JPH07224685A - Silencer for gas turbine - Google Patents

Abstract

PURPOSE:To provide such a splitter type silencer for a gas turbine that saves works such as reduction in pressure loss of fluid gas, reduction in stress generated due to thermal extension difference between a porous board of the silencer panel and a frame surrounded by an acoustic material (thermal insulation material), inspection and repair, etc., for maintenance of the splitter type silencer. CONSTITUTION:In a splitter type silencer provided with a plurality of silencer panels in series along the gas flowing direction in an intake duct and an exhaust duct for a gas turbine, a cover 20 for adjusting an aperture is attached to the rear end of an upper stream side silencer panel 8a by setting a value to the aperture between the upper stream side silencer panel 8a and a downstream side silencer panel 8b in such a state that the aperture becomes zero due to thermal expansion in driving.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine silencer provided in an intake / exhaust portion of a gas turbine.

[0002]

2. Description of the Related Art In recent years, gas turbines have grown in size with the development of highly efficient combined cycle power plants, and the amount of intake and exhaust air has increased. In addition, as the inlet temperature of the gas turbine is raised to increase efficiency,
As the exhaust gas temperature rises, the gas temperature at the gas turbine outlet rises to over 600 ° C.

With the increase in capacity of gas turbines, noise and energy level at the gas turbine outlet become a big problem (reaching 130 dB at the gas turbine outlet), and a large, low-volume exhaust silencer is attached to the gas turbine outlet. Came. However, it has been pointed out that the reliability with respect to temperature rise and upsizing is lowered, and further improvement in durability has been demanded.

In addition, the conventional gas turbine has a high role as an emergency power supply facility, but a highly efficient combined cycle power plant combining a steam turbine and a gas turbine is a conventional thermal power plant or a nuclear power plant. Since it is more efficient and more excellent in start-up characteristics than the above, it tends to be used for load-following DSS (daily start-stop) operation.

FIG. 17 exemplifies the structure of a combined cycle power plant. The exhaust gas of the gas turbine 1 is introduced into the exhaust heat recovery boiler 3 through the silencer 2, and the steam turbine 4 is driven by the steam generated in the exhaust heat recovery boiler 3. Generators 5 and 6 are connected to the gas turbine 1 and the steam turbine 4, respectively, and electric power is generated by the outputs of the turbines 1 and 4. 3a is a chimney for discharging waste gas. Such a gas turbine 1
The exhaust silencer 2 is required to have a structure that can withstand thermal expansion and contraction due to daily start and stop, and exhaust gas flow having a large flow velocity distribution.

The structure of a conventional silencer is shown in FIGS.
Is illustrated in. This silencer 2 is a splitter type silencer, and as shown schematically in FIG. 18 and FIG.
A silencer duct 7 forming a part of the exhaust duct is provided with a plurality of flat plate-like silencer panels 8 arranged in parallel in a direction orthogonal to the gas flow.

As shown in FIG. 20, the silencer panel 8 has a streamlined bull nose 8B at the front end of a flat plate-shaped main body 8A.
Is provided. As shown in FIGS. 21 to 23, the silencer panel 8 has an assembly structure in which a perforated plate 10 in which a large number of through holes 9 are formed in a heat resistant steel plate is attached to a lattice-shaped frame 11 in a tile shape. A sound absorbing material block 12 is filled in the frame 11.

The sound absorbing material block 12 is shown in FIG.
As shown in (B), the sound absorbing material 13 has a block structure protected by a cloth 14 and a mat 15, and is covered with a wire mesh 16 for preventing scattering and sewn with a stainless wire 16a.

Incidentally, as a document relating to the prior art,
"New revision / pollution prevention guidelines [Noise / Vibration]
Published by the Industrial Pollution Control Association or the Noise Reduction Handbook edited by the Japan Acoustical Materials Association published by Gihodo.

[0010]

By the way, in recent years, for the purpose of increasing the size of a gas turbine and reducing noise due to environmental problems, in recent years there has been a strong demand to increase the length of the silencer panel 8 in the gas flow direction. Due to size restrictions in manufacturing and transportation, it is necessary to divide the silencer panel 8 and the silencer duct 7 into a plurality in the gas flow direction.

FIGS. 25 and 26 show a splitter type silencer structure to meet such a demand. The upstream silencer panel 8a and the downstream silencer panel 8b, which are divided in the gas flow direction, are fastened to the upstream silencer duct 7a and the downstream silencer duct 7b, respectively, through the stoppers 17 for preventing slippage. There is.

