Communicating structure between adjacent combustors and turbine portion and gas turbine

In a communicating structure between combustors that generates combustion gas inside pipe pieces and a turbine portion that generates a rotational driving force by making the combustion gas sequentially pass through a turbine stage formed of turbine stator vanes and turbine rotor blades, at least some of the first-stage turbine stator vanes closest to the combustor among the turbine stator vanes are disposed downstream of sidewalls of one pipe piece and another pipe piece that are adjacent to each other, and the distance from leading edges of the first-stage turbine stator vanes disposed downstream of the sidewalls of the pipe pieces to end portions of the sidewalls closer to the turbine portion is equal to or less than a spacing between an internal surface of the sidewall of the one pipe piece and an internal surface of the sidewall of the other pipe piece.

TECHNICAL FIELD

The present invention relates to a communicating structure between a combustor and a turbine portion and to a gas turbine.

BACKGROUND ART

A gas turbine generally includes a compressor, a combustor, and a turbine portion as main components; the compressor is coupled to a turbine with a rotating shaft; and the combustor is disposed between the compressor and the turbine portion.

In the above-described gas turbine, air, which is working fluid, is taken into the compressor, which is rotationally driven by the rotating shaft, to be compressed therein, and the compressed air is introduced into the combustor. Fuel is mixed with the compressed gas in the combustor, and high-temperature, high-pressure combustion gas is generated by combustion of the mixed air. The combustion gas is expelled to the turbine portion from the combustor to rotationally drive the turbine portion.

Specifically, the high-temperature working fluid expelled from the combustor, which includes the combustion gas, passes through between first-stage turbine stator vanes in the turbine portion and subsequently flows to first-stage turbine rotor blades. At the first-stage turbine rotor blades, part of the energy possessed by the working fluid is converted to rotational energy and is transmitted to the rotating shaft as a rotational driving force.

Normally, a rear end of a tail pipe of the combustor and leading edges of the first-stage turbine stator vanes positioned most upstream of the turbine portion are disposed with gaps therebetween. Accordingly, there is a problem in that part of the high-temperature working fluid that flows toward the turbine portion from the combustor flows into the gaps between the rear end of the tail pipe and the leading edges of the first-stage turbine stator vanes, and a loss occurs caused by this flow.

In addition, there is a problem in that the leading edges of the first-stage turbine stator vanes are heated by the high-temperature working fluid that has flowed into the gaps, and thus, a large amount of cooling fluid is required.

As a technique for solving the above-described problems, a method in which the first-stage turbine stator vanes are brought close to the combustor has been proposed (for example, see Patent Literature 1).

With the technique disclosed in Patent Literature 1, the leading edges of the first-stage turbine stator vanes are surrounded by the rear end of the combustor, and cooling fluid for cooling the first-stage turbine stator vanes is supplied from the tail pipe via slits formed at the leading edges. By doing so, the high-temperature working fluid does not collide with the leading edges of the first-stage turbine stator vanes, and the cooling fluid that was previously employed to cool the leading edges is not required.

CITATION LIST

Patent Literature

SUMMARY OF INVENTION

Technical Problem

However, with the above-described technique disclosed in Patent Literature 1, although integration of the combustor and the first-stage turbine stator vanes is described, there is no disclosure about the shape of an inner wall of the combustor inside which the high-temperature working fluid flows.

Because of this, the flow of the high-temperature working fluid that flows along the inner wall of the combustor is sometimes disturbed at a connecting portion between the inner wall and the first-stage turbine stator vanes. There is a problem in that this disturbance in the flow of the working fluid may affect the efficiency of the gas turbine.

On the other hand, when the flow of the working fluid is disturbed at the connecting portion between the inner wall and the first-stage turbine stator vanes as described above, the flow of working fluid in the peripheries of the first-stage turbine stator vanes is disturbed. Accordingly, there is a problem in that it is difficult to supply cooling fluid from between the combustor and the first-stage turbine stator vanes and to form a film-like layer of cooling fluid at the surfaces of the first-stage turbine stator vanes, which makes cooling of the first-stage turbine stator vanes difficult.

The present invention has been conceived in order to solve the above-described problems, and an object thereof is to provide a communicating structure between a combustor and a turbine portion and a gas turbine that are capable of suppressing the occurrence of a loss and also capable of reducing the flow level of cooling fluid employed in cooling turbine blades.

Solution To Problem

In order to achieve the above-described object, the present invention provides the following solutions.

A communicating structure between combustors and a turbine portion according to a first aspect of the present invention is a communicating structure between combustors that generate combustion gas by combusting compressed air supplied from a compressor and fuel supplied from fuel nozzles, which are mixed inside a plurality of pipe pieces disposed next to each other around a rotating shaft, and a turbine portion that generates a rotational driving force by making the combustion gas sequentially pass through a turbine stage formed of a plurality of turbine stator vanes and turbine rotor blades disposed around the rotating shaft, wherein at least some of first-stage turbine stator vanes closest to the combustors among the turbine stator vanes are disposed downstream of sidewalls of one pipe piece and another pipe piece that are adjacent to each other, and the distance from leading edges of the first-stage turbine stator vanes disposed downstream of the sidewalls to end portions of the sidewalls closer to the turbine portion is equal to or less than a spacing between an internal surface of the sidewall of the one pipe piece and an internal surface of the sidewall of the other pipe piece.

With the communicating structure between the combustors and the turbine portion according to the first aspect of the present invention, by disposing the first-stage turbine stator vanes positioned downstream of the sidewalls close to the end portions of the sidewalls closer to the turbine portion, the combustion gas is prevented from flowing in between the sidewalls and the first-stage turbine stator vanes. Accordingly, the occurrence of a loss due to the inflow of the combustion gas between the sidewalls and the first-stage turbine stator vanes is suppressed.

Furthermore, by disposing the first-stage turbine stator vanes close to the downstream side of sidewalls, the leading edges of the first-stage turbine stator vanes are disposed in relatively cool flows behind (in the wake of) the sidewalls, and thus, the high-temperature combustion gas is less likely to directly collide with the leading edges of the first-stage turbine stator vanes. Accordingly, the need to cool the leading edges of the first-stage turbine stator vanes is reduced, and the flow level of the cooling fluid required for cooling is reduced.

