JP2003307136A - Closed cooling gas turbine and method for cooling high temperature part of gas turbine - Google Patents

Abstract

(57) [Summary] [Problem] Without reducing the thermal efficiency of a gas turbine,
It suppresses uneven combustion state and uneven deformation of the combustor casing. A closed-cooling gas turbine provided with a combustor that burns a compressed working fluid and fuel, and a cooling system that cools a high-temperature portion of the gas turbine, wherein the closed-cooling type gas turbine includes a cooling fluid that cools the high-temperature portion. And recovering a portion of the working fluid that has cooled the high-temperature portion upstream of the cooling system. [Effect] A highly reliable closed cooling gas turbine can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a closed cooling type gas turbine and a method for cooling a high temperature part of a gas turbine.

[0002]

2. Description of the Related Art Compressor outlet air is extracted and cooled by a cooler, the cooled air is pressurized by a compressor to cool a high temperature part of a gas turbine, and the cooled air is recovered as combustion air in a combustor. Regarding the closed cooling type gas turbine that performs the above, Japanese Patent Laid-Open Nos. 10-196316 and 2001-1406
No. 59, etc.

[0003]

As the combustion temperature rises and the thermal efficiency increases, the cooling of the first-stage stator vanes located at the high temperature part of the gas turbine, especially upstream of the combustion gas, is strengthened to keep the metal temperature below the allowable value. It is becoming necessary to maintain. An effective way to enhance cooling is to increase the flow rate of the refrigerant. However, when the refrigerant flow rate is increased, the amount of temperature increase of the refrigerant after cooling is also reduced, and the degree of improvement in thermal efficiency due to recovery in the combustor is also reduced. When the temperature of the refrigerant is lowered in advance by using the precooler, the temperature of the refrigerant recovered after cooling the high temperature part may be lower than the temperature of the combustor compartment. When this low-temperature refrigerant is collected in the combustor, the combustion temperature is lowered, so that the thermal efficiency of the gas turbine is lowered.

Further, the refrigerant recovered at a temperature lower than the temperature of the combustor compartment causes the working fluid temperature in the combustor compartment to become non-uniform, making the combustion state unstable, and the metal temperature in the combustor compartment being non-uniform. Therefore, the combustor casing may be deformed unevenly and the rotor and the casing may come into contact with each other.

Further, when cooling the moving blades as a high temperature part of the gas turbine, in order to cool the moving blades, a passage for supplying a refrigerant to the inside of the rotor and a passage for taking out the cooled temperature-increased refrigerant from the rotor are provided. There is a need. In the rotor, there are a low temperature field for the refrigerant supply passage and a high temperature field for the refrigerant recovery passage,
If thermal stress is generated due to the rotor temperature distribution, or if temperature unevenness occurs in the circumferential direction, rotor shaft vibration may occur due to uneven deformation of the rotor. In order to suppress these thermal stress, vibration, etc., it is desirable to reduce the amount of temperature rise of the recovered refrigerant. However, if the temperature of the refrigerant recovered from the moving blades is reduced and the refrigerant is recovered in the combustor casing, the combustion temperature is lowered, and the thermal efficiency of the gas turbine is reduced. There is also a problem that the temperature of the combustor compartment is not uniform.

An object of the present invention is to provide a highly reliable closed-cooling type gas turbine and a high temperature gas turbine which suppresses non-uniform combustion conditions and non-uniform deformation of the combustor casing without lowering the thermal efficiency of the gas turbine. It is to provide a partial cooling method.

[0007]

SUMMARY OF THE INVENTION The present invention is a closed cooling gas turbine comprising a combustor for combusting a compressed working fluid and fuel, and a cooling system for cooling the hot part of the gas turbine. A part of the working fluid that has cooled the high temperature part is recovered in the combustor, and a part of the working fluid that has cooled the high temperature part is recovered to the upstream side of the cooling system.

[0008]

Various working fluids are conceivable, such as air, steam, a mixture of air and steam, and nitrogen. In this embodiment, the working fluid will be described as air.

(Embodiment 1) An embodiment of the present invention will be described with reference to FIG. FIG. 1 shows a system diagram of a closed cooling type gas turbine which is an embodiment of the present invention. This gas turbine mainly includes a compressor 1 that compresses a working fluid, a combustor 2 that burns the compressed working fluid and fuel, and a turbine 3 that expands the burned high-temperature high-pressure working fluid to generate power. ing. Next, the drive system of the gas turbine will be described.

