JP4399199B2 - Regenerative heat exchanger structure of gas turbine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a regenerative heat exchanger structure that is optimal for preheating compressed air by heat exchange between exhaust gas from a gas turbine and compressed air from a compressor, and more specifically, the structure of a heat exchange core is simple. However, the present invention relates to a regenerative heat exchanger structure for a gas turbine that is excellent in energy conversion efficiency and has good workability during assembly and durability during use.
[0002]
[Prior art]
In recent years, gas turbine power generators have been reviewed and put into practical use as medium- and small-scale distributed power supplies or emergency private power generators, with the expansion of distributed energy systems in which a large number of medium and small power generation facilities are dispersed. Yes. The gas turbine is advantageous in that it can be mass-produced with a simple structure compared to other internal combustion engines, and that maintenance and inspection are easy.
[0003]
Usually, in order to improve the total power generation efficiency, the medium and small-sized gas turbine power generator employs a device configuration of a uniaxial regenerative cycle gas turbine. Specifically, a compressor, a turbine, and a generator are arranged on one axis, and combustion gas supplied from the combustor rotates the turbine and at the same time serves as a power source for the compressor and the generator that are connected coaxially.
[0004]
At this time, in order to reduce the loss of combustion gas energy, the combustion gas obtained by rotating the turbine exchanges heat with the air pressurized by the compressor so as to ensure energy conversion efficiency. That is, using the thermal energy possessed by the exhaust gas from the gas turbine, the combustion air for the combustor of the gas turbine is preheated to improve the conversion efficiency of the thermal energy into electric energy.
[0005]
For this reason, a regenerative heat exchanger that performs heat exchange between the exhaust gas of the gas turbine and the compressed air is necessary, and the performance greatly affects the performance of the gas turbine. Therefore, when designing a new gas turbine, a high-performance regenerative heat exchanger, that is, effective heat exchange with a small temperature difference, and when the gas turbine exhaust gas and compressed air circulate inside, Development of a regenerative heat exchanger with low loss is demanded.
[Patent Document 1]
JP 2003-049666 A
[Problems to be solved by the invention]
As described above, in order to develop a gas turbine with higher energy conversion efficiency, effective heat exchange is possible with a small temperature difference, and furthermore, high-performance regeneration with low pressure loss between the gas turbine exhaust and compressed air. Development of heat exchangers is an important issue. In order to cope with this, the present inventors have proposed a regenerative heat exchanger for a gas turbine in Patent Document 1 described above.
[0007]
The regenerative heat exchanger of the gas turbine proposed in Patent Document 1 is a regenerative heat exchanger that preheats compressed air by heat exchange between the exhaust of the turbine driven by the combustion gas generated by the combustor and the compressed air from the compressor. The turbine exhaust flow path and the compressed air flow path are formed in adjacent layers, and each flow path is configured to be filled with a linear heat transfer member.
[0008]
With this configuration, the flow velocity distribution in the flow channel approaches a uniform distribution, the flow velocity in the vicinity of the partition plate that divides the layered flow channel increases, and the turbine exhaust flow channel and the compressed air flow channel Heat transfer between the two can be promoted. Furthermore, since the linear heat transfer member increases the heat transfer area with the fluid, heat transfer can be further promoted. And since the shaping | molding process of a wire is easy, the regenerative heat exchanger of the gas turbine proposed by patent document 1 can be manufactured at low cost.
[0009]
However, in order to fully demonstrate these effects, the required characteristics at the time of construction and use of the regenerative heat exchanger of the gas turbine are properly grasped, and the regenerative heat exchange core is assembled based on the required characteristics, and the components used therefor are Design becomes important.
[0010]
The present invention has been made in view of such demands, and has a simple core structure, but is excellent in energy exchange efficiency, and has excellent workability during assembly and durability during use. It aims to provide a regenerative heat exchange structure.
