JP6182395B2 - Gas turbine combustor and control method thereof - Google Patents

Description

  The present invention relates to a gas turbine combustor and a control method thereof.

  For the purpose of providing a gas turbine combustor with low Nox and excellent combustion stability, the fuel nozzle includes a fuel nozzle that ejects fuel into the combustion chamber, and an air hole that ejects air into the combustion chamber. There is a gas turbine combustor in which the fuel nozzle and the air hole are arranged so that the air is jetted into the combustion chamber as a plurality of coaxial jets (see, for example, Patent Document 1).

JP 2003-148734 A

  Gas turbines are required to operate stably through a wide range of operating conditions from ignition to transition to rated load. For this reason, a multi-burner system provided with a plurality of burners is widely used for the combustor. In a multi-burner type combustor, for example, when the amount of fuel supplied, such as ignition, is small, fuel is injected from only one burner disposed in the center (hereinafter referred to as F1 burner), and F1 is increased according to the increase in the amount of fuel supplied. The number of fuel injections of a plurality of burners (hereinafter referred to as F2 burners) arranged on the outer periphery of the burner is sequentially increased. And it operates so that fuel may be injected from all the burners at the time of rated load operation.

  The burner of the gas turbine combustor described in Patent Document 1 described above has an inner peripheral air hole disposed in the center region thereof, an outer peripheral air hole disposed on the outer peripheral side thereof, and a jet ejected from the inner peripheral air hole. The distance between the flame formed by the air-fuel mixture and the outer peripheral air hole outlet is ensured. By securing such a distance, fuel and air are further mixed before the premixed gas jetted from the outer peripheral air hole reacts with the flame and burns. This achieves low NOx combustion. Thus, from the viewpoint of low NOx combustion, it is advantageous that the flame formed by the burner is a conical flame that holds the flame starting from the inner peripheral air hole outlet.

However, when the air temperature is low, such as when the gas turbine is started up / accelerated, and fuel is supplied only to the F1 burner of the multi-burner, if a conical flame is formed by the F1 burner, the outer peripheral air hole in the F1 burner The premixed gas ejected from the air may interfere with low-temperature air ejected from the F2 burner arranged around the F1 burner before reacting with the flame.
At this time, the stronger the degree of interference, the lower the fuel-air ratio of the premixed gas jetted from the outer peripheral air hole of the F1 burner, the combustion reaction does not proceed, and the amount of unburned emissions increases. In addition, when the F1 burner is premixed and burned uniformly on the inner and outer peripheries and a flat flame is formed, there is a concern that combustion vibration may occur.

  The present invention has been made on the basis of the above-mentioned matters, and its purpose is to suppress the discharge of unburned components and combustion vibrations at the time of start-up / acceleration of the gas turbine, and to stabilize the rotational speed of the gas turbine. It is an object of the present invention to provide a gas turbine combustor that can be increased and a control method thereof.

In order to solve the above problems, for example, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above-described problems. To give an example, a cylindrical combustion chamber that mixes the supplied fuel and the supplied air and burns, and the combustion chamber The fuel is supplied to an air hole plate formed on the upstream side and formed with a plurality of air holes for supplying air to the combustion chamber, and a plurality of air holes arranged on the upstream side of the air hole plate and formed in the air hole plate. A plurality of fuel nozzles to be supplied; a plurality of burners configured such that the plurality of fuel nozzles and the plurality of air holes are respectively paired; and the combustion chamber of the plurality of burners facing the combustion chamber. In the gas turbine combustor comprising a starting F1 burner disposed at the axial center of the air hole plate and a plurality of F2 burners disposed on the outer periphery of the F1 burner, the fuel nozzle of the F1 burner; The air holes are arranged on the circumference of a plurality of rows, and the air holes of the F1 burner are an inner peripheral air hole arranged radially inside and an outer circumference arranged on the outer peripheral side of the inner peripheral air hole. The F1 burner includes an inner peripheral fuel nozzle disposed corresponding to the inner peripheral air hole, an outer peripheral fuel nozzle disposed corresponding to the outer peripheral air hole, A fuel header for supplying fuel to the inner peripheral fuel nozzle and the outer peripheral fuel nozzle; an inner peripheral orifice communicating the fuel header and the inner peripheral fuel nozzle; the fuel header and the outer peripheral fuel nozzle; An outer peripheral orifice communicating with the outer peripheral orifice, wherein the inner peripheral orifice has a smaller diameter than the outer peripheral orifice, and the fuel / air ratio at the outlet of the inner peripheral air hole is a fuel / air ratio at the outlet of the outer peripheral air hole. It is smaller than the ratio To.

  According to the present invention, it is possible to suppress the discharge of unburned fuel and combustion vibration during startup / acceleration of the gas turbine, so that the operating range of the startup F1 burner can be expanded. As a result, it is possible to provide a gas turbine combustor that can stably increase the rotational speed of the gas turbine and a control method therefor.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic block diagram which represented the side sectional drawing of the principal part of 1st Embodiment of the gas turbine combustor and its control method of this invention with the schematic diagram of the whole gas turbine plant. It is the schematic block diagram which represented the sectional side view of the principal part of 1st Embodiment of the gas turbine combustor and its control method of this invention with the situation figure which shows the flow of the combustion gas in a combustion chamber. It is the front view which looked at an example of the air hole plate which comprises 1st Embodiment of the gas turbine combustor and its control method of this invention from the combustion chamber side. Schematic configuration diagram showing a detailed side sectional view of an example of the F1 burner constituting the first embodiment of the gas turbine combustor and its control method of the present invention together with a situation diagram showing the flow of combustion gas in the combustion chamber It is. It is a characteristic view which shows the flame form at the time of starting / acceleration of F1 burner which comprises 1st Embodiment of the gas turbine combustor of this invention, and its control method. FIG. 2 is another example of FIG. 2, in the F1 burner, an outline that is shown together with a situation diagram showing a flame form when the fuel cost of the outer peripheral portion is lower than the fuel cost that can hold the flame at the air hole outlet. It is a block diagram. It is a detailed sectional side view which shows the other example of F1 burner which comprises 1st Embodiment of the gas turbine combustor of this invention, and its control method. It is the front view which looked at the other example of F1 burner shown in FIG. 7 from the combustion chamber side. It is the schematic block diagram which represented the sectional side view of the principal part of 2nd Embodiment of the gas turbine combustor and its control method of this invention with the situation figure which shows the flow of the combustion gas in a combustion chamber. It is the front view which looked at an example of the air hole plate which comprises 2nd Embodiment of the gas turbine combustor of this invention, and its control method from the combustion chamber side. It is a characteristic view which shows the flame form at the time of all the burner flame formation of F1 burner which comprises 2nd Embodiment of the gas turbine combustor of this invention, and its control method.

