress allowable temperature Tpl is set in consideration of the temperature at which a cooling effect can be obtained, and the upper limit thermal stress allowable temperature Tpu is set in consideration of the maximum allowable thermal stress.

[0064] Although the configuration in which the second cooling medium introduction mechanism 100B introduces the cooling medium to the turbine components in the low-pressure inner casing 11b is described here as an example, the present invention is not limited to this. The second cooling medium introduction mechanism 100B may introduce the cooling medium to the turbine components in the high-pressure inner casing 11a.

[0065] Here, examples of turbine components cooled by the cooling medium introduced from the second cooling medium introduction mechanism 100B include the stator blades 50, the outer shroud 30, and the like.

[0066] First, the cooling medium introduction passage 150 formed in the axial flow turbine 1 will be described.

[0067] Here, a flow passage for cooling the stator blade 50 is exemplified as the cooling medium introduction flow passage 150. As shown in Fig. 3, the cooling medium introduction flow passage 150 for cooling the stator blade 50 includes an axial passage 151 and a radial passage 152 formed in the inner casing 11b, the space 31 of the outer shroud 30, and a cooling passage 51 in the stator blade 50.

[0068] The axial passage 151 is formed of a hole extending along the axial direction. The radial passage 152 is formed of a hole extending radially inward from the axial passage 151. The radial passage 152 is in communication with the space 31 of the outer shroud 30.

[0069] In this case, the cooling medium introduced into the cooling medium introduction passage 150 passes through the axial passage 151, the radial passage 152, and the space 31 of the outer shroud 30, and flows into the cooling passage 51 in the stator blade 50. The cooling medium passes through, for example, the through hole 41 of the inner shroud 40 and is discharged from the stator blade 50. The stator blade 50 is cooled by the cooling medium flowing through the cooling passage 51.

[0070] Moreover, the cooling medium introduction passage 150 for cooling the outer shroud 30 is configured from a part of the cooling medium introduction passage 150 for cooling the above-mentioned stator vane 50. Specifically, the cooling medium introduction passage 150 for cooling the outer shroud 30 includes an axial passage 151, a radial passage 152, and the space 31 of the outer shroud 30. The action of the cooling medium introduced into the cooling medium introduction passage 150 is as described above. The outer shroud 30 is cooled by the cooling medium introduced into the space 31.

[0071] The cooling medium that has passed through the inside of the stator blade 50 passes through the through-hole 41 of the inner shroud 40 and the through-hole 48 of the heat shield 46, and is introduced into the space 49. The cooling medium that has been introduced into the space 49 passes through the communication hole 22 and flows into the wheel space 80.

[0072] Next, the configuration of the second cooling medium introduction mechanism 100B will be described.

[0073] The second cooling medium introduction mechanism 100B includes a cooling medium temperature adjustment mechanism 200.

[0074] As shown in FIG. 1, the cooling medium temperature control mechanism 200 includes a low-temperature side piping 210, a low-temperature side flow rate control valve 211, a high-temperature side piping 220, a high-temperature side flow rate control valve 221, control piping 230, a low-temperature section temperature detection unit 240, a high-temperature section temperature detection unit 250, a cooling medium pressure detection unit 241, a turbine internal pressure detection unit 251, and a control device 260.

[0075] The low-temperature side pipe 210 is connected to the circulation pipe 360 ​​upstream (compressor 350 side) of the position where the high-temperature side pipe 220 is connected to the circulation pipe 360. 2 The temperature of the gas is determined by the 2 The temperature of the CO introduced into the low-temperature side pipe 210 is lower than that of the CO 2 The gas acts as a first cooling medium and is introduced into the high temperature side pipe 220. 2 The gas acts as a second cooling medium.

[0076] 1 , one end of the low-temperature side piping 210 is connected to, for example, a circulation piping 360 between the compressor 350 and the regenerative heat exchanger 330. One end of the high-temperature side piping 220 is connected to, for example, a circulation piping 360 between the regenerative heat exchanger 330 and the combustor 310. In this case, one end of the high-temperature side piping 220 may be connected to the circulation piping 360 inside the regenerative heat exchanger 330.

[0077] Also, for example, when one end of the low-temperature side piping 210 is connected to the circulation piping 360 within the regenerative heat exchanger 330, one end of the high-temperature side piping 220 is connected to the circulation piping 360 downstream (towards the combustor 310) of the position where one end of the low-temperature side piping 210 is connected to the circulation piping 360.