In the communicating structure between the combustors and the turbine portion according to the first aspect of the present invention, it is desirable that the internal surfaces of the sidewalls have shapes that are smoothly continuous with external surfaces of the first-stage turbine stator vanes disposed downstream of the sidewalls.

With this configuration, the combustion gas generated inside the pipe pieces flows along the internal surfaces of the sidewalls and subsequently flows along the external surfaces of the first-stage turbine stator vanes that are smoothly continuous with the sidewalls. Accordingly, as compared with the case in which level differences, etc. are formed between the internal surfaces of the sidewalls and the external surfaces of the first-stage turbine stator vanes thereby making them discontinuous, the flow of combustion gas is less likely to be disturbed and the occurrence of the loss can be suppressed.

Furthermore, because the flow of combustion gas at the external surfaces of the first-stage turbine stator vanes is less likely to be disturbed, for example, in the method in which the first-stage turbine stator vanes are cooled by making the cooling fluid flow in the form of a film at the external surfaces of the first-stage turbine stator vanes, deterioration in the efficiency of cooling the first-stage turbine stator vanes can be suppressed.

On the other hand, an increase in heat transmission rate from the combustion gas to the external surfaces of the first-stage turbine stator vanes is suppressed.

Furthermore, because the leading edges of the first-stage turbine stator vanes, where the temperature thereof most easily reaches a high temperature, are protected by the sidewalls (disposed in the wake of the side walls), exposure to the high-temperature combustion gas is prevented, and the flow level of the cooling fluid required to cool the first-stage turbine stator vanes can be reduced.

In the communicating structure between the combustors and the turbine portion according to the first aspect of the present invention, it is desirable that, as compared with the first-stage turbine stator vanes disposed at locations other than downstream of the sidewalls, the number of cooling holes from which cooling fluid employed to cool the first-stage turbine stator vanes is made to flow out to the peripheries of the first-stage turbine stator vanes be smaller in the first-stage turbine stator vanes disposed downstream of the sidewalls.

With this configuration, the combustion gas is less likely to collide with the leading edges of the first-stage turbine stator vanes disposed downstream of the sidewalls, as compared with the first-stage turbine stator vanes disposed elsewhere. Accordingly, as compared with the first-stage turbine stator vanes disposed at locations other than downstream of the sidewalls, it is possible to reduce the number of cooling holes or shower-head cooling holes, from which the cooling fluid is made to flow out to the peripheries of the first-stage turbine stator vanes disposed downstream of the sidewalls so as to flow along the external surfaces of the first-stage turbine stator vanes in the form of a film. In other words, as compared with the first-stage turbine stator vanes disposed at locations other than downstream of the sidewalls, the flow level of the cooling fluid employed to cool the first-stage turbine stator vanes can be reduced.

In the communicating structure between the combustors and the turbine portion according to the first aspect of the present invention, it is desirable that the cooling fluid for cooling the sidewalls be made to flow through a gap between a sidewall of the one pipe piece and a sidewall of the other pipe piece and that the cooling fluid that has cooled the sidewalls subsequently flow along the peripheries of the first-stage turbine stator vanes disposed downstream of the sidewalls from downstream-side end portions of the sidewalls.

With this configuration, by making the cooling fluid that has flowed between the sidewalls and cooled the sidewalls flow along the peripheries of the first-stage turbine stator vanes in the form of a film from the outflow channels, which are slot-like gaps formed between the downstream-side end portions of the sidewalls and the first-stage turbine stator vanes, the first-stage turbine stator vanes disposed downstream of the sidewalls can be effectively cooled by the cooling fluid. Accordingly, the flow level of the cooling fluid that is supplied to the first-stage turbine stator vanes disposed downstream of the sidewalls and that cools the first-stage turbine stator vanes can be reduced.

In the communicating structure between the combustors and the turbine portion according to the first aspect of the present invention, it is desirable that the downstream-side end portions of the sidewalls be tilted in the direction in which the combustion gas is deflected by the first-stage turbine stator vanes.

With this configuration, the flow of combustion gas can be deflected by the downstream-side end portions of the sidewalls and the first-stage turbine stator vanes.

Furthermore, because the flow of combustion gas is deflected by the sidewalls and the first-stage turbine stator vanes, the size of the communicating structure between the combustors and the turbine portion in the axial direction of the rotating shaft can be reduced. On the other hand, when the deflection by the sidewalls can be increased, the deflection by the first-stage turbine stator vanes can be reduced; therefore, the axial-direction size can be further reduced.

In the communicating structure between the combustors and the turbine portion according to the first aspect of the present invention, it is desirable that the tilted portions of the sidewalls, in cross-sectional view, form airfoil shapes together with the first-stage turbine stator vanes disposed downstream of the sidewalls.

With this configuration, because the tilted portions of the sidewalls have cross-sectional shapes that form airfoil shapes together with the first-state turbine stator vanes, the flow of the combustion can be effectively deflected as compared with the case in which the airfoil shapes are not formed.

A gas turbine according to a second aspect of the present invention is a gas turbine including a compressor that compresses air; a combustor that generates combustion gas by combusting compressed air supplied from the compressor and fuel supplied from a fuel nozzle, which are mixed therein; a turbine portion that converts part of energy possessed by the combustion gas into a rotational driving force; a rotating shaft that transmits the rotational driving force from the turbine portion to the compressor; and the communicating structure between the combustors and the turbine portion of the present invention described above.

With the gas turbine according to the second aspect of the present invention, because it has the communicating portion between the combustors and the turbine portion according to the present invention described above, the occurrence of a loss can be suppressed and the flow level of the cooling volume employed to cool the turbine stator vanes can be reduced; therefore, the efficiency of the gas turbine as a whole can be improved.

Advantageous Effects of Invention

With the communicating structure between combustors and a turbine portion and the gas turbine according to the present invention, an advantage is afforded in that, by disposing first-stage turbine stator vanes positioned downstream of sidewalls closer to end portions of the sidewalls close to a turbine-portion, the occurrence of a loss in a gas turbine can be suppressed, and the flow level of cooling fluid employed to cool turbine blades can also be reduced.

