Patent Application
20130000306
The present invention relates to a gas-turbine combustion burner applied to a gas-turbine combustor.
In a combustion region formed inside a combustion cylinder of a gas-turbine combustor, pressure fluctuations are generated by flames, those pressure fluctuations propagate (feed back) to a gas-turbine combustion burner, the flow rate of fuel sprayed (ejected) into the combustion region from fuel spraying holes in the gas-turbine combustion burner fluctuates, and that flow-rate fluctuation propagates to the flames, aggravating the pressure fluctuations.
Therefore, one known way to suppress the pressure fluctuations in the combustion region is to use an acoustic liner disclosed, for example, in Patent Literature 1.
However, the acoustic liner disclosed in Patent Literature is based on the technical idea of suppressing pressure fluctuations in the combustion region and suppressing pressure fluctuations that propagate to the gas-turbine combustion burner, to suppress flow-rate fluctuations in the fuel sprayed into the combustion region from fuel spraying holes in the gas-turbine combustion burner, and is not based on the technical idea of increasing the impedance (resistance) in the fuel supply system to reduce the propagation of pressure fluctuations from the combustion region to the fuel supply system. In addition, if the pressure fluctuations in the combustion region remarkably increase for some reason, it is not possible to sufficiently suppress the pressure fluctuations in the combustion region with, for example, just the acoustic liner disclosed in Patent Literature 1, and the pressure fluctuations in the combustion region become a problem.
The present invention has been conceived in light of the circumstances described above, and an object thereof is to provide a gas-turbine combustion burner that can reduce, as much as possible, the propagation of pressure fluctuations from the combustion region to the fuel supply system by increasing the impedance of the fuel supply system, thereby making it possible to reduce fluctuations in the flow rate of fuel sprayed into the combustion region from fuel spraying holes in the gas-turbine combustion burner.
In order to solve the problem described above, the present invention employs the following solutions.
A gas-turbine combustion burner according to the present invention is provided, at a distal end thereof, with a fuel spraying hole that sprays fuel into a combustion region formed inside a combustion cylinder of a gas-turbine combustor and in which a fuel flow path that guides the fuel, which is supplied from a fuel source, to the fuel spraying hole is formed in the interior thereof, wherein the impedance of a fuel supply system, which guides the fuel from the fuel source to the fuel spraying hole, is set so that propagation of pressure fluctuations from the combustion region to the fuel supply system becomes an allowable level or less.
A gas-turbine combustion burner according to the present invention is provided, at a distal end thereof, with a fuel spraying hole that sprays fuel into a combustion region formed inside a combustion cylinder of a gas-turbine combustor and in which a fuel flow path that guides the fuel, which is supplied from a fuel source, to the fuel spraying hole is formed in the interior thereof, wherein a hole diameter of the fuel spraying hole is set so that propagation of pressure fluctuations from the combustion region to a fuel supply system becomes an allowable level or less.
With the gas-turbine combustion burner according to the present invention, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region to the fuel supply system by increasing the impedance of the fuel spraying hole (in other words, the impedance of the fuel supply system that guides the fuel from a fuel source to the fuel spraying hole), thereby making it possible to reduce fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
In the above-described gas-turbine combustion burner, preferably, the fuel spraying hole includes a reduced-diameter portion that extends from an inlet thereof to a point at ¼ of a flow path length thereof, a first straight portion that extends from the point at ¼ of the flow path length thereof to a point at 2/4 of the flow path length thereof, a wide-diameter portion that extends from the point at 2/4 of the flow path length thereof to a point at ¾ of the flow path length thereof, and a second straight portion that extends from the point at ¾ of the flow path length thereof to an outlet thereof.