[0078] That is, the high temperature side pipe 220 is connected to the low temperature side pipe 210. 2 CO at a temperature higher than the gas temperature 2It is sufficient that the gas is connected to the circulation pipe 360 ​​so that the gas can be introduced therein.

[0079] The other ends of the low temperature side pipe 210 and the high temperature side pipe 220 are connected to one end of the adjustment pipe 230 at the connection part 230a. 2 The gas flow passage is unified into a single adjustment pipe 230.

[0080] The other end of the adjustment pipe 230 is connected to the axial flow turbine 1. Specifically, as shown in Fig. 2 and Fig. 3, the other end of the adjustment pipe 230 is connected to the inlet of the cooling medium introduction passage 150 (the inlet of the axial passage 151).

[0081] CO 2 In order to adjust the flow rate of the gas, the low-temperature side pipe 210 is provided with a low-temperature side flow rate adjustment valve 211, and the high-temperature side pipe 220 is provided with a high-temperature side flow rate adjustment valve 221.

[0082] Here, the CO introduced into the axial flow turbine 1 from the adjustment pipe 230 2 The gas functions as a cooling medium for cooling turbine components such as the stator blades 50 and the outer shroud 30. In the following, the CO 2 The gas is called the cooling medium. This cooling medium functions as the third cooling medium.

[0083] The temperature of the cooling medium introduced into the axial flow turbine 1 from the adjustment pipe 230 is lower than the temperature of the working fluid flowing through the turbine stage to which the cooling medium is introduced. Furthermore, the pressure of this cooling medium is higher than the pressure of the working fluid flowing through the turbine stage to which the cooling medium is introduced.

[0084] The low-temperature section temperature detection unit 240 detects the temperature of a low-temperature section in a turbine component that is cooled by a cooling medium. The low-temperature section temperature detection unit 240 is provided in the adjustment pipe 230, for example, as shown in Fig. 2 and Fig. 3. Specifically, as shown in Fig. 3, the low-temperature section temperature detection unit 240 is provided at the end of the adjustment pipe 230 on the cooling medium introduction passage 150 side. In this case, the low-temperature section temperature detection unit 240 detects the temperature of the cooling medium introduced from the adjustment pipe 230 to the axial flow turbine 1 (cooling medium introduction passage 150).

[0085] Here, when the turbine component is a stator vane 50, the low-temperature section temperature detection unit 240 is provided in a position close to the stator vane 50, so it can be assumed that the temperature of the cooling medium introduced into the cooling medium introduction passage 150 detected by the low-temperature section temperature detection unit 240 is approximately equal to the temperature of the inner surface of the cooling passage 51 of the stator vane 50 into which the cooling medium is introduced. Note that the low-temperature section temperature detection unit 240 may be provided on the inner surface of the cooling passage 51.

[0086] Furthermore, when the turbine component is the outer shroud 30, the low-temperature section temperature detection unit 240 is provided in a position close to the outer shroud 30, so it can be assumed that the temperature of the cooling medium introduced into the cooling medium introduction passage 150 detected by the low-temperature section temperature detection unit 240 is substantially equal to the temperature of the inner surface of the space 31 of the outer shroud 30 where the cooling medium is introduced. Note that the low-temperature section temperature detection unit 240 may be provided on the inner surface of the space 31.

[0087] Here, the temperature detected by the low-temperature section temperature detection section 240 is used as the temperature of the low-temperature section in the vane 50 or the outer shroud 30 when thermal stress is taken into consideration. Note that thermal stress is taken into consideration based on the temperature difference between the high-temperature section and the low-temperature section. Also, the low-temperature section temperature detection section 240 functions as a first temperature detection section.

[0088] The cooling medium pressure detection unit 241 detects the amount of CO introduced from the adjustment pipe 230 to the axial flow turbine 1 (the cooling medium introduction passage 150). 2The coolant pressure detector 241 detects the pressure of the gas. The coolant pressure detector 241 is provided, for example, in the adjustment pipe 230. Specifically, as shown in Fig. 3, the coolant pressure detector 241 is provided, for example, at the end of the adjustment pipe 230 on the coolant introduction channel 150 side.

[0089] The position of the cooling medium pressure detection unit 241 is not limited to this as long as the cooling medium pressure detection unit 241 is disposed at a position where the pressure of the cooling medium introduced into the cooling medium introduction channel 150 as the cooling medium can be detected.