DESCRIPTION OF EMBODIMENTS

First Embodiment

FIG. 1is a schematic view for explaining the configuration of a gas turbine according to this embodiment.

As shown inFIG. 1, in this embodiment, a gas turbine1of the present invention will be described as applied to one that drives a generator G. However, the object to be driven by the gas turbine1is not limited to the generator G, and it may be other equipment; it is not particularly limited.

As shown inFIG. 1, the gas turbine1is mainly provided with a compressor2, combustors3, a turbine portion4, and a rotating shaft5.

The compressor2takes in atmospheric air, which is external air, compresses the air, and supplies the compressed air to the combustors3.

The compressor2is provided with an inlet guiding vane (not shown) which adjusts the flow level of the atmospheric air that flows into the compressor2, first-stage rotor blades (not shown) that compress the atmospheric air that has flowed in, first-stage stator vanes (not shown), and so on.

FIG. 2is a schematic view for explaining the configurations of the compressor, the turbine portion, and the combustor inFIG. 1.

As shown inFIGS. 1 and 2, the combustors3are can-type combustors in which the air compressed by the compressor2and externally supplied fuel are mixed and that generates high-temperature combustion gas by combusting the mixed air that has been mixed therein.

As shownFIG. 2, the combustors3are mainly provided with air inlets31, fuel nozzles32, and tail pipes (tube pieces)33.

As shown inFIG. 2, the air inlets31guide the air compressed by the compressor2to the interior of the tail pipes33and are each disposed in the form of a ring around the fuel nozzles32. Furthermore, the air inlets31impart the air flowing into the interior of the tail pipes33with flow speed components in a swirling direction, thus forming circulating flows inside the tail pipes33.

Note that a known shape can be employed for the air inlets31; they are not particularly limited.

As shown inFIG. 2, the fuel nozzles32spray the externally supplied fuel into the interior of the tail pipes33. The fuel sprayed from the fuel nozzles32is stirred by the airflow formed by the air inlets31, etc. to form mixed air containing fuel and air.

Note that a known shape can be employed for the fuel nozzles32; it is not particularly limited.

As shown inFIG. 2, the tail pipes33are pipe-shaped members that extend toward an inflow portions of the turbine portion4from the air inlets31and the fuel nozzles32. In other words, the tail pipes33are where the mixed air containing fuel and air and the combustion gas generated by the combustion of the mixed air flow in the interior thereof.

The sectional shape of the tail pipes33near the fuel nozzles32is substantially circular, and the sectional shape thereof near the turbine portion4is substantially rectangular. Accordingly, the sectional shape of the tail pipes33continuously changes from a substantially circular shape to a substantially rectangular shape from the fuel nozzles32toward the turbine portion4.

As shown inFIGS. 1 and 2, the turbine portion4receives a supply of high-temperature gas generated by the combustors3to generate a rotational driving force and transmits the generated rotational driving force to the rotating shaft5.

FIG. 3is a partially enlarged view for explaining the communicating structure between the combustor and the turbine portion inFIG. 1.

The first-stage turbine stator vanes4SV form a turbine stage together with the first-stage turbine rotor blades4RB and generate the rotational driving force together with the first-stage rotor blades4RB from the high-temperature gas that has flowed into the turbine portion4.

The first-stage turbine stator vanes4SV are a plurality of blades that are arranged around the rotating shaft at equal intervals at positions that face downstream-side end portions (bottom-side end portions inFIG. 3) of the tail pipes33with respect to a flow of combustion gas and that are also arranged so as to extend along a radial direction (vertical direction inFIG. 3with respect to the plane of the drawing). Furthermore, the first-stage turbine stator vanes4SV deflect the combustion gas that has flowed into a row of the first-stage turbine stator vanes4SV from the combustors3in a circumferential direction (left-right direction inFIG. 3).

In this embodiment, the number of first-stage turbine stator vanes4SV is an integral multiple of the number of combustors3, and, at least some of the first-stage turbine stator vanes4SV are disposed downstream of sidewalls34of the tail pipes33in the combustors3, as shown inFIG. 3. Furthermore, the first-stage turbine stator vanes4SV are arranged so that a distance L from leading edges LE of the first-stage turbine stator vanes4SV to end portions of the sidewalls34closer to the turbine portion4is set to be equal to or less than a thickness T which is the sum of the thicknesses of the sidewall34of one tail pipe33and the sidewall34of another tail pipe33that are adjacent to each other, and gaps between the two sidewalls34and34are combined, in other words, the thickness T (hereinafter, referred to as “thickness T related to the sidewalls34”) is the spacing between the inner surface of the sidewall34of one tail pipe33and the inner surface of the sidewall34of another tail pipe, which are adjacent to each other.

Furthermore, the first-stage turbine stator vanes4SV are provided with cavities41to which cooling air (cooling fluid) that protects the first-stage turbine stator vanes4SV from the heat of the high-temperature gas flowing in the peripheries thereof is supplied and are provided with a plurality of cooling holes42that perform film cooling wherein the cooling air is made to flow out into the peripheries of the first-stage turbine stator vanes4SV from the cavities41.

The cooling holes42are arranged in a large number at the leading edges LE of the first-stage turbine stator vanes4SV, where the heat load is high, so that the leading edges LE are formed like shower heads.

When the numbers of cooling holes42at the leading edges LE are compared between the first-stage turbine stator vanes4SV disposed downstream of the sidewalls34and the rest of the first-stage turbine stator vanes4SV, a smaller number of cooling holes42is formed at the leading edges LE of the first-stage turbine stator vanes4SV disposed downstream of the sidewalls34.

The first-stage turbine rotor blades4RB form the turbine stage together with the first-stage turbine stator vanes4SV and generate the rotational driving force on the basis of the combustion gas deflected by the first-stage turbine stator vanes4SV.

The first-stage turbine rotor blades4RB are a plurality of blades that are arranged around the rotating shaft at equal intervals at positions downstream (right-side positions inFIG. 2) of the first-stage turbine stator vanes4SV with respect to the flow of combustion gas and that are also arranged so as to extend along the radial direction (top-bottom direction inFIG. 2). Furthermore, the first-stage turbine rotor blades4RB receive the combustion gas deflected by the first-stage turbine stator vanes4SV and rotationally drive the rotating shaft5.