In the compressor 1, the atmospheric air 4 is compressed,
It reaches the compressor outlet 5. Here, the passage from the compressor outlet 5 to the combustor 2 is the combustor casing 6. The high-temperature, high-pressure air that is the compressed working fluid passes through the combustor casing 6 and is supplied to the combustor 2.

In the combustor 2, the combustion gas 8 is generated by the high-temperature high-pressure air supplied from the combustor casing 6 and the fuel 7 supplied from another system. Then, the combustion gas 8 is supplied to the turbine 3.

In the turbine 3, power is generated by the supplied combustion gas 8 to drive the compressor 1 and the generator 9.
Combustion gas 8 that generated power in turbine 3 is exhaust gas 10
As emitted from the gas turbine.

Next, the cooling system will be described. Here, the fluid passage from the combustor casing 6 to the high temperature portion 11 requiring cooling is referred to as a first passage 12, and the fluid passage from the outlet of the high temperature portion 11 to the combustor casing 6 is referred to as a second passage 13. The fluid passage extending from the outlet of the high temperature portion 11 to the first passage is referred to as a third passage 14.

In this embodiment, the air in the combustor casing 6 is extracted and used in the first passage 12 as a refrigerant for cooling the high temperature portion 11 of the gas turbine. The extracted air is supplied to the precooler 15 to lower the temperature of the cooling air. The air cooled by the precooler 15 is boosted by the boost compressor 16 which is separate from the compressor 1. Then, the pressurized air is supplied to the high temperature portion 11 of the gas turbine.
To cool the high temperature part 11.

The air that has cooled the high temperature portion 11 of the gas turbine is recovered in two systems, a second passage and a third passage. In the first recovery system, the cooled air is supplied to the combustor casing 6 through the second passage 13 and can be used as combustion air.

On the other hand, in the second recovery system, the cooled air is supplied to the first passage 12 through the third passage 14.

Thus, two systems for collecting the air after cooling the high temperature portion 11 are provided, one of which is connected to the combustor casing 6.
Since the other side is connected to the compressor 1 outlet side of the cooling system, it is possible to obtain a configuration in which it is recovered at an appropriate location based on the air temperature after cooling.

It is desirable that the high temperature portion to be cooled is divided into a portion where cooling is to be strengthened and a portion where cooling is not to be strengthened, and cooling air recovery from the portion where cooling is to be strengthened is connected to the compressor 1 outlet side of the cooling system. . Then, it is desirable to connect the recovery of the cooling air from the portion that does not enhance the cooling to the combustor casing 6.

The high temperature part to be cooled is divided into two parts, and the cooling air having an appropriate temperature is recovered in the combustor casing 6 based on the temperature of the cooling air recovered from each part. It is desirable to connect cooling air, which is collected on the side of No. 6 and supplied to the combustor casing 6, to the compressor 1 outlet side of the cooling system so as to cause a temperature drop.

As the combustion temperature of the gas turbine rises, it is necessary to strengthen the cooling of the high temperature portion 11a on the upstream side of the turbine even in the high temperature portion 11. Gas turbine combustion temperature is 150
When the temperature reaches 0 ° C, the optimum pressure ratio of the closed cooling type gas turbine reaches about 25.
It reaches around 00 ° C.

In order to effectively cool the high temperature part of the gas turbine, the temperature is reduced by the precooler 15, and the boost compressor 16 preliminarily boosts the pressure to cover the pressure loss due to the cooling of the high temperature part. The high temperature portion 11a on the upstream side is exposed to a high temperature gas of 1500 ° C. at the maximum, and therefore a large amount of cooling air is required. If a large amount of air is used, the amount of increase in the temperature of the cooling air at the outlet of the high temperature portion 11a also decreases, and the air temperature at the outlet of the compressor 50
It may be lower than 0 ° C. If the outlet air of the high temperature portion 11a is collected in the combustor casing 6, the combustion temperature will be lowered and the thermal efficiency of the gas turbine will be lowered. Even if the fuel 7 is increased so as not to lower the combustion temperature, the thermal efficiency is also reduced.