[0011]
[Means for Solving the Problems]
In order to achieve the above-mentioned problems, the present inventors have studied the regenerative heat exchanger structure of various gas turbines. As a result, in order to reduce the size and increase the efficiency of the apparatus, each has a cylindrical shape and a different outer diameter. It is effective to use a plurality of separator sheets or rectangular separator sheets to form a heat exchange core portion in which a turbine exhaust flow path and a compressed air flow path are laminated. Focused on that. The present invention completed based on such attention focuses on the regenerative heat exchanger structure for a gas turbine described in (1) below .
[0012]
(1) A regenerative heat exchanger structure for a gas turbine that preheats the compressed air by exchanging heat between the exhaust of the turbine driven by the combustion gas generated by the combustor and the compressed air from the compressor, and has a cylindrical shape An inner tube and an outer tube are provided, and the turbine exhaust gas flow path and the compressed air flow path are formed by using a plurality of cylindrical separator sheets having different outer diameters. A closed compressed air flow port is provided in the exhaust flow path of the turbine, the compressed air flow path includes an end ring that seals both ends of the flow path, and the flow. the inlet side and outlet side of the road are provided with flow holes is 2 or more compressed air on the channel circumference, circulation holes of said compressed air inlet side or entry side flow holes and enter the, passage through the distribution for the port side After being introduced is heated, through the exit side flow holes or outlet side flow port and the exit-side flow holes in, the regeneration of the gas turbine, characterized in that to be supplied to the inner periphery of the core This is a heat exchanger structure (hereinafter simply referred to as “first heat exchanger structure”).
[0013]
According to the first heat exchanger structure, since the flow path is filled with the linear heat transfer member, the heat transfer area can be increased, and the flow path of the turbine exhaust and the flow path of the compressed air Can further promote heat transfer .
In the first heat exchanger structure, as a linear heat transfer member, each flow path of the turbine can be filled with a coil spring inserted into an inner tube or a separator sheet.
[0014]
As in the present invention, by using a coil spring as a heat transfer member to fill the flow path, the coil spring exhibits flexibility when the regenerative heat exchange core is assembled. Excellent.
[0015]
In use, when high-temperature combustion gas flows in, the flow path and the entire core have a non-uniform temperature distribution, and thermal stress is generated. Even in this case, due to the flexibility of the coil spring, it is possible to withstand severe fluctuations in heat load, and durability during use can be ensured.
[0016]
Furthermore, in the first heat exchanger structure, it is desirable to attach a linear heat transfer member, for example, a coil spring, to the inner tube and the separator sheet constituting the flow path by brazing. Since the linear coil spring can be reliably bonded to the inner tube and the separator sheet with a certain heat transfer area, the energy exchange efficiency can be improved.
[0017]
In the first heat exchanger structure, the compressed air circulation holes provided on the inlet side and the outlet side of the flow path of the compressed air are provided with a certain declination from the inlet side to the outlet side. It is desirable that the compressed air has a uniform flow .
[0018]
In addition to the first gas turbine regenerative heat exchanger structure of the present invention, as a regenerative heat exchanger structure capable of achieving downsizing and high efficiency of the apparatus, a second gas having the characteristics described in (2) below A turbine regenerative heat exchanger structure can be shown .
(2) The second gas turbine regenerative heat exchanger structure of the present invention preheats the compressed air by heat exchange between the exhaust of the turbine driven by the combustion gas generated by the combustor and the compressed air from the compressor. A regenerative heat exchanger structure for a gas turbine, each using a rectangular separator sheet, and forming a rectangular core in which the exhaust flow path and the compressed air flow path of the turbine are stacked and arranged. Is housed in a rectangular container, and each flow path is filled with a linear heat transfer member (hereinafter simply referred to as “second heat exchanger structure”).
[0019]
Also in the second heat exchanger structure, since the flow path is filled with linear heat transfer members, the heat transfer area can be increased, and the flow path of the turbine exhaust and the flow path of the compressed air Heat transfer can be further promoted. As a linear heat transfer member, a coil spring inserted into the separator sheet can be filled into the exhaust flow path and the compressed air flow path of the turbine.