Furthermore, cooling air that protects the first-stage turbine rotor blades4RB from the heat of the combustion gas that flows in the peripheries thereof is supplied to the first-stage turbine rotor blades4RB.

Note that the turbine portion4may be provided only with the first-stage turbine stator vanes4SV and the first-stage turbine rotor blades4RB, as described above, or second-stage turbine stator vanes and second-stage turbine rotor blades, third-stage turbine stator vanes and third-stage turbine rotor blades, and so on may be additionally provided; it is not particularly limited.

Next, the general operation of the thus-configured gas turbine1and the flow of the combustion gas from exits of the combustors3to the first-stage turbine stator vanes4SV, which is a feature of this embodiment, will be described.

As shown inFIG. 1, the gas turbine1takes in the atmospheric air (air) when the compressor2is rotationally driven. The air that has been taken in is compressed by the compressor2and is discharged toward the combustor3.

The compressed air that has flowed into the combustors3is mixed with the externally supplied fuel at the combustors3. The mixed air containing fuel and air is combusted in the combustors3, and the combustion gas is generated.

The combustion gas generated in the combustors3is supplied to the turbine portion4downstream of the combustors3.

As shown inFIG. 3, the combustion gas flows out from the tail pipes33of the combustors3and flows into the row of the first-stage turbine stator vanes4SV in the turbine4.

At this time, because the first-stage turbine stator vanes4SV are disposed close to the tail pipes33, the combustion gas is less likely to flow in between the first-stage turbine stator vanes4SV disposed downstream of the sidewalls34of the tail pipes33and the tail pipes33, and a loss due to this flow is less likely to occur.

Furthermore, the leading edges LE of the first-stage turbine stator vanes4SV disposed downstream of the sidewalls34are positioned in flows behind (in the wake of) the sidewalls34; therefore, the combustion gas is less likely to directly collide with the leading edges LE.

The flow direction of the combustion gas that has flowed into the row of the first-stage turbine stator vanes4SV is deflected in the circumferential direction (left-right direction inFIG. 3), centered around the rotating shaft5, and flows into the row of the first-stage turbine rotor blades4RB, as shown inFIG. 2.

The first-stage turbine rotor blades4RB are rotationally driven by the deflected combustion gas. The rotational driving force generated in this way at the turbine portion4is transmitted to the rotating shaft5. The rotating shaft5transmits the rotational driving force extracted at the turbine portion4to the compressor2and the generator G.

With the above-described configuration, the first-stage turbine stator vanes4SV positioned downstream of the sidewalls34are disposed close to the end portions of the sidewalls34closer to the turbine portion4, and thereby, the combustion gas is prevented from flowing in between the sidewalls34and the first-stage turbine stator vanes4SV. Because of this, the occurrence of loss caused by having the combustion gas flow in between the sidewalls34and the first-stage turbine stator vanes4SV can be suppressed.

Furthermore, by disposing the first-stage turbine stator vanes4SV close to the downstream side of the sidewalls34, the leading edges LE of the first-stage turbine stator vanes4SV are disposed in relatively cool flows behind (in the wake of) the sidewalls34, and the high-temperature combustion gas is less likely to directly collide with the leading edges LE of the first-stage turbine stator vanes4SV. Because of this, the need to cool the leading edges LE of the first-stage turbine stator vanes4SV is reduced, and the flow level of the cooling air required for cooling can be reduced.

The combustion gas is less likely to collide with the first-stage turbine stator vanes4SV disposed downstream of the sidewalls34at the leading edges LE thereof as compared with the first-stage turbine stator vanes4SV disposed elsewhere. Accordingly, as compared with the first-stage turbine stator vanes4SV disposed at locations other than downstream of the sidewalls34, it is possible to reduce the number of cooling holes42in the first-stage turbine stator vanes4SV, which cause the cooling air to flow along external surfaces thereof in the form of a film by making the cooling air flow out therefrom to the peripheries of the first-stage turbine stator vanes4SV. In other words, as compared with the first-stage turbine stator vanes4SV disposed at the locations other than the downstream of the sidewalls34, it is possible to reduce the flow level of the cooling air employed to cool the first-stage turbine stator vanes4SV disposed downstream of the sidewalls34.

Second Embodiment

Next, a second embodiment of the present invention will be described with reference toFIGS. 4 and 5.

Although the basic configuration of a gas turbine of this embodiment is the same as that of the first embodiment, a communicating structure between the combustors and the turbine portion differs from that in the first embodiment. Therefore, only the communicating structure between the combustors and the turbine portion will be described in this embodiment by usingFIGS. 4 and 5, and descriptions of other components, etc. will be omitted.

FIG. 4is a partially enlarged view for explaining the communicating structure between the combustors and the turbine portion in the gas turbine according to this embodiment.

Note that, components that are the same as those in the first embodiment are given the same reference signs, and descriptions thereof will be omitted.

As shown inFIG. 4, combustors103in a gas turbine101in this embodiment differ from those of the first embodiment in the shapes of the end portions (bottom-side end portions inFIG. 4) of sidewalls134of tail pipes (pipe pieces)133closer to a turbine portion104.

Specifically, as shown inFIG. 4, cooling channels145in which cooling fluid (for example, compressed air compressed by the compressor2), such as cooling air, etc., flows and that extend in a direction (top-bottom direction inFIG. 4) in which the combustion gas flows are provided between the tail pipes133of adjacent combustors103.

End portions of the cooling channels145closer to the turbine portion104are opened at the end portions (bottom-side end portions inFIG. 4) of the sidewalls134of the end pipes133closer to the turbine portion104.

FIG. 5is an enlarged view for explaining the configurations of the sidewalls and the first-stage turbine stator vanes inFIG. 4.

Furthermore, as shown inFIGS. 4 and 5, the downstream-side end portions of the sidewalls134are formed in shapes such that internal surfaces of the sidewalls134are smoothly continuous with external surfaces of first-stage turbine stator vanes104SV adjacent thereto. In other words, the sidewalls134are formed so that the widths of the sidewalls134are increased toward the first-stage turbine stator vanes104SV.

On the other hand, the first-stage turbine stator vanes4SV and first-stage turbine stator vanes (turbine stator vanes)104SV are provided at the turbine portion104in the gas turbine101of this embodiment, as shown inFIG. 4.

