JPH0710439U - Gas turbine nozzle cooling device - Google Patents

Abstract

(57) [Summary] [Objective] In a gas turbine engine, the amount and temperature of cooling air can be arbitrarily changed to improve engine efficiency. A branch hole 8a for taking out cooling air from the inside of the engine to the outside, a cooling inflow hole 1b for injecting the cooling air from the outside to the inside and ejecting it to the high-pressure nozzle 13, communication pipes 23 and 27, and a communication passage. A control device 26 for adjusting the flow rate and temperature of the cooling medium according to the engine load and a switching device for the cooling medium are interposed in the passage, and the cooling medium can be adjusted / switched outside the engine casing.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a cooling device for a high pressure nozzle of a gas turbine engine.

[0002]

[Prior art]

 A conventional gas turbine engine is equipped with a centrifugal compressor.Combustion gas produced by compressing air by this centrifugal compressor and sending it to a combustor through a heat exchanger, mixing it with fuel and burning it. Was sent to the high pressure nozzle to drive the moving blade.

[0003]

[Problems to be solved by the device]

 In a conventional gas turbine engine, part of the air that exited the compressor was sent as cooling air to the cooling location through a passage inside the engine, but the temperature of the cooling air is approximately the same as the temperature at the compressor outlet. However, the amount was determined by the passage diameter and compressor outlet pressure, so it was difficult to change. Therefore, the present invention seeks to improve engine efficiency by allowing the amount and temperature of cooling air to be arbitrarily changed.

[0004]

[Means for Solving the Problems]

 The present invention is configured as follows in order to solve the above problems. That is, in the gas turbine engine, a passage for taking out the cooling air from the inside of the engine to the outside and a passage for injecting the cooling air from the outside to the inside and ejecting it to the high pressure nozzle are provided, and the cooling medium is provided in the passage according to the engine load. It is configured so that the cooling medium can be adjusted / switched outside the engine casing by interposing a control device for controlling the flow rate and temperature of the cooling medium and a switching device for the cooling medium.

[0005]

[Action]

 By using such means, the air compressed by the impeller 5 is branched before being sent to the combustor from the outlet passage 2, a part of it is sent to the branch hole 8a, and the flow rate is adjusted by the valve 25. The control box 26 to adjust the temperature, or the valve 25 is closed and the valve 30 is opened to send steam to the control box 26, and the flow rate and temperature are adjusted according to the load detected by the sensor 29. Then, it is sent to the cooling inflow hole 1b of the engine and is jetted to the high pressure nozzle 13 through the communication pipe or the communication hole to be cooled.

[0006]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a compressor and a turbine portion of a gas turbine engine, FIG. 2 is a block diagram of a cooling portion, FIG. 3 is a block diagram showing another embodiment of the same, and FIG. 4 shows a configuration for releasing back pressure of an impeller. A sectional view and FIG. 5 are enlarged sectional views of the outer peripheral end of the impeller.

In FIG. 1, an inner housing 4 is fixed to the inside of a housing 1 of a compressor, and an axial end surface of the inner housing 4 is provided with compressed air between a wall surface of the inner housing 4 and a guide plate 3. An outlet passage 2 is formed, an impeller 5 is installed in an inner housing 4 and is rotatably supported by a bearing, and a peripheral end portion of the impeller 5 is arranged to face an inlet portion of the outlet passage 2. .

A leg 20 is fixed to the outer peripheral end of the guide plate 3 with a bolt 6, and the other end of the leg 20 is fixed to a stay 21 by bolts or welding, and the base of the stay 21 is a scroll 7. A heat shield 22 is fixed together with the legs 20 on the upper surface of the stay 21, and the heat shield 22 dissipates heat from the scroll 7, thereby allowing a cooling communication pipe 23, a lubricating oil pipe, and a bearing to be described later. The scroll 7 and the heat shield 22 are integrally configured so that the heat shield 22 acts as a reinforcing member of the scroll 7, It also prevents deformation of 7 and prevents leaks, etc. to increase efficiency and reduce the number of parts.

The outer peripheral portion of the scroll 7 is covered with a scroll housing 8 joined at the outer end portion of the compressor housing 1, and a containment ring 9 attached to the inner end portion of the scroll housing 8 is The inner peripheral surface of the scroll 7 is covered from the inside. An outlet 10 at the inner end of the scroll 7 is opened in the axial direction on the side opposite to the impeller 5, and a support fixed to the inner end of the guide plate 3 at the radially inner side of the outlet 10. A disk 12 is fixed to the axial end surface of the member 11, and a high pressure nozzle 13 is attached to the outer peripheral portion of the disk 12 so as to face the scroll outlet 10. Further, a moving blade 14 is arranged on the outlet side of the high pressure nozzle 13.

