JP2006010193A - Gas turbine combustor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas turbine combustor for reducing discharge of a toxic component over a wide range, superior in combustion stability, superior in uniformity of the gas temperature distribution of a combustor outlet, having the short length, and having a large spatial combustion load. <P>SOLUTION: An air-fuel mixture injector 57 injects a fuel-air mixture into a burnt gas flow generated in an upstream combustion area and flowing toward the downstream side, and is composed of a fuel injector 62, an air swirling means and an air-fuel mixture injection pipe 61, and is installed from the outside on a wall surface of a combustor casing 52. An injection opening of the air-fuel mixture injection pipe 61 is positioned in the vicinity of a wall surface opening of a combustor liner 51. Since the fuel-air mixture is injected so as to cross with burnt gas and is applied with swirling, mixing with the burnt gas is promoted, and generation of NOx by combustion is effectively restrained, and combustion is completed in a short time. Uniformity of the temperature distribution of the combustor outlet is improved, and the service life of a turbine part is lengthened. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a combustor for generating high-temperature combustion gas, and particularly to a combustor for a jet engine or an industrial gas turbine (hereinafter referred to as a gas turbine combustor), and further includes a rated load from a low load. The present invention relates to a gas turbine combustor that enables good combustion and emission performance over a wide operating range up to a high load.

  A combustor with a single combustion region has been widely used as a combustor of a gas turbine, but the fuel-air ratio in the combustion region changes in response to increase or decrease in load, that is, increase or decrease in fuel flow rate. However, the combustion temperature is relatively low at a low load with a low fuel flow rate, and therefore, a large amount of unburned components are generated. On the other hand, the combustion temperature is high at a high load with a high fuel flow rate, and therefore there is a disadvantage that NOx emissions are large. is there. Therefore, if the combustion chamber air distribution is designed so that the combustion area becomes lean at high loads in order to suppress NOx emissions at high loads, the fuel concentration in the combustion areas is too thin at low loads and the unburned components Emissions are likely to increase rapidly. In particular, premixed combustion has a problem that the concentration of the air-fuel mixture becomes lower than the lean combustion limit and ignition is uncertain. Although the above problem is partially solved by adopting a mechanism for controlling the flow rate of air flowing into the combustion region in accordance with the increase or decrease of the fuel flow rate, for example, an air flow rate valve, it alone has the potential of lean premixed combustion over a wide load range. It is difficult to achieve low NOx performance sufficiently. Therefore, a gas turbine that complies with recent strict NOx regulations cannot be realized with a combustor having a single combustion region.

  In order to avoid the above-mentioned problems common to a single combustion zone combustor, multiple combustion zones (or burners) are provided, and the number of combustion zones or the number of burners that supply fuel as the load increases is increased. The method of letting it go is practical. This method is called fuel staging. The fuel flow control for a plurality of burners is a technology that has been established for a long time, and general-purpose control equipment is available, which is low in cost and highly reliable.

  A typical conventional example is illustrated in FIG. In this gas turbine combustor 3, the dome portion 53 a of the combustion chamber 53 formed by the cylindrical combustor liner 51 housed in the cylindrical combustor casing 52 is fully operated from the start to the maximum load. A pilot combustion region 11a having a pilot burner 11 that operates under conditions and a plurality of main burners 12 are arranged, and a main combustion region 12a that increases or decreases the number of operation depending on the magnitude of the load. This is called parallel staging because the pilot and main combustion regions are arranged in parallel. Air or a mixture of air and fuel flows into any combustion region. The pilot burner 11 ensures ignition at start-up, suppresses discharge of unburned components at low loads, and the main burner 12 does not misfire even when the load of the gas turbine in which the fuel flow to the main burner is suddenly reduced. Has the role of In the main combustion region 12a, fuel is supplied to a new main burner in response to an increase in load, the flow rate is increased to the designed flow rate, and further, fuel is supplied to the next main burner. The Air flows out of the non-operating main burner, and this air cools the flame of the adjacent main burner in operation, and if it is excessive, the generation of unburned components increases. is there. In order to avoid this problem, each combustion region and each main burner are often designed to be arranged as far apart as possible within a possible range of fire transfer or separated by a partition wall. The above problem cannot be completely avoided from the essential problem in the case of a single combustion region, although the influence on the emission characteristics of the entire combustor becomes small if the number of main burners is large.