The first-stage turbine stator vanes4SV and the first-stage turbine stator vanes104SV form a turbine stage together with the first-stage turbine rotor blades4RB and generate a rotational driving force together with the first-stage rotor blades4RB from the combustion gas that has flowed into the turbine portion104. Furthermore, the first-stage turbine stator vanes4SV and the first-stage turbine stator vanes104SV are a plurality of blades that are arranged at equal intervals on the same circumference around the rotating shaft5and that are also arranged so as to extend along the radial direction (vertical direction inFIG. 4with respect to the plane of the drawing).

As shown inFIG. 4, the first-stage turbine stator vanes4SV are turbine stator vanes disposed between the sidewalls134, in other words, turbine stator vanes disposed between the first-stage turbine stator vanes104SV.

The first-stage turbine stator vanes104SV are turbine stator vanes disposed at positions facing the downstream-side end portions (bottom-side end portions inFIG. 4) of the end pipes133with respect to the flow of combustion gas, in other words, turbine stator vanes disposed between the first-stage turbine stator vanes4SV.

Unlike the first-stage turbine stator vanes4SV, the cavities41inside which the cooling air is supplied and the cooling holes42from which the cooling air from the cavities41is made to flow out to the peripheries of the first-stage turbine stator vanes104SV are not formed in the first-stage turbine stator vanes104SV.

On the other hand, as shown inFIGS. 4 and 5, outflow channels146that communicate with the cooling channels145at the sidewalls134and from which the cooling air, after flowing through the cooling channels145, flows out along the peripheries of the first-stage turbine stator vanes104SV in the form of a film are provided between the first-stage turbine stator vanes104SV and the sidewalls134.

The outflow channels146are long, narrow slots that extend from the cooling channels145toward the outer side of the sidewalls134in the downstream direction (right direction inFIG. 5) of the flow of combustion gas.

Next, the flow of combustion gas from the exits of the combustors103to the first-stage turbine stator vanes4SV and the first-stage turbine stator vanes104SV, which is a feature of this embodiment, will be described.

Note that, because the general operation of the gas turbine101is the same as that in the first embodiment, a description thereof will be omitted.

As shown inFIGS. 4 and 5, the combustion gas flows out from the tail pipes133of the combustors103and flows into a row of the first-stage turbine stator vanes4SV and the first-stage turbine stator vanes104SV at the turbine portion104.

Specifically, the combustion gas that has flowed along the internal surfaces of the sidewalls134of the tail pipes133is deflected while flowing along the external surfaces of first-stage turbine stator vanes104SV from the internal surface of the sidewalls134.

At the same time, the cooling air that has flowed through the cooling channels145and cooled the tail pipes133flows out along the external surfaces of the first-stage turbine stator vanes104SV via the outflow channels146. The cooling air flows along the external surfaces of the first-stage turbine stator vanes104SV in the form of a film and cools the first-stage turbine stator vanes104SV.

On the other hand, as in the case of the first embodiment, the combustion gas that has flowed through the centers of the tail pipes133collides with the first-stage turbine stator vanes4SV and is deflected while flowing along the surfaces of the first-stage turbine stator vanes4SV.

With the above-described configuration, the combustion gas generated inside the tail pipes133flows along the internal surfaces of the sidewalls134and subsequently flows along the external surfaces of the first-stage turbine stator vanes104SV, which are smoothly continuous therewith. Accordingly, as compared with the case in which the internal surfaces of the sidewalls134and the external surfaces of the first-stage turbine stator vanes104SV are discontinuous due to the formation of a level difference, etc. therebetween, the flow of combustion gas is less likely to be disturbed, and loss can be suppressed.

Furthermore, because the flow of combustion gas at the external surfaces of the first-stage turbine stator vanes104SV is less likely to be disturbed, with the approach in which the cooling air that has flowed out from the outflow channels146is made to flow at the external surfaces of the first-stage turbine stator vanes104SV in the form of a film to cool the first-stage turbine stator vanes104SV, deterioration of the cooling efficiency of the first-stage turbine stator vanes104SV can be prevented.

By making the cooling air that has cooled the sidewalls134flow along the external surfaces of the first-stage turbine stator vanes104SV, the first-stage turbine stator vanes104SV disposed downstream of the sidewalls134can be cooled with the cooling air. Accordingly, it is possible to reduce the flow level of the cooling air to be supplied to the first-stage turbine stator vanes104SV to cool the first-stage turbine stator vanes104SV.

Third Embodiment

Although the basic configuration of a gas turbine of this embodiment is the same as that of the first embodiment, a communicating structure between the combustors and the turbine portion differs from that in the first embodiment. Therefore, only the communicating structure between the combustors and the turbine portion will be described in this embodiment by usingFIG. 6, and descriptions of other components, etc. will be omitted.

FIG. 6is a partially enlarged view for explaining the communicating structure between the combustors and the turbine portion in the gas turbine according to this embodiment.

Note that components that are the same as those in the first embodiment are given the same reference signs, and descriptions thereof will be omitted.

As shown inFIG. 6, a combustor203in a gas turbine201of this embodiment differs from that in the first embodiment in the shapes of the end portions (bottom-side end portions inFIG. 6) of sidewalls234of tail pipes (pipe pieces)233closer to a turbine portion204.

Specifically, as shown inFIG. 6, the sidewalls234of the tail pipes233in the combustors203are provided with tilted portions235that are tilted in the direction in which the first-stage turbine stator vanes4SV deflect the flow of combustion gas.

The tilted portions235are end portions of the sidewalls234closer to the turbine portion204and are portions adjacent to the first-stage turbine stator vanes204SV. Furthermore, because the tilted portions235are formed by tilting the sidewalls234without other modifications, the thickness-wise size of the tilted portions235and the thickness-wise size of parts of the sidewalls234other than the tilted portions235are the same.

As shown inFIG. 6, the tail pipes233and the sidewalls234are provided with cooling channels145that extend along the direction in which the combustion gas flows (top-bottom direction inFIG. 6) and inside which cooling fluid, such as cooling air, etc., flows. Furthermore, the cooling channels145extend along the tilted portions235inside the tilted portions235of the sidewalls234.