[0020]
In the second heat exchanger structure, as described above, the coil spring is used as the heat transfer member to fill the flow path, so that the coil spring exhibits flexibility when the regenerative heat exchange core is assembled. Improved and workability is excellent. Even when there is a non-uniform temperature distribution in the flow path and the entire core during use, and thermal stress is generated, it can withstand severe thermal load fluctuations due to the flexibility of the coil spring. It is possible to ensure durability.
[0021]
In the second heat exchanger structure, it is desirable that the coil spring is attached to a separator sheet constituting the flow path by brazing. Since the linear coil spring can be reliably bonded to the separator sheet with a certain heat transfer area, the energy exchange efficiency can be improved.
[0022]
In the first heat exchanger structure and the second heat exchanger structure, the outer diameter, thickness, pitch, etc. of the coil spring filling the flow path of the turbine exhaust and the flow path of the compressed air are changed. By adjusting the packing density, it is possible to keep the resistance per unit area in each channel cross section constant and to prevent drift in the channel. As a result, the heat exchange performance in each flow path arranged in a stacked manner can be made uniform, and the performance can be maximized.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, with reference to the drawings, configuration examples of the “first heat exchanger structure” and the “second heat exchanger structure” of the present invention will be described in detail based on the case where a single-shaft regenerative cycle gas turbine is employed. explain.
(1) Configuration of First Heat Exchanger Structure FIG. 1 is a diagram for explaining the schematic configuration of the first heat exchanger structure and the flow of the fluid. The gas turbine shown in the figure is a single-shaft regeneration cycle gas turbine, and a compressor 4, a turbine 3, and a generator (not shown) are arranged on one shaft. As the turbine 3 is driven, the generator and the compressor 4 are also driven.
[0024]
Further, the gas turbine includes a combustor 2 that generates high-temperature combustion gas, a turbine 3 that is driven by the combustion gas C generated by the combustor 2, a compressor 4 that compresses air A, and the turbine 3. A regenerative heat exchange core 1 for exchanging heat between the exhaust D and compressed air B pressurized by the compressor 4 is provided.
[0025]
The air A supplied to the compressor 4 is pressurized to become compressed air B of about 250 ° C. and supplied to the regenerative heat exchange core 1. On the other hand, the turbine exhaust D is supplied to the regenerative heat exchange core 1 at a temperature of about 700 ° C. The compressed air B is preheated to about 650 ° C. by heat exchange in the regenerative heat exchange core 1.
[0026]
The compressed air B preheated in the regenerative heat exchange core 1 is introduced into the combustor 2, the fuel is combusted in the combustor 2, and the combustion gas C is heated to about 1000 ° C. to drive the turbine 3.
[0027]
In the regenerative heat exchange core 1 shown in FIG. 1, a flow path 5 for the exhaust D of the turbine and a flow path 6 for the compressed air B are stacked via a partition plate 7. Thus, by arranging the flow path 5 of the turbine exhaust D and the flow path 6 of the compressed air B coaxially with the rotating shaft of the turbine 3, the gas turbine of the present invention can be miniaturized.
[0028]
FIG. 2 is a diagram illustrating a configuration example of the regenerative heat exchange core according to the present invention and the flow of turbine exhaust and compressed air. The regenerative heat exchange core 1 of the present invention uses a separator sheet 12 having different outer diameters to form a core in which a turbine exhaust flow path 5 and a compressed air flow path 6 are stacked and accommodated. An inner tube 11 and an outer tube 13 are provided.
[0029]
The exhaust D that has driven the turbine 3 collides with the guide lid 9 provided at the end, and then is dispersed in the circumferential direction to become a uniform flow, and is introduced into the exhaust flow path 5 of the turbine that is stacked coaxially. . After that, it flows while exchanging heat with the adjacent compressed air flow path 6 and is discharged out of the regenerative heat exchange core 1.