  As an arrangement of the combustion regions in contrast to the parallel staging described above, there is axial (meaning axial direction) staging in which a plurality of combustion regions are arranged in the flow direction (that is, the axial direction of the combustor) in the combustion chamber. The increase in the load corresponds to the increase in the load by supplying fuel or an air-fuel mixture to the downstream combustion region where the burned gas from the upstream combustion region flows and increasing the flow rate thereof. The fuel or fuel-air mixture supplied downstream is injected into the burned gas at a high temperature from the upstream combustion zone and containing a large amount of reaction-active substances. You can react even if you feel like it. Further, when the oxygen concentration in the burned gas is considerably lower than that of air, the generation of NOx is also suppressed. If such a feature can be utilized, there is a high possibility that a gas turbine combustor superior to the parallel staging in which fuel is injected into the air can be realized.

  FIG. 12 is a longitudinal sectional view showing a conventional combustor designed to make maximum use of the characteristics of axial staging (see Patent Document 1). In this gas turbine combustor 4, the pilot burner 11 always operates from the time of starting the engine, and when operating at a predetermined load or higher, in the main combustion region downstream of the pilot combustion region 11 a, the burned gas mass 13 by the pilot burner 11 is formed. On the other hand, the main premixed gas 15 is injected from the main premixed gas injection pipe 14 disposed in the combustion chamber 53 in the axial direction. During operation at a predetermined load or lower, fuel is not supplied to the main premixed gas injection pipe 14, but only air is ejected and mixed with burned gas from the pilot combustion region 11a. The load can be increased or decreased by increasing or decreasing the fuel injection amount to the main premixed gas injection pipe 14. With proper design, it has been demonstrated that almost the entire range from no load to rating can be operated with ultra-low NOx emissions. The important thing is that the pilot burner operates with complete combustion, so that the premixed gas from the main premixed gas injection tube cannot hold the flame by itself, and only reacts or burns when mixed with hot burned gas Is to design. By mixing it with burned gas containing a large amount of reactive substances at high temperatures, even a very fuel-lean mixture that cannot even be ignited can be reacted almost completely with an appropriate residence time. But the combustion efficiency can be kept high. Of course, since this main premixed gas is lean, NOx does not increase by the combustion.

  As another gas turbine that falls into the category of axial staging, a catalytic gas turbine combustor having a reheating fuel nozzle that injects fuel into the combustor liner through the opening of the combustor liner has been proposed ( Patent Document 2). This combustor is a catalytic combustor that burns a premixed mixture prepared by mixing fuel and air with a combustion fuel gas in a preheating chamber. A refueling fuel nozzle that injects fuel into the inner cylinder from an introduction hole that introduces a part of the catalyst into the inner cylinder (burner liner) on the downstream side of the catalyst, and activates this reheating fuel nozzle at high load It has a fuel controller. It is an invention for realizing a gas turbine that requires a combustion fuel gas temperature higher than the heat resistant temperature of the catalyst. Under low load conditions, the fuel is premixed with air and introduced into the catalyst to generate combustion gases. As the flow rate of the premixed fuel is increased as the load increases, the gas temperature immediately downstream of the catalyst also increases accordingly. When this temperature reaches a predetermined temperature determined from the viewpoint of heat resistance and durability of the catalyst, the premixed fuel flow rate is kept constant, and the remaining fuel is injected from the reheating fuel nozzle. This refueling fuel contacts and mixes with the high-temperature burned gas from the catalyst and burns. The injected fuel is mixed somewhat with the air from the introduction hole, but basically causes a diffusion fire. In particular, in the case of liquid fuel, since it takes time until the evaporation proceeds after being injected, the fuel particles mix with the hot gas, evaporate and burn. It is said that the oxygen concentration in the burned gas is lowered by the amount consumed by the combustion with the catalyst, so that the generation of NOx due to the combustion of the reheating fuel is suppressed compared to the combustion in pure high-temperature air. However, in addition to the high-temperature burned gas being injected, it is not possible to exclude the high fuel concentration because the fuel is directly injected, so the fuel that can be replenished without increasing the amount of NOx so much The ratio is not so high. Also in Patent Document 2, the upper limit is set to 30%. On the other hand, in the technique of Patent Document 1, it has been demonstrated that 50% to 80% of the total fuel amount can be supplied from the main mixture injector without increasing NOx emission. Even if the increase in NOx is allowed, if excessive fuel is increased, smoke and particulate matter emissions will increase, which is not acceptable.