With such a gas-turbine combustion burner, pressure losses occur at a first stepped portion (first edge portion) formed at the connecting portion between the first straight portion and the wide-diameter portion, and also at a second stepped portion (second edge portion) formed at the connecting portion between the wide-diameter portion and the second straight portion; therefore, the impedance of the fuel spraying hole becomes even larger, and thus the propagation of pressure fluctuations from the combustion region to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
In addition, a pressure loss occurs at a constricted portion formed at the connecting portion between the reduced-diameter portion and the first straight portion (in other words, where the outlet of the reduced-diameter portion meets the inlet of the first straight portion); therefore, the impedance of the fuel spraying hole becomes even larger, and thus the propagation of pressure fluctuations from the combustion region to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
In the above-described gas-turbine combustion burner, more preferably, an inner diameter of the wide-diameter portion is set to be 1.5 to 5 times an inner diameter of the first straight portion.
With such a gas-turbine combustion burner, it is possible to effectively reduce the noise of flowing fuel in the wide-diameter portion, whose inner diameter is set to be 1.5 to 5 times the inner diameter of the first straight portion.
In the above-described gas-turbine combustion burner, more preferably, the fuel spraying hole includes a reduced-diameter portion that extends from an inlet thereof to a point at ⅓ of a flow path length thereof, a straight portion that extends from the point at ⅓ of the flow path length thereof to a point at ⅔ of the flow path length thereof, and a wide-diameter portion that extends from the point at ⅔ of the flow path length thereof to an outlet thereof.
With such a gas-turbine combustion burner, a pressure loss occurs at a stepped portion (edge portion) formed at the connecting portion between the straight portion and the wide-diameter portion; therefore, the impedance of the fuel spraying hole becomes even larger, and thus the propagation of pressure fluctuations from the combustion region to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
Moreover, a pressure loss occurs at a constricted portion formed at the connecting portion between the reduced-diameter portion and the straight portion (in other words, where the outlet of the reduced-diameter portion meets the inlet of the straight portion); therefore, the impedance of the fuel spraying hole becomes even larger, and thus the propagation of pressure fluctuations from the combustion region to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
In the above-described gas-turbine combustion burner, more preferably, an inner diameter of the wide-diameter portion is set to be 1.5 to 5 times an inner diameter of the straight portion.
With such a gas-turbine combustion burner, it is possible to effectively reduce the noise of flowing fuel in the wide-diameter portion, whose inner diameter is set to be 1.5 to 5 times the inner diameter of the straight portion.
In the above-described gas-turbine combustion burner, more preferably, the fuel spraying hole includes a reduced-diameter portion that gradually reduces in diameter from an inlet thereof to an intermediate point in a flow path length thereof, and a wide-diameter portion that gradually increases in diameter from the intermediate point in the flow path length thereof to an outlet thereof.
With such a gas-turbine combustion burner, a pressure loss occurs at a constricted portion formed at the connecting portion between the reduced-diameter portion and the wide-diameter portion (in other words, where the outlet of the reduced-diameter portion meets the inlet of the wide-diameter portion); therefore, the impedance of the fuel spraying hole becomes even larger, and thus the propagation of pressure fluctuations from the combustion region to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
A gas-turbine combustion burner according to the present invention is provided, at a distal end thereof, with a fuel spraying hole that sprays fuel into a combustion region formed inside a combustion cylinder of a gas-turbine combustor and in which a fuel flow path that guides the fuel, which is supplied from a fuel source, to the fuel spraying hole is formed in the interior thereof, wherein the flow-path cross-sectional area of the fuel flow path is set so that propagation of pressure fluctuations from the combustion region to a fuel supply system becomes an allowable level or less.
With the gas-turbine combustion burner according to the present invention, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region to the fuel supply system by increasing the impedance of the fuel flow path (in other words, the impedance of the fuel supply system that guides the fuel from a fuel source to the fuel spraying hole), thereby making it possible to reduce fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
In the above-described gas-turbine combustion burner, more preferably, a sound-absorbing material is provided at the radially outer side of the fuel flow path.
