JP2002155706A - Axial flow gas turbine equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformize temperature distribution in the circumferential direction of a turbine casing in horizontal axial flow gas turbine equipment having an enclosure. SOLUTION: This axial flow gas turbine equipment comprises a gas turbine rotor 24 of which a shaft 31 is arranged horizontally, a rotor blade 18 fitted on the gas turbine rotor 24, turbine casing 16 for forming part of a passage of gas turbine working medium by enveloping the outer periphery of the rotor blade 18. The axial flow gas turbine equipment includes an enclosure 5 forming a space 30 outside the turbine casing 16 and covering the outside of the space 30, means 7, 8, 9, 10 which flow coolant through the space 30 between the turbine casing 16 and the enclosure 5 in the direction of the shaft 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial gas turbine system installed with its shaft oriented sideways, and more particularly to a method for ventilating and cooling a turbine casing and an exhaust duct.

[0002]

2. Description of the Related Art In a conventional gas turbine facility, a soundproof enclosure for reducing gas turbine noise may be installed. Ventilation and cooling in this case are designed to prevent noise leakage to the operating floor as much as possible, and to efficiently ventilate the heat generated by the gas turbine equipment inside the soundproof enclosure. General ventilation methods utilizing natural convection phenomenon (See, for example,
No. 159094).

[0003] In this case, for example, a ventilation method is employed in which a cooling medium (atmospheric air) is taken in at a position of a side wall portion of the soundproof enclosure below a mount on which a gas turbine is installed, and is taken out from a duct at the upper rear of the gas turbine equipment. The gas turbine body exchanges heat with the gas turbine casing surface and is cooled by the flow of the cooling medium (flow from the lower part to the upper part of the gas turbine) inside the soundproof enclosure by the ventilation method described above.

[0004]

In the conventional gas turbine equipment, as shown in FIG. 7, a gas turbine device 4 is installed on a base 2 with its shaft oriented sideways. It is covered with a casing 16.
The outside of the turbine casing 16 is covered with an enclosure 55 also having a soundproofing device.

The working fluid that has exited the gas turbine device 4 is discharged outside the enclosure 55 through an exhaust duct 6 arranged downstream of the gas turbine device 4 in the axial direction.

An inlet 57 for the cooling medium, that is, the atmosphere, of the enclosure 55 is provided below the gas turbine device 4, and an outlet 58 for the cooling medium is provided for the gas turbine device 4.
It is provided above. The cooling medium exiting from the cooling medium outlet 58 passes through a cooling medium duct 59 and is supplied to the fan 60.
Is to be released to the atmosphere.

In this case, as indicated by an arrow 21 in the figure,
The cooling medium flows from the lower part of the turbine casing 16 to the upper part (in a direction perpendicular to the axis), and the turbine casing 1
6 is cooled. For this reason, the turbine casing 1
The surface temperature of No. 6 varies depending on the circumferential portion of the casing.

That is, since the temperature of the cooling medium is low (atmospheric temperature) on the lower surface of the turbine casing 16 near the cooling medium intake 57, the temperature is relatively low, and the upper surface of the turbine casing 16 near the cooling medium discharge 58. On the surface, the temperature of the cooling medium itself increases due to heat absorption, so that the surface temperature of the turbine casing 16 also becomes relatively high. As a result, as shown in FIG. 8, a temperature difference occurs between the lower portion (casing lower half 23) and the upper portion (casing upper half 22) of the turbine casing 16, and a circumferential temperature distribution occurs in the turbine casing 16. This results in uneven thermal expansion in the circumferential direction of the turbine casing 16 and uneven thermal deformation in the lower and upper portions of the turbine casing 16.

On the other hand, as shown in FIG. 9, a gas turbine rotor 24 having a rotating shaft 31 horizontal is rotatably supported inside the turbine casing 16. Are mounted so as to be aligned in the axial direction.

A plurality of shroud segments 17 are supported and fixed inside the turbine casing 16. Each shroud segment 17 protrudes in the circumferential direction along the inner surface of the turbine casing 16 so as to face the tip of each bucket 18. Each shroud segment 17 serves to maintain a clearance 20 between the tip of the rotor blade 18 as a rotating part and the shroud segment 17 as a stationary part. By keeping the clearance 20 as small as possible within a range where the stationary part and the fixed part do not come into contact with each other, the loss at the blade 18 can be reduced and the turbine efficiency can be increased. A plurality of stages of stationary blades 19 are attached to the shroud segment 17, and each stationary blade 19 is
8 and are alternately arranged adjacent to each other in the axial direction.