  In the first example of the axial staging described above, a part of the premixed gas injection pipe is inserted into the combustion chamber. Therefore, the premixer injection pipe is heated, and the air flowing through the premixer injection pipe is also preheated. This is advantageous in that when the fuel is a liquid fuel, the evaporation of the fuel spray is promoted and a more homogeneous air-fuel mixture can be formed, so that good combustion / discharge performance can be exhibited. On the other hand, in a combustor such as a regenerative cycle gas turbine where the air temperature is close to 600 ° C., the cooling effect from the inside of the premixing tube by air is reduced, and the outer surface of the premixed gas injection tube is exposed to a high temperature atmosphere. There is concern about oxidation problems. Further, since the premixed injection pipe is mounted on the combustor liner, it is necessary to open the combustor casing and take out the combustor liner when inspecting.

On the other hand, in the refueling fuel nozzle system as described above, the mixing of the injected fuel and the air flowing in from the air holes of the combustor liner is slow, and the fuel locally locally after being injected into the burned gas. The part which burns in an excessive state is inevitably formed. The larger the average fuel-air ratio, the easier it is to create a mixture with a large amount of local fuel, so the generation of NOx increases, and soot may be generated depending on the conditions. When the fuel is further increased, the fuel jet from the refueling nozzle itself holds the diffusion flame, and there is a problem that NOx increases rapidly. Therefore, the maximum fuel flow rate that can be repelled without sacrificing the discharge performance is about 10% of the total fuel flow rate at the rated load, which is considerably narrower than about 50 to 80% according to the first prior art. In addition, the refueling fuel nozzle system, in which fuel and air are not mixed before being injected into the burned gas in the combustion chamber, also takes time to mix with the burned gas, resulting in excessive local fuel at the combustor outlet. This leads to the generation of a high temperature spot, and in particular, in an annular combustor in which the combustor outlet immediately becomes a turbine inlet, there is a problem that the life of turbine parts such as a turbine nozzle is shortened. This problem can be alleviated if the distance from the fuel injection position to the turbine inlet is sufficient, but such measures are not allowed in aero engines where weight reduction is essential. The increase in the length of the combustor liner does not stop at an increase in the weight of the combustor liner, but an increase in the weight due to an increase in the length of related parts such as the rotating shaft of the engine and the casing, resulting in an increase in fuel consumption. In addition, maintenance costs increase due to increased manufacturing costs and component prices.
JP 2003-262336 A (see FIG. 1 and paragraph [0035]) JP 2003-3865 A

  In an axial staging type gas turbine combustor in which a plurality of combustion regions are arranged in the flow direction in a combustion chamber for the purpose of reducing emissions of NOx, unburned components (CO, hydrocarbons) and smoke in a wider load range. , The increase in the generation of NOx due to the combustion of the fuel supplied to the downstream combustion region is suppressed over a wider load range (or fuel-air ratio range), the uniformity of the combustor outlet gas temperature distribution is improved, and the combustor There is a problem to be solved in advancing the shortening. In addition, there is a problem to be solved in order to improve the durability and checkability of the air-fuel mixture injection pipe protruding into the combustion chamber.

  It is an object of the present invention to reduce emission of harmful components, particularly NOx, over a wider load range, to have excellent combustion stability, to have excellent uniformity in the temperature distribution of the combustor outlet gas, and to have a short spatial combustion load. A gas turbine combustor is provided.

  The present invention has been made to solve the above problems, and a gas turbine combustor according to the present invention is a burned gas generated in an upstream combustion region and flowing toward a downstream in a combustion chamber surrounded by a combustor liner. In a gas turbine combustor in which a fuel-air mixture is injected into a flow, an air-fuel mixture injector is attached to the wall of a combustor casing from the outside, and the air-fuel mixture injector includes a fuel injector, air swirling means, and an air-fuel mixture injection pipe An injection opening at the tip of the air-fuel mixture injection pipe is positioned in the vicinity of a liner opening disposed on the wall surface of the combustor liner, and the fuel-air mixture is passed through the liner opening from the injection opening. It is characterized by being injected so as to intersect the flow of burned gas.