  Embodiments of a gas turbine combustor and a control method thereof according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a side sectional view of a main part of a first embodiment of a gas turbine combustor and a control method thereof according to the present invention together with a schematic diagram of an entire gas turbine plant.
The gas turbine plant 9 shown in FIG. 1 mainly combusts the compressor 1 that pressurizes the intake air 15 to generate the high-pressure air 16, and the high-pressure air 16 generated by the compressor 1 and the gas fuel 50 to perform high-temperature combustion. A combustor 2 that generates a gas 19, a turbine 3 that is driven by the high-temperature combustion gas 19 generated by the combustor 2, a generator 8 that is rotated by driving the turbine 3 to generate electric power, a compressor 1, and a turbine 3 And a shaft 7 for connecting the generator 8 together.

The combustor 2 is stored inside the casing 4.
The combustor 2 includes a multi-burner 6 disposed at the head, a generally cylindrical combustor liner 10 that forms a combustion chamber 5 in which high-pressure air 16 and gas fuel 50 are combusted, and an outer periphery of the combustor liner 10. Are arranged in a substantially concentric cylindrical shape, and are arranged on the downstream side of the combustor liner 10 and are generated in the combustion chamber 5, and are arranged on the downstream side of the combustor liner 10. A tail cylinder inner cylinder 12 for guiding the high-temperature combustion gas 19 to the turbine 3 and a tail cylinder outer cylinder 13 disposed on the outer peripheral side of the tail cylinder inner cylinder 12 are provided.

  In FIG. 1, the intake air 15 becomes high-pressure air 16 after being compressed by the compressor 1. After the high pressure air 16 is filled in the casing 4, it flows into the space between the tail cylinder inner cylinder 12 and the tail cylinder outer cylinder 13, and convectively cools the tail cylinder inner cylinder 12 from the outer wall surface.

  High-pressure air 16 convectively cooled from the outer wall surface of the tail cylinder inner cylinder 12 flows toward the head of the combustor 2 through an annular flow path formed between the flow sleeve 11 and the combustor liner 10. The high-pressure air 16 is used for convective cooling of the combustor liner 10 while flowing.

  A part of the high-pressure air 16 flows into the combustor liner 10 from a large number of cooling holes (not shown) provided in the combustor liner 10 and is used for film cooling of the combustor liner 10.

  Among the high-pressure air 16, the remaining high-pressure air 16 that has not been used for cooling the film of the combustor liner 10 is a large number of air provided in the air hole plate 31 located on the upstream side wall surface of the combustion chamber 5 as combustion air 16A. It flows into the hole 32.

  The combustion air 16A that has flowed into the air hole 32 is either directly jetted into the combustion chamber 5 as an air jet 17 or mixed with the fuel jetted from the fuel nozzle 25 and flows into the combustion chamber 5 as a premixed gas 18, It burns to produce hot combustion gas 19. This high-temperature combustion gas 19 is supplied to the turbine 3 through the transition piece inner cylinder 12.

  The high temperature combustion gas 19 is exhausted after driving the turbine 3 to become exhaust gas 20. The driving force obtained by the turbine 3 is transmitted to the compressor 1 and the generator 8 through the shaft 7. The driving force transmitted to the compressor 1 is used to pressurize air to generate high-pressure air 16, and the driving force transmitted to the generator 8 is converted into electric energy.

  The gas turbine plant 9 includes three fuel systems 51, 52, and 53 for supplying gas fuel 50 to the multi-burner 6. Fuel flow control valves 61 to 63 are provided in the fuel systems 51 to 53, respectively. The power generation amount of the gas turbine plant 9 is controlled by controlling the flow rate of each fuel system. Specifically, it is controlled by adjusting the valve opening degree of the fuel flow rate adjusting valves 61 to 63 by a command signal from the control device 65. The three fuel systems 51, 52, 53 are joined upstream, and a fuel cutoff valve 60 for shutting off the fuel is provided in this joining pipe.

  Next, the burner structure will be described with reference to FIGS. FIG. 2 is a schematic configuration diagram showing a side sectional view of a main part of the first embodiment of the gas turbine combustor and the control method thereof according to the present invention, together with a situation diagram showing a flow of combustion gas in the combustion chamber, 3 is a front view of an example of the air hole plate constituting the first embodiment of the gas turbine combustor and the control method thereof according to the present invention as viewed from the combustion chamber side, and FIG. 4 is the gas turbine combustor according to the present invention and the air turbine plate thereof. FIG. 5 is a schematic configuration diagram showing a detailed side sectional view of an example of the F1 burner constituting the first embodiment of the control method together with a situation diagram showing the flow of combustion gas in the combustion chamber, and FIG. 5 is a gas turbine of the present invention It is a characteristic view which shows the flame form at the time of starting / acceleration of F1 burner which comprises 1st Embodiment of a combustor and its control method. 2 to 5, the same reference numerals as those shown in FIG. 1 are the same parts, and detailed description thereof is omitted.

  As shown in FIGS. 2 and 3, the multi-burner 6 in the present embodiment includes an activation F1 burner 66 disposed at the center in the axial direction of the combustor 5 and six concentric circles disposed on the outer periphery thereof. F2 burner 67 is comprised.

  Each of the burners 66 and 67 has a number of fuel nozzles 25, a fuel header 23 that distributes fuel to the number of fuel nozzles 25, and an air hole 32 through which air and fuel pass in a one-to-one correspondence with the fuel nozzle 25. It is a burner provided with the air hole plate 31 made.