When uneven heat deformation occurs in the upper half and the lower half of the turbine casing 16, the clearance 20 between the shroud segment 17 and the moving blade 18 also changes in the circumferential direction. As the clearance 20 increases, the amount of combustion gas passing through the clearance increases. This results in increased losses at the rotor blades and lowers turbine efficiency. Conversely, if the clearance 20 is reduced, smooth rotation of the gas turbine may be hindered.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has as its object to equalize the circumferential temperature distribution of a turbine casing of an axial gas turbine facility having an enclosure which is installed with a shaft oriented sideways. I do.

[0013]

SUMMARY OF THE INVENTION The present invention attains the above object. According to the first aspect of the present invention, there is provided a gas turbine rotor installed with its shaft oriented sideways, and a gas turbine rotor mounted on the gas turbine rotor. In an axial-flow gas turbine facility having a moving blade and a turbine casing that envelopes the outer periphery of the moving blade and forms a part of a flow path of a gas turbine working gas, a space is formed outside the turbine casing. Having an enclosure surrounding the outside of the space, and means for flowing a cooling medium in the axial direction into the space between the turbine casing and the enclosure,
An axial gas turbine facility characterized by the following.

Accordingly, heat exchange with the cooling medium is performed in the axial direction on the casing surface of the gas turbine device, so that the temperature distribution on the casing surface is relatively uniform in the circumferential direction at a certain axial position. As a result, the thermal deformation of the casing becomes uniform in the circumferential direction, so that the clearance between the shroud segment, which is a component inside the casing, and the rotor blade can be kept uniform in the circumferential direction, and the clearance is minimized. It becomes possible.

Further, according to the invention of claim 2, an intake port for supplying air for operating the axial gas turbine equipment into the turbine casing is disposed near an end of the shaft, and the cooling medium is supplied to the shaft. A cooling medium intake for introduction into the enclosure is provided near one end near or far from the intake intake;
The axial gas turbine equipment according to claim 1, wherein:

According to a third aspect of the present invention, a turbine casing portion guide plate for guiding the cooling medium near the outer surface of the turbine casing in the enclosure is disposed. Or 2 axial gas turbine equipment.

According to the third aspect of the present invention, the axial flow velocity of the cooling medium near the outer surface of the turbine casing is increased, and the uniformity of the circumferential temperature distribution of the turbine casing is promoted.

Further, according to the present invention, an exhaust duct for discharging exhaust gas is coaxially connected in the enclosure downstream of the turbine casing, and the cooling medium is exhausted in the enclosure. The axial flow gas turbine equipment according to any one of claims 1 to 3, wherein an exhaust part guide plate for guiding the exhaust part near the outer surface of the duct is arranged.

According to the fourth aspect of the present invention, the exhaust duct guide plate increases the axial flow velocity of the cooling medium on the outer surface of the exhaust duct, thereby facilitating the cooling of the exhaust duct. Thus, the temperature distribution in the circumferential direction on the surface of the exhaust duct can be made uniform, whereby the influence of thermal deformation on the turbine casing of the gas turbine device to be fitted with the exhaust duct can be reduced.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. However, parts common to the related art are denoted by common reference numerals, and description thereof will be omitted as appropriate. (First Embodiment) (corresponding to claims 1 and 2) FIG. 1 is a configuration diagram of a first embodiment of the present invention. The gas turbine device 4 is installed on the base 2 with the shaft oriented sideways, and the gas turbine device 4 is covered with a turbine casing 16. The outside of the turbine casing 16 is covered with an enclosure 5 also having a soundproof device, and an annular space 30 through which a cooling medium passes in the axial direction is formed between the turbine casing 16 and the enclosure 5.

The working fluid that has exited the gas turbine device 4 is discharged to the outside of the enclosure 5 through an exhaust duct 6 arranged on the downstream side in the axial direction of the gas turbine device 4.

An inlet 7 for the cooling medium, that is, the atmosphere, of the enclosure 5 is provided on the intake side (the intake plenum 3 side) of the gas turbine device 4, and an outlet 8 for the cooling medium is provided for the exhaust gas duct of the gas turbine device 4. It is provided on the 6 side. The cooling medium coming out of the cooling medium outlet 8 is
The air is discharged to the atmosphere by a fan 10 through a cooling medium duct 9.

As shown by an arrow 11 in FIG.
In 0, a flow of the cooling medium is formed along the outer surface of the turbine casing 16 in the axial direction. As a result, the temperature distribution on the surface of the turbine casing 16 of the gas turbine device 4 becomes uniform in the circumferential direction at each axial position, and the thermal deformation of the turbine casing 16 becomes uniform in the circumferential direction.
For this reason, it is possible to keep the clearance 20 between the shroud segment 17 and the rotor blade 18 which are components inside the turbine casing 16 uniform in the circumferential direction, and to minimize the clearance 20 (see FIG. 9). ).