[0030]
On the other hand, the compressed air B exiting the compressor 4 is introduced into the innermost compressed air flow path 6 through a flow hole 14 provided on the inlet side of the flow path 6. In order to introduce the compressed air B into the upper-layer passage 6, a compressed air circulation port 15 is provided in the turbine exhaust passage 5, and the compressed air B passes through the circulation port 15. , Introduced into the upper passage 6.
[0031]
The compressed air B introduced into the passage 6 circulates while exchanging heat with the exhaust passage 5 of the adjacent turbine, and passes through the circulation port 15 or the circulation hole 14 provided on the outlet side of the passage 6. And supplied to the inner periphery of the regenerative heat exchange core 1. Thereafter, the heated compressed air B is introduced into a combustor (not shown), and the fuel is combusted to become high-temperature combustion gas.
[0032]
In order to circulate the compressed air B through the regenerative heat exchange core 1 and supply it to the inner peripheral portion thereof, the compressed air flow path 6 has an end ring 17 and a compressed air flow hole 14 for sealing both ends of the flow path. It is arranged. Further, in order to allow the compressed air B to flow between the innermost layer flow path 6 and the upper layer passage 6, a sealed distribution port 15 is provided in the turbine exhaust flow path 5.
[0033]
FIG. 3 is a view for explaining the inner tube and other components constituting the inner peripheral surface of the turbine. In the regenerative heat exchange core according to the present invention, the coil spring 16 can be used as a heat transfer member. Therefore, as shown in FIG. The flow path 5 may be filled.
[0034]
As shown in FIG. 3A, by inserting the coil spring 16 and filling the flow path, the heat transfer area can be increased, and the thermal efficiency of the regenerative heat exchange core can be improved.
[0035]
Furthermore, storage property can be improved when the regenerative heat exchange core is assembled, and the workability is excellent. Further, it can withstand the generation of thermal stress during use, and durability can be ensured.
[0036]
Compressed air circulation holes 14 are provided at both the inlet and outlet ends of the inner tube 11. And as shown in FIG.3 (b), in order to seal the compressed air which distribute | circulated this circulation hole 14 and distribute | circulate the inside of the flow path of exhaust of a turbine, the port 15 for distribution is attached. By flowing through the flow port 15, the compressed air can flow between the innermost flow path and the upper flow path.
[0037]
The coil spring 16 shown in FIG. 3A has a ring shape, and a large number of coil springs are mounted when the flow path is filled. However, the present invention is not limited to the ring-shaped coil spring, and a spiral coil spring 16 ′ can be used as shown in FIG.
[0038]
FIG. 4 is a diagram for explaining the separator sheet 12 and other components constituting each flow path of the turbine. Similarly to FIG. 4, since the coil springs 16 and 16 ′ can be used as the heat transfer members, the coil springs 16 and 16 ′ can be inserted into the separator sheet 12 to fill the flow path 6 of the compressed air.
[0039]
In order to make the compressed air flow path 6 hermetically sealed, end rings 17 that are sealed at both ends of the compressed air flow path are attached to both end faces of the inner tube 11 and the separator sheet 12. The separator sheet 12 is provided with a flow hole 14 for introducing compressed air.
[0040]
FIG. 5 is a diagram illustrating the configuration of the outer tube that constitutes the outer peripheral surface of the turbine. The outer tube 13 accommodates the core in which the exhaust gas flow path of the turbine and the compressed air flow path are stacked, and constitutes the appearance of the regenerative heat exchange core of the present invention.
[0041]
FIG. 6 is a diagram showing the overall configuration of the regenerative heat exchange core of the present invention. As described above, the regenerative heat exchange core 1 of the present invention is arranged coaxially with the rotating shaft of the turbine, so that the gas turbine is reduced in size and efficiency.
[0042]
In FIG. 6, compressed air circulation holes 14 are provided on the inlet side and the outlet side of the compressed air flow path, and four are provided on the circumference of the flow path. Furthermore, the compressed air circulation holes 14 provided on the entry side and the exit side are arranged with a deviation angle θ. The reason why the deviation angle θ is provided is to prevent a deviation flow in the flow path of the compressed air and to make the flow uniform.