  Further, as shown in FIG. 3, the air holes 32 provided in the air hole plate 31 of each burner 66, 67 are provided on three rows of concentric circles centering on the axis of each burner. The F1 burner 66 is divided into an F1 burner inner peripheral portion 66a including the axis of the F1 burner 66 and an F1 burner outer peripheral portion 66b arranged around the F1 burner inner peripheral portion 66b. In the present embodiment, the F1 burner inner peripheral portion 66a is The first row from the axial center of the air holes 32 is included, and the F1 burner outer peripheral portion 66b includes the second and third rows of the air holes 32.

  In order to stably burn a wide range of operating conditions from startup to rated load conditions, the gas turbine is operated by the F1 burner 66 alone at startup and under low load conditions, and the number of F2 burners 67 that supply fuel increases as the load increases. Finally, supply fuel to all burners and operate. By performing such an operation, the flame 42 can be stably held by maintaining the fuel-air ratio in each burner at a certain level or more.

  4, the F1 burner inner peripheral portion 66a includes an inner peripheral fuel nozzle 25a, an inner peripheral air hole 32a, and an inner peripheral orifice 22a that allows the fuel header 23 and the inner peripheral fuel nozzle 25a to communicate with each other. Further, the F1 burner outer peripheral portion 66b includes an outer peripheral fuel nozzle 25b, an outer peripheral air hole 32b, and an outer peripheral orifice 22b that communicates the fuel header 23 and the outer peripheral fuel nozzle 25b.

  The air holes 32 a and 32 b provided in the air hole plate 31 are inclined with respect to the burner central axis 44. As a result, a burner circumferential velocity component is imparted to the premixed gas jet 18, and a swirling flow 40 that swirls while spreading outward is formed downstream of the burner. As a result, a circulating flow 41 is formed at the center of the burner. Since the high-temperature combustion gas returns from the downstream of the combustion chamber 5 to the vicinity of the outlets of the air holes 32a and 32b by the circulation flow 41, the flame 42 can be stably held.

Next, the flame form with respect to the local fuel-air ratio of F1 burner 66 is demonstrated using FIG.4 and FIG.5.
First, the flow rate of fuel supplied to the inner peripheral fuel nozzle 25a of the F1 burner inner peripheral portion 66a shown in FIG. 4 is defined as F1in, and the amount of air flowing into the inner peripheral air hole 32a is defined as A1in. The flow rate of fuel supplied to the peripheral fuel nozzle 25b is defined as F1out, and the amount of air flowing into the peripheral air hole 32b is defined as A1out. The local fuel / air ratio at the outlet of the inner peripheral air hole 32a of the F1 burner 66 is defined as F1in / A1in, and the local fuel / air ratio at the outlet of the outer peripheral air hole 32b of the F1 burner 66 is defined as F1out / A1out.

  In FIG. 5, the horizontal axis indicates the local fuel-air ratio F1in / A1in at the outlet of the inner peripheral air hole 32a of the F1 burner 66, and the vertical axis indicates the local fuel-air ratio at the outlet of the outer peripheral air hole 32b of the F1 burner 66 as F1out / A1out. Show. A line 111 indicated by a one-dot chain line indicates a stoichiometric mixture ratio condition of the F1 burner inner peripheral portion 66a, and a line 112 indicated by a one-dot chain line indicates a stoichiometric mixture ratio condition of the F1 burner outer peripheral portion 66b.

  A premixed flame that burns in a premixed state of fuel and air has the fastest combustion speed (the speed at which the flame propagates the premixed gas) near the stoichiometric mixture ratio condition. As the gas becomes thinner or thicker, the combustion speed becomes slower, and when a certain ratio is reached, the point where the flow velocity of the premixed gas jet and the combustion speed balance does not exist near the outlet of the air hole, or the flame is lifted, or Misfire. In FIG. 5, this constant ratio is indicated by an inner peripheral lower limit line 101 as a decrease in the F1 burner inner peripheral portion 66 a side, and an inner peripheral upper limit line 102 as an upper limit. Similarly, a lowering of the F1 burner outer peripheral portion 66b side is indicated by an outer peripheral lower limit line 103, and an upper limit is indicated by an outer peripheral upper limit line 104.

  For this reason, the conditions for the flame 42 to hold the flame at the outlet of the inner peripheral air hole 32a of the F1 burner are limited to the two lines of the inner peripheral lower limit line 101 and the inner peripheral upper limit line 102. Similarly, the conditions for the flame 42 to hold the flame at the outlet of the F1 burner outer peripheral air hole 32b are limited between the outer peripheral lower limit line 103 and the outer peripheral upper limit line 104.

  Whether or not the flame 42 can be held near the air hole outlet is dominated by the fuel-air ratio of the premixed gas, but the premixed airflow ejected from the adjacent air holes leaks, The inner circumference upper limit line 102 and the inner circumference lower limit line 101 are gradually shifted to lower values of F1in / A1in as F1out / A1out is higher. Similarly, the outer circumference upper limit line 104 and the outer circumference lower limit line 103 are F1in. As / A1in is higher, the value is shifted to a lower value of F1out / A1out.

  In FIG. 5, in the range surrounded by the inner peripheral upper limit line 102, the inner peripheral lower limit line 101, the outer peripheral upper limit line 104, and the outer peripheral lower limit line 103, flames are held at the outlets of all the air holes. For this reason, even when the F1 burner 66 burns alone as in the start / up speed shown in FIG. 2, even if the air jet 17 from the F2 burner 67 flows downstream of the F1 burner 66, the F1 burner 66 The premixed gas jet 18 sufficiently undergoes a combustion reaction and can suppress the discharge of unburned matter.

  On the other hand, in the condition 105 in which the F1 burner inner peripheral portion local fuel-air ratio and the F1 burner outer peripheral portion local fuel-air ratio in FIG. 5 are substantially equal, the F1 burner 66 has the same flame formation position and the local fuel-air ratio is the same. Because it is almost the same, the flame tends to fluctuate uniformly. For this reason, when the flame fluctuates, the pressure in the combustion chamber 5 fluctuates, the flow rate of the fuel supplied to the F1 burner 66 fluctuates due to the pressure fluctuation of the combustion chamber 5, and the flame fluctuates further. As a result, there is a possibility that the pressure fluctuation and the flame fluctuation are amplified to each other and combustion vibration is generated.