  Since the burnt gas is high in temperature and contains a large amount of reaction active substances, even a very fuel-lean mixture can be reacted with the burnt gas by mixing it with the burned gas for a suitable time. Further, since NOx production is small as long as the fuel is lean, high combustion efficiency, that is, combustion with less CO and HC is possible with low NOx emission. Since the fuel-air mixture is injected so as to intersect the burned gas, mixing is easily performed. Further, since the air-fuel mixture injector is provided with means for swirling the air into which the fuel is mixed, that is, air swirling means, mixing of the fuel and air can be promoted, and the refueling nozzle that injects only the fuel Low NOx can be maintained over a wider fuel / air ratio range than with. In addition, the jet of the fuel-air mixture is swirled, which facilitates mixing with burned gas and burns in a short time, i.e. in a short distance (reactions that do not involve flames in the above ultra-lean conditions). Is complete, the uniformity of the combustor outlet gas temperature distribution is excellent. The fuel and air injected are mixed quickly and the fuel can be in a lean state, so that a self-supporting flame is not formed by the air-fuel mixture from the air-fuel mixture injection pipe. Since it reacts or burns for the first time, the generation of NOx and soot is less than the above-mentioned refueling nozzle that injects only fuel. The air-fuel mixture injector is mounted from the outside through a hole in the wall of the casing. Unlike the conventional premixing tube, the air-fuel mixture injection pipe is not fixed to the combustor liner, so the combustor liner is not taken out. Can be removed and easily inspected. Further, the air-fuel mixture injection pipe is durable because its tip is not exposed to the burned gas in the combustion chamber.

  In addition, the gas turbine combustor according to the present invention is characterized in that the air swirling means is an air swirler composed of a plurality of swirl vanes disposed inside or around the mixture injection pipe. By configuring the air swirler with a plurality of swirl vanes arranged inside or around the premixing tube, a compact air-fuel mixture injector can be realized.

  The gas turbine combustor according to the present invention is characterized in that the air swirling means is a tangential air inflow passage disposed on the side wall of the mixture injection pipe. If the side wall of the air-fuel mixture injection pipe is made thick and a tangential air inflow passage is provided on the side wall, air can flow into the air-fuel mixture injection pipe from this passage, and a swirling flow can be generated in the pipe. This form has the advantage that it can be manufactured at low cost and has high strength.

  In the gas turbine combustor according to the present invention, a cylindrical rotor having a tangential air inflow channel disposed on a side wall is coaxially disposed inside the mixture injection pipe, and the tangent is disposed on the side wall of the mixture injection pipe. An opening corresponding to the air inflow passage is disposed, and a vane extending into the tangential air inflow passage is disposed at an edge of the opening, and an effective opening area of the tangential air inflow passage by rotation of the rotor It is characterized in that it is changed. Alternatively, a slider having a vane extending in the tangential air inflow passage is disposed coaxially inside the jet pipe, and the tangential air inflow passage is moved by the axial movement of the jet slider. The effective opening area is changed.

  In both the rotor and slider forms, the flow rate of the air flowing into the air-fuel mixture injection pipe can be adjusted, and the fuel-air ratio of the air-fuel mixture can be controlled more appropriately. When the fuel flow rate is low, the air flow rate is throttled so that the reaction is more likely to occur when mixed with the burned gas of the mixture, while when the fuel flow rate is high, the mixture is mixed with the burned gas. The air flow rate can be increased so as not to become excessively high, and low NOx and complete combustion can be maintained in a wider fuel-air ratio range. Moreover, the uniformity of the combustor outlet temperature can be maintained.

