Abstract: The present invention includes a flow guide (17) that is disposed in a space (15A) formed in a casing, on an outlet side of a diffuser (14), the flow guide including: a first guide surface (17a) that is disposed on a rotor side provided to a compressor and a gas turbine, and that delays turning of a flow direction of a compressed gas which has passed through the diffuser (14); and a second guide surface (17b) that is disposed outside the first guide surface (17a) and that turns the flow direction of the compressed gas which has passed through the diffuser (14).

Abstract: A gas turbine engine, including: a diffuser case defining an inner shroud and an outer shroud; and a combustor housed within the diffuser case between the inner shroud and the outer shroud, the combustor including: a shell; a forward dome attached to the shell at a forward end of the combustor; and a deflector attached to the forward dome and extending away from the forward dome.

Abstract: A thermally responsive flow meter may comprise a coil and a plate coupled to the coil. The plate may define a first airflow aperture. The plate may translate in a circumferential direction in response to a thermal expansion of the coil. The thermally responsive flow meter may regulate the flow of air through a second airflow aperture.

Abstract: The present application provides a low carbon martensitic high temperature strength steel and a preparation method thereof, wherein the chemical composition of the low carbon martensitic high temperature strength steel are: C: 0.10-0.25 wt %, Cr: 10.0-13.0 wt %, Ni: 2.0-3.2 wt %, Mo: 1.50-2.50 wt %, Si?0.60 wt %, Mn?0.60 wt %, W: 0.4-0.8 wt %, V: 0.1-0.5 wt %, Co: 0.3-0.6 wt %, Al: 0.3-1.0 wt %, Nb: 0.01-0.2 wt %, and a balance of Fe. The high temperature strength steel of the present application achieves high strength at high temperature by simultaneously precipitating both nano-coherent carbides and intermetallic compounds. It has an excellent toughness, and can be used for certain structural parts under special working conditions, such as aero-engines to increase its service life and service temperature.

Abstract: A heat engine including a wall assembly is generally provided. The wall assembly includes a plurality of radial walls coupled together via a connecting member. The radial wall defines a flow opening therethrough. A flow cavity is defined between the plurality of radial walls and the connecting member.

Abstract: The can combustion chamber includes a casing housing a plurality of cans. Each can includes a wall and a perforated cooling liner around the wall. Cooling liners of adjacent cans have staggered perforations.

Abstract: A gas turbine combustor and a gas turbine; wherein inclined surfaces are provided on inner surfaces of side walls neighboring in a circumferential direction at downstream end portions of transition pieces of combustors, the inclined surfaces being configured to increase a passage area of the transition pieces, a ratio (S/P) is from 0 to 0.2, where (P) is a pitch dimension of first stage vanes, and (S) is a circumferential dimension from an intermediate point between neighboring transition pieces to an upstream end of a first stage vane closest in the circumferential direction; and a ratio (L/P) is from 0.3 to 0.55, where (P) is the pitch dimension, and (L) is an axial dimension from a downstream end of the transition piece to the upstream end of the first stage vane.

Abstract: A crossfire tube to pass a flame from a combustor chamber of a first combustor to a combustor chamber of a second combustor adjacent to the first combustor is provided. The crossfire tube includes a first insertion pipe configured to connect an inner liner and an outer liner of the first combustor, the inner liner defining the combustion chamber and the outer liner surrounding the inner liner, a second insertion pipe configured to connect an inner liner and an outer liner of a liner of the second combustor, and a connection pipe disposed between the first combustor and the second combustor and connected to the first insertion pipe and the second insertion pipe at respective ends thereof so that the combustion chamber of the first combustor communicates with the combustion chamber of the second combustor via the connection pipe.

Abstract: A system for retaining a cross fire tube in a multi-combustor gas turbine engine is disclosed. The system comprises a flow sleeve having a generally annular body, and a flange at a forward end thereof and having one or more recessed portions. A cross fire tube extends through one or more openings in the flow sleeve and is secured in place by a retention clip. The retention clip includes a plurality of fingers which engage the cross fire tube and a mounting plate engaging the one or more recessed portions of the flow sleeve flange so as to create a clip engagement having a lower profile than prior art configurations.