[0090] The high-temperature section temperature detector 250 detects the temperature of a high-temperature section of a turbine component that is cooled by a cooling medium.

[0091] When the turbine component is a stator vane 50, as shown in Figures 2 and 3, the high temperature section temperature detection unit 250 is installed, for example, on the external surface of the trailing edge at the radially outer end of the stator vane 50. The high temperature section temperature detection unit 250 may also be installed on the external surface of the leading edge at the radially outer end of the stator vane 50. The high temperature section temperature detection unit 250 may also be installed near the external surface of the trailing edge or the external surface of the leading edge. In this case, it can be assumed that the temperature of the external surface is approximately equal to the temperature of the working fluid flowing near the external surface.

[0092] Although not shown, when the turbine component is the outer shroud 30, the high temperature section temperature detection unit 250 is installed, for example, on the outer surface of the outer shroud 30. Note that the high temperature section temperature detection unit 250 may be installed near the outer surface of the outer shroud 30. In this case, it can be assumed that the temperature of the outer surface is approximately equal to the temperature of the working fluid flowing near the outer surface.

[0093] Here, when considering thermal stress, the temperature detected by the high-temperature portion temperature detection unit 250 is used as the temperature of the high-temperature portion in the stator blade 50 or the outer shroud 30. Note that the high-temperature portion temperature detection unit 250 functions as a second temperature detection unit.

[0094] The turbine internal pressure detection unit 251 detects the pressure in a space at a predetermined location into which a cooling medium is introduced to cool turbine components.

[0095] When the turbine component is a stator vane 50, the turbine internal pressure sensing unit 251 is disposed in a cooling passage 51 in the stator vane 50. When the turbine component to be monitored for thermal stress is an outer shroud 30, the turbine internal pressure sensing unit 251 is disposed in a space 31 in the outer shroud 30.

[0096] As described above, the high temperature section temperature detector 250 and the turbine internal pressure detector 251 are installed in pairs at corresponding positions.

[0097] The pair of high-temperature section temperature detector 250 and turbine internal pressure detector 251 are installed at any one of the installation locations for the above-mentioned turbine components. That is, the second cooling medium introduction mechanism 100B (cooling medium temperature adjustment mechanism 200) adjusts the temperature of the cooling medium in consideration of the thermal stress in any one of the turbine components, such as the stator blade 50 and the outer shroud 30.

[0098] The control device 260 controls the low-temperature side flow rate control valve 211 and the high-temperature side flow rate control valve 221 to adjust the temperature of the cooling medium introduced into the axial flow turbine 1 so that the temperature difference between the high-temperature part and the low-temperature part in the turbine component satisfies the thermal stress permissible temperature Tp. Specifically, the control device 260 controls the low-temperature side flow rate control valve 211 and the high-temperature side flow rate control valve 221 to adjust the temperature of the cooling medium, thereby adjusting the temperature of the low-temperature part in the turbine component, and sets the above-mentioned temperature difference to the thermal stress permissible temperature Tp.

[0099] FIG. 4 is a block diagram showing a configuration of the control device 260 of the coolant temperature adjustment mechanism 200 in the axial flow turbine 1 according to the embodiment.

[0100] As shown in FIG. 4, the control device 260 includes an input unit 261, a storage unit 262, a calculation unit 263, and an output unit 264.

[0101] The input unit 261 inputs detection signals and other input signals from various detection units. Specifically, the input unit 261 inputs detection signals from the low temperature unit temperature detection unit 240, the cooling medium pressure detection unit 241, the high temperature unit temperature detection unit 250, the turbine internal pressure detection unit 251, etc.

[0102] Other input signals include, for example, an input signal related to a turbine component to be monitored for thermal stress, an input signal related to the end of operation, etc. Note that the other input signals are not limited to these, and include all signals necessary to operate the coolant temperature control mechanism 200.

[0103] The storage unit 262 is configured with a storage medium such as a read-only memory (ROM) or a random access memory (RAM), etc. The storage unit 262 includes a thermal stress allowable temperature storage unit 262a and a valve opening degree storage unit 262b.

[0104] The thermal stress allowable temperature storage unit 262a includes a thermal stress allowable temperature table corresponding to the turbine component. For example, the thermal stress allowable temperature storage unit 262a includes a thermal stress allowable temperature table corresponding to each of the stator blade 50 and the outer shroud 30. For example, the thermal stress allowable temperature table stores a lower limit thermal stress allowable temperature Tpl, an upper limit thermal stress allowable temperature Tpu, and the like.