With such a gas-turbine combustion burner, pulsations in the fuel passing through the fuel flow path are absorbed by the sound-absorbing material, and therefore, (substantially) constant fuel can always be sprayed from the fuel spraying hole, making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
A gas-turbine combustion burner according to the present invention is provided, at a distal end thereof, with a fuel spraying hole that sprays fuel into a combustion region formed inside a combustion cylinder of a gas-turbine combustor and in which a fuel flow path that guides the fuel, which is supplied from a fuel source, to the fuel spraying hole is formed in the interior thereof, wherein a baffle plate or orifice provided with a slit is provided in the fuel flow path so that propagation of pressure fluctuations from the combustion region to a fuel supply system becomes an allowable level or less.
With the gas-turbine combustion burner according to the present invention, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region to the fuel supply system by increasing the impedance of the fuel flow path (in other words, the impedance of the fuel supply system that guides the fuel from a fuel source to the fuel spraying hole), thereby making it possible to reduce fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
In the above-described gas-turbine combustion burner, more preferably, the baffle plate or orifice is made of a sound-absorbing material.
With such a gas-turbine combustion burner, pulsations in the fuel passing through the fuel flow path are absorbed by the baffle plate made of the sound-absorbing material (or the orifice made of the sound-absorbing material), and therefore, (substantially) constant fuel can always be sprayed from the fuel spraying hole, which makes it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the fuel spraying hole into the combustion region.
A gas-turbine combustor according to the present invention includes one of the gas-turbine combustion burners described above.
With the gas-turbine combustor according to the present invention, (substantially) constant fuel is always sprayed form the fuel spraying hole, and therefore, it is possible to suppress (reduce) aggravation of the pressure fluctuations caused by fluctuations in the flow rate of the fuel sprayed into the combustion region from the fuel spraying hole in the gas-turbine combustion burner and those flow-rate fluctuations propagating to the flames.
With the gas-turbine combustion burner according to the present invention, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from a combustion region to a fuel supply system by increasing the impedance of the fuel supply system, thereby making it possible to reduce fluctuations in the flow rate of fuel that is sprayed into the combustion region from fuel spraying holes in the gas-turbine combustion burner.
A gas-turbine combustion burner according to a first embodiment of the present invention will be described below with reference to
As shown in
The main combustion burners 5 are provided at equal intervals (45° intervals) in the circumferential direction, and the pilot combustion burner 6 is provided so as to be located at (substantially) the center of the main combustion burners 5.
As shown in
Reference signs 9 in
The hole diameter of the spraying holes 6a according to this embodiment is determined using the graphs shown in
The normal-incidence sound absorption coefficient indicates how much a pressure wave propagated from the combustion region 3 to the spraying holes 6a is absorbed in the spraying holes 6a; when the value thereof is “1”, the pressure wave propagated from the combustion region 3 to the spraying holes 6a is completely absorbed in the spraying holes 6a, and when the value thereof is “0”, the pressure wave propagated from the combustion region 3 to the spraying holes 6a is completely reflected at the spraying holes 6a. Also, regarding the acoustic resistance Re, a value greater than “1” cannot exist; it must be “1” or less.
With the pilot combustion burner 6 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the spraying holes 6a (in other words, the impedance of the fuel supply system that guides the fuel from a fuel source to the spraying holes 6a), thereby making it possible to reduce fluctuations in the flow rate of the fuel sprayed from the spraying holes 6a into the combustion region 3.
A second embodiment of the gas-turbine combustion burner according to the present invention will be described with reference to
A pilot combustion burner (gas-turbine combustion burner) 21 according to this embodiment differs from that of the first embodiment described above in that, instead of reducing the hole diameter of the spraying holes 6a to increase the impedance of the spraying holes 6a (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 6a), the flow-path cross-sectional area of a fuel passage 22 provided in the interior thereof is made smaller than the flow-path cross-sectional area of the fuel passage 8 (see
Parts that are identical to those in the first embodiment described above are assigned the same reference signs. Also, reference signs 10 in
The flow-path cross-sectional area of the fuel passage 22 is determined using the same procedure as the procedure described in the first embodiment. Namely, an acoustic resistance Re=0.5 at which the normal-incidence sound absorption coefficient α is approximately 0.9 is selected, and then, the fuel-path cross-sectional area is determined so that the acoustic resistance Re for the rated flow velocity (average flow velocity) of the fuel flowing through the fuel passage (fuel pipe) provided inside the pilot combustion burner 21 is larger than 0.5.
