Abstract: There is provided a combustor to burn fuel, comprising a bypass passage connected to one side of the combustor to supply air into the combustor; and an annular passage provided around the combustor and connected to the bypass passage, wherein air supplied through the bypass passage passes in the annular passage in the circumferential direction, and is uniformly supplied into the combustor in the circumferential direction thereof through an opening which connects the combustor and the annular passage. Accordingly, compressed air passing through the bypass passage can be supplied uniformly into a tail portion of the combustor, and unevenness of temperature distribution in a cross section of the combustor tail portion can be reduced.

Abstract: A gas turbine combustor includes a side wall, for defining a combustion volume, having upstream and downstream ends, a pilot nozzle, disposed adjacent the upstream end of the side wall, for discharging a pilot fuel to form a diffusion flame in the combustion volume, and a plurality of main nozzles, provided around the pilot nozzles, for discharging a fuel-air mixture to form premixed flames in the combustion volume. Film air is supplied into the combustion volume downstream of the main nozzles along the inner surface of the side wall to reduce the fuel-air ratio in a region adjacent the inner surface of the side wall and to restrain a combustion-driven oscillation in the combustion volume.

Abstract: A steam-cooled combustor for a gas turbine has cooling steam passages, the steam flowing in opposite axial directions in adjacent channels.

Abstract: A gas turbine combustor improves the fuel distribution from a main fuel nozzle, suppressing fluctuations of internal pressure and elevation of inner tube metal temperature, and enhancing the combustion stability and durability of the combustor. The gas turbine combustor is a multi-nozzle type premixing combustor with a nozzle outer tube (7) for forming and injecting a premixed gas of main fuel and combustion air divided and disposed in plural sections around a cone (4) for forming a diffusion flame by reaction between pilot fuel and combustion air disposed in a center of a section of a combustor inner tube (1). Nozzle holes (5a) of a main fuel nozzle (5) are formed in three positions at equal intervals on the nozzle main body wall, and one of them is disposed at the outer periphery of the combustor inner tube (1) on a diametral line linking between the center of the combustor inner tube (1) and the center of the main fuel nozzle (5), whereby the fuel distribution to the outer periphery is decreased.

Abstract: A dual fuel nozzle is provided with two different size injection holes. The first injection holes have larger diameters and are used only for injecting gaseous fuel into a combustion chamber. On the other hand, the second injection nozzles have smaller diameters and are used for injecting either gaseous fuel or liquid fuel as required. When gaseous fuel is used, if the fuel injection amount is large or medium, both of the first and the second injection holes or first injection holes only are used for injecting gaseous fuel depending upon the required fuel injection amount. When the fuel injection amount is low, only the second injection hole is used for injecting gaseous fuel. Therefore, the pressure drop across the fuel nozzle can be kept at sufficiently high level even when the fuel injection amount is low, and thereby combustion vibration is suppressed. Further, when liquid fuel is used, a premixed fuel and steam mixture is injected from the second injection holes.

Abstract: For the purpose of reduced NOx gas emission, a gas turbine engine comprises a cylinder having a combustion region inside of the cylinder; a resonator having a cavity and provided around the surface of the cylinder and sound absorption holes formed on the cylinder and having opening ends on the cylinder.

Abstract: A combustor includes a burner and a combustion chamber including a heat chamber to which fuel is supplied from the burner. The burner includes a nozzle having a fuel discharge outlet from which the fuel is discharged into the combustion chamber; and the nozzle includes a plurality of discharge openings around the fuel discharge outlet from which cooling water is discharged toward inside surfaces of the heat chamber. The plurality of discharge openings may be disposed so that the directions of the cooling water discharged from the discharge openings differ in the radial direction.

Abstract: A gas turbine system and a combined plant including the gas turbine system provides a higher effect in realizing a high plant efficiency and reduction of NOx generation. The gas turbine system includes a compressor (1) for compressing combustion air, a combustor (2) for burning fuel with the combustion air, and a gas turbine (3) driven by high temperature gas generated at the combustor (2). A portion of the exhaust gas discharged from the gas turbine (3) is recirculated back into the combustor (2). A combined plant can also include the gas turbine system.