[0105] The thermal stress allowable temperature table stores the allowable range of the difference (Ta2-Ta1) between the temperature Ta2 of the high temperature part of the turbine component and the temperature Ta1 of the low temperature part of the turbine component under the temperature conditions to which the turbine component is exposed. That is, the allowable range of this temperature difference is the thermal stress allowable temperature Tp. In the allowable range of the temperature difference, the lower limit is the lower limit thermal stress allowable temperature Tpl and the upper limit is the upper limit thermal stress allowable temperature Tpu.

[0106] For example, a hot spot may be located on an exterior surface of a turbine component exposed to the working fluid, and a cold spot may be located on an interior surface exposed to a cooling medium across the wall thickness of the turbine component from the hot spot.

[0107] The allowable range of this temperature difference is set based on, for example, the results of a thermal stress analysis to a range where thermal stress can be suppressed and strength can be maintained. In the thermal stress analysis, the constituent materials and thicknesses of the turbine parts are taken into consideration. Note that the temperatures Ta1 and Ta2 are not actual measured values, but are the temperatures obtained from the thermal stress analysis.

[0108] Furthermore, the flow rate of the cooling medium that cools the turbine components changes depending on the operating conditions of the axial flow turbine 1. This flow rate of the cooling medium can be roughly calculated based on the difference (Pt1-Pt2) between the pressure Pt1 of the cooling medium introduced from the adjustment pipe 230 to the axial flow turbine 1 and the pressure Pt2 of a predetermined space where the cooling medium is introduced to cool the turbine components.

[0109] For example, in the case of the stator vane 50, the pressure Pt2 is the assumed pressure in the cooling passage 51. In the case of the outer shroud 30, the pressure Pt2 is the assumed pressure in the space 31. Note that the pressures Pt1 and Pt2 are not actual measured values, but represent pressures obtained through fluid analysis.

[0110] Furthermore, the range of the pressure difference (Pt1-Pt2) that changes depending on the operating conditions of the axial flow turbine 1 can be divided into predetermined pressure ranges. Therefore, the thermal stress allowable temperature storage unit 262a is provided with a thermal stress allowable temperature table in which the thermal stress allowable temperature Tp is set according to each of the divided pressure ranges. This makes it possible to adjust the temperature difference between the high temperature part and the low temperature part to the optimal thermal stress allowable temperature Tp according to the flow rate of the cooling medium, even if the flow rate of the cooling medium changes depending on the operating conditions of the axial flow turbine 1.

[0111] In the coolant temperature adjustment mechanism 200, the flow rate of the coolant is assumed to be constant until the next change in the flow rate, and the temperature of the coolant is controlled.

[0112] The valve aperture memory unit 262b includes a valve aperture adjustment table for adjusting the difference (Tm2-Tm1) between the temperature Tm2 detected by the high temperature section temperature detection unit 250 and the temperature Tm1 detected by the low temperature section temperature detection unit 240 to within the thermal stress allowable temperature Tp. Specifically, the valve aperture memory unit 262b includes a valve aperture adjustment table for the low temperature side flow rate adjustment valve 211 and the high temperature side flow rate adjustment valve 221 for adjusting the temperature Tm1 so that the temperature difference (Tm2-Tm1) becomes the thermal stress allowable temperature Tp.

[0113] The calculation unit 263 executes various calculation processes using, for example, programs and data (tables) stored in the storage unit 262. The calculation unit 263 includes a differential pressure calculation unit 263a, a temperature determination unit 263b, and a valve opening setting unit 263c.

[0114] The differential pressure calculation unit 263a calculates the difference (Pm1-Pm2) between the pressure Pm1 detected by the cooling medium pressure detection unit 241 and the pressure Pm2 detected by the turbine internal pressure detection unit 251 based on the detection signals from the cooling medium pressure detection unit 241 and the turbine internal pressure detection unit 251.

[0115] The temperature determination unit 263b determines whether the difference (Tm2-Tm1) between the temperature Tm2 detected by the high temperature temperature detection unit 250 and the temperature Tm1 detected by the low temperature temperature detection unit 240 exceeds the upper limit thermal stress allowable temperature Tpu or is below the lower limit thermal stress allowable temperature Tpl based on the detection signals from the low temperature temperature detection unit 240 and the high temperature temperature detection unit 250, the differential pressure calculated by the differential pressure calculation unit 263a, and the data in the thermal stress allowable temperature memory unit 262a.