However, in this case, a gap Z is formed between the upstream silencer panel 8a and the downstream silencer panel 8b.
Occurs.

Due to this gap Z, as shown in FIG.
Vortices are generated in the gas flow inside the silencer, which causes the pressure loss to rise.

FIG. 28 shows the temperature change of each part when the exhaust gas of the gas turbine flows into the splitter type silencer according to the prior art. In FIG. 28, “a” shows a change in gas temperature at the gas turbine outlet, that is, a change in exhaust gas temperature flowing into the silencer panel 8. b shows the change of the temperature of the perforated plate 10 welded and fixed to the surface of the silencer panel 8. Reference character c indicates a change in temperature of the frame 11 forming the silencer panel 8. d indicates the temperature difference between the porous plate 10 and the frame 11.

When the gas turbine is started, the temperature of the exhaust gas at the gas turbine outlet rises rapidly to 650 ° C. in a short time.
Rise to. The temperature of the perforated plate 10 rises slightly later than the exhaust gas temperature at the gas turbine outlet because of the heat capacity of various members installed in the gas passage and the perforated plate itself.

Further, the frame 11 of the silencer panel 8
The temperature rises further later than the perforated plate 10 due to the filling of the sound absorbing material block 12 and the small contact area with the gas. As a result, a temperature difference occurs between the porous plate 10 and the frame 11 due to the difference in temperature rising rate. Since the perforated plate 10 and the frame 11 are fixed by welding, the difference in thermal expansion due to this temperature difference cannot be released, and the surface of the perforated plate 10 is cracked or the perforated plate 10 is deformed and wrinkled. There was a problem such as.

Therefore, for the purpose of reducing the thermal expansion difference due to the above-mentioned temperature difference and the purpose of improving the noise reduction characteristic of the silencer, the thickness of the silencer panel 8 has recently become smaller than the conventional one.

On the other hand, the gas passage between the silencer panels is as narrow as about half the thickness of the silencer panel.
Since there is a design of 0 mm or less, there is a problem that a worker for the purpose of inspection and repair for maintenance cannot enter the gas passage between the silencer panels.

The present invention has been made in view of the above circumstances, and is achieved by reducing the pressure loss of flowing gas and by the difference in thermal expansion between the perforated plate of the silencer panel and the frame surrounded by the sound absorbing material (heat insulating material). An object of the present invention is to provide a splitter-type gas turbine silencer that can reduce the stress generated and can reduce the inspection and repair work for maintenance of the splitter-type silencer.

[0020]

In order to achieve the above object, the invention of claim 1 has a plurality of silencer panels arranged in series along the gas flow direction in an intake duct or an exhaust duct of a gas turbine. In the splitter-type silencer, a gap adjusting cover is set on the trailing edge of the upstream silencer panel by setting the gap between the upstream silencer panel and the downstream silencer panel to a value such that the gap becomes zero due to thermal expansion during operation. Is installed.

According to a second aspect of the present invention, instead of the cover of the first aspect, a cover for adjusting a gap is attached to the front edge of the downstream silencer panel, and the gap between this cover and the upstream silencer panel is zero due to thermal expansion during operation. It is characterized by setting to a value such that

According to the third aspect of the present invention, the rear edge portion of the upstream silencer panel is formed in a concave shape, the front edge portion of the downstream silencer panel is formed in a convex shape, and both silencer panels are fitted to each other. The feature is that the gap as the flow path between the panels is set to zero.

According to a fourth aspect of the present invention, there is provided a splitter type silencer provided in an intake / exhaust duct of a gas turbine,
In a structure in which a silencer panel is formed by a frame formed in a lattice shape, a sound absorbing material filled in the frame, and a perforated plate which is a cover of the sound absorbing material attached to the frame, the perforated plate is provided in the frame. The perforated plate is slidably clamped by a groove-shaped pressing member having a length that is slidable with respect to the frame and is held together by a plurality of studs fixed to the frame. The plate has a hole for loosely inserting the stud in the stud insertion portion, and is provided with a thermal expansion absorption portion during operation of the gas turbine.

According to a fifth aspect of the present invention, in a silencer for a gas turbine of a splitter type in which a silencer panel is inserted and arranged in a silencer duct, the silencer panel can be inserted and pulled out by a guide rail on the inner surface of another duct adjacent to the silencer duct. A hoisting device for supporting and for pulling out the silencer panel is disposed in the other duct.