(Second Embodiment) (corresponding to Claims 1 and 2) FIG. 2 is a configuration diagram of a second embodiment of the present invention. Second
The main differences between this embodiment and the first embodiment are as follows. That is, in the second embodiment, the cooling medium intake 37 of the enclosure 35 is provided on the exhaust gas duct 6 side of the gas turbine device 4, and the cooling medium outlet 38 is connected to the intake intake side of the gas turbine device 4 ( It is provided on the intake plenum 3 side).

The cooling medium discharged from the cooling medium outlet 38 is discharged to the atmosphere by a fan 40 through a cooling medium duct 39. Therefore, an annular space 50 through which the cooling medium passes in the axial direction is formed between the turbine casing 16 and the enclosure 35, and the cooling medium passes through the annular space 50 on the surface of the gas turbine device 4 along the axial direction. A stream 41 is formed. However, the flow 41 is a flow opposite to the flow 11 (FIG. 1) of the first embodiment. Other configurations are almost the same as those of the first embodiment.

According to this embodiment, similarly to the first embodiment, the temperature distribution on the surface of the turbine casing 16 of the gas turbine device 4 is uniform in the circumferential direction at a certain axial position.

(Third Embodiment) (Claims 1, 2, and 3)
FIG. 3 is a configuration diagram of the third embodiment of the present invention. This embodiment is similar to the first embodiment (see FIG. 1), except that the turbine casing part guide plate 12 is provided to guide the cooling medium flowing through the annular space 30 near the outer surface of the turbine casing 16. The difference is in the arrangement. The turbine casing part guide plate 12 is attached to the periphery of the turbine casing 16 inside the enclosure 5 and inside the base 2. Other configurations are the same as those of the first embodiment. The turbine casing portion guide plate 12 increases the axial flow velocity of the cooling medium on the outer surface of the turbine casing 16, thereby facilitating the cooling of the turbine casing 16. Thereby, the circumferential temperature distribution on the surface of the turbine casing 16 of the gas turbine device 4 can be made more uniform.

(Fourth Embodiment) (Claims 1, 2, and 3)
FIG. 4 is a configuration diagram of a fourth embodiment of the present invention. This embodiment is different from the second embodiment (see FIG. 2) in that the third embodiment
A turbine casing part guide plate 42 corresponding to the turbine casing part guide plate 12 of the embodiment (see FIG. 3) is provided.

According to this embodiment, the turbine casing portion guide plate 42 increases the axial flow velocity of the cooling medium on the surface of the turbine casing 16, thereby facilitating the cooling of the turbine casing 16. Thereby, the circumferential temperature distribution on the surface of the turbine casing 16 of the gas turbine device 4 can be made more uniform as compared with the second embodiment.

(Fifth Embodiment) (Claims 1, 2,
FIG. 5 is a configuration diagram of a fifth embodiment of the present invention. This embodiment is similar to the third embodiment (see FIG. 3), except that the cooling medium flowing through the annular space 30 is supplied to the exhaust duct 6.
(Exhaust diffuser duct 14 and Exhaust expansion joint 15) is different in that an exhaust duct portion guide plate 13 is disposed near the outer surface. The exhaust duct guide plate 13 is attached to the periphery of the exhaust duct 6 inside the enclosure 5 and inside the base 2. Other configurations are the same as those of the third embodiment.
The exhaust duct portion guide plate 13 increases the axial flow velocity of the cooling medium on the outer surface of the exhaust duct 6, thereby facilitating the cooling of the exhaust duct 6.

As a result, the temperature distribution in the circumferential direction on the surface of the exhaust duct 6 can be made uniform, whereby the influence of thermal deformation on the turbine casing 16 of the gas turbine device 4 to be fitted with the exhaust duct 6 can be reduced.

(Sixth Embodiment) (Claims 1, 2,
FIG. 6 is a configuration diagram of a sixth embodiment of the present invention. The present invention is similar to the fourth embodiment (see FIG. 4), but arranges an exhaust duct part guide plate 43 to guide the cooling medium flowing through the annular space 50 near the outer surface of the exhaust duct 6. Is different. This exhaust duct portion guide plate 43 is
Exhaust duct part guide plate 1 of the fifth embodiment (see FIG. 5)
3 and is attached to the periphery of the exhaust duct 6 inside the enclosure 5 and inside the base 2. Other configurations are the same as those of the fifth embodiment. The exhaust duct 6 is guided by the exhaust duct guide plate 43.
The axial flow velocity of the cooling medium on the outer surface of the air duct increases, and the cooling of the exhaust duct 6 can be promoted.

Thus, the temperature distribution in the circumferential direction on the surface of the exhaust duct 6 can be made uniform, thereby reducing the influence of thermal deformation on the turbine casing 16 of the gas turbine device 4 to be fitted with the exhaust duct 6.