[0116] Here, the temperature determination unit 263b selects a thermal stress allowable temperature table classified according to the magnitude of the pressure difference based on the differential pressure calculated by the differential pressure calculation unit 263a, and performs the above determination.

[0117] When selecting a thermal stress allowable temperature table, the temperature determination unit 263b selects the thermal stress allowable temperature table related to the turbine component to be monitored for thermal stress, for example, based on an input signal related to that turbine component.

[0118] Based on the determination of the temperature determination unit 263b and the data of the valve opening storage unit 262b, the valve opening setting unit 263c outputs a control signal for controlling the valve opening of the low-temperature side flow rate adjustment valve 211 and the high-temperature side flow rate adjustment valve 221 to the output unit 264. Specifically, the valve opening setting unit 263c outputs a valve opening control signal to the output unit 264 for adjusting the temperature Tm1 so that the temperature difference (Tm2-Tm1) between the temperatures Tm2 and Tm1 becomes the thermal stress allowable temperature Tp.

[0119] The output unit 264 outputs the control signal output from the valve opening degree setting unit 263 c to the low temperature side flow rate adjustment valve 211 and the high temperature side flow rate adjustment valve 221 .

[0120] Here, the processes executed by the control device 260 described above are realized by, for example, a computer device.

[0121] Next, the action of the cooling medium introduced by the second cooling medium introduction mechanism 100B will be described.

[0122] As shown in FIG. 1, the CO 2 The gas is introduced as a first cooling medium (low-temperature cooling medium) from the circulation pipe 360 ​​to the low-temperature side pipe 210. In addition, the CO 2 The gas is introduced from the circulation piping 360 into the high temperature side piping 220 as a second cooling medium (high temperature cooling medium) having a higher temperature than the first cooling medium.

[0123] The low-temperature cooling medium and the high-temperature cooling medium that flow into the adjustment pipe 230 are mixed to become a cooling medium (third cooling medium) that cools the turbine components. Then, the cooling medium for cooling after mixing is introduced from the adjustment pipe 230 into the cooling medium introduction passage 150. The action of the cooling medium introduced into the cooling medium introduction passage 150 is as described above.

[0124] Next, the operation of the cooling medium temperature adjustment mechanism 200 will be described.

[0125] FIG. 5 is a flowchart illustrating the operation of the coolant temperature adjustment mechanism 200 in the axial flow turbine 1 according to the embodiment.

[0126] Here, it is assumed that an input signal related to either the stator vane 50 or the outer shroud 30 is input to the input unit 261 as an input signal related to the turbine component to be monitored for thermal stress. Also, the coolant temperature adjustment mechanism 200 acts based on the input signals from the high temperature section temperature detection unit 250 and the turbine internal pressure detection unit 251 corresponding to the input turbine component.

[0127] Here, when the cooling medium temperature control mechanism 200 is operating, detection signals are constantly input to the input unit 261 from the low temperature detection unit 240, the cooling medium pressure detection unit 241, the high temperature temperature detection unit 250, and the turbine internal pressure detection unit 251.

[0128] As shown in FIG. 5, the differential pressure calculation unit 263a calculates the pressure difference (Pm1-Pm2) between the pressure Pm1 detected by the cooling medium pressure detection unit 241 and the pressure Pm2 detected by the turbine internal pressure detection unit 251 based on detection signals from the cooling medium pressure detection unit 241 and the turbine internal pressure detection unit 251 (step S10).

[0129] Then, the differential pressure calculation unit 263a outputs information related to the calculated differential pressure to the temperature determination unit 263b.

[0130] The temperature determination unit 263b selects a thermal stress allowable temperature table to be referenced based on the differential pressure calculated by the differential pressure calculation unit 263a and the data of the thermal stress allowable temperature storage unit 262a. Furthermore, the temperature determination unit 263b determines whether or not the temperature difference (Tm2-Tm1) between the temperature Tm2 detected by the high temperature temperature detection unit 250 and the temperature Tm1 detected by the low temperature temperature detection unit 240 exceeds the upper limit thermal stress allowable temperature Tpu based on the detection signals from the low temperature section temperature detection unit 240 and the high temperature section temperature detection unit 250 and the selected thermal stress allowable temperature table (step S11).

[0131] When it is determined in step S11 that the temperature difference exceeds the upper limit thermal stress allowable temperature Tpu (Yes in step S11), the temperature determination unit 263b outputs information related to the determination result to the valve opening setting unit 263c.