Abstract: A gas turbine engine and combustor assembly is generally provided. The gas turbine engine may include an outer casing while the combustor assembly may include a liner and a damper assembly. The liner may at least partially define a combustion chamber extending between an aft end and a forward end generally along an axial direction within the outer casing. The liner may include an inner surface facing the combustion chamber and an outer surface facing away from the combustion chamber. The damper assembly may extend between the outer casing and the outer surface of the liner. The damper assembly may include a selectively separable support and damper spring. The damper spring may be disposed between the support and the liner.

Abstract: A transition piece can include: an inner transition piece including an inlet and an outlet; an outer transition piece surrounding the inner transition piece with a flow passage; an outlet fin-pin flow guide disposed on the inner transition piece and located closer to the outlet than the inlet; a first bottom fin disposed at a bottom portion of the inner transition piece; and a second bottom fin disposed at the bottom portion of the inner transition piece, wherein the first bottom fin and the second bottom fin are arranged to be inclined to each other at an acute angle.

Abstract: A transition piece support structure for a gas turbine combustor, and a method of installing same, reliably prevent leakage at the flange of a lower-side combustor, which is greatly influenced by gravity. The structure supports a rear end portion of a transition piece when fixed to a turbine end and includes a flange provided at a rear end of the transition piece, to be coupled to the end of the turbine, the flange having a shape to fit a periphery of a turbine inlet; a support bracket integrated with an upper surface of a flow sleeve surrounding an outer surface of the transition piece, to face the end of the turbine coupled to the flange; and a connection piece fixed to the end of the turbine and configured to be coupled to the support bracket in a hinged manner allowing the flange to pivotally approach the turbine inlet.

Abstract: A system may include a transition piece, coupled to a support of the system, to receive combustion products from a combustion chamber. The system may also include a turbine nozzle, coupled to a support of the system, to receive combustion products from the transition piece. Additionally, a web plate disposed at a radial position about a turbine axis between the transition piece and the turbine nozzle may form a first seal between the web plate and the transition piece and form a second seal between the web plate and the turbine nozzle. In addition, the web plate may extend in a circumferential direction about the turbine axis and couple to a support of the system. Further, the web plate may include an inner surface, an outer surface, and an arm extending in a radial direction between the inner surface and the outer surface.

Abstract: An aft frame for a duct of a combustor includes a rail or radial projection that extends circumferentially around the aft frame and that defines an outer surface of the aft frame. A preformed cover plate having an inner surface is attached to the outer surface of the aft frame. A plurality of micro-cooling channels is formed within at least one of the inner surface of the preformed cover plate and the outer surface of the aft frame. The preformed cover plate extends across the plurality of micro-cooling channels.

Abstract: The invention relates to a gas turbine assembly which substantially includes at least one compressor, at least one first burner, at least one second burner that is connected downstream of the first burner, and at least one turbine that is connected downstream of the second burner. At least the first and second burner form a component of a tubular or quasi-tubular combustion chamber element in the flow direction of the combustion path of the burners. The combustion chamber element being closed or quasi-closed and extending between the compressor and the turbine. The combustion chamber elements are arranged around the rotor of the gas turbine assembly in the shape of a ring.

Abstract: A heat shield for a gas turbine engine includes a radial heat shield flange that extends in a circumferential direction and forms a ring. A plurality of bosses extend from a first axial side of the radial heat shield flange. There is a plurality of guide pins. One of the plurality of guide pins extends from a corresponding one of the plurality of bosses.

Abstract: A flow mixing lobe for an exhaust diffuser includes a first flange member having a first leading end, a first trailing end, and an intermediate portion extending therebetween. A second flange member includes a second leading end, a second trailing end, and an intermediate section extending therebetween. A first leg portion includes a first end extending from the first flange member, and a second end. A second leg portion has a first end portion extending from the second flange member, and a second end portion. A wing member is arranged between the first and second leg portions at respective ones of the second end and second end portions. The wing member includes a flow conditioning surface having a non-linear profile extending between the second end and the second end portion.

Abstract: A gas turbine combustor is disclosed, comprising: a combustor liner; a combustor casing, at least partly housing the combustor liner, and a liner support arrangement. The liner support arrangement comprises individual support elements located between the combustor liner and the combustor casing. Each support element comprises a liner support member fixed to the combustor liner and a casing support member fastened to the combustor casing. Each casing support member comprises a casing stop seat fixed on the combustor casing and a replaceable casing stop, detachably coupled to the casing stop seat.