Abstract: Gas turbine system is constructed such that no fuel gas compressor is used and a turbine is operated at low temperature so that a life of the system is elongated and the safety is enhanced. Air compressed at a compressor (11) of about 200° C. enters a heat exchanger (12) to be heated by combustion gas to about 760 to 900° C. to enter the turbine (13) and to work to rotate a generator (15). Exhaust air of the turbine (13) of which temperature is lowered to about 500 to 750° C. is supplied into a combustor (14) for fuel combustion to generate high temperature combustion gas of about 800 to 950° C. This combustion gas enters the heat exchanger (12) to heat the air from the compressor (11). The air is heated by the high temperature combustion gas with no fuel gas compressor being used and the turbine is operated by the lower temperature air as compared with a conventional case. Hence, the system is made less expensive, the life is elongated and the safety is enhanced.

Abstract: This invention relates to a fuel discharge member which can reduce the amount of NOx exhaust. The fuel discharge member is fixed on a fuel supply conduit, and comprises: a main body having an internal space which communicates with a fuel passage in the fuel supply conduit, fuel discharge outlets which communicate with the internal space, and a trailing edge. The thickness of the trailing edge is no more than 5 mm, or a flow passage block ratio of the fuel discharge member is no more than 10% with respect to the cross-sectional area of the air flow passage in which the fuel discharge member is to be placed. Alternatively, the main body is a flat tube.

Abstract: This invention relates to a combustor which can simultaneously reduce an amount of NOx exhaust and combustion oscillation. The combustor comprises an internal cylinder which accommodates a premixing nozzle, and an external cylinder which accommodates the internal cylinder and includes an air flow passage which supplies air from a compressor to the premixing nozzle. The air flow passage is provided with a punched metal plate near the maximum velocity fluctuation position wherein the velocity fluctuation of the air flow is increased to the maximum.

Abstract: In a central portion of inner tube 28 of combustor 20, pilot fuel nozzle 22 and pilot cone 33 are arranged and main fuel nozzles 21 and main swirlers 32 therearound. Air intake portion (X-1) is provided with rectifier tube 11 for making air intake uniform. In air intake portion (X-2), air holes of appropriate number of pieces are provided in circumferential wall of the inner tube 28. In main swirler portion (X-3) and pilot cone portion (X-4), bolt joint of the main swirlers 32 is employed and optimized welded structure having less influence of thermal stress of the pilot swirler 33 is employed, respectively. Tail tube cooling portion (X-5) is provided with cooling structure having less influence of thermal stress to cool flange 71 portion of tail tube 24 uniformly. By the improvements in the portions (X-1) to (X-5), obstacles in attaining higher temperature in the combustor 20 is dissolved and combustor performance is enhanced.

Abstract: To present a gas turbine combustor capable of improving the fuel distribution from the main fuel nozzle, suppressing fluctuations of internal pressure and elevation of inner tube metal temperature, and enhancing the combustion stability and durability of the combustor.

Abstract: To present a cooling structure of combustor tail tube capable of avoiding formation of cracks in the tail tube by lessening thermal stress and preventing thermal deformation, and extending the service life, the invention provides a cooling structure of combustor tail tube forming a multiplicity of cooling jackets (5) extending in the longitudinal direction of tail tube of a gas turbine combustor along the entire circumference of the tail tube wall, in which passage sectional area of the cooling jackets (5) is varied depending on the metal temperature of parts of the tail tube (4), for example, the passage sectional area of the cooling jackets (5) formed at the rotor side wall and the mutually opposite side walls of the adjacent tail tube is formed larger than the passage sectional area of the cooling jackets (5) formed at the casing side wall.

Abstract: A nozzle cap (10) is disposed downstream of a nozzle body (1) of a combustor for a gas turbine, an inner surface part (12) of which is of a conical shape diverging downstream to define a fuel-jet guide (17) for guiding fuel jet ejected from one or more nozzle holes (3) provided at the center of a downstream end surface of the nozzle body. Fuel ejected from the one or more nozzle holes smoothly runs along the fuel-jet guide without remaining there to join with a swirl stream (S) in a swirl path (9), and to burn without generating smoke. Air introduced into a first auxiliary air path (6) defined between the nozzle body and a partition (5) at a position upstream thereof passes through a second auxiliary air path (16) defined between a downstream end surface (2) of the nozzle body (1) and an upstream end surface (13) of the nozzle cap and reaches an entrance (19) of the fuel-jet guide.