According to a sixth aspect of the present invention, in a splitter type gas turbine silencer in which a silencer panel is inserted and arranged in a silencer duct, a plurality of inspection holes are formed in the silencer duct, and the silencer panel is provided from an outer peripheral surface side of the silencer duct. It is characterized in that a TV camera device for inspection can be inserted on the side.

[0026]

According to the present invention, the gap adjusting means is provided so that the gap between the plurality of silencer panels divided in series in the gas flow direction becomes zero during operation. The vortices between the silencer panels are suppressed, and the pressure loss due to the vortex flow is reduced.

According to the fourth aspect of the invention, since the frame constituting the silencer panel can slide on the perforated plate, thermal expansion due to heating during operation can be absorbed to reduce stress.

According to the invention of claim 5, a plurality of mounting supports for mounting the hoisting device and a plurality of removable guide rails are provided in the duct, so that the duct of the silencer panel is provided. It will be possible to pull it out, and it will be possible to repair the silencer panel in a short period of time.

According to the sixth aspect of the present invention, in the inspection work and repair work accompanying maintenance, the accuracy of the inspection work by the small television camera device at the portion which cannot be approached can be improved.

[0030]

Embodiments of the present invention will be described below with reference to the drawings. Note that the same parts as those of the conventional configuration are shown in FIGS.
The description will be made by using the same reference numeral as 7.

Embodiment 1 (FIGS. 1 to 5) As shown in FIGS. 1 to 4, the silencer 2 of this embodiment includes an upstream silencer tact 7a and a downstream silencer duct 7b which are exhaust ducts of a gas turbine. Inside thereof, an upstream side silencer panel 8a and a downstream side silencer panel 8b are arranged in series along the gas flow direction. Each silencer panel 8a, 8b is connected to each silencer duct 7a, 7 via a silencer panel stopper 17.
The gap adjusting cover 20 is fixed between the silencer panels 8a and 8b.

The gap adjusting cover 20 has a U-shaped cross section, and its open end side is fixed to the rear edge of the upstream silencer panel 8a by welding or the like. A constant initial gap x is set between the cover 20 and the front edge of the downstream silencer panel 8b. The gap x is set to a value that becomes almost zero due to thermal expansion of the material during gas turbine operation.

According to this structure, the gap x between the upstream silencer panel 8a and the downstream silencer panel 8b becomes substantially zero by the gap adjusting cover 20 during operation of the gas turbine. As shown
It is possible to reduce or eliminate the vortex flow of gas due to the gap between the upstream and downstream silencer panels 8a and 8b which has been conventionally generated.

Therefore, according to this embodiment, it is possible to reduce the pressure loss caused by the vortex flow due to the gap between the silencer panels 8a and 8b divided on the upstream and downstream sides.

Embodiment 2 (FIGS. 6 and 7) This embodiment is different from Embodiment 1 in that the gap adjusting cover 20 is attached to the front edge of the downstream silencer panel 8b, and the cover 20 and the upstream side are attached. The gap y between the silencer panel 8a and the silencer panel 8a is set to zero during operation. The other structure is substantially the same as that of the first embodiment.

With such a configuration, as described above,
Generation of gas vortex between the silencer panels 8a and 8b during operation can be prevented, and pressure loss due to the vortex can be reduced.

Embodiment 3 (FIG. 8) In this embodiment, the upstream silencer panel 8a is integrally provided with a trailing edge cover 21 having a concave cross-section that opens rearward, and the downstream silencer panel 8b has a narrow width. That is, the front edge having a convex cross section is fitted to the rear edge cover 21. As a result, the gap between the silencer panels 8a and 8b in the gas flow direction is eliminated, and the generation of gas vortex is prevented.

With this structure, as in the above-described embodiments, the pressure loss due to the vortex flow due to the gap between the front and rear silencer panels 8a and 8b can be reduced.

Embodiment 4 (FIGS. 9 to 12) This embodiment is intended to reduce the stress due to the difference in thermal expansion of the constituent materials for one silencer panel structure.

9 and 10 show the construction of the upstream silencer panel 8a. This silencer panel 8a
Is a sound absorbing material block 1 on a frame 11 formed in a lattice shape.
2 is filled, and a plurality of perforated plates 10 are attached to the upper and lower sides and front and rear sides and fixed (see FIG. 21). In this structure, as shown in FIG. 10, the perforated plate 10 is slidable in contact with the frame 11 at a sliding portion 11a. Then, as shown in FIG. 11, each perforated plate 10 is provided with a horizontally long presser piece 23 made of channel steel having a length that is held together by a plurality of studs 22 fixed to the frame 11 so that the frame 11 It is sandwiched between and by a washer 24. And each perforated plate 1
No. 0 has a hole 25 as a long hole or a large hole in the stud insertion portion, which has a margin for stud floating, and is set as a thermal expansion absorber during gas turbine operation. In addition, a hole 26 for absorbing thermal expansion is also formed in the pressing member 23.

Further, as shown in FIG. 12, holes 27 for absorbing heat expansion are formed at the end portions which are the joining portions of the perforated plates 10 in the vertical and horizontal directions, and sliding in the superposed state is possible. It is possible. As a result, the contact surface of the porous plate 10 with the frame 11 does not buckle, and sliding due to thermal deformation is allowed. The stud 22 is welded and fixed to the frame 11 and the washer 24.

With this structure, the perforated plate 10 that is directly exposed to the exhaust gas can expand and contract following the exhaust gas temperature during the starting and stopping of the gas turbine. That is, the frame 11 surrounded by the sound absorbing material block 12 is the porous plate 1
0 will not be constrained, and the perforated plate 10 will be the frame 11
It is possible to reduce the thermal stress due to the difference in thermal expansion generated between the porous plate 10 and the frame 11 by sliding on the contact surface with.

Embodiment 5 (FIGS. 13 to 15) In this embodiment, as shown in FIGS. 13 to 15, the silencer panel 8 has upper and lower guide rails 29 on the inner surface of another duct 28 adjacent to the silencer duct 7. It is accommodated by 30 so that it can be inserted and withdrawn.

A winding device 31 for pulling out the silencer panel 8 is provided in the adjacent duct 28 on a mounting support 32 via a fastener 33 such as a bolt or a nut.

Then, as shown in FIGS. 14 and 15, the silencer panel 8 can be pulled out through the chain 35 with the hook 34 attached to the hoisting device 31 and the band 36 hooked on the chain 35.

According to this embodiment having such a structure, even in the case of the split type silencer in which the gas passage portion between the silencer panels 8 is narrow and it is impossible for the worker for inspection and repair to come close to the inside of the adjacent duct 28. With silencer panel 8
By pulling out, inspection and repair work can be easily performed.

Embodiment 6 (FIG. 16) In this embodiment, as shown in FIG. 16, a plurality of inspection holes 37 are formed in the silencer duct 7, and a small television is provided from the outer peripheral surface side of the silencer duct 7 to the silencer panel 8 side. The camera device 38 can be inserted. Multiple inspection holes 3
7 is a hole of a guide cylinder 39 which is located in the gas passage between the silencer panels 8 and is attached to the silencer duct 7, and the small television camera device 38 is introduced into the duct via a cable 40. Cable 40 is amplifier 41
It is connected to the recorder 42 and the image receiver 43 via.

According to this structure, even in the split type silencer in which the gas passage portion between the silencer panels is narrow and it is impossible for the inspector to approach for inspection, the inspector for inspection is provided in the silencer duct 7. It is not necessary to enter, and it is possible to perform inspection safely and in a short time from the outer peripheral surface side of the silencer duct 7.

[0049]

As described above, according to the inventions of claims 1 to 3, the gap is adjusted so that the gap between the plurality of silencer panels divided in series in the gas flow direction becomes zero during operation. Since the means is provided, the vortex of the gas flow between the silencer panels is suppressed, and the pressure loss due to the vortex flow is reduced.

Further, according to the invention of claim 4, since the frame constituting the silencer panel can slide on the perforated plate, thermal expansion due to heating during operation can be absorbed to reduce stress.

Further, according to the invention of claim 5, a plurality of mounting supports for mounting the hoisting device and a plurality of detachable guide rails are arranged in the duct, whereby the duct of the silencer panel is provided. It is possible to pull it out inside, and it is possible to repair the silencer panel in a short period of time.

Furthermore, according to the sixth aspect of the present invention, in the inspection work and the repair work accompanying the maintenance, the accuracy of the inspection work by the small television camera device at the portion which cannot be approached can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of the present invention.

FIG. 2 is an enlarged side view showing a portion A of FIG.

FIG. 3 is a plan view showing a panel installation state of the embodiment.

FIG. 4 is a side view of FIG.

FIG. 5 is an operation explanatory view (plan view) of the embodiment.

FIG. 6 is a perspective view showing a second embodiment of the present invention.

FIG. 7 is a side view showing an enlarged part B of FIG.

FIG. 8 is an explanatory view (plan view) of the operation of the embodiment.

FIG. 9 is a side view of the entire panel showing a third embodiment of the present invention.

FIG. 10 is a sectional view taken along line CC of FIG.