Abstract: A sealing arrangement for sealing between a first stage nozzle and a plurality of aft frames includes a first inner seal and a second inner seal which are circumferentially oriented and circumferentially aligned. A side seal is radially disposed between the first inner seal and the second inner seal. The side seal includes a first portion that is axially offset from the first inner seal and the second inner seal and a second portion abutting the first inner seal and the second inner seal. Also disclosed is an aft frame having a forward face and an aft face. The aft frame includes at least one side seal slot that extends along a side portion. A first portion of the side seal slot is axially offset from the aft face. A second portion of the side seal slot is axially and radially offset from the first portion.

Abstract: A combustor assembly for use in a gas turbine engine includes a combustor liner that defines a combustion chamber and includes an axial combustion portion and a curved transition portion. The combustion liner also includes an inner surface and an outer surface and a first plurality of cooling channels defined between the inner and outer surfaces. The combustor assembly also includes a sleeve substantially circumscribing the combustor liner such that an annular cavity is defined between the combustor liner and the sleeve. The sleeve includes a second plurality of cooling channels defined therethrough that are configured to channel a fluid against the combustor liner outer surface.

Abstract: The present disclosure is directed to a segmented annular combustion system including a first panel fuel injector including a premix air plenum, a fuel plenum, and a plurality of first side premixing channels, where each first side premixing channel is in fluid communication with the premix air plenum, the fuel plenum, and a respective first side injection aperture of a plurality of first side injection apertures. A second panel fuel injector is circumferentially spaced from the first panel fuel injector and includes a premix air plenum, a fuel plenum, and a plurality of second side premixing channels where each second side premixing channel is in fluid communication with the premix air plenum, the fuel plenum, and a respective second side injection aperture of a plurality of second side injection apertures. A fuel nozzle is disposed circumferentially between the first panel fuel injection and the second panel fuel injector.

Abstract: In a gas turbine in which a seal member seals a gap between a transition piece and a nozzle end wall in a turbine first stage, the transition piece and the nozzle end wall has a seal groove. The seal member includes a hook portion that slides in the turbine radial direction with respect to the flange and a seal plate portion inserted in the groove. The groove and the portion are configured to include a surface contact region in which a surface of the groove and the portion are in surface contact with each other, a non-contact region disposed on a side closer to the transition piece than the region, and a hole provided at the portion so as to face the surface in the groove across a gap in the region.

Abstract: The present disclosure is directed to an annular combustion system. The annular combustion system includes an inner liner and an outer liner that define therebetween an annulus that circumscribes a centerline of the combustion system. The annulus includes a plurality of primary combustion zones defined at an upstream end thereof and further defines a plurality of secondary combustion zones downstream of the primary combustion zones. The annular combustion system further includes a plurality of fuel nozzles where at least one fuel nozzle discharges a combustible mixture into a respective primary combustion zone of the plurality of primary combustion zones. A plurality of panel fuel injectors is disposed between adjacent fuel nozzles. The plurality of panel fuel injectors extends in an axially downstream direction so as to separate adjacent primary combustion zones. Each panel fuel injector discharges a combustible mixture into at least one secondary combustion zone.

Abstract: A gas turbine engine includes: a plurality of combustors disposed so as to incline radially outward from a turbine side toward a compressor side; and a diffuser inner tube and outer tube forming a diffuser as an upstream portion of a path that introduces a compressed gas from the compressor to the combustors. A transition duct portion of each combustor has such a shape that a circumferential dimension thereof gradually decreases from the turbine side to the compressor side so that a circumferential gap is formed between the transition duct portions. Downstream-side portions of the diffuser inner tube and outer tube each have a shape gradually increasing in diameter toward the downstream side. A turbine-side end of the circumferential gap at an inner diameter side of the transition duct portion is positioned radially inward of an imaginary extension conical surface continuous from the diffuser inner tube.

Abstract: A combustor including a combustor main body having a transition piece that defines a flow channel therein, and a combustor basket inserted in the transition piece from an upstream side of the flow channel that defines a gap through which a film air is sent with an inner peripheral surface of the transition piece; a connecting pipe disposed upstream of an outlet of the gap that connects to the combustor main body from an outer peripheral side and communicates with the flow channel via a connection hole; and a flow guide disposed at an identical position to the outlet of the gap on a downstream side of a connecting portion of the connecting pipe and the combustor main body that guides a compressed air introduced from outside the connecting pipe so that a flow rate distribution is made uniform in a circumferential direction of the combustor main body.