  Therefore, if the F1 burner 66 is operated while avoiding the proximity condition 105 of F1in / A1in = F1out / A1out, the occurrence of combustion vibration can be avoided. Specifically, when the local fuel-air ratio is offset between the F1 burner inner peripheral portion 66a and the F1 burner outer peripheral portion 66b, a difference in combustion speed occurs between the inner peripheral portion and the outer peripheral portion, and the flame changes. The fluctuation time when the pressure fluctuates as the flame fluctuates. As a result, it is possible to prevent the inner peripheral portion and the outer peripheral portion from fluctuating in the same cycle, so that combustion vibration is suppressed.

  Next, F1in / A1in is within the range of the inner circumference upper limit line 102 and the inner circumference lower limit line 101, and F1out / A1out is higher than the outer circumference upper limit line 104 or lower than the outer circumference lower limit line 103. 6 will be described. FIG. 6 is another example of FIG. 2, and in the F1 burner, together with a situation diagram showing a flame form when the fuel cost of the outer periphery is lower than the fuel cost that can hold the flame at the air hole outlet FIG. In FIG. 6, the same reference numerals as those shown in FIGS. 1 to 5 are the same parts, and detailed description thereof is omitted.

  In this case, while a flame is held at the inner peripheral air hole outlet, a flame is not held around the outer peripheral air hole outlet, so that a conical flame 42 is formed as shown in FIG. For this reason, when F1out / A1out is lower than the outer peripheral lower limit line 103, when the F1 burner 66 is burned alone as in the startup / acceleration, the premixed gas jetted from the outer peripheral air hole of the F1 burner 66 The jet 18 is diluted by the air jet 17 ejected from the F2 burner 67 before the combustion reaction proceeds sufficiently. As a result, the fuel-air ratio further decreases, the combustion reaction does not proceed, and a large amount of unburned matter is generated.

  On the other hand, when F1out / A1out is higher than the outer peripheral upper limit line 104, the combustion reaction proceeds even if diluted by the air jet 17 ejected from the F2 burner 67 before the combustion reaction sufficiently proceeds. Therefore, the premixed gas jet 18 ejected from the outer peripheral air hole by the combustion gas of the flame formed at the outlet of the inner peripheral air hole also undergoes the combustion reaction, and the unburned component Emissions are suppressed.

  Next, F1out / A1out shown in FIG. 5 is within the range of the outer peripheral upper limit line 104 and the outer peripheral lower limit line 103, and F1in / A1in is higher than the inner peripheral upper limit line 102 or higher than the inner peripheral lower limit line 101. When it is low, the flame is held at the outer peripheral air hole outlet, while the flame is not held around the inner peripheral air hole outlet. For this reason, the flame which the inner peripheral part floated is formed. However, even if the inner periphery rises, the surroundings are surrounded by a flame that holds the flame at the F1 burner outer periphery air hole outlet, so the combustion reaction proceeds with the high-temperature combustion gas and the discharge of unburned matter is suppressed. Is done.

  On the other hand, whether F1in / A1in shown in FIG. 5 is higher than the inner peripheral upper limit line 102, lower than the inner peripheral lower limit line 101, and F1out / A1out is higher than the outer peripheral upper limit line 104, or the outer peripheral lower limit line. If it is lower than 103, the flame cannot be held at the air hole outlet, and it may misfire or lift, and if it is lifted, the flame position may not be determined and a large pressure fluctuation may occur.

  From the above description of the flame form with respect to the local fuel-air ratio of the F1 burner 66, the local fuel-air ratio of the F1 burner 66 is set to the inside of the stable combustion range 107 and the inside of the stable combustion range 108 shown in FIG. Generation of fuel and combustion vibrations can be suppressed, and combustion can be performed stably.

  Further, in the stable combustion range 107 where F1in / A1in <F1out / A1out, even if F1in / A1in is lower than the inner peripheral lower limit line 101, F1out / A1out falls between the outer peripheral upper limit line 104 and the outer peripheral lower limit line 103. If it does, it can combust stably, suppressing discharge | emission of an unburned part. For this reason, the stable combustion range 107 can be stably burned in a wider range than the stable combustion range 108, and the operability of the F1 burner 66 can be further improved.

  When operating in the stable combustion range 107, the range in which F1out / A1out can be operated is wider than F1in / A1in. In the present embodiment, as shown in FIG. 3, the number of air holes in the F1 burner outer peripheral portion 66b is increased with respect to the F1 burner inner peripheral portion 66a, and the total amount of air flowing into the F1 burner outer peripheral portion 66b is increased. . For this reason, the flow range of F1out in which the F1 burner 66 can be stably operated can be expanded, and the combustion load amount of the entire F1 burner 66 can be set in a wide range. As a result, the operability of the F1 burner 66 can be improved.

Next, returning to FIG. 4, the setting of the local fuel-air ratio of the F1 burner 66 will be described.
The F1 burner 66 in the present embodiment, as shown in FIG. 4, is a fuel supplied to an inner peripheral fuel nozzle 25a corresponding to the F1 burner inner peripheral portion 66a and an outer peripheral fuel nozzle 25b corresponding to the F1 burner outer peripheral portion 66b. In order to adjust the distribution, an inner peripheral orifice 22a and an outer peripheral orifice 22b are provided.

  Here, when the diameter of the inner peripheral orifice 22a provided in the inner peripheral fuel nozzle 25a is defined as Din and the diameter of the outer peripheral orifice 22b provided in the outer peripheral fuel nozzle 25b is defined as Dout, in this embodiment, Din <Dout. It is set as follows.