[0034]

As is clear from the above, according to the present invention, the temperature distribution on the casing surface of the gas turbine device is
Since a certain axial position becomes uniform in the circumferential direction and the thermal deformation of the casing becomes uniform in the circumferential direction, the clearance between the shroud segment, which is a component inside the casing, and the moving blade can be kept uniform in the circumferential direction. It becomes possible and the clearance can be minimized. This makes it possible to reduce the loss in the rotor blade portion and to further improve the turbine efficiency as compared with the related art.

[Brief description of the drawings]

FIGS. 1A and 1B are configuration diagrams of a gas turbine facility according to a first embodiment of the present invention, wherein FIG.
(B) is a front cross-sectional view, and (c) is a view taken in the direction of arrows CC in (b).

FIGS. 2A and 2B are configuration diagrams of a gas turbine equipment according to a second embodiment of the present invention, wherein FIG.
(B) is a front cross-sectional view, and (c) is a view taken in the direction of arrows CC in (b).

FIGS. 3A and 3B are configuration diagrams of a gas turbine facility according to a third embodiment of the present invention, wherein FIG.
(B) is a front cross-sectional view, and (c) is a view taken in the direction of arrows CC in (b).

FIGS. 4A and 4B are configuration diagrams of a gas turbine equipment according to a fourth embodiment of the present invention, wherein FIG.
(B) is a front cross-sectional view, and (c) is a view taken in the direction of arrows CC in (b).

FIGS. 5A and 5B are configuration diagrams of a gas turbine facility according to a fifth embodiment of the present invention, wherein FIG.
(B) is a front cross-sectional view, and (c) is a view taken in the direction of arrows CC in (b).

FIGS. 6A and 6B are configuration diagrams of a gas turbine facility according to a sixth embodiment of the present invention, wherein FIG.
(B) is a front cross-sectional view, and (c) is a view taken in the direction of arrows CC in (b).

FIG. 7 is a configuration diagram of a conventional gas turbine facility,
(A) is an AA arrow view of (b), (b) is a front sectional view.

FIG. 8 is a graph showing a temperature distribution of a conventional turbine casing.

FIG. 9 is a sectional view of a main part inside the turbine casing of FIG. 7 (b).

[Explanation of symbols]

1 ... intake duct, 2 ... foundation, 3 ... intake plenum, 4 ...
Gas turbine device, 5 ... enclosure, 6 ... exhaust duct, 7 ... cooling medium intake, 8 ... cooling medium outlet, 9 ...
Cooling medium duct, 10: fan, 11: flow of cooling medium in the axial direction, 12: guide plate of turbine casing section, 13: guide plate of exhaust duct section, 14: exhaust diffuser duct, 1
5: Exhaust expansion joint, 16: Turbine casing, 17: Shroud segment, 18: Blade, 19: Stator blade, 20: Clearance, 21: Flow of coolant in the direction perpendicular to the axis, 22: Upper half of casing, 23: Lower casing Half, 24 ... gas turbine rotor, 30 ... annular space, 31 ... rotating shaft, 35 ... enclosure, 37 ... intake, 38 ... exhaust, 39 ... duct, 40 ... fan, 4
Reference numeral 2: turbine casing portion guide plate, 43: exhaust duct portion guide plate, 50: annular space, 55: enclosure, 57
.., Cooling medium intake, 58, cooling medium outlet, 59, duct, 60, fan.

Claims (4)

[Claims] 1. A gas turbine rotor installed with its axis oriented sideways, a moving blade attached to the gas turbine rotor, and a gas turbine working gas flow path envelopably covering the outer periphery of the moving blade. A turbine casing forming a part, wherein an enclosure forming a space outside the turbine casing and surrounding the outside of the space, and cooling the space between the turbine casing and the enclosure. Means for flowing a medium in the axial direction, comprising: an axial flow gas turbine facility. 2. An air intake for supplying air for operating the axial gas turbine facility into the turbine casing is disposed near an end of the shaft, and is provided for introducing the cooling medium into the enclosure. The cooling medium intake is
The axial flow gas turbine equipment according to claim 1, wherein the gas turbine equipment is provided near one end on a side close to or far from the intake intake. 3. An axial gas turbine according to claim 1, further comprising a turbine casing portion guide plate for guiding the cooling medium near an outer surface of the turbine casing in the enclosure. Facility. 4. On the downstream side of the turbine casing,
An exhaust duct for discharging exhaust gas is coaxially connected in the enclosure, and an exhaust guide plate for guiding the cooling medium near an outer surface of the exhaust duct is disposed in the enclosure. The axial gas turbine equipment according to any one of claims 1 to 3, wherein: