JP6104657B2 - Exhaust system - Google Patents

Description

  The present invention, for example, in a gas turbine that supplies fuel to compressed high-temperature, high-pressure air and burns it, supplies the generated combustion gas to the turbine to obtain rotational power, and discharges the exhaust gas burned in the gas turbine. The present invention relates to an exhaust device for discharging.

  The gas turbine is composed of a compressor, a combustor, and a turbine, and the air taken in from the air intake port is compressed by the compressor to become high-temperature / high-pressure compressed air. The fuel is supplied and burned, and the high-temperature and high-pressure combustion gas drives the turbine, and the generator connected to the turbine is driven. In this case, the turbine is configured by alternately arranging a plurality of stationary blades and moving blades in the vehicle interior, and drives the moving blades with combustion gas to rotate the output shaft to which the generator is connected. ing. The combustion gas that has driven the turbine becomes exhaust gas, passes through the exhaust duct, and is discharged from the chimney to the atmosphere.

  Such an exhaust device that exhausts exhaust gas from a gas turbine includes an exhaust duct and a chimney. This exhaust device may emit sound having a low frequency component of several Hz or less to the outside due to resonance of the sound field inside the gas turbine. For example, low-frequency component sounds often have frequencies below human audible sounds and rarely feel strange noises directly, but they can indirectly cause the window frames of houses around the plant to vibrate. There is.

  As a technique for reducing the sound of such a specific low frequency component, for example, there is a technique described in the following patent document. In the gas turbine exhaust flue described in Patent Document 1, at least a part of the wall of the gas turbine exhaust flue is formed of an acoustic transmission material that sufficiently transmits low-frequency sound of several tens of Hz or less. In addition, the gas turbine exhaust system described in Patent Document 2 is provided with an expansion cylinder having a predetermined space communicating with the inside through an opening around a chimney.

Japanese Patent No. 3310931 JP 2009-287530 A

  Although the conventional technology described above can reduce the sound of low frequency components, it is necessary to enlarge the silencer in order to reduce the resonance vibration of the low frequency sound field below the audible sound, and the manufacturing cost is low. It will increase.

  The present invention solves the above-described problems, and an object of the present invention is to provide an exhaust device that suppresses the sound of low-frequency components and simplifies the structure and reduces the cost.

  The exhaust device of the present invention for achieving the above object includes an exhaust duct for flowing exhaust gas in a horizontal direction, a chimney capable of flowing the exhaust gas flowing in the exhaust duct upward in the vertical direction and releasing it into the atmosphere, A plurality of protrusions provided on the inner surface of the chimney.

  Accordingly, the exhaust gas flows in the exhaust duct in the horizontal direction and moves to the chimney, flows in the chimney upward in the vertical direction, and is discharged to the atmosphere from the opening end at the upper end. At this time, the exhaust gas passing through the chimney collides with a plurality of protrusions provided on the inner surface, and reflection of resonance vibration in the chimney is suppressed. Therefore, the amplification factor amplified by the resonance vibration of the chimney is reduced, and the low frequency component sound radiated from the opening end is suppressed. As a result, it is possible to suppress the generation of low-frequency component sounds, and it is only necessary to provide a plurality of protrusions on the inner surface of the chimney, thereby simplifying the structure and reducing the cost.

  In the exhaust device of the present invention, the plurality of protrusions are provided on the discharge opening end side of the chimney.

  Therefore, on the exhaust opening end side of the chimney, the exhaust gas collides with a plurality of protrusions, and the reflection of resonance vibration is suppressed, effectively suppressing the sound of low frequency components radiated from the opening end. be able to.

  In the exhaust device of the present invention, the plurality of protrusions include a plurality of pin members that protrude from the inner surface of the chimney toward the center.

  Therefore, it is possible to simplify the structure and reduce the cost by configuring the plurality of protrusions with a plurality of pin members.