  As shown in FIG. 4, since the inner peripheral fuel nozzle 25a and the outer peripheral fuel nozzle 25b are connected to the same fuel header 23, F1in <F1out. On the other hand, since the diameter Dain of the inner peripheral air hole 32a arranged in the F1 burner inner peripheral part 66a and the diameter Daout of the outer peripheral air hole 32b arranged in the F1 burner inner peripheral part 66b have the same diameter, each air hole 32a, The amount of air A1in and A1out flowing into 32b is the same value. As a result, according to the configuration of the present embodiment, F1in / A1in <F1out / A1out.

  When the local fuel-air ratio of the F1 burner 66 is set to satisfy F1in / A1in <F1out / A1out with the diameters of the orifices 22a and 22b provided in the fuel nozzles 25a and 25b as in the present embodiment, each fuel nozzle The flow distribution of the air holes is always constant. For this reason, for example, the fuel-air ratio condition of the F1 burner 66 can be set on the F1 burner operation line 109 shown in FIG. 5, and the stable combustion range 110 among them allows stable combustion while suppressing the discharge of unburned fuel. be able to.

  Next, another example of setting the local fuel-air ratio of the F1 burner 66 will be described with reference to FIGS. 7 is a detailed side sectional view showing another example of the F1 burner constituting the first embodiment of the gas turbine combustor and its control method of the present invention, and FIG. 8 is another example of the F1 burner shown in FIG. It is the front view which looked at from the combustion chamber side. 7 and 8, the same reference numerals as those shown in FIGS. 1 to 6 are the same parts, and detailed description thereof is omitted.

  As shown in FIGS. 7 and 8, as another example of setting the local fuel-air ratio of the F1 burner 66, the diameters of the orifices 22a and 22b provided in the fuel nozzles 25a and 25b are the same on the inner periphery and the outer periphery. While the fuel flow rate supplied per fuel nozzle is the same, the diameter Dain of the inner peripheral air hole 32a may be larger than the diameter Daout of the outer peripheral air hole 32b. Even in this case, it is possible to satisfy F1in / A1in <F1out / A1out by making the amount of air flowing into the inner peripheral air hole larger than the amount of air flowing into the outer peripheral air hole.

  In the case where the fuel nozzles 25a and 25b are inserted into the air holes as in the present embodiment, in addition to changing the air hole diameter, the outer diameters of the fuel nozzles 25a and 25b are changed as means for adjusting the inflow amount of air. Also good. In order to satisfy F1in / A1in <F1out / A1out, for example, when the air hole diameter and the orifice diameter of the fuel nozzle are constant, the outer diameter of the front end portion of the inner peripheral fuel nozzle 25a of the F1 burner is set to the end portion of the outer peripheral fuel nozzle 25b. The flow path cross-sectional area of the inner peripheral air hole 32a may be larger than the flow path cross-sectional area of the outer peripheral air hole 32b.

  According to the first embodiment of the gas turbine combustor and its control method of the present invention described above, since it is possible to suppress discharge of unburned fuel and combustion vibration at the time of start-up / acceleration of the gas turbine, The operating range of the F1 burner 66 for use can be expanded. As a result, it is possible to provide a gas turbine combustor that can stably increase the rotational speed of the gas turbine and a control method therefor.

  Further, according to the first embodiment of the gas turbine combustor and the control method thereof according to the present invention described above, the number of fuel systems is small, and the unburned portion at the time of start-up / acceleration of the gas turbine is achieved with a simple structure. Discharge and combustion vibration can be suppressed.

  The second embodiment of the gas turbine combustor and the control method thereof according to the present invention will be described below with reference to the drawings. FIG. 9 is a schematic configuration diagram showing a side sectional view of a main part of a gas turbine combustor and a control method thereof according to the second embodiment of the present invention together with a situation diagram showing a flow of combustion gas in the combustion chamber, 10 is a front view of an example of an air hole plate constituting the second embodiment of the gas turbine combustor and the control method thereof according to the present invention viewed from the combustion chamber side, and FIG. 11 is the gas turbine combustor of the present invention and the air turbine plate thereof. It is a characteristic view which shows the flame form at the time of all the burner flame formation of F1 burner which comprises 2nd Embodiment of a control method. 9 to 11, the same reference numerals as those shown in FIGS. 1 to 8 are the same parts, and thus detailed description thereof is omitted.

  The second embodiment of the gas turbine combustor and the control method thereof according to the present invention shown in FIGS. 9 and 10 is composed of almost the same equipment as the first embodiment, but differs in the following construction. In the present embodiment, in the F1 burner 66, the fuel header 23 is divided into an inner peripheral fuel header 23a and an outer peripheral fuel header 23b. The inner peripheral fuel header 23a supplies fuel to the inner peripheral fuel nozzle 25a corresponding to the F1 burner inner peripheral portion 66a, and is connected to an inner peripheral fuel system 51a provided with an inner peripheral fuel flow rate adjustment valve 61a. Yes. Similarly, the outer peripheral fuel header 23b supplies fuel to the outer peripheral fuel nozzle 25b corresponding to the F1 burner outer peripheral portion 66b, and is connected to an outer peripheral fuel system 51b provided with an outer peripheral fuel flow rate adjusting valve 61b.

  The control device 65 individually adjusts the opening of the inner peripheral fuel flow rate adjustment valve 61a and the outer peripheral fuel flow rate adjustment valve 61b, so that the fuel flow rate supplied to the F1 burner inner peripheral portion 66a and the F1 burner outer peripheral portion 66b is adjusted. Can be controlled separately.

  In this embodiment, since the local fuel-air ratio between the F1 burner inner peripheral portion 66a and the F1 burner outer peripheral portion 66b can be adjusted by the control device 65 in this way, as in the first embodiment. Further, it is not necessary to change the diameters of the orifices 22a and 22b and the air holes 32a and 32b provided in the fuel nozzles 25a and 25b between the F1 burner inner peripheral portion 66a and the F1 burner outer peripheral portion 66b.

  Also in this embodiment, the flame form of the F1 burner 66 can be organized by the characteristics shown in FIG. The conditions for holding the flame at the outlet of the inner peripheral air hole 32a of the F1 burner are limited to the two lines of the inner peripheral lower limit line 101 and the inner peripheral upper limit line 102 shown in FIG. The condition that the flame is held at the outlet of the air hole 32b is limited to between the outer peripheral portion lower limit line 103 and the outer peripheral portion upper limit line 104.