The end portions of the cooling channels145closer to the turbine portion204open at the end portions (bottom-side end portions inFIG. 6) of the tilted portions235of the sidewalls234closer to the turbine portion204.

On the other hand, as shown inFIG. 6, the turbine portion204of the gas turbine201in this embodiment is provided with the first-stage turbine stator vanes4SV and the first-stage turbine stator vanes (turbine stator vanes)204SV.

The first-stage turbine stator vanes4SV and the first-stage turbine stator vanes204SV form a turbine stage together with the first-stage turbine rotor blades4RB and generate a rotational driving force together with the first-stage rotor blades4RB from the combustion gas that has flowed into the turbine portion204. Furthermore, the first-stage turbine stator vanes4SV and the first-stage turbine stator vanes204SV are a plurality of blades that are arranged at equal intervals on the same circumference around the rotating shaft5and that are also arranged so as to extend along the radial direction (vertical direction inFIG. 6with respect to the plane of the drawing).

As shown inFIG. 6, the first-stage turbine stator vanes4SV are turbine stator vanes disposed between the sidewalls234and the tilted portions235, in other words, turbine stator vanes disposed between the first-stage turbine stator vanes204SV.

The first-stage turbine stator vanes204SV are turbine stator vanes disposed at positions facing the downstream-side end portions (bottom-side end portions inFIG. 6) of the tilted portions235with respect to the flow of combustion gas, in other words, turbine stator vanes disposed between the first-stage turbine stator vanes4SV.

The first-stage turbine stator vanes204SV are formed with a smaller sectional area as compared with the first-stage turbine stator vanes4SV, and a portion in the first-stage turbine stator vanes204SV where the thickness-wise size is the largest has the same thickness-wise size as the tilted portions235.

Unlike the first-stage turbine stator vanes4SV, the cavities41inside which the cooling air is supplied and the cooling holes42from which the cooling air from the cavities41is made to flow out to the peripheries of the first-stage turbine stator vanes204SV are not formed in the first-stage turbine stator vanes204SV.

On the other hand, as shown inFIG. 6, outflow channels146that communicate with the cooling channels145at the tilted portions235and from which the cooling air, after flowing through the cooling channels145, flows out along the peripheries of the first-stage turbine stator vanes204SV are provided between the first-stage turbine stator vanes204SV and the tilted portions235.

The outflow channels146are through-holes that extend from the cooling channels145toward the outer side of the tilted portions235in the downstream direction (left-bottom direction inFIG. 6) of the flow of combustion gas.

Next, the flow of combustion gas from the exits of the combustors203to the first-stage turbine stator vanes4SV and the first-stage turbine stator vanes204SV, which is a feature of this embodiment, will be described.

Note that, because the general operation of the gas turbine201is the same as that in the first embodiment, a description thereof will be omitted.

As shown inFIG. 6, the combustion gas flows out from the tail pipes233of the combustors203and flows into the row of the first-stage turbine stator vanes4SV and the first-stage turbine stator vanes204SV at the turbine portion204.

Specifically, the combustion gas that has flowed along the internal surfaces of the sidewalls234of the tail pipes233is deflected while flowing along the internal surfaces of the tilted portions235at the sidewalls234and the external surfaces of first-stage turbine stator vanes204SV.

At the same time, the cooling air that has flowed through the cooling channels145and cooled the tail pipes233and the tilted portions235flows out along the external surfaces of the first-stage turbine stator vanes204SV via the outflow channels146. The cooling air flows along the external surfaces of the first-stage turbine stator vanes204SV in the form of a film and cools the first-stage turbine stator vanes204SV.

On the other hand, as in the case of the first embodiment, the combustion gas that has flowed through the interior of the tail pipes233collides with the first-stage turbine stator vanes4SV and is deflected while flowing along the surfaces of the first-stage turbine stator vanes4SV.

With the above-described configuration, the flow of combustion gas can be deflected by the tilted portions235, which are the downstream-side end portions of the sidewalls234, and the first-stage turbine stator vanes204SV.

Furthermore, because the flow of combustion gas is deflected by the tilted portions235and the first-stage turbine stator vanes204SV, it is possible to reduce the size of the communicating structure between the combustors203and the turbine portion204in the axial direction (top-down directionFIG. 6) of the rotating shaft5.

If the deflection by the sidewalls234can be further increased, the deflection by the first-stage turbine stator vanes204SV can be reduced; therefore, the size in the axial direction of the rotating shaft5can be further reduced.

Fourth Embodiment

Although the basic configuration of a gas turbine of this embodiment is the same as that of the first embodiment, a communicating structure between the combustors and the turbine portion differs from that in the first embodiment. Therefore, only the communicating structure between the combustors and the turbine portion will be described in this embodiment by usingFIG. 7, and descriptions of other components, etc. will be omitted.

FIG. 7is a partially enlarged view for explaining the communicating structure between the combustors and the turbine portion in the gas turbine according to this embodiment.

Note that components that are the same as those in the first embodiment are given the same reference signs, and descriptions thereof will be omitted.

As shown inFIG. 7, a turbine portion304in a gas turbine101of this embodiment differs from that in the first embodiment in the shapes and arrangement of first-stage turbine stator vanes (turbine stator vanes)304SV.

The first-stage turbine stator vanes304SV form a turbine stage together with the first-stage turbine rotor blades4RB and generate a rotational driving force together with the first-stage rotor blades4RB from the combustion gas that has flowed into the turbine portion304. Furthermore, the first-stage turbine stator vanes304SV are a plurality of blades that are arranged at equal intervals on the same circumference around the rotating shaft5and that are also arranged so as to extend along the radial direction (vertical direction inFIG. 7with respect to the plane of the drawing).

The first-stage turbine stator vanes304SV are disposed at positions facing the downstream-side end portions (bottom-side end portions inFIG. 7) of the sidewalls334of tail pipes333with respect to the flow of combustion gas. In other words, the first-stage turbine stator vanes304SV are provided in the same number as the number of combustors303.

The first-stage turbine stator vanes304SV have similar shapes to the first-stage turbine stator vanes4SV in the first embodiment, etc. and are formed with larger sectional areas.