The compressed air that is sent radially outward by the rotation of the impeller 5 is sent to the outlet passage 2 described above, but there is a slight gap between the outer peripheral end of the impeller 5 and the guide plate 3, A part of the compressed air reaches the back surface of the impeller through this gap, and the pressure thereof causes thrust force in the axial direction. Since this thrust force damages the bearings of the rotor and shortens the life of the rotor, a labyrinth seal 5a is formed at the outer peripheral end of the impeller 5 to prevent air from flowing around the back surface of the impeller, as shown in FIG.

Further, since the labyrinth seal 5a alone cannot sufficiently seal, an impeller seal land inner 5b is formed between the impeller shaft portion on the shaft side and the guide plate 3 as shown in FIG. The guide plate 3 in front of the impeller seal land inner 5b is provided with an air vent hole 3a, and the housing 1 is also provided with an air vent hole 1a so that they are communicated with each other by a communication pipe 24. The compressed air that has entered between the impeller shaft and the guide plate 3 is discharged into the atmosphere, and the pressure on the back of the impeller does not rise with a small number of labyrinth seal steps, thus extending the life of the bearing. .

Then, as shown in FIG. 1, the compressed air sent from the outlet passage 2 is sent to a combustor (not shown) from between the outer periphery of the scroll 7 and the inner surface of the scroll housing 8, and the fuel is mixed with the fuel in the combustor. The high-pressure gas generated by mixing and burning passes through the scroll 7 and is ejected from the outlet 10 to the moving blade 14 side through the high-pressure nozzle 13 to rotate the moving blade 14 at high speed to drive the output shaft. Then, the gas that has rotated the moving blade 14 is discharged rearward of the shaft.

In order to cool the high pressure nozzle 13, which is an essential part of the present invention, a branch hole 8a is formed in the scroll housing 8 on the outer peripheral end side of the guide plate 3, and the valve 25 and the control shown in FIG. It is configured to communicate with the cooling inflow hole 1b formed in the housing 1 via the box 26, and the other end of the cooling inflow hole 1b is connected to the guide plate 3 via the cooling communication pipes 27 and 23. Compressed air is blown onto the high-pressure nozzle 13 via the passage 3b, the communication passage 11a of the support member 11, and the communication passage 12a of the disk 12 for cooling.

As shown in FIG. 2, the valve 25 is an electromagnetic valve, and a control box 26 adjusts the opening and closing and the throttle of the valve. The control box 26 detects the engine load by a sensor 29. , Has a control circuit and a temperature adjusting member for adjusting the temperature of the air sent according to the load, and the temperature adjusting member raises the temperature with a heater or the like, or the temperature with a fan or the like. Is adjusted so that the temperature becomes appropriate, and the flow rate thereof is also adjusted by the operation of the valve 25.

Further, the medium for cooling the high-pressure nozzle 13 is not limited to air, but may be, for example, steam. As shown in FIG. 2 so that the temperature can be controlled by steam, the valve 25 is controlled to be closed and the valve 30 is controlled to be opened so that the temperature and flow rate of the steam can be adjusted according to the engine load detected by the sensor 29. It can also be configured to adjust.

[0016]

[Effect of device]

 Since the present invention is configured as described above, the following effects can be obtained. That is, the cooling air taken out from the inside of the engine can be adjusted to the optimum temperature and amount according to the engine load outside the engine, and the adjusted air is injected to the high pressure nozzle. The engine output could be improved more than before without significantly reducing the engine efficiency. Also, since the cooling medium can be changed by switching the valve, it can be selected according to the application and specifications, and the cooling efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a compressor and a turbine section of a gas turbine engine.

FIG. 2 is a block diagram of a cooling unit.

FIG. 3 is a block diagram showing another embodiment of the same.

FIG. 4 is a sectional view showing a configuration for releasing back pressure of the impeller.

FIG. 5 is an enlarged cross-sectional view of the outer peripheral edge of the impeller.

[Explanation of symbols]

 1 Housing 1b Cooling Inflow Hole 8 Scroll Housing 8a Branch Hole 13 High Pressure Nozzle 25/30 Valve 26 Control Box 29 Sensor

Claims (1)

[Scope of utility model registration request] 1. A gas turbine engine is provided with a passage for taking out cooling air from the inside of the engine to the outside, and a passage for injecting cooling air from the outside to the inside to eject the cooling air to a high-pressure nozzle, and the passage is adapted to an engine load. A cooling device for a gas turbine nozzle, wherein an adjusting device for adjusting the flow rate and temperature of the cooling medium and a switching device for the cooling medium are interposed so that the cooling medium can be adjusted and switched outside the engine casing.