  On the other hand, in the range surrounded by the inner peripheral upper limit line 102, the inner peripheral lower limit line 101, the outer peripheral upper limit line 104, and the outer peripheral lower limit line 103, flames are held at the outlets of all the air holes. For this reason, even when the F1 burner 66 alone burns at the time of turbine start-up / acceleration, even if the air jet 17 from the F2 burner 67 flows downstream of the F1 burner 66 as shown in FIG. The premixed gas jet 18 from the burner 66 has a sufficiently advanced combustion reaction and can suppress the discharge of unburned matter.

  However, under the condition 105 in which the F1 burner inner periphery local fuel / air ratio F1in / A1in and the F1 burner outer periphery local fuel / air ratio F1out / A1out in FIG. 5 substantially coincide with each other, as in the case of the first embodiment, F1 Since the flame formation position is the same in the entire burner 66 and the local fuel-air ratio is substantially the same, the flame is likely to fluctuate uniformly. For this reason, when the flame fluctuates, the pressure in the combustion chamber 5 fluctuates, the flow rate of the fuel supplied to the F1 burner 66 fluctuates due to the pressure fluctuation of the combustion chamber 5, and the flame fluctuates further. As a result, there is a possibility that the pressure fluctuation and the flame fluctuation are amplified to each other and combustion vibration is generated.

  Therefore, in the present embodiment, the opening degree of the inner peripheral fuel flow rate adjusting valve 61a and the outer peripheral fuel flow rate adjusting valve 61b is adjusted to avoid the proximity condition 105 of F1in / A1in = F1out / A1out and the F1 burner 66. Can be used to avoid the occurrence of combustion vibration. Specifically, when the local fuel-air ratio is offset between the F1 burner inner peripheral portion 66a and the F1 burner outer peripheral portion 66b, a difference in combustion speed occurs between the inner peripheral portion and the outer peripheral portion, and the flame changes. The fluctuation time when the pressure fluctuates as the flame fluctuates. As a result, it is possible to prevent the inner peripheral portion and the outer peripheral portion from fluctuating in the same cycle, so that combustion vibration is suppressed.

  Next, a case where F1in / A1in is within the range of the inner periphery upper limit line 102 and the inner periphery lower limit line 101 and F1out / A1out is higher than the outer periphery upper limit line 104 or lower than the outer periphery lower limit line 103 will be described. To do. In this case, a flame is held at the inner peripheral air hole outlet, whereas a flame is not held around the outer peripheral air hole outlet, so that a conical flame is formed. For this reason, when F1out / A1out is lower than the outer peripheral lower limit line 103, when the F1 burner 66 is burned alone as in the startup / acceleration, the premixed gas jetted from the outer peripheral air hole of the F1 burner 66 The jet 18 is diluted by the air jet 17 ejected from the F2 burner 67 before the combustion reaction proceeds sufficiently. As a result, the fuel-air ratio further decreases, the combustion reaction does not proceed, and a large amount of unburned matter is generated.

  On the other hand, when F1out / A1out is higher than the outer peripheral upper limit line 104, the combustion reaction proceeds even if diluted by the air jet 17 ejected from the F2 burner 67 before the combustion reaction sufficiently proceeds. Therefore, the premixed gas jet 18 ejected from the outer peripheral air hole by the combustion gas of the flame formed at the outlet of the inner peripheral air hole also undergoes the combustion reaction, and the unburned component Emissions are suppressed.

  Next, F1out / A1out shown in FIG. 5 is within the range of the outer peripheral upper limit line 104 and the outer peripheral lower limit line 103, and F1in / A1in is higher than the inner peripheral upper limit line 102 or higher than the inner peripheral lower limit line 101. When it is low, the flame is held at the outer peripheral air hole outlet, while the flame is not held around the inner peripheral air hole outlet. For this reason, the flame which the inner peripheral part floated is formed. However, even if the inner periphery rises, the surroundings are surrounded by a flame that holds the flame at the F1 burner outer periphery air hole outlet, so the combustion reaction proceeds with the high-temperature combustion gas and the discharge of unburned matter is suppressed. Is done.

  On the other hand, whether F1in / A1in shown in FIG. 5 is higher than the inner peripheral upper limit line 102, lower than the inner peripheral lower limit line 101, and F1out / A1out is higher than the outer peripheral upper limit line 104, or the outer peripheral lower limit line. If it is lower than 103, the flame cannot be held at the air hole outlet, and it may misfire or lift, and if it is lifted, the flame position may not be determined and a large pressure fluctuation may occur.

From the above description of the flame form with respect to the local fuel-air ratio of the F1 burner 66, the local fuel-air ratio of the F1 burner 66 is set to the inside of the stable combustion range 107 and the inside of the stable combustion range 108 shown in FIG. Generation of fuel and combustion vibrations can be suppressed, and combustion can be performed stably.
Further, in the stable combustion range 107 where F1in / A1in <F1out / A1out, even if F1in / A1in is lower than the inner peripheral lower limit line 101, F1out / A1out falls between the outer peripheral upper limit line 104 and the outer peripheral lower limit line 103. If it does, it can combust stably, suppressing discharge | emission of an unburned part. For this reason, the stable combustion range 107 can be stably burned in a wider range than the stable combustion range 108, and the operability of the F1 burner 66 can be further improved.

  When operating in the stable combustion range 107, the range in which F1out / A1out can be operated is wider than F1in / A1in. In the present embodiment, as in the first embodiment, as shown in FIG. 10, the number of air holes in the F1 burner outer peripheral portion 66b is made larger than the number of air holes in the F1 burner inner peripheral portion 66a, and the F1 burner outer peripheral portion The total amount of air flowing into 66b is increased. For this reason, the flow range of F1out in which the F1 burner 66 can be stably operated can be expanded, and the combustion load amount of the entire F1 burner 66 can be set in a wide range. As a result, the operability of the F1 burner 66 can be improved.