Specifically, leading edges LE of the first-stage turbine stator vanes304SV are disposed at positions separated from the downstream-side end portions of the sidewalls334, at most, by the thickness T related to the sidewalls334, and trailing edges TE of the first-stage turbine stator vanes304SV are disposed at the same positions as trailing edges TE of conventional first-stage turbine stator vanes.

Next, the flow of combustion gas from exits of the combustors303to the first-stage turbine stator vanes304SV, which is a feature of this embodiment, will be described.

Note that, because the general operation of the gas turbine301is the same as that in the first embodiment, a description thereof will be omitted.

As shown inFIG. 7, the combustion gas flows out from the tail pipes333of the combustors103and flows into the row of the first-stage turbine stator vanes304SV at the turbine portion304.

Specifically, the combustion gas that has flowed along the internal surfaces of the sidewalls334of the tail pipes333is deflected while flowing along the external surfaces of the first-stage turbine stator vanes304SV.

At the same time, the cooling air that has flowed through the cooling channels145and cooled the tail pipe333flows out along the external surfaces of the first-stage turbine stator vanes304SV from the downstream-side end portions of the sidewalls334. The cooling air flows along the external surfaces of the first-stage turbine stator vanes304SV in the form of a film and cools the first-stage turbine stator vanes304SV.

With this configuration, as compared with the first embodiment, etc., the number of the first-stage turbine stator vanes304SV can be reduced. Accordingly, a reduction in flow speed of the combustion gas due to friction or the like that acts between the first-stage turbine stator vanes304SV and the combustion gas can be suppressed, and the loss caused by this can be suppressed.

Fifth Embodiment

Next, a fifth embodiment of the present invention will be described with reference toFIG. 8.

Although the basic configuration of a gas turbine of this embodiment is the same as that of the first embodiment, a communicating structure between the combustors and the turbine portion differs from that in the first embodiment. Therefore, only the communicating structure between the combustors and the turbine portion will be described in this embodiment by usingFIG. 8, and descriptions of other components, etc. will be omitted.

FIG. 8is a partially enlarged view for explaining the communicating structure between the combustors and the turbine portion in the gas turbine according to this embodiment.

Note that components that are the same as those in the first embodiment are given the same reference signs, and descriptions thereof will be omitted.

As shown inFIG. 8, combustors403in a gas turbine401of this embodiment differ from those in the first embodiment in the shapes of the end portions (bottom-side end portions inFIG. 8) of sidewalls434of tail pipes (pipe pieces)433closer to a turbine portion404.

Specifically, as shown inFIG. 8, the sidewalls434of the tail pipes433in the combustors403are provided with tilted portions435that deflect the flow of combustion gas leftward inFIG. 8.

The tilted portions435are end portions of the sidewalls434closer to the turbine portion404and are portions adjacent to the first-stage turbine stator vanes404SV. Furthermore, the tilted portions435are formed in shapes whose cross-sections form airfoil shapes together with the first-stage turbine stator vanes404SV.

Furthermore, upstream-side end portions (top-side end portions inFIG. 8) of the tilted portions435with respect to the flow of combustion gas are at positions equivalent to the leading edges LE of the first-stage turbine stator vanes304SV in the fourth embodiment.

As shown inFIG. 8, the cooling channels145in which cooling fluid (for example, compressed air compressed in the compressor2), such as cooling air, flows and that extend along the direction (top-down direction inFIG. 8) in which the combustion gas flows are provided between adjacent tail pipes433. Furthermore, the cooling channels145extend along the tilted portions435, between the tilted portions435of adjacent sidewalls434.

End portions of the cooling channels145open at downstream-side end portions (bottom-side end portions inFIG. 8) of the tilted portions435of the sidewalls434.

On the other hand, as shown inFIG. 8, the turbine portion404of the gas turbine401in this embodiment is provided with the first-stage turbine stator vanes (turbine stator vanes)404SV.

The first-stage turbine stator vanes404SV form a turbine stage together with the first-stage turbine rotor blades4RB and generate a rotational driving force together with the first-stage rotor blades4RB from the combustion gas that has flowed into the turbine portion404. Furthermore, the first-stage turbine stator vanes404SV are a plurality of blades that are arranged at equal intervals on the same circumference around the rotating shaft5and that are also arranged so as to extend along the radial direction (vertical direction inFIG. 8with respect to the plane of the drawing).

The first-stage turbine stator vanes404SV are turbine stator vanes disposed at positions facing the downstream-side end portions (bottom-side end portions inFIG. 8) of the tilted portions435with respect to the flow of combustion gas.

The first-stage turbine stator vanes404SV are formed with smaller sectional areas as compared with the first-stage turbine stator vanes4SV in the first embodiment and form airfoil shapes together with the tilted portions435.

Furthermore, trailing edges TE of the first-stage turbine stator vanes404SV are disposed at the same positions as the trailing edges TE of the first-stage turbine stator vanes4SV in the first embodiment, etc.

Unlike the first-stage turbine stator vanes4SV in the first embodiment, the cavities41inside which the cooling air is supplied and the cooling holes42from which the cooling air from the cavities41is made to flow out to the peripheries of the first-stage turbine stator vanes404SV are not formed in the first-stage turbine stator vanes404SV.

On the other hand, as shown inFIG. 8, the outflow channels146that communicate with the cooling channels145and from which the cooling air, after flowing through the cooling channels145, flows out along external surfaces of the first-stage turbine stator vanes404SV in the form of a film are provided between the first-stage turbine stator vanes404SV and the tilted portions435.

The outflow channels146are long, narrow slots that extend from the cooling channels145toward the outer side of the tilted portions435in the downstream direction (left-bottom direction inFIG. 8) of the flow of combustion gas.

Next, the flow of combustion gas from exits of the combustors403to the first-stage turbine stator vanes404SV, which is a feature of this embodiment, will be described.

Note that, because the general operation of the gas turbine401is the same as that in the first embodiment, a description thereof will be omitted.

As shown inFIG. 8, the combustion gas flows out from the tail pipes433of the combustors403and flows into the row of the first-stage turbine stator vanes404SV at the turbine portion404.

Specifically, the combustion gas that has flowed along the internal surfaces of the sidewalls434of the tail pipes433is deflected while flowing along the internal surfaces of the tilted portions435at the sidewalls434and the external surfaces of first-stage turbine stator vanes404SV.