  In the gas turbine combustor according to the present invention, a gap through which air flows is provided between the outer periphery of the tip of the mixture injection pipe and the edge of the opening of the combustor liner. By doing so, high-speed air can flow along the outer surface of the front end portion of the air-fuel mixture injection tube, and it is possible to prevent a flame from being formed in the air-fuel mixture injection tube. In addition, it is possible to prevent the tip of the air-fuel mixture injection pipe from being heated by radiation from a flame in the combustor liner or high-temperature burned gas. Further, by providing the gap, the displacement of the liner opening due to the thermal elongation of the combustor liner can be absorbed. Normally, the parts to be contacted are worn by mutual mechanical interference caused by aerodynamic force, heat, etc., but since the air-fuel mixture injection pipe according to the present invention is not in contact with the edge of the liner opening, the initial shape over a long period of time. Can be maintained.

  According to the present invention, in a gas turbine combustor in which a fuel-air mixture is injected into a burned gas flow that flows downstream from an upstream combustion region in a combustion chamber surrounded by a combustor liner, Since it is attached to the wall of the combustor casing from the outside, it can be easily removed, and the time and cost for maintenance and inspection of the air-fuel mixture injector can be reduced. In addition, since the positional relationship between the fuel injector and the air-fuel mixture injection pipe is maintained constant, there is an advantage that its performance is hardly affected by the tolerance of incorporation into the casing of the combustor liner. In addition, there is an advantage that the effective opening area of the gap is kept substantially constant even if the relative position of the combustor liner and the mixture injection pipe changes due to assembly or thermal elongation. Since the air-fuel mixture injection pipe is not exposed to the burned gas in the combustion chamber, it can withstand long-term use and reduce maintenance costs.

  In addition, the fuel-air mixture is not only injected so as to intersect the burned gas, but also the jet is swirled, so that mixing with the burned gas is promoted, and for a short time, that is, Combustion over a short distance (including the reaction that does not involve flames in the above ultra-lean conditions) completes the uniformity of the combustor outlet gas temperature distribution, and as a result, extends the life of the bin parts. There is an effect. Further, since the fuel is well mixed with air before being injected into the burned gas, the production of NOx due to the combustion of the injected fuel is effectively suppressed, and as a result, low NOx can be realized over a wide load range. There is.

  In addition, the gas turbine combustor according to the present invention has an air swirler configured of a plurality of swirl blades disposed inside or around the mixture injection pipe, or disposed on the side wall of the mixture injection pipe. Since it is a tangential air inflow channel provided, it is compact. Therefore, the present invention can also be applied when the gap between the combustor liner and the combustor casing is narrow. Moreover, it can be applied to existing combustors with relatively little additional work, and a combustor that meets emission standards can be realized at low cost.

  According to the air-fuel mixture injector using the rotor or slider capable of adjusting the swirling air flow rate according to the present invention, the flow rate of the air flowing into the air-fuel mixture injection pipe can be adjusted, and the fuel-air ratio of the air-fuel mixture can be adjusted more appropriately. Can be controlled. When the fuel flow is low, the air flow is throttled so that the reaction is more likely to occur when the mixture is mixed with burned gas, while when the fuel flow is high, the mixture is mixed with burned gas. In this case, it is possible to increase the air flow rate so as not to become excessively high temperature, maintain low NOx and complete combustion in a wider range of fuel air ratio, and maintain uniformity of the combustor outlet temperature.

  FIG. 1 is a longitudinal sectional view showing a first embodiment of a gas turbine combustor according to the present invention. The gas turbine combustor 1 shown in FIG. 1 has the same functions as the conventional parallel staging gas turbine combustor 3 shown in FIG. 11 and the conventional parallel staging gas turbine combustor 4 shown in FIG. Components and parts are denoted by the same reference numerals. This gas turbine combustor is widely used in small industrial gas turbines. A cylindrical combustor liner 51 is housed in a cylindrical combustor casing 52 and fuel injection is performed on a dome 53a of the combustion chamber 53. A burner 58 consisting of a vessel 54 and an air swirler 55 is mounted. The fuel from the fuel injector 54 is burned by the air from the air swirler 55 in the dome portion 53a of the combustion chamber, and burned gas is generated. For convenience, this combustion region will be referred to as the first combustion region 56. An air-fuel mixture injector 57 for injecting a fuel-air mixture into the burned gas from the first combustion region 56 is attached to the wall of the combustor casing 52 at a position downstream of the first combustion region 56. . In this example, two are arranged facing each other on two cross sections having different axial directions. In this example, the injection direction of the air-fuel mixture is substantially perpendicular to the flow of burned gas, but it may be preferable to incline upstream. These air-fuel mixture injectors 57 can be removed from the outside of the combustor casing 52. The front end 61 e of the mixture injection pipe 61 is positioned in the vicinity of the liner opening 51 c of the combustor liner 51, and the mixture injected from the mixture injection pipe opening outlet is the burned gas generated in the first combustion region 56. It mixes with the flow and reacts or burns depending on conditions such as the concentration of the mixture and the temperature after mixing. Since the reaction of the injected premixed gas or the generation of NOx due to combustion is negligible if the mixed gas is leaner than the flammability limit under normal temperature conditions, the amount of NOx emitted from the combustor is upstream. The amount of NOx produced by the burner 58 is almost determined. Therefore, if the burner 58 is a premixing system that emits less harmful components such as NOx, NOx emissions are significantly reduced.