(2) Configuration of Second Heat Exchanger Structure FIG. 7 is a diagram for explaining the schematic configuration of the second heat exchanger structure and the flow of the fluid. As in FIG. 1, the gas turbine shown in FIG. 7 is also a single-shaft regenerative cycle gas turbine, in which a compressor 4, a turbine 3, and a generator (not shown) are arranged on a single shaft. Along with this, the generator and the compressor 4 are also driven.
[0043]
7 includes a combustor 2 that generates high-temperature combustion gas, a turbine 3 that is driven by the combustion gas C generated by the combustor 2, a compressor 4 that compresses air A, A regenerative heat exchange core 1 in which flow paths of exhaust D of the turbine 3 and compressed air B pressurized by the compressor 4 are stacked is provided.
[0044]
The air A supplied to the compressor 4 becomes compressed air B and is supplied to the regenerative heat exchange core 1. On the other hand, the turbine exhaust D is supplied to the regenerative heat exchange core 1 at a temperature of about 700 ° C. The compressed air B is preheated to about 650 ° C. by heat exchange in the regenerative heat exchange core 1. The compressed air B preheated in the regenerative heat exchange core 1 is introduced into the combustor 2, the fuel is combusted in the combustor 2, and the combustion gas C is heated to about 1000 ° C. to drive the turbine 3.
[0045]
The regenerative heat exchange core 1 shown in FIG. 7 has a flow path for the exhaust D of the turbine and a flow path for the compressed air B stacked on each other via a separator sheet, and these are containers constituting the appearance of the regenerative heat exchange core. Is housed inside. The exhaust D that has driven the turbine 3 is dispersed at the end of the regenerative heat exchange core 1 to form a uniform flow, and after being introduced into the exhaust flow path of the stacked turbine, the adjacent compressed air flow path and heat It is distributed while being exchanged and discharged out of the regenerative heat exchange core 1.
[0046]
On the other hand, the compressed air B preheated by the compressor 4 is introduced into the flow path of the compressed air so as to counter-flow with the exhaust D of the turbine after passing through the distributor portion 1a on the inlet side, and is stacked up and down. It circulates while exchanging heat with the flow path of the exhaust D of the turbine. Thereafter, the compressed air B gathered through the outlet distributor 1b is introduced into the combustor 2 and becomes high-temperature combustion gas C to drive the turbine 3.
[0047]
FIG. 8 is a diagram showing a configuration example of a regenerative heat exchange core that is stacked and arranged using rectangular separator sheets used in the second heat exchanger structure. As shown in the figure, in the regenerative heat exchange core 1 of the second heat exchanger structure, when the exhaust air D of the turbine and the compressed air B from the compressor are heat-exchanged to preheat the compressed air B, The flow path 5 for the turbine exhaust and the flow path 6 for the compressed air are formed in layers by providing a separator sheet (partition plate) 7 so that each of the flow paths 5 and 6 is filled with a linear heat transfer member 8. It is configured.
[0048]
Similarly to the first heat exchanger structure, the coil springs 16 and 16 ′ can be used as the heat transfer member 8. Therefore, the coil springs 16 and 16 ′ are inserted into the separator sheet 7 so that the flow of the exhaust gas from the turbine can be reduced. The channel 5 and the compressed air channel 6 can be filled.
[0049]
With this configuration, the flow velocity distribution in the flow passages 5 and 6 approaches a uniform distribution, the flow velocity in the vicinity of the separator sheet 7 that divides the layered flow passage increases, and the turbine exhaust flow passage 5 is compressed. Heat transfer with the air flow path 6 can be promoted. Furthermore, since the coil springs 16 and 16 ′ used as the linear heat transfer member 8 increase the heat transfer area with the fluid, the heat transfer can be further promoted.