  Next, the flame form of the F1 burner when all the burner flames are formed will be described. At the time of turbine startup / acceleration described in the first embodiment, F1in / A1in is within the range of the inner peripheral upper limit line 102 and the inner peripheral lower limit line 101 shown in FIG. 5, and F1out / A1out is the outer peripheral lower limit. If it is smaller than the line 103, a large amount of unburned matter is generated as described above. However, when a flame is formed in all of the F2 burner 67 such as the rated load condition, the premixed gas 18 ejected from the outer peripheral air hole 32b of the F1 burner is diluted and a large amount of unburned fuel is produced. Since it is not discharged, it can be stably burned even under such conditions.

  FIG. 11 shows the flame form of the F1 burner when such all-burner flame is formed. As shown in FIG. 11, the stable combustion range 108 of F1in / A1in> F1out / A1out is expanded as compared with the stable combustion range 108 at the time of startup / acceleration shown in FIG.

  In the present embodiment, the opening area of the inner peripheral air hole 32a arranged in the F1 burner inner peripheral part 66a is made smaller than the opening area of the outer peripheral air hole 32b arranged in the F1 burner outer peripheral part 66b, and the inner periphery of the F1 burner The ratio of the fuel supplied to the fuel nozzle 25a and the outer peripheral fuel nozzle 25b of the F1 burner can be freely changed. As a result, under the rated load condition, the premixed gas amount that increases the fuel-air ratio can be minimized by operating within the stable combustion range 108 shown in FIG. 11 and satisfying F1in / A1in> F1out / A1out. . As a result, the NOx emission amount can be minimized.

  According to the second embodiment of the gas turbine combustor and its control method of the present invention described above, the same effects as in the first embodiment can be obtained.

  Further, according to the second embodiment of the gas turbine combustor and the control method thereof according to the present invention described above, the fuel distribution supplied to the inner peripheral portion and the outer peripheral portion of the F1 burner 66 is distributed to the inner peripheral fuel flow rate adjusting valve 61a. Therefore, the stable combustion range 108 at the time of start-up / acceleration can be secured, and operation in the expanded stable combustion range 108 is possible even under rated load conditions. Become. As a result, the NOx emission amount can be minimized in the entire operation range.

  In addition, this invention is not limited to an above-described Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Each of the above-described configurations, functions, and the like may be realized by software by interpreting and executing a program that realizes each function by the processor.

DESCRIPTION OF SYMBOLS 1 Compressor 2 Combustor 3 Turbine 4 Casing 5 Combustion chamber 6 Multi burner 7 Shaft 8 Generator 9 Gas turbine plant 10 Combustor liner 11 Flow sleeve 12 Cylinder inner cylinder 13 Cylinder outer cylinder 15 Suction air 16 High pressure air 17 Air Jet 18 Premixed gas jet 19 High temperature combustion gas 20 Exhaust gas 22 Orifice 22a Inner peripheral orifice 22b Outer peripheral orifice 23 Fuel header 23a Inner peripheral fuel header 23b Outer peripheral fuel header 25 Fuel nozzle 25a Inner peripheral fuel nozzle 25b Outer peripheral fuel nozzle 31 Air hole plate 32 Air hole 32a Inner peripheral air hole 32b Outer peripheral air hole 40 Swirling flow 41 Circulating flow 42 Flame 44 Burner central shaft 50 Gas fuel 51 Fuel system 51a First fuel system 51b Second fuel system 52, 53 Fuel system 60 Fuel shut-off valve 61 Fuel flow control valve 61a First fuel flow rate Adjusting valve 61b Second fuel flow rate adjusting valve 62, 63 Fuel flow rate adjusting valve 65 Control device 66 F1 burner 66a F1 burner inner periphery 66b F1 burner outer periphery 67 F2 burner 101 F1 burner inner periphery local fuel-air ratio lower limit line 102 F1 Burner inner periphery local fuel-air ratio upper limit line 103 F1 burner outer periphery local fuel-air ratio lower limit line 104 F1 burner outer periphery local fuel-air ratio upper limit line 105 F1 burner inner periphery local fuel-air ratio and outer periphery local fuel-air ratio Equal condition 107 Stable combustion region 108 Stable combustion region 109 F1 burner operation line 110 F1 burner stable combustion operation range 111 F1 burner inner periphery stoichiometric mixture ratio condition 112 F1 burner outer periphery stoichiometric mixture ratio condition

Claims (8)