Abstract: A combustor of a gas turbine includes a combustion tube acting as a combustion chamber. In the combustion tube, a cylindrical heat insulating member is disposed and forms a wall of the combustion chamber. Numerous cooling air passages are formed in the heat insulating member and extending in the axial direction between cooling air inlet disposed at one end of the heat insulating member and cooling air outlet disposed at the other end of the heat insulating member. The heat insulating member is attached to the inner surface of the combustion tube at its cooling air inlet side end and a seal ring is disposed around the outer circumference of the heat insulating member at a portion between the cooling air inlet side end and the cooling air outlet side end. The seal ring is made of heat resistant material and prevents cooling air flowing through the annular space between the inner surface of the combustion tube and the outer surface of the heat insulating member.

Abstract: A pre-mixture forming swirler in a gas turbine pre-mixed flame type low NOx combustor is improved so as to accelerate mixing of fuel and air and to prevent the occurrence of flame stagnation and burning of components. In particular, a three-dimensional swirler is constructed such that each swirler vane (101a) is twisted from a hub side thereof to a tip side so that a fitting angle (&bgr;) of the tip side relative to the center axis (C) of the fuel nozzle (102) is larger than the angle (&agr;) of the hub side. Thereby, while the angle (&agr;) of the hub side is set smaller so that flame stagnation and burning of components resulted therefrom may be prevented from occurring, the angle (&bgr;) of the tip side may be selected so that the shearing flow necessary for appropriate mixing of fuel (F) and air (A) is obtained. Thus, favorable pre-mixing is achieved, life deterioration due to the burning etc. is prevented and combustion efficiency is enhanced.

Abstract: A gas turbine combustor, in which plural pre-mixers that inject fuel into swirling air passages are arranged to surround a pilot burner, and a pilot flame, guided by a pilot cone in the shape of a flaring pipe and provided at the rear end of the pilot burner, is mixed with a pre-mixture blown out from the pre-mixers to obtain a combustion gas, comprising flame-stabilizing means. The flame-stabilizing means lower the disturbance in a region where the pre-mixture and the pilot flame are mixed or stabilize the pilot flame, so that the flame generated by igniting the pre-mixture with the pilot flame is stabilized. By stabilizing the flame, combustion with a leaner air-fuel ratio is possible, and thereby the amount of NOx can be decreased.

Abstract: A gas turbine is provided with combustors having cooling passages formed in the wall of the combustors. The walls of the combustors are cooled by cooling fluid flowing through the cooling passages. Steam generated by a waste heat recovery boiler is supplied to the cooling passages as cooling fluid during the normal operation of the gas turbine. During start up and shut down operation of the gas turbine, pressurized air from the gas turbine compressor is supplied to the cooling passage as cooling fluid. Since pressurized air from the gas turbine compressor is used for cooling fluid for the combustors during start up and shut down operations, a separate auxiliary boiler is not required for supplying cooling steam to the combustor during start up and shut down operation.

Abstract: In a central portion of inner tube 28 of combustor 20, pilot fuel nozzle 22 and pilot cone 33 are arranged and main fuel nozzles 21 and main swirlers 32 therearound. Air intake portion (X-1) is provided with rectifier tube 11 for making air intake uniform. In air intake portion (X-2), air holes of appropriate number of pieces are provided in circumferential wall of the inner tube 28. In main swirler portion (X-3) and pilot cone portion (X-4), bolt joint of the main swirlers 32 is employed and optimized welded structure having less influence of thermal stress of the pilot swirler 33 is employed, respectively. Tail tube cooling portion (X-5) is provided with cooling structure having less influence of thermal stress to cool flange 71 portion of tail tube 24 uniformly. By the improvements in the portions (X-1) to (X-5), obstacles in attaining higher temperature in the combustor 20 is dissolved and combustor performance is enhanced.