Abstract: The present disclosure is directed to the operation and turndown of a segmented annular combustion system. The method includes injecting, via a fuel nozzle, a combustible mixture into a primary combustion zone between an adjacent pair of integrated combustor nozzles and burning the combustible mixture. The method further includes flowing air and injecting fuel into a premixing channel defined within a first integrated combustor nozzle to produce a second combustible mixture. The second combustible mixture is injected into a secondary combustion zone where it is combusted. The flow of combustion gases is accelerated, via turbine nozzles of the integrated combustor nozzles, toward turbine blades of a downstream turbine section. The method permits turndown of the combustion system by reducing or shutting off fuel to various components of the combustion system.

Abstract: A seal structure includes: a first member and a second member facing a combustion gas flow passage; a third member on an outer side of the combustion gas flow passage; a heat-resistant coating on at least one of a first end face and a second end face, both of the first end face and the second end face being closer to the combustion gas flow passage; and a contact part in each of the first end face and the second end face, further on the outer side of the combustion gas flow passage than the heat-resistant coating. The contact part is configured to restrict relative movement of the first member and the second member by directly or indirectly coming into contact with the first member and the second member in a state where a clearance is left between the heat-resistant coating and the end face facing the heat-resistant coating.

Abstract: A burner for a combustion chamber of a gas turbine with a mixing and injection device, which includes a limiting wall that defines a gas-flow channel and at least two streamlined bodies. Each streamlined body extends in a first transverse direction into the gas-flow channel, and has two lateral surfaces that are arranged essentially parallel to the main-flow direction. The lateral surfaces are joined to one another at their upstream and downstream sides to form leading and trailing edges of the body, respectively. At least one of the streamlined bodies includes a mixing structure and at least one fuel nozzle at its trailing edge for introducing at least one fuel essentially parallel to the main-flow direction into the flow channel. At least two of the streamlined bodies have different lengths along the first transverse direction such that they may be used for a can combustor.

Abstract: The present invention provides a multi-can type gas turbine combustor including a plurality of combustors that mix and burn fuel and the air, the combustors being connected by a crossfire tube assembly. The gas turbine cools the crossfire tube assembly without lowering the temperature of a combustion exhaust gas passing through the crossfire tube assembly and prevents thermal deformation and fire damage of the crossfire tube assembly. In a gas turbine according to the present invention, a guide ring that guides a current of the air is provided in a position opposed to air holes. One side end portion of an annular space configured between the guide ring and a crossfire tube assembly is opened to a space on the inside of the crossfire tube assembly. The other end portion is a closed end connected to a partition wall configuring the crossfire tube assembly. The length of an annular space between the air holes and the closed end is set to three times or more as large as the diameter of the air holes.

Abstract: A plurality of gas turbine combustors having a cross fire tube assembly that connects adjacent combustors. The combustors include combustion chambers having annular combustion air passages on outer peripheries thereof. The cross fire tube assembly has a dual pipe configuration including an inner tube that connects the combustion chambers of the adjacent combustors and an outer tube that covers therein the inner tube and connects the combustion air passages of the adjacent combustors. The cross fire tube assembly further has openings disposed between the inner tube and the outer tube of outer peripheral partition walls of the combustion air passages that are connected with the outer tube of the cross fire tube assembly centering on the inner tube. The openings allow combustion air to flow in areas upstream and downstream of the inner tube with respect to a flow of the combustion air flowing through the combustion air passages.

Abstract: The invention refers to a transition piece of a combustor of a gas turbine including an impingement cooling zone, a sequential disposed liner having at least one cooling arrangement and a closing plate with respect to the sequential disposed liner. The sequential disposed liner has a cooling channel structure. The cooling channel structure forms a closed loop cooling scheme or a quasi-closed loop cooling scheme. The cooling channel structure is operatively connected to a cooling medium to cool at least one part of the sequential disposed liner.

Abstract: A combustor cap module is provided with a retention system to facilitate assembly and disassembly. The combustor cap module further includes a cap face assembly having a cooling plate; a cylindrical sleeve including a connecting surface for attaching the cap face assembly to the retention assembly; and a coupling member mounted in a downstream fuel nozzle opening in the cooling plate. The retention system includes a support plate having an inner panel that defines an upstream fuel nozzle opening. The coupling member extends through the upstream fuel nozzle opening, such that its upstream end extends upstream of the support plate. A retaining ring at least partially encircles the upstream end of the coupling member and is engaged by a spring plate that is removably secured to the support plate at multiple locations. A method for assembling a combustor cap module is also provided.