Therefore, in the present embodiment, the air that has cooled the high temperature portion 11a is collected in the first passage 12 through the third passage 14. Thus, the high temperature part 1 on the upstream side of the turbine
Since the air after cooling 1a is not collected in the combustor casing 6 but is connected to the compressor 1 outlet side which is the upstream side of the cooling system,
Even if the cooling capacity of the high temperature part 11a is increased, the combustion efficiency of the combustor casing 6 is not lowered and the thermal efficiency is not deteriorated.

Further, it is desirable to connect the third passage upstream of the precooler 15 as described above. As a result, the air temperature at the inlet of the precooler 15 is adjusted to 50
It can be lowered from 0 ° C. Since the air temperature at the inlet of the precooler 15 is reduced, the amount of heat radiation in the precooler 15 can be reduced and the thermal efficiency can be increased.

On the other hand, the air that has cooled the high temperature portion 11b on the downstream side can be heated to a temperature higher than the air that has cooled the high temperature portion 11a, so it is collected in the combustor casing 6 and used as combustion air. The amount of heat obtained by cooling the high temperature portion 11b is recovered in the combustor 2, so that the consumption of the fuel 7 is suppressed and the efficiency is improved.

A closed cooling type gas turbine equipped with a combustor 2 for burning a compressed working fluid and fuel, and a cooling system for cooling the high temperature portion 11 of the gas turbine. Collect a part in the combustor 2,
Moreover, since a part of the working fluid that has cooled the high temperature part 11 is configured to be recovered on the upstream side of the cooling system, it is possible to obtain a structure in which it is recovered at an appropriate location based on the air temperature after cooling.

(Embodiment 2) An embodiment of the present invention will be described with reference to FIG. The difference from the embodiment of FIG. 1 is that the boost compressor 16 and the precooler 15 are arranged on the first passage 12 along the flow.
It is being installed in the reverse order.

The air that has cooled the upstream high temperature section 11a passes through the third passage 14 and is collected on the first passage 12 upstream of the boost compressor 16.

When the combustion temperature reaches about 1500 ° C., FIG.
As described in the above embodiment, the temperature of the air recovered from the high temperature portion 11a becomes lower than the compressor outlet temperature, and the boost compressor 16 inlet air temperature can be lowered.

Therefore, the power of the boost compressor 16 can be reduced, and the thermal efficiency can be improved. Further, since the temperature at the outlet of the boost compressor 16 is also lowered, the amount of heat radiation in the precooler 15 is also reduced, so that the thermal efficiency is similarly improved.

(Embodiment 3) An embodiment of the present invention will be described with reference to FIG. First stage wheel 20, Second stage wheel 2
1, a third stage wheel 22, a fourth stage wheel 23, and a first stage rotor blade 24 and a second stage rotor blade 2 located on the outer peripheral portions thereof.
5, a third stage rotor blade 26, a fourth stage rotor blade 27, and spacers 28, 29, 30 located on the side surfaces of the wheel, and a distant piece 31, which is connected to the compressor side, a fourth stage
The turbine rotor is constituted by the stub shaft 32 located on the side surface of the step wheel 23.

The distant piece 31, the first-stage wheel 20 to the fourth-stage wheel 23, the spacers 28, 29, 30 located between them, and the stub shaft 32.
Are firmly connected by stacking bolts 33 provided on the joining surfaces of the wheel and the spacer.

The combustor 2 is fixed to a combustor casing 40, and has a first stage vane 41, a second stage vane 42, and a third stage vane 4.
The third and fourth stage vanes 44 are attached to the turbine casing 45. The combustor casing 6 includes a combustor casing 40.
And the turbine casing 45 and the inner casing 46, the air in the combustor casing 6 becomes combustion gas by the fuel 7 in the combustor 2, and the first stage vane 41 to the fourth stage rotor blade 27
Is flowing in the direction of.

The cooling air for the gas turbine is supplied to the combustor casing 6
The air is extracted from the first passage 12, the temperature is reduced by the precooler 15 on the first passage 12, the pressure is increased by the boost compressor 16, and it is used for cooling the stationary blades and the moving blades, which are high temperature portions.

Among the stationary blades, the first-stage stationary blade 41 supplies the cooled air through the third passage 14 to the upstream of the precooler 15 in the first passage 12. The second stage vanes 42 further supply the cooled air to the third stage vanes 43, and recover the cooled air to the combustor casing 6 through the second passage 13a.