[0132] The valve aperture setting unit 263c outputs control signals for adjusting each of the low-temperature side flow rate adjustment valve 211 and the high-temperature side flow rate adjustment valve 221 to the output unit 264 based on the judgment result of the temperature judgment unit 263b and the valve aperture adjustment table of the valve aperture storage unit 262b (step S12). Then, the output unit 264 outputs the control signals from the valve aperture setting unit 263c to the low-temperature side flow rate adjustment valve 211 and the high-temperature side flow rate adjustment valve 221 to adjust the valve aperture (step S12).

[0133] In addition, in step S12, the valve opening setting unit 263c outputs a control signal to the output unit 264 to control the low-temperature side flow rate adjustment valve 211 and the high-temperature side flow rate adjustment valve 221 to raise the temperature Tm1 so that the temperature difference (Tm2-Tm1) becomes the thermal stress allowable temperature Tp.

[0134] Here, until the process of step S10 is executed again, the flow rate of the cooling medium is kept constant and the determination is executed based on the thermal stress allowable temperature table selected in step S11. Therefore, specifically, in step S12, control is executed to raise the temperature of the cooling medium while maintaining the flow rate of the cooling medium constant. That is, in step S12, the opening degree of the low-temperature side flow rate adjustment valve 211 is decreased and the opening degree of the high-temperature side flow rate adjustment valve 221 is increased.

[0135] After adjusting the valve opening in step S12, the temperature judgment unit 263b judges whether the temperature difference (Tm2-Tm1) exceeds the upper limit thermal stress allowable temperature Tpu based on the detection signals from the low temperature section temperature detection unit 240 and the high temperature section temperature detection unit 250 and the selected thermal stress allowable temperature table (step S13).

[0136] If it is determined in step S13 that the temperature difference exceeds the upper limit thermal stress allowable temperature Tpu (Yes in step S13), the temperature determination unit 263b outputs information related to the determination result to the valve opening setting unit 263c, and repeats the process of step S12.

[0137] When it is determined in step S13 that the temperature difference does not exceed the upper limit thermal stress allowable temperature Tpu (No in step S13), the process of step S14 is executed.

[0138] If it is determined in step S11 or step S13 that the temperature difference does not exceed the upper limit thermal stress allowable temperature Tpu (No in step S11 or No in step S13), the temperature determination unit 263b determines whether the temperature difference is below the lower limit thermal stress allowable temperature Tpl (step S14).

[0139] If it is determined in step S14 that the temperature difference is not below the lower limit thermal stress allowable temperature Tpl (No in step S14), for example, the temperature determination unit 263b determines whether information related to the end of the action has been input from the input unit 261 (step S15).

[0140] If it is determined in step S15 that information relating to the end has not been input (No in step S15), the process of step S10 is executed.

[0141] If it is determined in step S15 that information relating to the end has been input (Yes in step S15), the temperature determining unit 263b ends the operation of the cooling medium temperature adjustment mechanism 200.

[0142] When it is determined in step S14 that the temperature difference is below the lower limit thermal stress allowable temperature Tpl (Yes in step S14), the temperature determination unit 263b outputs information related to the determination result to the valve opening setting unit 263c.

[0143] The valve aperture setting unit 263c outputs control signals for adjusting each of the low-temperature side flow rate adjustment valve 211 and the high-temperature side flow rate adjustment valve 221 to the output unit 264 based on the judgment result of the temperature judgment unit 263b and the valve aperture adjustment table of the valve aperture storage unit 262b (step S16). Then, the output unit 264 outputs the control signals from the valve aperture setting unit 263c to the low-temperature side flow rate adjustment valve 211 and the high-temperature side flow rate adjustment valve 221 to adjust the valve aperture (step S16).

[0144] In addition, in step S16, the valve opening setting unit 263c outputs a control signal to the output unit 264 to control the low-temperature side flow rate adjustment valve 211 and the high-temperature side flow rate adjustment valve 221 to lower the temperature Tm1 so that the temperature difference (Tm2-Tm1) becomes the thermal stress allowable temperature Tp.

[0145] Specifically, in step S16, control is executed to lower the temperature of the cooling medium while maintaining the flow rate of the cooling medium constant. That is, in step S16, the opening degree of the low-temperature side flow rate adjustment valve 211 is increased and the opening degree of the high-temperature side flow rate adjustment valve 221 is decreased.

[0146] After adjusting the valve opening in step S16, the temperature judgment unit 263b judges whether the temperature difference (Tm2-Tm1) is below the lower limit thermal stress allowable temperature Tpl based on the detection signals from the low temperature section temperature detection unit 240 and the high temperature section temperature detection unit 250 and the selected thermal stress allowable temperature table (step S17).

[0147] If it is determined in step S17 that the temperature difference is below the lower limit thermal stress allowable temperature Tpl (Yes in step S17), the temperature determination unit 263b outputs information related to the determination result to the valve opening setting unit 263c and repeats the process of step S16.

[0148] If it is determined in step S17 that the temperature difference is not below the lower limit thermal stress allowable temperature Tpl (No in step S17), the temperature determination unit 263b determines whether the temperature difference exceeds the upper limit thermal stress allowable temperature Tpu (step S18).

[0149] When it is determined in step S18 that the temperature difference does not exceed the upper limit thermal stress allowable temperature Tpu (No in step S18), for example, the temperature determining unit 263b executes the process of step S15.

[0150] When it is determined in step S18 that the temperature difference exceeds the upper limit thermal stress allowable temperature Tpu (Yes in step S18), the process of step S12 is executed.

[0151] In addition, in the operation of the cooling medium temperature adjustment mechanism 200 described above, if a signal relating to stopping is input to the input unit 261 regardless of the judgment in step S15, for example, the temperature judgment unit 263b terminates the operation of the cooling medium temperature adjustment mechanism 200.

[0152] Here, by the action of the above-mentioned coolant temperature adjustment mechanism 200, for example, the temperature difference (Tm2-Tm1) between the high temperature part and the low temperature part of the turbine component becomes the thermal stress allowable temperature Tp. As a result, the thermal stress generated in the turbine component falls within the range of the allowable thermal stress. Therefore, damage to the turbine component is prevented.

[0153] As described above, according to the axial flow turbine 1 of the embodiment, by providing the second cooling medium introduction mechanism 100B (cooling medium temperature adjustment mechanism 200), it is possible to adjust the temperature of the cooling medium that cools the turbine components.

[0154] This allows the temperature of the low temperature part of the turbine component to be adjusted, and the temperature difference between the high temperature part and the low temperature part (Tm2-Tm1) can be set to the thermal stress allowable temperature Tp. Therefore, the thermal stress generated in the turbine component is suppressed within the range of the allowable thermal stress.

[0155] That is, according to the axial flow turbine 1 of the embodiment, by providing the coolant temperature adjustment mechanism 200, it is possible to adjust the temperature of the coolant in consideration of the thermal stress of the turbine components, thereby adjusting the temperature of the low-temperature parts of the turbine components. This makes it possible to set the temperature difference (Tm2-Tm1) to the thermal stress permissible temperature Tp, and to prevent the turbine components from being damaged by thermal stress.

[0156] In the above-described embodiment, the gas turbine equipment 300 is a supercritical CO 2 Although the turbine facility has been described as an example, the present invention is not limited thereto. The configuration of the second cooling medium introduction mechanism 100B (cooling medium temperature adjustment mechanism 200) in the present embodiment can be applied to, for example, gas turbine power generation facilities, steam turbine power generation facilities, and the like.

[0157] Here, in gas turbine power generation equipment and steam turbine power generation equipment, 2 Even when a pipe equivalent to the circulation pipe 360 ​​in the turbine equipment is not provided, the following configuration can be adopted.

[0158] For example, the working fluid bleed from the turbine or the bleed from the piping system can be used as the first cooling medium (low temperature cooling medium) introduced into the low temperature side piping 210 and the second cooling medium (high temperature cooling medium) introduced into the high temperature side piping 220. Even in this case, the temperature of the second cooling medium introduced into the high temperature side piping 220 is higher than the temperature of the first cooling medium introduced into the low temperature side piping 210.

[0159] According to the embodiment described above, it is possible to adjust the temperature of the cooling medium that cools the turbine components, taking into account thermal stress.