A cylindrical combustion chamber in which the supplied fuel and supplied air are mixed and burned, and an air hole plate which is located upstream of the combustion chamber and has a plurality of air holes for supplying air to the combustion chamber A plurality of fuel nozzles that are arranged upstream of the air hole plate and supply the fuel to a plurality of air holes formed in the air hole plate, and the plurality of fuel nozzles and the plurality of air holes respectively A plurality of burners arranged so as to be, an F1 burner for activation arranged at the axial center of the air hole plate facing the combustion chamber among the plurality of burners, and an outer periphery of the F1 burner In the gas turbine combustor provided with a plurality of F2 burners arranged in the section,
The fuel nozzles and the air holes of the F1 burner are arranged on a plurality of rows of circles, and the air holes of the F1 burner are arranged on the radially inner side and the inner peripheral part air holes. An outer peripheral air hole arranged on the outer peripheral side of the
The F1 burner includes an inner peripheral fuel nozzle disposed corresponding to the inner peripheral air hole, an outer peripheral fuel nozzle disposed corresponding to the outer peripheral air hole, and the inner peripheral fuel nozzle. A fuel header that supplies fuel to the outer peripheral fuel nozzle, an inner peripheral orifice that communicates the fuel header and the inner peripheral fuel nozzle, and an outer peripheral orifice that communicates the fuel header and the outer peripheral fuel nozzle; With
Rather smaller than the diameter of the inner peripheral orifice diameter of the outer peripheral orifice, fuel-air ratio at the exit of the inner peripheral portion air holes may be smaller than the fuel-air ratio at the exit of the outer peripheral portion air hole Gas turbine combustor. A cylindrical combustion chamber in which the supplied fuel and supplied air are mixed and burned, and an air hole plate which is located upstream of the combustion chamber and has a plurality of air holes for supplying air to the combustion chamber A plurality of fuel nozzles that are arranged upstream of the air hole plate and supply the fuel to a plurality of air holes formed in the air hole plate, and the plurality of fuel nozzles and the plurality of air holes respectively A plurality of burners arranged so as to be, an F1 burner for activation arranged at the axial center of the air hole plate facing the combustion chamber among the plurality of burners, and an outer periphery of the F1 burner In the gas turbine combustor provided with a plurality of F2 burners arranged in the section,
The fuel nozzles and the air holes of the F1 burner are arranged on a plurality of rows of circles, and the air holes of the F1 burner are arranged on the radially inner side and the inner peripheral part air holes. An outer peripheral air hole arranged on the outer peripheral side of the
The diameter of the inner peripheral portion air hole of the F1 burner, the F1 burner outer peripheral portion much larger than the diameter of the air holes of the fuel-air ratio at the exit of the inner peripheral portion air hole, at the outlet of the outer peripheral portion air hole A gas turbine combustor characterized by being smaller than a fuel-air ratio . A cylindrical combustion chamber in which the supplied fuel and supplied air are mixed and burned, and an air hole plate which is located upstream of the combustion chamber and has a plurality of air holes for supplying air to the combustion chamber A plurality of fuel nozzles that are arranged upstream of the air hole plate and supply the fuel to a plurality of air holes formed in the air hole plate, and the plurality of fuel nozzles and the plurality of air holes respectively A plurality of burners arranged so as to be, an F1 burner for activation arranged at the axial center of the air hole plate facing the combustion chamber among the plurality of burners, and an outer periphery of the F1 burner In the gas turbine combustor provided with a plurality of F2 burners arranged in the section,
The fuel nozzles and the air holes of the F1 burner are arranged on a plurality of rows of circles, and the air holes of the F1 burner are arranged on the radially inner side and the inner peripheral part air holes. An outer peripheral air hole arranged on the outer peripheral side of the
The plurality of air holes are respectively inserted with tips of the plurality of fuel nozzles,
The F1 burner includes an inner peripheral fuel nozzle arranged corresponding to the inner peripheral air hole, and an outer peripheral fuel nozzle arranged corresponding to the outer peripheral air hole,
The outer diameter of the distal end portion of the inner peripheral portion the fuel nozzle of the F1 burner, the rather smaller than the outer diameter of the distal end portion of the outer peripheral portion the fuel nozzle of F1 burners, fuel-air ratio at the exit of the inner peripheral portion air holes, The gas turbine combustor characterized by being smaller than the fuel-air ratio in the exit of the said outer peripheral part air hole . The gas turbine combustor according to any one of claims 1 to 3, the total opening area of the inner peripheral portion air hole of the F1 burners is smaller than the total opening area of the outer peripheral portion air hole of the F1 burner A gas turbine combustor. A cylindrical combustion chamber in which the supplied fuel and supplied air are mixed and burned, and an air hole plate which is located upstream of the combustion chamber and has a plurality of air holes for supplying air to the combustion chamber A plurality of fuel nozzles that are arranged upstream of the air hole plate and supply the fuel to a plurality of air holes formed in the air hole plate, and the plurality of fuel nozzles and the plurality of air holes respectively A plurality of burners arranged so as to be, an F1 burner for activation arranged at the axial center of the air hole plate facing the combustion chamber among the plurality of burners, and an outer periphery of the F1 burner In the gas turbine combustor provided with a plurality of F2 burners arranged in the section,
The fuel nozzles and the air holes of the F1 burner are arranged on a plurality of rows of circumferences, and an F1 burner inner circumferential portion disposed on the radially inner side and an F1 disposed on the outer circumferential side of the F1 burner inner circumferential portion. It has a burner outer peripheral portion,
A first fuel system for supplying the fuel to a fuel nozzle in the inner periphery of the F1 burner;
A second fuel system for supplying the fuel to a fuel nozzle on the outer periphery of the F1 burner;
A first flow rate adjusting valve provided in the first fuel system for adjusting a fuel flow rate;
A second flow rate adjusting valve provided in the second fuel system for adjusting the fuel flow rate;
At the time of starting / accelerating the gas turbine, the fuel / air ratio at the outlet of the air hole in the inner peripheral portion of the F1 burner is smaller than the fuel / air ratio at the outlet of the air hole in the outer peripheral portion of the F1 burner. A gas turbine combustor comprising a control device for controlling a flow rate adjustment valve and an opening degree of the second flow rate adjustment valve. 6. The gas turbine combustor according to claim 5 , wherein the control device determines a fuel supply amount per one fuel nozzle in an inner peripheral portion of the F1 burner when the gas turbine is started / accelerated. A gas turbine combustor, wherein the opening amounts of the first flow rate adjustment valve and the second flow rate adjustment valve are controlled so as to be smaller than a fuel supply amount per one fuel nozzle in an outer peripheral portion. The gas turbine combustor according to claim 5 or 6, gas the total opening area of the inner peripheral portion air holes of F1 burners may be smaller than the total opening area of the outer peripheral portion air hole of the F1 burner Turbine combustor. A cylindrical combustion chamber for mixing and burning the supplied fuel and the supplied air;
An air hole plate which is located upstream of the combustion chamber and has a plurality of air holes for supplying air to the combustion chamber, and a plurality of air holes which are arranged on the upstream side of the air hole plate and formed in the air hole plate A plurality of fuel nozzles for supplying the fuel, a plurality of burners configured such that the plurality of fuel nozzles and the plurality of air holes are in pairs, and the combustion among the plurality of burners In a control method of a gas turbine combustor comprising a starting F1 burner arranged at the axial center of the air hole plate facing a chamber, and a plurality of F2 burners arranged on the outer periphery of the F1 burner,
The fuel nozzles and the air holes of the F1 burner are arranged on a plurality of rows of circles, and the local fuel-air ratio on the radially outer side at the outlet of the F1 burner is determined as the F1 when the gas turbine starts up / accelerates. A control method for a gas turbine combustor, wherein the operation is performed at a higher ratio than a local fuel-air ratio radially inward at an outlet of a burner.

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