11 is an enlarged cross-sectional view taken along line DD of FIG.

12 is an enlarged cross-sectional view taken along line EE of FIG.

FIG. 13 is a perspective view showing a fourth embodiment of the present invention.

FIG. 14 is an explanatory view (side view) of the operation of the embodiment.

FIG. 15 is an explanatory view (perspective view) of the operation of the embodiment.

FIG. 16 is a configuration diagram showing a fifth embodiment of the present invention.

FIG. 17 is a diagram showing a configuration of a gas turbine with a silencer in a combined cycle.

FIG. 18 is a view showing a conventional example of a silencer, taken along the line F-F in FIG. 17.

19 is a cross-sectional view taken along the line GG of FIG.

FIG. 20 is a perspective view showing a conventional silencer panel.

FIG. 21 is an exploded perspective view showing a conventional silencer panel.

FIG. 22 is an enlarged side view showing a conventional silencer panel.

23 is a cross-sectional view taken along the line HH of FIG.

24 (A) and 24 (B) are perspective views showing a sound absorbing material block in a conventional example.

FIG. 25 is a plan view showing an arrangement configuration of a silencer panel in a conventional example.

FIG. 26 is a side view of FIG. 25.

FIG. 27 is an operation explanatory view (plan view) of the conventional example.

FIG. 28 is a graph showing characteristics of a conventional example.

[Explanation of symbols]

 1 Gas Turbine 2 Silencer 3 Exhaust Heat Recovery Boiler 3a Chimney 4 Steam Turbine 5,6 Generator 7 Silencer Duct 7a Upstream Silencer Duct 7b Downstream Silencer Duct 8 Silencer Panel 8A Flat Body 8B Bullnose 9 Through Hole 10 Perforated Plate 11 Frame 12 Sound absorbing material block 13 Sound absorbing material 14 Cross 15 Mat 16 Wire mesh 16a Stainless wire 17 Stopper 20 Cover 21 Rear edge cover 22 Stud 23 Presser hardware 24 Washer 25, 26, 27 hole 28 Duct 29, 30 Guide rail 31 Winding device 32 Support stand 33 Tightening tool 34 Hook 35 Chain 36 Band 37 Inspection hole 38 Small TV camera device 39 Guide tube 40 Cable 41 Amplifier 42 Recorder 43 Receiver

Claims (6)

[Claims] 1. A splitter-type silencer in which a plurality of silencer panels are arranged in series in an intake duct or an exhaust duct of a gas turbine along a gas flow direction,
The gap between the upstream silencer panel and the downstream silencer panel is set to a value such that the gap becomes zero due to thermal expansion during operation, and a cover for adjusting the gap is attached to the trailing edge of the upstream silencer panel. Silencer for gas turbine. 2. A cover for adjusting the gap is attached to the front edge of the downstream silencer panel in place of the cover of claim 1, and the gap between the cover and the upstream silencer panel becomes zero due to thermal expansion during operation. A silencer for a gas turbine characterized by being set to. 3. A rear edge portion of the upstream silencer panel is formed in a concave shape, and a front edge portion of the downstream silencer panel is formed in a convex shape, and these silencer panels are fitted to each other, so that the space between the panels is reduced. A silencer for a gas turbine, characterized in that the gap as a flow path is set to zero. 4. A splitter type silencer provided in an intake / exhaust duct of a gas turbine, the frame being formed in a lattice shape, a sound absorbing material filled in the frame, and a sound absorbing member attached to the frame. In a silencer panel configured with a perforated plate that serves as a cover of a material, the perforated plate is slidable with respect to the frame,
In addition, the perforated plate is slidably held by a groove-shaped pressing metal having a length that is held collectively by a plurality of studs fixed to the frame, and each perforated plate has the stud insertion portion. A silencer for a gas turbine, characterized in that a thermal expansion absorption portion is set during operation of the gas turbine by having a hole for loosely inserting a stud therein. 5. A splitter-type gas turbine silencer having a silencer panel inserted and arranged in a silencer duct, wherein the silencer panel is supported by a guide rail on the inner surface of another duct adjacent to the silencer duct, A silencer for a gas turbine, wherein a winding device for pulling out the silencer panel is arranged in the other duct. 6. A silencer for a gas turbine of a splitter type having a silencer panel inserted and arranged in a silencer duct, wherein a plurality of inspection holes are formed in the silencer duct, and the silencer duct is inspected from the outer peripheral surface side to the silencer panel side. A silencer for a gas turbine, which can be inserted with a television camera device.