[0050]
In the “first heat exchanger structure” and the “second heat exchanger structure” of the present invention, drift may occur in each flow path of the regenerative heat exchange core. For this reason, by increasing the density of the coil springs to be inserted at locations where the circulation density of turbine exhaust and compressed air is likely to increase, the compressed air circulation density is reduced to the extent possible in the compressed air flow path. It is possible to adjust the flow to be uniform by suppressing the occurrence of drift.
[0051]
【The invention's effect】
According to the regenerative heat exchanger structure of the gas turbine of the present invention, the regenerative heat exchange core is designed based on the required characteristics at the time of construction and use. In addition to being excellent, the workability during assembly and the durability during use are also good.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a schematic configuration of a “first heat exchanger structure” of the present invention and a flow of fluid thereof.
FIG. 2 is a diagram for explaining a configuration example of a regenerative heat exchange core according to the present invention and the flow of turbine exhaust and compressed air.
FIG. 3 is a view for explaining an inner tube and other components constituting an inner peripheral surface of a turbine.
FIG. 4 is a diagram illustrating a separator sheet and other components that constitute each flow path of the turbine.
FIG. 5 is a diagram illustrating a configuration of an outer tube that forms an outer peripheral surface of a turbine.
FIG. 6 is a diagram showing an overall configuration of a regenerative heat exchange core according to the present invention.
FIG. 7 is a diagram for explaining a schematic configuration of the “second heat exchanger structure” of the present invention and the flow of the fluid.
FIG. 8 is a diagram showing a configuration example of a regenerative heat exchange core that is stacked and arranged using rectangular separator sheets used in the second heat exchanger structure.
[Explanation of symbols]
1: Regenerative heat exchanger, Regenerative heat exchange core 2: Combustor 3: Turbine 4: Compressor 5: Exhaust flow path 6: Compressed air flow path 7: Partition plate, separator sheet 8: Wire 9: Guide lid 11: Inner tube 12: Separator sheet 13: Outer tube 14: Distribution hole 15: Distribution port 16: Coil spring 17: End ring

Claims (5)

A regenerative heat exchanger structure for a gas turbine that preheats the compressed air by heat exchange between the exhaust of the turbine driven by the combustion gas generated by the combustor and the compressed air from the compressor,
An inner tube and an outer tube arranged in a cylindrical shape, and a plurality of separator sheets having a cylindrical shape and different outer diameters are formed on the inner tube and the outer tube. Contains a stacked core,
A closed compressed air circulation port is provided in the exhaust passage of the turbine,
An end ring that seals both ends of the flow path is disposed in the flow path of the compressed air, and two or more compressed air circulation holes are disposed on the circumference of the flow path on the inlet side and the outlet side of the flow path. And
After the compressed air that has been heated is introduced into the passage through the flow holes or inlet side flow port of the communication holes and the inlet side of the inlet side, outlet side flow holes or outlet side flow port and out of, the A regenerative heat exchanger structure for a gas turbine, characterized in that the regenerative heat exchanger structure is supplied to the inner peripheral portion of the core through the flow hole on the side.   The compressed air flow holes provided on the inlet side and the outlet side of the compressed air flow path are provided with a certain declination from the inlet side to the outlet side, and the compressed air is uniformly distributed. The regenerative heat exchanger structure for a gas turbine according to claim 1, wherein the regenerative heat exchanger structure is a flow.   The turbine exhaust flow path and the compressed air flow path are filled with linear heat transfer members, and the heat transfer members are inserted into the inner tube and the separator sheet in the respective flow paths of the turbine. The regenerative heat exchanger structure for a gas turbine according to claim 1 or 2, wherein the coil spring is filled.   The regenerative heat exchanger structure for a gas turbine according to claim 2 or 3, wherein the linear heat transfer member is attached to the inner tube and the separator sheet by brazing.   Adjusting the packing density of coil springs filled as linear heat transfer members in the exhaust flow path of the turbine and the compressed air flow path prevents drift in the flow path and improves heat exchange performance. The regenerative heat exchanger structure for a gas turbine according to claim 3 or 4, wherein the regenerative heat exchanger structure can be realized.

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