  FIG. 2 is a longitudinal sectional view showing a second embodiment of the gas turbine combustor according to the present invention. FIG. 3 is a cross-sectional view. The gas turbine combustor 2 shown in FIG. 2 has the same functions as the conventional parallel staging gas turbine combustor 3 shown in FIG. 11 and the conventional parallel staging gas turbine combustor 4 shown in FIG. Components and parts are denoted by the same reference numerals. The gas turbine combustor is widely used in jet engines, that is, aviation gas turbines, and an annular combustion chamber 53 formed by an inner combustor liner 51a and an outer combustor liner 51b is a cylindrical combustor casing. 52. In the dome portion 53 a of the combustion chamber 53, dozens of burners 58 including a fuel injector 54 and an air swirler 55 are arranged in the circumferential direction. Combustion by these burners 58 is almost completed at the dome portion 53a. The burner 58 may be a premixing system that emits less harmful components such as NOx. For convenience, this combustion region will be referred to as the first combustion region 56. An air-fuel mixture injector 57 for injecting the fuel-air mixture to a position downstream of the first combustion region 56 is attached to the wall surface of the combustor casing 52. In this example, an air-fuel mixture injector 57 is disposed at the same circumferential position as the burner 58 disposed in the dome. However, as shown in another cross-sectional view of FIG. It can also be arranged between the burners. Further, as in the first embodiment, they can be arranged in two rows or more in the downstream direction. As the number of combustion regions in which fuel flow control is independently performed is increased, better discharge performance can be realized over a wider load range.

  FIG. 5A is an enlarged view of a longitudinal sectional view of the air-fuel mixture injector 57 attached to the combustor of the first embodiment of the present invention shown in FIG. 1 and the second embodiment shown in FIG. FIG. 5B is a cross-sectional view taken along line AA in FIG. The air-fuel mixture injection pipe 61 has a cylindrical shape, and a plurality of tangential air inflow passages 61b (six in the embodiment shown in the drawing) are arranged in the circumferential direction on the side wall 61a. The air flowing into the 61 forms a swirling flow by the cylindrical inner wall surface 61c. In this air flow, fuel is injected from a fuel injector 62 disposed on the central axis. This fuel is mixed with the swirling air and injected from the mixture injection pipe outlet 61d into the combustion chamber so as to intersect the flow of the burned gas 56a. The fuel may be liquid as well as gas. In the case of liquid fuel, a liquid atomizing nozzle is used as a fuel injector. A suitable gap 63 is formed between the outer periphery of the tip 61e of the mixture injection pipe and the edge of the combustor liner opening 51c, and air flows into the combustion chamber from the gap 63. This gap 63 is also effective in absorbing displacement due to thermal elongation. Further, there is an advantage that the effective opening area of the gap 63 is kept substantially constant even if the relative position of the combustor liner and the mixture injection pipe changes due to assembly or thermal elongation. The air-fuel mixture injector 57 is fixed to the wall surface of the combustor casing 52 with a bolt from the outside, and can be extracted outside. The air-fuel mixture injection pipe 61 may be a tapered circular pipe. Since the fuel injector is integrally attached to the air injection pipe, the positional relationship between the two is kept constant with high accuracy.