As for the moving blades, the air discharged from the boost compressor 16 is supplied to the first-stage moving blades 24 and the second-stage moving blades 25 through the rotor internal passage through the center hole of the stub shaft 32. . The third stage rotor blades 26 are further cooled by the air after the second stage rotor blades 25 are cooled. The air that has cooled the first-stage rotor blades 24 and the third-stage rotor blades 26 is recovered in the combustor casing 6 through the second passage 13a in the rotor.

The first stage vane 41 is located immediately after the combustor 2 and therefore is exposed to the highest temperature. When the combustion temperature reaches about 1500 ° C., a large amount of cooling air is required to keep the first stage vane 41 within the allowable temperature, and the air temperature at the outlet of the first stage vane 41 is lower than the air temperature in the combustor casing 6. Become. If the air after cooling the first-stage stationary blades 41 is collected in the combustor casing 6, the combustion temperature will be lowered and the thermal efficiency of the gas turbine will be lowered. Even if the fuel 7 is increased so as not to lower the combustion temperature, the thermal efficiency is also reduced. Furthermore, the cooling air recovered at a temperature lower than the temperature of the combustor casing 6 makes the temperature of the air in the combustor casing 6 non-uniform to make the combustion state unstable, or the combustor casing 40 and the turbine casing 45. The metal temperature of the inner casing 46 may become non-uniform, resulting in non-uniform casing deformation and contact between the rotor and the casing.

Therefore, in this embodiment, the air that has cooled the first stage vane 41 passes through the third passage 14 and the first passage 12
Have been collected. In addition, the third passage is connected to the precooler 15
Since the air temperature at the inlet of the precooler 15 can be lowered from 500 ° C. by communicating with the upstream of the air conditioner, it is possible to reduce the amount of temperature decrease in the precooler 15 and reduce the amount of heat radiation, thereby increasing the thermal efficiency. Become. Further, it is possible to suppress uneven deformation of the casing due to uneven temperature.

(Embodiment 4) An embodiment of the present invention will be described with reference to FIG. The difference from the embodiment of FIG. 3 is that the air after cooling the first stage rotor blades 24 is collected in the combustor casing 6 through the second passage 13c, and the air after cooling the rotor blades is returned to the third passage. 1
The point is that the gas is collected at the inlet of the precooler 15 through the first passage 12 through the No. 4 passage.

In order to cool the moving blades, a passage 50 for supplying air to the inside of the rotor and a passage 51 for taking out the cooled air having an increased temperature from the rotor are provided. Therefore, a low temperature field of the refrigerant supply passage and a high temperature field of the refrigerant recovery passage are created in the rotor, and when thermal stress due to the rotor temperature distribution occurs or temperature unevenness in the circumferential direction occurs, rotor shaft vibration is caused by uneven deformation of the rotor. May occur. In order to suppress these thermal stresses, vibrations, etc., it is desirable to reduce the amount of temperature rise of the recovered air.

However, if the temperature of the air recovered from the moving blades is lowered and the air is recovered in the combustor casing 6, the combustion temperature is lowered and the thermal efficiency of the gas turbine is lowered. Furthermore, the air recovered at a temperature lower than the temperature of the combustor casing 6 makes the working fluid temperature in the combustor casing ununiform to make the combustion state unstable, or the metal temperature in the combustor casing becomes uneven. There is also a risk of non-uniform deformation of the combustor casing causing contact between the rotor and the casing. Therefore, as shown in this figure, the air after cooling the moving blades is collected at the inlet of the precooler 15 in the first passage 12 through the third passage 14.

By connecting the third passage upstream of the precooler 15, the air temperature at the inlet of the precooler 15 can be lowered from 500 ° C. Therefore, the precooler 1
Therefore, the amount of heat dissipation can be reduced by reducing the amount of temperature decrease at 5 and the thermal efficiency can be increased. Further, it is possible to suppress uneven deformation of the casing due to uneven temperature.

(Embodiment 5) An embodiment of the present invention will be described with reference to FIG. The difference from the embodiment of FIG. 3 is that as the first stage stationary blade 41 cooling, steam from another steam generating source 101 is supplied,
The point is that the steam after cooling the first stage stationary blades 41 is taken out from the gas turbine and is supplied to the facility 102 different from the gas turbine. Since the first-stage stationary blade 41 is located immediately after the combustor, it is exposed to the highest temperature among the stationary blades and the moving blades. If the first-stage stationary vanes 41 are cooled by the air from the combustor casing 6, a large amount of air is required, and the temperature rise amount of the recovered air is correspondingly small. If the temperature of the recovered air becomes lower than the temperature of the air in the combustor casing 6, the efficiency will decrease.