[0160] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0161] 1...axial flow turbine, 10...outer casing, 11, 11a, 11b...inner casing, 12...packing head, 12a...upstream end face, 13...packing head, 14, 31, 49...space, 15, 42, 63...seal fin, 20...turbine rotor, 21...rotor wheel, 22...communication hole, 25, 26, 27, 28...gland seal portion, 29...seal portion, 30...outer shroud, 40...inner shroud, 41, 48...through hole, 45...shield Heat piece, 46...heat shield plate, 47...support portion, 50...stationary blade, 51...cooling passage, 60...rotor blade, 61...shroud segment, 62...implant portion, 62a...downstream end surface, 65...working fluid flow path, 70...exhaust chamber, 71...exhaust pipe, 80...wheel space, 100...cooling medium introduction mechanism, 100A...first cooling medium introduction mechanism, 100B...second cooling medium introduction mechanism, 110...cooling medium introduction pipe, 111, 314, 363...flow control valve, 150...cooling medium introduction Flow path, 151... axial passage, 152... radial passage, 200... cooling medium temperature adjustment mechanism, 210... low temperature side piping, 211... low temperature side flow rate adjustment valve, 220... high temperature side piping, 221... high temperature side flow rate adjustment valve, 230... adjustment piping, 230a... connection portion, 240... low temperature portion temperature detection portion, 241... cooling medium pressure detection portion, 250... high temperature portion temperature detection portion, 251... turbine internal pressure detection portion, 260... control device, 261... input portion, 262... memory portion, 262a... thermal stress tolerance Capacity temperature memory unit, 262b...valve opening memory unit, 263...calculation unit, 263a...differential pressure calculation unit, 263b...temperature determination unit, 263c...valve opening setting unit, 264...output unit, 300...gas turbine equipment, 310...combustor, 311...fuel piping, 312...flow control valve, 313...oxidizer piping, 315...transition piece, 320...generator, 330...regenerative heat exchanger, 340...cooler, 350...compressor, 360...circulation piping, 361...drain pipe, 362...exhaust pipe.

Claims

1. 1. An axial flow turbine comprising turbine components cooled by a cooling medium, a cooling medium introduction mechanism that introduces a third cooling medium into the axial flow turbine as a cooling medium for the turbine component, the third cooling medium being adjusted by mixing a first cooling medium with a second cooling medium having a temperature higher than that of the first cooling medium so that a temperature difference between a high temperature portion and a low temperature portion of the turbine component satisfies a thermal stress allowable temperature; the thermal stress allowable temperature is set according to each range obtained by dividing a pressure difference (Pt1-Pt2) between an assumed pressure (Pt1) of the third cooling medium introduced into the axial flow turbine and an assumed pressure (Pt2) of a space into which the third cooling medium is introduced to cool the turbine components, into predetermined pressure ranges; An axial flow turbine, characterized in that the thermal stress allowable temperature is selected based on a pressure difference (Pm1-Pm2) between a detected pressure (Pm1) of the third cooling medium introduced into the axial flow turbine and a detected pressure (Pm2) of a space into which the third cooling medium is introduced to cool the turbine components.

2. the cooling medium introduction mechanism includes a cooling medium temperature adjustment mechanism that adjusts a temperature of the third cooling medium so that the temperature difference satisfies the thermal stress allowable temperature; The cooling medium temperature adjustment mechanism includes: a low-temperature side pipe for introducing the first cooling medium; a high temperature side pipe for introducing the second cooling medium; an adjustment pipe connected to the low-temperature side pipe and the high-temperature side pipe, for introducing the third cooling medium, which is a mixture of the first cooling medium and the second cooling medium, as a cooling medium for the turbine component; 2. The axial flow turbine according to claim 1, further comprising:

3. a low-temperature side flow rate adjustment valve provided in the low-temperature side piping and adjusting a flow rate of the first cooling medium introduced into the adjustment piping; a high-temperature side flow rate control valve provided in the high-temperature side piping and controlling a flow rate of the second cooling medium introduced into the control piping; a control device that adjusts the temperature of the third cooling medium by controlling the low-temperature side flow rate adjustment valve and the high-temperature side flow rate adjustment valve so that the temperature difference satisfies the thermal stress allowable temperature; 3. The axial flow turbine according to claim 2, further comprising:

4. a first temperature detector configured to detect a temperature of a low-temperature portion of the turbine component that is cooled by the third cooling medium; a second temperature detector configured to detect a temperature associated with a high temperature portion of the turbine component; Equipped with The control device includes:

4. The axial flow turbine according to claim 3, characterized in that the temperature difference, which is the difference between the temperature detected by the second temperature detection unit and the temperature detected by the first temperature detection unit, is compared with the thermal stress allowable temperature to control the low-temperature side flow control valve and the high-temperature side flow control valve.

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