  FIG. 6A is a longitudinal sectional view showing the periphery of an air-fuel mixture injector 57 of a gas turbine combustor according to a third embodiment of the present invention, and FIG. 6B is an air-fuel mixture injection pipe in FIG. It is AA sectional drawing of 61. FIG. An air swirler 71 composed of a plurality of swirling blades 72 as an air swirling means is arranged inside the mixture injection pipe 61, and air flows from an opening 61f formed in a side wall of the mixture injection pipe 61, Air is swirled by the air swirler 71 and fuel is injected into the swirling air stream from the tip of the fuel injector 62. The air swirler 71 may be composed of a plurality of swirl vanes integrated with the fuel injector. In this figure, the fuel injector is a simple rod-like one, but an air atomization nozzle provided with a swirler in itself can also be used.

  FIG. 7 is a longitudinal sectional view showing the periphery of the mixture injection 57 of the gas turbine combustor according to the fourth embodiment of the present invention. Two air swirlers 71 a and 71 b composed of a plurality of swirl blades 72 are disposed inside the air-fuel mixture injection pipe 61 as air swirling means. This enhances the shear between the two coaxial swirling flows and further promotes the mixing of fuel and air. Further, if the turning directions of the two air swirlers 71a and 71b are reversed, the swirling is weakened in the central portion, the formation of negative pressure on the central axis is suppressed, and the backflow into the pipe can be eliminated. effective. It is desirable to eliminate the backflow because it may cause a fire in the gas mixture injection pipe and cause burning.

  FIG. 8 is a longitudinal sectional view showing the periphery of the air-fuel mixture injector 57 of the gas turbine combustor according to the fifth embodiment of the present invention. An air swirler 71 composed of a plurality of swirl blades 72 disposed on the outer periphery of the air-fuel mixture injection pipe is provided as air swirling means. According to this embodiment, there is an advantage that the cross-sectional area of the air swirler 71 can be made sufficiently larger than the cross-sectional area of the air-fuel mixture jet tube 61 and the amount of air flowing into the air swirler 71 can be increased.

  FIG. 9 is a longitudinal sectional view showing the periphery of the air-fuel mixture injector 57 of the gas turbine combustor according to the sixth embodiment of the present invention. A cylindrical rotor 81 having a tangential air inflow passage 81a disposed on the side wall is coaxial with the vane 82a extending into the tangential air inflow passage 81a and an air-fuel mixture injection pipe 61 having an opening 61f disposed on the side wall. The effective opening area of the tangential air inflow passage 81a is changed by the rotation of the rotor 81. The shaft 81c of the rotor 81 is driven by a servo motor or an air cylinder with a link mechanism, although not shown in the figure. The vanes and the open side walls are best illustrated, but may be flat.

  FIG. 10 is a longitudinal sectional view showing the periphery of the air-fuel mixture injector 57 of the gas turbine combustor according to the seventh embodiment of the present invention. A tangential air inflow passage 61b is disposed in the circumferential direction on the side wall 61a of the air-fuel mixture injection pipe 61, and a vane 82b extending into the tangential air inflow passage 61b is provided around the inside of the air-fuel mixture injection pipe 61. The arranged slider 83 is arranged coaxially, and the effective opening area of the tangential air inflow passage 61b is changed by the axial movement of the slider 83. The slurder is driven by an air cylinder and a hydraulic cylinder (not shown).

  The gas turbine combustor of the present invention is a mixture that achieves its function with low emission of harmful components over a wide range of fuel / air ratio, excellent combustion stability, and uniformity of combustor outlet gas temperature distribution. The air injector is compact and can be easily attached to and removed from the combustor casing from the outside, and can be easily applied to existing combustors, so it can be used as a jet engine or industrial gas turbine combustor over a wide operating range from low to high loads. Is available.