  In the exhaust device of the present invention, the chimney is provided with an outer wall portion, an inner wall portion, a connecting member that connects the outer wall portion and the inner wall portion, and a heat insulating member interposed between the outer wall portion and the inner wall portion. The plurality of pin members are characterized in that an end portion of the connecting member extends.

  Therefore, the end of the connecting member that connects the outer wall portion and the inner wall portion extends to form the pin member, so that a plurality of protrusions can be easily provided without providing a separate pin member.

  In the exhaust device of the present invention, the plurality of protrusions include a ring member that protrudes toward the center from the inner surface of the chimney.

  Therefore, it is possible to simplify the structure and reduce the cost by configuring the plurality of protrusions with a plurality of ring members.

  In the exhaust device of the present invention, the chimney is configured by connecting a plurality of chimney main bodies having a predetermined length in a ring shape, and the ring member is provided at a connection portion of the chimney main body.

  Therefore, a chimney can be manufactured by connecting a plurality of chimney bodies having a ring shape to form a chimney, for example, by manufacturing a chimney main body at a factory, and transporting and connecting the chimney main body to the site. The workability of the manufacturing work can be improved. And by providing a ring member in the connection part of a chimney main body, a some protrusion part can be easily provided with respect to a chimney, and the workability | operativity of manufacturing operation can be improved also in this point.

  According to the exhaust device of the present invention, since a plurality of protrusions are provided on the inner surface of the chimney, it is possible to suppress the generation of low-frequency component sounds and to simplify the structure and reduce the cost. it can.

FIG. 1 is a schematic diagram illustrating an exhaust device according to Embodiment 1 of the present invention. 2 is a cross-sectional view taken along the line II-II of FIG. 1 showing a cross section of the exhaust duct. FIG. 3 is a cross-sectional view of the upper end portion of the chimney. FIG. 4 is a schematic diagram of a gas turbine having the exhaust device of the first embodiment. FIG. 5 is a perspective view of the exhaust device. FIG. 6 is a schematic diagram illustrating an exhaust device according to Embodiment 2 of the present invention. 7 is a cross-sectional view taken along the line VII-VII in FIG. 6 showing a cross section of the exhaust duct. FIG. 8 is a cross-sectional view of the upper end of the chimney.

  Exemplary embodiments of an exhaust device according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example, Moreover, when there exists multiple Example, what comprises combining each Example is also included.

  1 is a schematic view showing an exhaust device according to Embodiment 1 of the present invention, FIG. 2 is a cross-sectional view taken along the line II-II of FIG. 1 showing a cross section of the exhaust duct, and FIG. FIG. 4 is a schematic view of a gas turbine having the exhaust device of the first embodiment, and FIG. 5 is a perspective view of the exhaust device.

  As shown in FIGS. 4 and 5, the gas turbine according to the first embodiment includes a compressor 11 that compresses air, a combustor 12 that combusts air compressed by the compressor 11, and fuel that is generated by the combustor 12. And a turbine 13 that can be rotated by combustion gas (exhaust gas) generated by combustion of a mixed gas of compressed air, and a generator 14 is connected to a rotating shaft of the compressor 11.

  In the gas turbine, an exhaust duct 15 for guiding exhaust gas discharged from the turbine 13 is connected to the turbine 13, and a chimney 16 is connected to the exhaust duct 15. In this case, the exhaust duct 15 has a rectangular cross-sectional shape, and the chimney 16 has a circular cross-sectional shape. Therefore, the exhaust gas flows in the horizontal direction in the exhaust duct 15, bends substantially at a right angle, is guided to the chimney 16, rises up the chimney 16, and is discharged from the upper opening end 17 to the atmosphere. The gas turbine is not directly connected to the chimney 16 from the exhaust duct 15 but is connected to an exhaust heat recovery boiler (HRSG) (not shown), and the chimney 16 is connected to the exhaust duct of the exhaust heat recovery boiler. .

  Pressure pulsation or exhaust gas turbulence generated in the gas turbine combustor 12 is amplified by resonance vibration when passing through the exhaust duct 15 and the chimney 16, and has a low frequency below the audible sound from the opening of the chimney 16. The sound of the component may be emitted. For example, the sound of the low frequency component is several tens Hz or less (for example, about 1 Hz to 20 Hz). Since this low frequency component is often a frequency component below the human audible sound, humans rarely feel anomalous noise directly, but indirectly the vibration of the window frame of the house around the plant ( It may be a factor that causes backlash.

  The exhaust device according to the first embodiment includes an exhaust duct 15 and a chimney 16, and a plurality of protrusions 21 are provided on an inner surface 16 a of the chimney 16. The plurality of protrusions 21 are provided over a predetermined length region L on the upper opening end (discharge opening end) 17 side of the chimney 16. The plurality of protrusions 21 are constituted by a plurality of pin members that protrude from the inner surface 16 a of the chimney 16 toward the center. The plurality of protrusions 21 are arranged in a staggered manner on the inner surface 16 a of the chimney 16. However, the plurality of projecting portions 21 are not limited to this arrangement, and may be arranged in a lattice shape, for example, or randomly.

  More specifically, as shown in FIG. 3, the chimney 16 includes a cylindrical outer wall part 31, a cylindrical inner wall part 32 positioned inside the outer wall part 31, and the outer wall part 31 and the inner wall part 32. Are formed of a plurality of connecting members (for example, stud bolts) 33 and a heat insulating material 34 interposed between the outer wall portion 31 and the inner wall portion 32.

  The outer wall portion 31 is a cylindrical member having a predetermined inner diameter. The inner wall portion 32 is configured by connecting a plurality of heat retaining panels 35. The heat retaining panel 35 has a predetermined size and a corresponding curved shape of the outer wall portion 31, and is formed in a cylindrical shape by overlapping the left and right end portions, and the upper and lower end portions are overlapped and connected. To form a cylindrical shape of a predetermined length. One end portion of the connecting member 33 is fixed to the inner surface 31a of the outer wall portion 31 by welding, the other end portion passes through an overlapping portion of the plurality of heat retaining panels 35, and a nut 36 is screwed. Therefore, the inner wall 32 having a cylindrical shape is configured by connecting the plurality of heat retaining panels 35 by the connecting member 33, and the inner wall 32 is connected to the inside of the outer wall 31 by the connecting member 33.

  The protrusion 21 described above is constituted by a pin member 37 formed by extending the other end of the connecting member 33. The pin member 37 is integrally formed by extending the other end of the connecting member 33. However, the connecting member 33 and the pin member 37 are formed as separate members, and the pin member 37 is joined to the other end portion of the connecting member 33 by welding or the like, or the pin member 37 is screwed to the other end portion of the connecting member 33. You may do it. In this case, the pin member 37 has the same cylindrical shape as the connecting member 33, but is not limited to this shape, and may be, for example, a prismatic shape or a tapered shape.

  Further, in the exhaust device of the first embodiment, a sound absorbing device 22 is provided on the side of the connection portion between the chimney 16 and the exhaust duct 15.

  In the exhaust system according to the first embodiment configured as described above, the exhaust gas discharged from the gas turbine flows in the exhaust duct 15 in the horizontal direction and moves to the chimney 16, and the chimney 16 flows upward in the vertical direction. It is discharged from the upper opening end 17 to the atmosphere.

  When the exhaust gas flows upward through the chimney 16, the exhaust gas flowing along the inner surface 16a becomes a turbulent flow by colliding with the plurality of projections 21 to generate a turbulent flow and a turbulent boundary layer is generated. The acoustic impedance changes. That is, the low frequency component sound is amplified by the resonance vibration of the chimney 16, but reflection of this resonance vibration is likely to occur at the upper opening end 17. The plurality of protrusions 21 provided on the inner surface 16a in the vicinity of the upper opening end 17 serves as an acoustic resistor, and the acoustic impedance at the upper opening end 17 increases.

  As a result, the exhaust gas is reduced in the amplification factor by which the pressure pulsation generated in the combustor 12 or the turbulent flow of the exhaust gas is amplified by the resonance vibration of the chimney 16, and the sound of the low frequency component radiated from the upper opening end 17 is reduced. Is suppressed.

  In this case, the plurality of protrusions 21 (pin members 37) provided on the inner surface 16 a of the chimney 16 have a sound pressure level (SPL: Sound Pressure Level) [unit: dB] of a low frequency component emitted from the upper opening end 17. ] Is appropriately set according to the inner diameter of the chimney 16, the axial length of the chimney 16, the amount of protrusion from the inner surface 16 a, the distance between each other, and the like. For example, if the protruding amount of the protruding portion 21 (pin member 37) is large, the pressure loss of the exhaust gas at the chimney 16 becomes large. Moreover, when the space | interval of the projection part 21 (pin member 37) is large, a turbulent boundary layer cannot fully be generated and an acoustic impedance hardly changes.

  As described above, in the exhaust device of the first embodiment, the exhaust duct 15 that flows the exhaust gas in the horizontal direction, and the chimney 16 that can flow the exhaust gas flowing in the exhaust duct 15 upward in the vertical direction and release it to the atmosphere. A plurality of protrusions 21 provided on the inner surface 16a of the chimney 16 are provided.

  Therefore, the exhaust gas flows through the exhaust duct 15 in the horizontal direction and moves to the chimney 16, and flows through the chimney 16 upward in the vertical direction and is discharged from the upper opening end 17 to the atmosphere. At this time, the exhaust gas passing through the chimney 16 collides with a plurality of protrusions 21 provided on the inner surface 16a, and reflection of resonance vibrations inside the chimney 16 is suppressed. Therefore, the amplification factor amplified by the resonance vibration of the chimney 16 is reduced, and the low frequency component sound radiated from the upper opening end 17 is suppressed. As a result, the generation of low frequency component sounds can be suppressed. Further, it is only necessary to provide the plurality of protrusions 21 on the inner surface 16a of the chimney 16, and the structure can be simplified and the cost can be reduced.

  In the exhaust device according to the first embodiment, the plurality of protrusions 21 are provided on the upper opening end 17 side of the chimney 16. Therefore, when the exhaust gas is exhausted from the upper opening end 17 of the chimney 16, the exhaust gas collides with the plurality of protrusions 21 and the reflection of resonance vibration is suppressed, and the radiation is effectively emitted from the upper opening end 17. It is possible to suppress the sound of low frequency components.

  In the exhaust duct of the first embodiment, the plurality of protrusions 21 are formed as a plurality of pin members 37 protruding from the inner surface 16 a of the chimney 16 toward the center. Therefore, by forming the protrusion 21 with the pin member 37, the structure can be simplified and the cost can be reduced.

  In the exhaust device of the first embodiment, the outer wall portion 31 and the inner wall portion 32 are connected by the connecting member 33, the heat insulating material 34 is interposed between the outer wall portion 31 and the inner wall portion 32, the chimney 16 is configured, and the connecting member An end portion of 33 is extended to constitute a pin member 37. Therefore, the end portion of the connecting member 33 that connects the outer wall portion 31 and the inner wall portion 32 extends to form the pin member 37, so that the plurality of protruding portions 21 can be easily provided without separately providing a pin member. Can do.

  6 is a schematic view showing an exhaust device according to Embodiment 2 of the present invention, FIG. 7 is a cross-sectional view of FIG. 6 showing a cross section of the exhaust duct, and FIG. 8 is a cross-sectional view of the upper end portion of the chimney. is there. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  As shown in FIGS. 6 and 7, the exhaust device according to the second embodiment includes an exhaust duct 15 and a chimney 16, and a plurality of protrusions 41 are provided on an inner surface 16 a of the chimney 16. The plurality of protrusions 41 are provided on the upper opening end 17 side of the chimney 16. The plurality of protrusions 41 are constituted by ring members that protrude from the inner surface 16a of the chimney 16 toward the center.

  More specifically, as shown in FIG. 8, the chimney 16 includes a cylindrical outer wall portion 31, a cylindrical inner wall portion 32 positioned inside the outer wall portion 31, and the outer wall portion 31 and the inner wall portion 32. Are formed of a plurality of connecting members (for example, stud bolts) 33 and a heat insulating material 34 interposed between the outer wall portion 31 and the inner wall portion 32.

  The chimney 16 is configured by connecting a plurality of chimney main bodies 51, 52... Having a predetermined length in a ring shape, and the ring member 42 constituting the protruding portion 41 is formed by the chimney main bodies 51, 52. Are provided at each connecting portion.

  That is, the chimney main body 51 is configured by connecting the inner wall portion 32 formed by connecting a plurality of heat retaining panels 35 to the cylindrical outer wall portion 31 having a predetermined length by the connecting member 33. And the ring member 42 is connected to the lower part of the chimney main body 51 by welding. The ring member 42 has a circular opening 42 a formed at the center of the disk, and the outer peripheral portion is fixed to the lower end of the outer wall portion 31 by welding. In this case, you may fix the lower end of the ring member 42 and the inner wall part 32 by welding. Further, the chimney main body 52 is configured in substantially the same manner. And the chimney main body 51 and the chimney main body 52, ie, the ring member 42 of the chimney main body 51, and the upper end part of the outer wall part 31 of the chimney main body 52 are being fixed by welding.

  In this case, the chimney main bodies 51, 52... Are manufactured alone at the factory, the manufactured chimney main bodies 51, 52. The chimney 16 is constructed by connecting 51, 52.

  In the exhaust system according to the second embodiment configured as described above, the exhaust gas discharged from the gas turbine flows in the exhaust duct 15 in the horizontal direction and moves to the chimney 16, and the chimney 16 flows upward in the vertical direction. It is discharged from the upper opening end 17 to the atmosphere.

  When the exhaust gas flows upward through the chimney 16, the exhaust gas flowing along the inner surface 16a becomes a turbulent flow by colliding with the plurality of protrusions 41 to generate a turbulent flow and a turbulent boundary layer is generated. The acoustic impedance changes. That is, the low frequency component sound is amplified by the resonance vibration of the chimney 16, but reflection of this resonance vibration is likely to occur at the upper opening end 17. The plurality of protrusions 41 provided on the inner surface 16a in the vicinity of the upper opening end 17 serves as an acoustic resistor, and the acoustic impedance at the upper opening end 17 increases.

  As a result, the exhaust gas is reduced in the amplification factor by which the pressure pulsation generated in the combustor 12 or the turbulent flow of the exhaust gas is amplified by the resonance vibration of the chimney 16, and the sound of the low frequency component radiated from the upper opening end 17 is reduced. Is suppressed.

  In this case, the plurality of protrusions 41 (ring members 42) provided on the inner surface 16a of the chimney 16 has a chimney 16 so that the sound pressure level of the low frequency component emitted from the upper opening end 17 is equal to or lower than the target value. Are appropriately provided according to the inner diameter, the axial length, the thickness, the amount of protrusion from the inner surface 16a (the diameter of the opening 42a), the distance between them.

  As described above, in the exhaust system of the second embodiment, the exhaust duct 15 that flows the exhaust gas in the horizontal direction, and the chimney 16 that can flow the exhaust gas flowing in the exhaust duct 15 upward in the vertical direction and release it to the atmosphere. A plurality of protrusions 41 provided on the inner surface 16a of the chimney 16 are provided.

  Therefore, the exhaust gas passing through the chimney 16 collides with the plurality of projections 41 provided on the inner surface 16a, and reflection of resonance vibrations inside the chimney 16 is suppressed. Therefore, the amplification factor amplified by the resonance vibration of the chimney 16 is reduced, and the low frequency component sound radiated from the upper opening end 17 is suppressed. As a result, the generation of low frequency component sounds can be suppressed. Further, it is only necessary to provide the plurality of protrusions 41 on the inner surface 16a of the chimney 16, and the structure can be simplified and the cost can be reduced.

  In the exhaust device of the second embodiment, the plurality of protrusions 41 are ring members 42 that protrude from the inner surface 16a of the chimney 16 toward the center. Therefore, the structure can be simplified and the cost can be reduced.

  Specifically, the chimney 16 is configured by connecting a plurality of chimney main bodies 51, 52... Having a predetermined length in a ring shape, and a ring member 42 is provided at a connection portion of each chimney main body 51, 52. Yes. For example, the chimney 16 can be easily manufactured by manufacturing the chimney main bodies 51, 52... At the factory, and transporting and connecting the chimney main bodies 51, 52. Can be improved. And by providing the ring member 42 in the connection part of chimney main bodies 51, 52 ..., the several projection part 41 can be easily provided with respect to the chimney 16, The workability | operativity of manufacturing work is also this point. Can be improved.

  In the above-described embodiment, the protrusions 21 and 41 are the pin member 37 and the ring member 42, but the present invention is not limited to this configuration. For example, a spiral member may be fixed to the inner surface 16a of the chimney 16, a convex portion may be randomly formed, or a protrusion may be integrally formed on the inner wall portion 32 as the chimney 16 itself.

  In the above-described embodiments, the exhaust device of the present invention has been described as applied to an exhaust system of a gas turbine. However, the present invention can also be applied to another exhaust system such as a steam turbine.

DESCRIPTION OF SYMBOLS 11 Compressor 12 Combustor 13 Turbine 14 Generator 15 Exhaust duct 16 Chimney 16a Inner surface 17 Upper opening end (discharge opening end)
DESCRIPTION OF SYMBOLS 21 Protrusion part 31 Outer wall part 32 Inner wall part 33 Connection member 34 Heat insulating material 37 Pin member 41 Projection part 42 Ring member 51,52 Chimney main body

Claims (5)

An exhaust duct for flowing exhaust gas horizontally;
A chimney capable of flowing the exhaust gas flowing through the exhaust duct upward in the vertical direction and releasing it into the atmosphere;
A plurality of protrusions provided on the inner surface of the chimney;
I have a,
The protrusion has a plurality of pin members protruding from the inner surface of the chimney toward the center, and the plurality of pin members are arranged in a staggered manner.
An exhaust system characterized by that. The chimney has an outer wall portion, an inner wall portion, a connecting member that connects the outer wall portion and the inner wall portion, and a heat insulating material interposed between the outer wall portion and the inner wall portion, The exhaust device according to claim 1 , wherein the plurality of pin members are configured by extending end portions of the connecting members. An exhaust duct for flowing exhaust gas horizontally;
A chimney capable of flowing the exhaust gas flowing through the exhaust duct upward in the vertical direction and releasing it into the atmosphere;
A plurality of protrusions provided on the inner surface of the chimney;
I have a,
The protrusion has a ring member protruding from the inner surface of the chimney toward the center.
An exhaust system characterized by that. The exhaust device according to claim 3 , wherein the chimney is configured by connecting a plurality of chimney main bodies having a predetermined length in a ring shape, and the ring member is provided at a connection portion of the chimney main body. The chimney is a cylindrical member having a predetermined inner diameter and an inner diameter of the same diameter in the longitudinal direction, the plurality of protrusions claim 1, characterized in that provided in the discharge opening end side of the chimney The exhaust device according to any one of claims 1 to 4 .

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