Abstract: A combustor is capable of ignition and flame propagation at low fuel concentrations for gas or liquid fuel. Combustors are disposed annularly along an outer peripheral portion of a casing of a turbine. A combustion chamber burns fuel and air to generate a combustion gas. A diffusion burner is disposed upstream of the combustion chamber; and a plurality of premix burners are disposed around the diffusion burner. Cross fire tubes provide communication between combustion chambers of combustors adjacent to each other. A cross fire tube connected to a combustor adjacent to a first side in the circumferential direction of the casing is disposed so as to have a central axis passing over a premix burner as viewed from the combustion chamber and another cross fire tube connected to the combustor adjacent to a second side is disposed so as to have a central axis passing between two premix burners.

Abstract: A burner for a combustion chamber of a gas turbine with a mixing and injection device, which includes a limiting wall that defines a gas-flow channel and at least two streamlined bodies. Each streamlined body extends in a first transverse direction into the gas-flow channel, and has two lateral surfaces that are arranged essentially parallel to the main-flow direction. The lateral surfaces are joined to one another at their upstream and downstream sides to form leading and trailing edges of the body, respectively. At least one of the streamlined bodies includes a mixing structure and at least one fuel nozzle at its trailing edge for introducing at least one fuel essentially parallel to the main-flow direction into the flow channel. At least two of the streamlined bodies have different lengths along the first transverse direction such that they may be used for a can combustor.

Abstract: A gas turbine engine includes a vane and a combustor housing that are supported relative to an engine static structure. A retaining assembly clamps the combustor housing and the vane to one another in an axial direction. A circumferential load transfer assembly circumferentially affixes the vane relative to the engine static structure. The retaining assembly is secured to the circumferential load transfer assembly.

Abstract: A turbomachine includes a plurality of transition ducts and a support ring assembly. The outlet of a transition duct includes an inner flange and an outer flange. The turbomachine includes bore holes defined in the inner flange and outer flange, mating bore holes defined in the support ring assembly, and mechanical fasteners connecting the inner flange and the outer flange to the support ring assembly. A first one of the bore holes or mating bore holes has a first maximum radial gap and a first maximum tangential gap relative to an associated mechanical fastener. A second one of the bore holes or mating bore holes has a second maximum radial gap and a second maximum tangential gap relative to an associated mechanical fastener. The second maximum radial gap is greater than the first maximum radial gap or the second maximum tangential gap is greater than the first maximum tangential gap.

Abstract: A turbomachine includes a plurality of transition ducts disposed in a generally annular array and including a first transition duct and a second transition duct. Each of the plurality of transition ducts includes an inlet, an outlet, and a passage extending between the inlet and the outlet and defining a longitudinal axis, a radial axis, and a tangential axis, the outlet of each of the plurality of transition ducts offset from the inlet along the longitudinal axis and the tangential axis. The turbomachine further includes a support ring assembly downstream of the plurality of transition ducts along a hot gas path, and a plurality of mechanical fasteners connecting at least one transition duct of the plurality of transition ducts to the support ring assembly.

Abstract: A combustion chamber for a turbine engine, including an annular end wall provided with injection systems each centered on a respective axis and each having an upstream end forming a bushing for receiving a head of a fuel injector, and an annular shroud covering the end wall and including injector ports respectively arranged facing the injection systems, wherein the annular shroud includes air intake ports separate from the injector ports, and the bushing of each injection system crosses the corresponding injector port and includes at its upstream end a collar having a free end remote from the axis of the injection system by a first distance greater than a second distance separating a rim of the injector port from the axis.

Abstract: A heat shield for a combustor of a gas turbine engine includes a first edge with a first set of cantilevered members and a second edge with a second set of cantilevered members.

Abstract: A combustor assembly alignment system comprises an alignment plate comprising a plurality of alignment plate holes that align with a plurality of combustor assembly flange holes, an alignment plate securement system configured to secure the alignment plate to a combustor assembly flange by passing through a first alignment plate hole of the alignment plate and a first combustor assembly flange hole of the combustor assembly flange, and an alignment tube that extends away from the alignment plate, wherein a hollow interior of the alignment tube aligns with a second combustor assembly flange hole when the alignment plate is secured to the combustor assembly flange.

Abstract: A static component for a gas turbine engine includes an axially extending body comprising a forward end and an aft end disposed axially downstream from the forward end. A rib is formed on at least one of the forward end and the aft end of the axially extending body and extending axially from the axially extending body. A recess is formed in the rib.