1 is a longitudinal sectional view showing a first embodiment of a gas turbine combustor according to the present invention. It is a longitudinal cross-sectional view which shows 2nd Example of the gas turbine combustor by this invention. It is AA sectional drawing of FIG. It is a cross-sectional view showing another gas mixture injection pipe position in the second embodiment of the gas turbine combustor according to the present invention. It is an enlarged view which shows the 2nd Example of the gas turbine combustor by this invention, and the air-fuel | gaseous mixture injector of 2nd Example, (a) is a longitudinal cross-sectional view, (b) is the BB sectional drawing. It is a figure which shows 3rd Example of the gas turbine combustor by this invention, (a) is an air-fuel | gaseous mixture injector and the longitudinal cross-sectional view of the circumference | surroundings, (b) is CC sectional drawing of an air-fuel | gaseous mixture injection pipe. FIG. 6 is a longitudinal and transverse sectional view showing an air-fuel mixture injector and its surroundings in a fourth embodiment of a gas turbine combustor according to the present invention. FIG. 7 is a longitudinal and transverse sectional view showing an air-fuel mixture injector and its surroundings in a fifth embodiment of a gas turbine combustor according to the present invention. It is a figure which shows the air-fuel | gaseous mixture injector and its periphery in 6th Example of the gas turbine combustor by this invention, (a) is a vertical-horizontal cross-sectional view, (b) is the DD sectional drawing. It is a figure which shows the air-fuel | gaseous mixture injector and its periphery in 7th Example of the gas turbine combustor by this invention, (a) is a vertical-horizontal cross-sectional view, (b) is the EE cross-sectional view. It is a longitudinal cross-sectional view which shows the gas turbine combustor which shows an example of the parallel staging provided with the conventional pilot burner and the main burner. 1 shows a gas turbine combustor including a premixed gas injection pipe extending into a combustion chamber, which is an example of a conventional axial staging gas turbine combustor, (a) is a longitudinal sectional view thereof, and (b) is an FF thereof. It is an arrow view.

Explanation of symbols

1, 2, 3, 4, 5 Gas turbine combustor 11 Pilot burner 11a Pilot combustion region 12 Main burner 12a Main combustion region 13 Burned gas lump 14 Main premixed gas injection pipe 15 Main premixed gas
51 Combustor liner 51a Inner combustor liner 51b Outer combustor liner 51c Combustor liner opening 52 Combustor casing 53 Combustion chamber, annular combustion chamber 53a Dome portion 54 Fuel injector 55 Air swirler 56 First combustion region 56a Burned gas 57 Mixture injector 58 Burner 61 Mixture injection pipe 61a Side wall 61b Tangential air inlet passage 61c Cylindrical inner wall surface 61d Mixture injection pipe outlet 61e End of mixture injection pipe 61f Opening 62 Fuel injector 63 Clearance 71, 71a, 71b Air Swivel 72 Swivel blade 81 Rotor 81a Tangential air inflow passage 81c Rotor shaft 82a, 82b Vane 83 Slider

Claims (6)

  In a gas turbine combustor in which a fuel-air mixture is injected into a burned gas stream generated in an upstream combustion region and flowing downstream in a combustion chamber surrounded by a combustor liner, the mixture is injected onto the wall of the combustor casing The fuel injector is composed of a fuel injector, an air swirling means, and a fuel injection pipe, and an injection opening at the tip of the fuel injection pipe is disposed on the wall surface of the combustor liner. The gas turbine combustor is located near the liner opening, and the fuel / air mixture is injected from the injection opening through the liner opening so as to intersect the flow of the burned gas.   2. The gas turbine combustor according to claim 1, wherein the air swirling unit is an air swirler including a plurality of swirl blades disposed inside or around the air-fuel mixture injection pipe.   The gas turbine combustor according to claim 1, wherein the air swirling means is a tangential air inflow passage disposed on a side wall of the mixture injection pipe.   A cylindrical rotor having a tangential air inflow passage disposed on a side wall is coaxially disposed inside the mixture injection pipe, and an opening corresponding to the tangential air inflow passage is provided on the side wall of the mixture injection pipe. A vane extending into the tangential air inflow channel is disposed at the edge of the opening, and the effective opening area of the tangential air inflow channel is changed by rotation of the rotor. The gas turbine combustor according to claim 1 or 2.   A slider having a vane extending around the tangential air inflow passage is disposed coaxially inside the tangential air inflow passage, and the tangential air inflow passage is moved axially by the slider. The gas turbine combustor according to claim 3, wherein an effective opening area of the gas turbine is changed.   The gas turbine according to any one of claims 1 to 5, wherein a gap through which air flows is provided between an outer periphery of a tip of the mixture injection pipe and an edge of the combustor liner opening. Combustor.

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