In this embodiment, since the first-stage stationary vane 41 recovery passage is not communicated with the combustor casing 6, the air temperature in the combustor casing 6 is not lowered, so that the efficiency reduction is suppressed.
In addition, the air recovered at a temperature lower than the temperature of the combustor compartment 6 makes the air temperature in the combustor compartment inhomogeneous to make the combustion state unstable, or the metal temperature in the combustor compartment becomes nonuniform. There is less risk that the combustor casing will be deformed and the rotor and casing will come into contact with each other.

If all the stationary blades and moving blades that need to be cooled are cooled with steam, the total flow rate increases, so the equipment for securing the steam source becomes large and the cost becomes high. Further, when the rotor blade is cooled with steam, the steam passes through the rotor in which the rotor blade is implanted, and therefore, there is a possibility that dew condensation occurs when the rotor temperature at the time of startup does not rise. Condensation may cause imbalance of the rotor and cause excessive shaft vibration. Thus, in consideration of cost and reliability, it is desirable to cool with air. However, with respect to the first-stage stationary blade that is exposed to the highest temperature and has a high heat load, it consumes a large amount when cooled with air, and rather than collecting the cooled air having a low temperature in the combustor casing, this embodiment It is advisable to use steam with excellent cooling performance as shown in.

If only the first stage vanes are used, the cost increase due to the increase of steam equipment can be minimized, and the dew condensation at the time of start-up is also a static pair, so there is no vibration or problem. Further, even if water is used as the refrigerant of the first stage vane 41, the same effect can be obtained.

In the above embodiment, the cooled air is collected upstream of the boost compressor on the first passage.
When the combustion temperature reaches about 1500 ° C., the temperature of the air recovered from the high temperature portion becomes lower than the compressor outlet temperature, and the boost compressor inlet air temperature can be lowered. Therefore, the power of the boost compressor can be reduced, and the thermal efficiency can be improved. Further, since the boost compressor outlet temperature also decreases, the amount of heat released by the precooler also decreases, so that the thermal efficiency similarly improves.

Further, according to the present embodiment, the cooling air recovered at a temperature lower than the temperature of the combustor compartment is not recovered in the combustor compartment, so that the air temperature in the combustor compartment is made uneven and the combustion is performed. It does not destabilize the state.

Further, the metal temperatures of the combustor casing, the turbine casing, and the inner casing are not made nonuniform, and the possibility of contact between the rotor and the casing due to deformation of the casing is reduced.

[0049]

According to the present invention, there is provided a highly reliable closed cooling type gas turbine and a highly reliable closed cooling type gas turbine which suppresses non-uniform combustion state and non-uniform deformation of the combustor casing without lowering the thermal efficiency of the gas turbine. A high temperature part cooling method can be provided.

[Brief description of drawings]

FIG. 1 is a system diagram of a closed cooling gas turbine according to an embodiment of the present invention.

FIG. 2 is a system diagram of a closed cooling type gas turbine according to an embodiment of the present invention.

FIG. 3 is a sectional view and a system diagram of a closed cooling gas turbine according to an embodiment of the present invention.

FIG. 4 is a sectional view and a system diagram of a closed cooling type gas turbine according to an embodiment of the present invention.

FIG. 5 is a sectional view and a system diagram of a closed cooling type gas turbine according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Compressor, 2 ... Combustor, 3 ... Turbine, 4 ... Atmosphere air, 5 ... Compressor outlet, 6 ... Combustor compartment, 7 ... Fuel, 8 ...
Combustion gas, 9 ... Generator, 10 ... Exhaust gas, 11 ... High temperature part,
12 ... 1st passage, 13 ... 2nd passage, 14 ... 3rd passage, 15 ... Precooler, 16 ... Boost compressor, 20
... 1st stage wheel, 21 ... 2nd stage wheel, 22 ... 3rd stage
Stage wheel, 23 ... Fourth stage wheel, 24 ... First stage moving blade, 25 ... Second stage moving blade, 26 ... Third stage moving blade, 27 ... Fourth
Stage blades, 28, 29, 30 ... Spacers, 31 ... Distant pieces, 32 ... Stub shafts, 33 ... Stacking bolts, 40 ... Combustor casing, 41 ... First stage vanes, 42 ... Second stage vanes, 43 ... Third Stella vane, 44 ... 4th
Stage vanes, 45 ... Turbine casing.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Nobuaki Kizuka             2-12-1 Omika-cho, Hitachi-shi, Ibaraki Prefecture             Ceremony Company Hitachi, Ltd. (72) Inventor Kazunori Yamanaka             2-12-1 Omika-cho, Hitachi-shi, Ibaraki Prefecture             Ceremony Company Hitachi, Ltd. (72) Inventor Tsuyoshi Takano             2-12-1 Omika-cho, Hitachi-shi, Ibaraki Prefecture             Ceremony Company Hitachi, Ltd. F term (reference) 3G002 AB03 BB04 BB05 CA10 CB01                       FB04 GA08 GB01