Abstract: An arrangement for a gas turbine engine includes a combustor for producing a working medium by combustion of a mixture of fuel and an oxidant, a turbine section comprising a stationary vane carrier on which a first row of stationary vanes is arranged, and a transition duct for leading the working medium from the combustor to the turbine section. The transition duct has a forward end that adjoins the combustor and an aft end that adjoins the stationary vane carrier. The transition duct has a transition duct axis extending from the forward end to the aft end along a straight line. The transition duct axis is normal to a vane axis of a stationary vane in the first row of stationary vanes.

Abstract: A vane tip machining fixture assembly includes a first clamp ring mountable to a fixture, the first clamp ring includes a rigid back ring mounted to a resilient ring.

Abstract: A midframe portion (113) of a gas turbine engine (110) is provided, including a compressor section (112) with a last stage blade (124). The compressor section (112) is configured to introduce a radial velocity component into an air flow (111) such that the air flow is discharged from the compressor section (112) at a mixed direction based on a combined longitudinal velocity component and radial velocity component. The midframe portion (113) further includes a manifold (121) to directly couple the air flow from an outlet of the compressor section (112) to an inlet of a respective combustor head (118) of the gas turbine engine (110).

Abstract: An auto-tune controller and tuning process implemented thereby for measuring and tuning the combustion dynamics and emissions of a GT engine, relative to predetermined upper limits, are provided. Initially, the tuning process includes monitoring the combustion dynamics of a plurality of combustors and emissions for a plurality of conditions. Upon determination that one or more of the conditions exceeds a predetermined upper limit, a fuel flow split to a fuel circuit on all of the combustors on the engine is adjusted by a predetermined amount. The control system continues to monitor the combustion dynamics and to recursively adjust the fuel flow split by the predetermined amount until the combustion dynamics and/or emissions are operating within a prescribed range of the GT engine. Additionally, a method of automated extended turndown of a GT engine to find a minimum load is provided.

Abstract: A method predicts an amount of wear that is expected to occur on the tubes of a steam generator as a result of vibration against another structure within the steam generator. The method includes determining a volumetric amount of material that has been worn from a location on a tube over a duration of time and employing that volume as a function of time to determine the volume of material of the tube wall that is predicted to be worn from the tube or another tube at a future time. The volumetric-based analysis enables more accurately prediction of the wear depth at a future time. This enables the plugging of only those tubes that are determined from a volumetric analysis to be in risk of breach at the future time, thus slowing the rate at which tubes of a steam generator will be plugged.

Abstract: A combustion chamber of a gas turbine including first and second premixed fuel supply devices connected to a combustion device having first zones connected to the first premixed fuel supply devices and second zones connected to the second premixed fuel supply devices. The second fuel supply devices are shifted along a combustion device longitudinal axis with respect to the first fuel supply devices. The first zones are axially upstream of the second premixed fuel supply devices.

Abstract: A system includes a multi-tube fuel nozzle. The multi-tube fuel nozzle includes multiple mixing tubes. Each mixing tube includes an annular wall disposed about a central passage and an air inlet region configured to be disposed about a fuel injector extending into the central passage. The central passage extends from an upstream end to a downstream end of the annular wall relative to a direction of flow through the central passage. The air inlet region includes an air entry surface of the annular wall that gradually decreases in diameter in the direction of flow.

Abstract: The present application provides a combustor for use with a gas turbine engine. The combustor may include a liner and a flow sleeve surrounding the liner with the liner and the flow sleeve defining a flow path therebetween. A liner retaining feature extends into the flow path to retain the liner within the flow sleeve. The liner retaining feature may include a bolt therein.

Abstract: To provide a multifuel gas turbine combustor capable of combusting gases containing hydrogen in a high concentration with a low NOx while maintaining a low emission performance brought about by the pre-mixture combustion in the main burner, the gas turbine combustor includes a main burner (12) for supplying to and combusting a premixed gas (M), containing a first fuel (F1), within a first combustion region (S1) of a combustion chamber (10), and a supplemental burner (20) for supplying to and combusting a second fuel (F2) of a composition different from that of the first fuel (F1) within a second combustion region (S2) defined downstream of the first combustion region (S1) within the combustion chamber (10). The first fuel (F1) is of a hydrocarbon system and the second fuel (F2) is a gas containing hydrogen in a concentration exceeding the stable combustion limiting concentration of the hydrogen.