At the same time, the cooling air that has flowed through the cooling channels145and cooled the tail pipes433and the tilted portions435flows out along the external surfaces of the first-stage turbine stator vanes404SV via the outflow channels146. The cooling air flows along the external surfaces of the first-stage turbine stator vanes404SV in the form of a film and cools the first-stage turbine stator vanes404SV.

With the above-described configuration, because the cross-sections of the tilted portions435at the sidewalls434have shapes that form airfoil shapes together with the first-stage turbine stator vanes404SV, as compared with the case in which the airfoil shapes are not formed, the flow of combustion gas can be effectively deflected.

Sixth Embodiment

Next, a sixth embodiment of the present invention will be described with reference toFIG. 9.

Although the basic configuration of a gas turbine of this embodiment is the same as that of the first embodiment, a communicating structure between the combustors and the turbine portion differs from that in the first embodiment. Therefore, only the communicating structure between the combustors and the turbine portion will be described in this embodiment by usingFIG. 9, and descriptions of other components, etc. will be omitted.

FIG. 9is a partially enlarged view for explaining the communicating structure between the combustors and the turbine portion in the gas turbine according to this embodiment.

Note that components that are the same as those in the first embodiment are given the same reference signs, and descriptions thereof will be omitted.

As shown inFIG. 9, combustors503in a gas turbine501of this embodiment differ from those in the first embodiment in the shapes of the end portions (bottom-side end portions inFIG. 9) of sidewalls534of tail pipes (pipe pieces)533closer to a turbine portion504.

Specifically, as shown inFIG. 9, the sidewalls534of the tail pipes533in the combustors503are provided with tilted portions535that deflect the flow of combustion gas leftward inFIG. 9.

The tilted portions535are end portions of the sidewalls534closer to the turbine portion504and are portions adjacent to the first-stage turbine stator vanes504SV. Furthermore, because the tilted portions535are formed by tilting the sidewalls534without other modifications, the thickness-wise size of the tilted portions535and the thickness-wise size of parts of the sidewalls534other than the tilted portions535are the same.

Furthermore, upstream-side end portions (top-side end portions inFIG. 9) of the tilted portions535with respect to the flow of combustion gas are at positions equivalent to the leading edges LE of the first-stage turbine stator vanes304SV in the fourth embodiment.

As shown inFIG. 9, the cooling channels145inside which cooling fluid, such as the cooling air, flows and that extend in the direction (top-bottom direction inFIG. 9) in which the combustion gas flows are provided between adjacent tail pipes533. Furthermore, the cooling channels145extend along the tilted portions535, between the tilted portions535at the sidewalls534.

End portions of the cooling channels145open at downstream-side end portions (bottom-side end portions inFIG. 9) of the tilted portions535at the sidewalls534.

On the other hand, as shown inFIG. 9, the turbine portion504of the gas turbine501in this embodiment is provided with the first-stage turbine stator vanes (turbine stator vanes)504SV.

The first-stage turbine stator vanes504SV form a turbine stage together with the first-stage turbine rotor blades4RB and generate a rotational driving force together with the first-stage rotor blades4RB from the combustion gas that has flowed into the turbine portion504. Furthermore, the first-stage turbine stator vanes504SV are a plurality of blades that are arranged at equal intervals on the same circumference around the rotating shaft5and that are also arranged so as to extend along the radial direction (vertical direction inFIG. 9with respect to the plane of the drawing).

The first-stage turbine stator vanes504SV are disposed at positions facing the downstream-side end portions (bottom-side end portions inFIG. 9) of the tilted portions535with respect to the flow of combustion gas.

The first-stage turbine stator vanes504SV are formed with a smaller sectional area as compared with the first-stage turbine stator vanes4SV, and a portion in the first-stage turbine stator vanes504SV where the thickness-wise size is the largest has the same thickness-wise size as the tilted portions535.

Furthermore, trailing edges TE of the first-stage turbine stator vanes504SV are disposed at the same positions as the trailing edges TE of the first-stage turbine stator vanes4SV in the first embodiment, etc.

Unlike the first-stage turbine stator vanes4SV in the first embodiment, the cavities41inside which the cooling air is supplied and the cooling holes42from which the cooling air from the cavities41is made to flow out to the peripheries of the first-stage turbine stator vanes504SV are not formed in the first-stage turbine stator vanes504SV.

On the other hand, as shown inFIG. 9, outflow channels146that communicate with the cooling channels145at the tilted portions535and from which the cooling air, after flowing through the cooling channels145, flows out along the peripheries of the first-stage turbine stator vanes504SV are provided between the first-stage turbine stator vanes504SV and the tilted portions535.

The outflow channels146are through-holes that extend from the cooling channels145toward the outer side of the tilted portions535in the downstream direction (left-bottom direction inFIG. 9) of the flow of combustion gas.

Next, the flow of combustion gas from exits of the combustors503to the first-stage turbine stator vanes504SV, which is a feature of this embodiment, will be described.

Note that, because the general operation of the gas turbine501is the same as that in the first embodiment, a description thereof will be omitted.

As shown inFIG. 9, the combustion gas flows out from the tail pipes533of the combustors503and flows into the row of the first-stage turbine stator vanes504SV at the turbine portion504.

Specifically, the combustion gas that has flowed along the internal surfaces of the sidewalls534of the tail pipes533is deflected while flowing along the internal surfaces of the tilted portions535at the sidewalls534and the external surfaces of first-stage turbine stator vanes504SV.

At the same time, the cooling air that has flowed through the cooling channels145and cooled the tail pipes533and the tilted portions535flows out along the external surfaces of the first-stage turbine stator vanes504SV via the outflow channels146. The cooling air flows along the external surfaces of the first-stage turbine stator vanes504SV in the form of a film and cools the first-stage turbine stator vanes504SV.

Note that the technical scope of the present invention is not limited to the above-described embodiments, and various modifications may be added thereto within a range that does not depart from the gist of the present invention.

For example, applications of the present invention are not limited to the above-described embodiments, the present invention may be applied to embodiments in which the above-described embodiments are appropriately combined; it is not particularly limited.

REFERENCE SIGNS LIST