Claims (8)

[Claims] 1. A closed cooling gas turbine comprising a combustor for combusting a compressed working fluid and fuel, and a cooling system for cooling a high temperature portion of a gas turbine. A closed cooling gas turbine configured to recover a part of the working fluid that has cooled the high temperature part to an upstream side of the cooling system. 2. A compressor for compressing a working fluid, a combustor for burning the compressed working fluid and fuel, and a turbine for expanding the burned high-temperature and high-pressure working fluid to generate power. A first passage extending from a combustor casing located in a passage leading to the combustor to a high temperature portion requiring cooling, a second passage extending from the high temperature portion outlet to the combustor casing, and a second passage extending from the high temperature portion outlet. A closed cooling gas turbine having a third passage leading to the first passage. 3. The closed cooling gas turbine according to claim 2, wherein the first passage has a precooler for lowering the temperature of the refrigerant in advance along the flow of the refrigerant, and a compressor for compressing the refrigerant. And a compressor separately installed from the compressor, and the third passage communicates with the upstream of the precooler located in the middle of the first passage. Turbine. 4. The closed cooling gas turbine according to claim 2, wherein the first passage is provided with a compressor separate from the compressor for compressing the refrigerant along the flow of the refrigerant. , A precooler for lowering the temperature of the refrigerant in advance, and the third passage communicates with the upstream side of the separately-installed compressor located in the middle of the first passage. Gas turbine. 5. The closed cooling type gas turbine according to any one of claims 2 to 4, wherein the refrigerant recovered in the third passage is obtained by cooling the turbine first stage stationary blade or turbine moving blade. Closed cooling gas turbine configured. 6. A compressor for compressing a working fluid, a combustor for combusting the compressed working fluid and fuel, a turbine for expanding the burned high-temperature and high-pressure working fluid to generate power, and a high-temperature part requiring cooling. A first passage extending from the combustor casing located in the passage extending from the compressor to the combustor to the high temperature portion; a second passage extending from the high temperature outlet to the combustor casing; A closed cooling type gas turbine having a third passage extending from a high temperature portion outlet to a first passage, wherein a turbine first stage stationary blade is provided as a high temperature portion requiring cooling in addition to the high temperature portion, and the first stage stationary blade is cooled. A closed-cooling gas turbine, wherein steam from another steam generating source is supplied to the gas turbine, and the steam after cooling the first-stage stationary blades is taken out from the gas turbine. 7. A compressor for compressing a working fluid, a combustor for combusting the compressed working fluid and fuel, a turbine for expanding the burned high-temperature and high-pressure working fluid to generate power, and a high-temperature portion requiring cooling. A first passage extending from the combustor casing located in the passage extending from the compressor to the combustor to the high temperature portion; a second passage extending from the high temperature outlet to the combustor casing; A closed cooling type gas turbine having a third passage extending from a high temperature portion outlet to a first passage, wherein a turbine first stage stationary blade is provided as a high temperature portion requiring cooling in addition to the high temperature portion, and the first stage stationary blade is cooled. A cooling water from another water supply source, and the cooling water after cooling the first stage stationary blades is taken out from the gas turbine. 8. A method for cooling a high temperature part of a gas turbine, comprising a combustor for combusting a compressed working fluid and fuel, comprising cooling one of the high temperature part of the gas turbine and cooling the high temperature part. A method for cooling a high temperature part of a gas turbine, wherein a part of the working fluid that has cooled the high temperature part is recovered upstream of a cooling system.