With the pilot combustion burner 21 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the fuel flow path 22 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 10), thereby making it possible to reduce fluctuations in the flow rate of the fuel sprayed from the spraying holes 10 into the combustion region 3.
A third embodiment of the gas-turbine combustion burner according to the present invention will be described with reference to
A pilot combustion burner (gas-turbine combustion burner) 31 according to this embodiment differs from that in the first embodiment described above in that, instead of reducing the hole diameter of the spraying holes 6a to increase the impedance of the spraying holes 6a (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 6a), a baffle plate 33 (or orifice) provided with a slit 32 is disposed at an intermediate point in the fuel passage 8 provided in the interior thereof (more specifically, inside the fuel passage 8 at a location near the upstream side of the spraying holes 6a) to increase the impedance of the fuel flow path 22 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 10). The other constituent elements are the same as those in the first embodiment described above, and therefore, a description of those constituent elements is omitted here.
Parts that are identical to those in the first embodiment described above are assigned the same reference signs. In addition, reference signs 10 in
The size of the slit 32 (or a hole provided in an orifice) is determined using the same procedure as the procedure described in the first embodiment. Namely, an acoustic resistance Re=0.5 at which the normal-incidence sound absorption coefficient α is approximately 0.9 is selected, and then, the slit size is determined so that the acoustic resistance Re for the rated flow velocity (average flow velocity) of the fuel flowing through the fuel passage (fuel pipe) provided in the interior of the pilot combustion burner 31 is larger than 0.5.
With the pilot combustion burner 31 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the fuel flow path 8 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 10), thereby making it possible to reduce fluctuations in the flow rate of the fuel sprayed from the spraying holes 10 into the combustion region 3.
A fourth embodiment of the gas-turbine combustion burner according to the present invention will be described with reference to
A pilot combustion burner (gas-turbine combustion burner) 41 according to this embodiment differs from that of the first embodiment described above in that, instead of reducing the hole diameter of the spraying holes 6a to increase the impedance of the spraying holes 6a (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 6a), the flow-path cross-sectional area of a fuel passage 42 provided in the interior thereof is made smaller than the flow-path cross-sectional area of the fuel passage 8 (see
Parts that are identical to those in the first embodiment described above are assigned the same reference signs. In addition, reference signs 10 in
The flow-path cross-sectional area of the fuel passage 42 is determined using the same procedure as the procedure described in the first embodiment. Namely, an acoustic resistance Re=0.5 at which the normal-incidence sound absorption coefficient a is approximately 0.9 is selected, and then the flow-path cross-sectional area is determined so that the acoustic resistance Re for the rated flow velocity (average flow velocity) of the fuel that flows through the fuel passage (fuel pipe) provided inside the pilot combustion burner 41 is greater than 0.5.
With the pilot combustion burner 41 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the fuel flow path 42 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 10), thereby making it possible to reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 10 into the combustion region 3.
In addition, pulsations in the fuel passing through the fuel flow path 42 are absorbed by the sound-absorbing material 43, and therefore, (substantially) constant fuel can always be sprayed from the spraying holes 10, making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 10 into the combustion region 3.
A fifth embodiment of the gas-turbine combustion burner according to the present invention will be described with reference to
A pilot combustion burner (gas-turbine combustion burner) 51 according to this embodiment differs from that in the first embodiment described above in that, instead of reducing the hole diameter of the spraying holes 6a to increase the impedance of the spraying holes 6a (in other words, the impedance of the fuel supply system that guides the fuel from the fuel source to the spraying holes 6a), a slit 52 is provided at an intermediate position in the fuel passage 8 provided in the interior thereof (more specifically, in the fuel passage 8 at a location close to the upstream side of the spraying holes 6a), and a baffle plate 53 made of a sound-absorbing material such as rock wool (or an orifice made of a sound-absorbing material such as rock wool) is disposed thereat to increase the impedance of the fuel flow path 8 (in other words, the impedance of the fuel-supply system that guides fuel from the fuel source to the spraying holes 10). The other constituent elements are the same as those in the first embodiment described above, and a description of those constituent elements is omitted here.
Parts identical to those in the first embodiment described above are assigned the same reference signs. In addition, reference signs 10 in
The size of the slit 52 (or the hole provided in the orifice) is determined using the same procedure as the procedure described in the first embodiment. Namely, an acoustic resistance Re=0.5 at which the normal-incidence sound absorption coefficient α is approximately 0.9 is selected, and then the slit size is determined so that the acoustic resistance Re for the rated flow velocity (average flow velocity) of the fuel that flows through the fuel passage (fuel pipe) provided in the interior of the pilot combustion burner 51 is greater than 0.5.
With the pilot combustion burner 51 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the fuel flow path 8 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 10), thereby making it possible to reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 10 into the combustion region 3.
In addition, pulsations in the fuel passing through the fuel flow path 8 are absorbed by the baffle plate 53 made of the sound-absorbing material (or the orifice made of the sound-absorbing material), and therefore, (substantially) constant fuel can always be sprayed from the spraying holes 10, which makes it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 10 into the combustion region 3.
A sixth embodiment of the gas-turbine combustion burner according to the present invention will be described with reference to
A pilot combustion burner (gas-turbine combustion burner) 61 according to this embodiment differs from those in the first to fifth embodiments described above in that spraying holes 62 are provided instead of the spraying holes 6a. The other constituent elements are the same as those in the first to fifth embodiments described above, and a description of those constituent elements will be omitted here.
As shown in
With the pilot combustion burner 61 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the spraying holes 62 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 62), thereby making it possible to reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 62 into the combustion region 3.
In addition, a pressure loss occurs at a constricted portion formed at the connecting portion between the reduced-diameter portion 62a and the wide-diameter portion 62b (in other words, where the outlet of the reduced-diameter portion 62a meets the inlet of the wide-diameter portion 62b); therefore, the impedance of the spraying holes 62 becomes even larger, and thus the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 62 into the combustion region 3.
A seventh embodiment of the gas-turbine combustion burner according to the present invention will be described with reference to
A pilot combustion burner (gas-turbine combustion burner) 71 according to this embodiment differs from those in the first to fifth embodiments in that spraying holes 72 are provided instead of the spraying holes 6a. The other constituent elements are the same as those in the first to fifth embodiments described above, and therefore, a description of those constituent elements will be omitted here.
As shown in
In this embodiment, the inner diameter (hole diameter) of the wide-diameter portion 72c is set to be about 1.5 to 5 times the inner diameter (hole diameter) of the straight portion 72b.
With the pilot combustion burner 71 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the spraying holes 72 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 72), thereby making it possible to reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 72 into the combustion region 3.
In addition, a pressure loss occurs at a stepped portion (edge portion) formed at the connecting portion between the straight portion 72b and the wide-diameter portion 72c; therefore, the impedance of the spraying holes 72 becomes even larger, and thus the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 72 into the combustion region 3.
A pressure loss occurs at a constricted portion formed at the connecting portion between the reduced-diameter portion 72a and the straight portion 72b (in other words, where the outlet of the reduced-diameter portion 72a meets the inlet of the straight portion 72b); therefore, the impedance of the spraying holes 72 becomes even larger, and thus the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 72 into the combustion region 3.
Furthermore, with the pilot combustion burner 71 according to this embodiment, it is possible to effectively reduce the acoustic of flowing fuel in the wide-diameter portion 72c, whose inner diameter is set to be 1.5 to 5 times the inner diameter of the straight portion 72b.
An eighth embodiment of the gas-turbine combustion burner according to the present invention will be described with reference to
A pilot combustion burner (gas-turbine combustion burner) 81 according to this embodiment differs from those in the first to fifth embodiments described above in that spraying holes 82 are provided instead of the spraying holes 6a. The other constituent elements are the same as those in the first to fifth embodiments described above, and therefore, a description of those constituent elements will be omitted here.
As shown in
In this embodiment, the inner diameter (hole diameter) of the wide-diameter portion 82c is set to be 1.5 to 5 times the inner diameter (hole diameter) of the first straight portion 82b.
With the pilot combustion burner 81 according to this embodiment, it is possible to reduce, as much as possible, the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system by increasing the impedance of the spraying holes 82 (in other words, the impedance of the fuel supply system that guides fuel from the fuel source to the spraying holes 82), thereby making it possible to reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 82 into the combustion region 3.
In addition, pressure losses occur at a first stepped portion (first edge portion) formed at the connecting portion between the first straight portion 82b and the wide-diameter portion 82c, and also at a second stepped portion (second edge portion) formed at the connecting portion between the wide-diameter portion 82c and the second straight portion 82d; therefore, the impedance of the spraying holes 82 becomes even larger, and thus the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 82 into the combustion region 3.
A pressure loss occurs at a constricted portion formed at the connecting portion between the reduced-diameter portion 82a and the first straight portion 82b (in other words, where the outlet of the reduced-diameter portion 82a meets the inlet of the first straight portion 82b); therefore, the impedance of the spraying holes 82 becomes even larger, and thus the propagation of pressure fluctuations from the combustion region 3 to the fuel supply system can be reduced even more, thereby making it possible to further reduce the fluctuations in the flow rate of the fuel sprayed from the spraying holes 82 into the combustion region 3.
Furthermore, with the pilot combustion burner 81 according to this embodiment, it is possible to effectively reduce the acoustic of flowing fuel in the wide-diameter portion 82c, whose inner diameter is set to be 1.5 to 5 times the inner diameter of the first straight portion 82b.
The present invention is not restricted to the embodiments described above; for example, it can be realized by combining the embodiments described above as appropriate, or by making changes or modifications.
Furthermore, the present invention need not be applied only to the pilot combustion burner 6; it can also be applied to the main combustion burners 5.
In addition, the flow path lengths of the reduced-diameter portion 62a and the wide-diameter portion 62b described in the sixth embodiment; the reduced-diameter portion 72a, the straight portion 72b, and the wide-diameter portion 72c described in the seventh embodiment; and the reduced-diameter portion 82a, the first straight portion 82b, the wide-diameter portion 82c, and the second straight portion 82d described in the eighth embodiment are not restricted to the embodiments described above; modifications are permissible as appropriate.
1 gas-turbine combustor
2 combustion cylinder
3 combustion region
6 pilot combustion burner (gas-turbine combustion burner)
6
a fuel spraying hole
8 fuel flow path
10 fuel spraying hole
21 gas-turbine combustion burner
22 fuel flow path
31 gas-turbine combustion burner
32 slit
33 baffle plate
41 gas-turbine combustion burner
42 fuel flow path
43 sound-absorbing material
51 gas-turbine combustion burner
52 slit
53 baffle plate
61 gas-turbine combustion burner
62 fuel spraying hole
62
a reduced-diameter portion
62
b wide-diameter portion
71 gas-turbine combustion burner
72 fuel spraying hole
72
a reduced-diameter portion
72
b straight portion
72
c wide-diameter portion
81 gas-turbine combustion burner
82 fuel spraying hole
82
a reduced-diameter portion
82
b first straight portion
82
c wide-diameter portion
82
d second straight portion
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-274516 | Dec 2009 | JP | national |
