Abstract: A control system for use with a turbine engine that is configured to operate at a rated power output is provided. The control system includes a computing device that includes a processor that is programmed to calculate an amount of fluid to be supplied for combustion in the turbine engine. The processor is also programmed to designate at least one nozzle of a plurality of nozzles to receive the fluid. Moreover, the control system includes at least one control valve coupled to the computing device. The control valve is configured to receive at least one control parameter from the computing device for use in modulating the amount of the fluid to be channeled to the nozzle such that the rated power output is generated while emission levels are maintained below a predefined emissions threshold level.

Abstract: Systems and methods for preventing fuel leakage in a gas turbine engine are provided. A fuel accumulation system includes a control valve section fluidly coupled to a fuel manifold passage and an accumulator valve section fluidly coupled at a first side to the control valve section. The control valve section is configured to control expansion of a fluid flowing in the fuel manifold passage. The accumulator valve section is configured to receive fluid expanded in the fuel manifold passage via the control valve section.

Abstract: Burners having a fuel plenum in a base are disclosed. One disclosed example apparatus includes a base of a burner, the base comprising a fuel plenum and coupled to fuel nozzles, where at least one of the fuel nozzles is in fluid communication with the fuel plenum. The disclosed example apparatus also includes a burner head of the burner comprising nozzle passages in fluid communication with an airflow path, where the burner head defines a pilot combustion space that opens towards a flame tube of the burner, and is in fluid communication with the airflow path, and where each nozzle passage is to receive a fuel nozzle to provide fuel to entrain with air from the airflow path.

Abstract: A combustor for a gas turbine is provided. The combustor includes a pre-combustion chamber having a centre axis and a swirler which is mounted to the pre-combustion chamber. The swirler surrounds the pre-combustion chamber in a circumferential direction with respect to the centre axis. The swirler has a bottom surface which forms a part of a slot through which oxidant/fuel mixture is injectable into the pre-combustion chamber, wherein the bottom surface is located in a bottom plane. The swirler further includes a fuel injector which is arranged to the bottom surface such that a fuel is injectable into the slot with a fuel injection direction, wherein a first component of the fuel injection direction is non-parallel to the normal (n) of the bottom plane.

Abstract: A cooling circuit for a fuel nozzle in a gas turbine includes an end cap cavity receiving passive purge flow from a compressor of the turbine, and fuel nozzle swozzles disposed in a swozzle shroud that impart swirl to incoming fuel and air. Purge slots are formed in the swozzle shroud and through the fuel nozzle swozzles in fluid communication with the end cap cavity. The purge slots are positioned upstream of a quat fuel injection passage, and the passive purge flow enters fuel nozzle tip cavities of the fuel nozzle to provide tip cooling and tip purge volume without mixing the passive purge flow with quat fuel.

Abstract: A method for transferring fuel includes flowing water to at least one nozzle of a main fuel circuit. Also included is flowing oil to the at least one nozzle of the main fuel circuit. Further included is flowing liquid fuel to the at least one nozzle of the main fuel circuit, wherein flowing water to the at least one nozzle of the main fuel circuit occurs prior to flowing oil to the at least one nozzle of the main fuel circuit and flowing liquid fuel to the at least one nozzle of the main fuel circuit.

Abstract: There is provided a method for suppressing a generation of a yellow plume from a complex thermal power plant, the method being characterized in that, in a complex thermal power generating method including combusting fuel and compressed air for combustion, supplied to a combustor, to generate exhaust gas; generating power using the exhaust gas generated in the combusting; recovering heat of the exhaust gas by a heat recovery steam generator (HRSG) and generating power using the recovered heat and a steam turbine, and controlling an amount of supplied high thermal capacity gas supplying the high thermal capacity gas together with the fuel in the combusting, in such a manner that nitrogen dioxide is contained in the exhaust gas in an amount of 10 ppm or less (based on exhaust gas containing an oxygen concentration of 15%).

Abstract: It is proposed a gas turbine and a method to operate the gas turbine. A fluid is supplied to the gas turbine by means of fluid paths. A first fluid path is divided into a second and third fluid path. A first control valve controls a fluid mass flow in the first fluid path. A second control valve controls a ratio of fluid mass flows in the second and third fluid paths.

Abstract: A fuel control device and method of a gas turbine combustor, for advanced humid air turbines, in which plural combustion units comprising plural fuel nozzles for supplying fuel and plural air nozzles for supplying air for combustion are provided. A part of the plural combustion units are more excellent in flame stabilizing performance than the other combustion units. A fuel ratio, at which fuel is fed to the part of the combustion units is set on the basis of internal temperature of the humidification tower and internal pressure of the humidification tower to control a flow ratio of the fuel fed to the plural combustion units.

Abstract: Variable rate ignition method and system that take advantage of knowledge and analysis of environmental conditions and/or operational conditions. A variable ignition rate for igniting the engine permits an optimal use of the igniters and thereby prolongs their life as well as its associated maintenance schedule. Operating costs and durability are also enhanced. Furthermore, flexibility is enhanced since any changes to the method of determining the best spark rate can be made through update in the software of the engine controller instead of change in the hardware (e.g., the exciter).

Abstract: A mixer assembly for a gas turbine engine is provided, including a main mixer with fuel injection holes located between at least one radial swirler and at least one axial swirler, wherein the fuel injected into the main mixer is atomized and dispersed by the air flowing through the radial swirler and the axial swirler.

Abstract: The present application and the resultant patent provide a dual fuel combustor for a gas turbine engine. The combustor may include a primary premixer positioned within a head end plenum of the combustor, and a dual fuel, injection system positioned within the head end plenum and upstream of the premixer. The injection system may be configured to inject a gas fuel about an inlet end of the premixer when the combustor operates on the gas fuel. The injection system also may be configured to vaporize and inject a liquid fuel about the inlet end of the premixer when the combustor operates on the liquid fuel. The present application and the resultant patent also provide a related method of operating a dual fuel combustor.

Abstract: A fuel injector for a turbine engine may include a body member disposed about a longitudinal axis, and a barrel member located radially outwardly from the body member. The fuel injector may also include an annular passageway extending between the body member and the barrel member from a first end to a second end. The first end may be configured to be fluidly coupled to a compressor of the turbine engine and the second end may be configured to be fluidly coupled to a combustor of the turbine engine. The fuel injector may also include a perforated plate positioned proximate the first end of the passageway. The perforated plate may be configured to direct compressed air into the annular passageway with a first pressure drop. The fuel injector may also include at least one fuel discharge orifice positioned downstream of the perforated plate. The at least one fuel discharge orifice may be configured to discharge a fuel into the annular passageway with a second pressure drop.

Abstract: Systems and methods for pulse-width modulation of late lean liquid injection velocity can be provided by certain embodiments of the disclosure. In one embodiment, a gas turbine combustor utilizing a late lean injection scheme can be provided, wherein the combustor can include a combustor liner and a transition piece. Methods described herein can allow for dynamic and intelligent adjustment of the late lean injection scheme based on a duty cycle and, optionally, a measured combustion gases temperature profile. The adjustments can involve a pulse-width modification of the duty cycle, which in turn can affect a fuel introduction velocity. Dynamic control of the fuel introduction velocity can provide for improved fuel droplet penetration and moving the heat release zone away from walls of the transitional piece.

Abstract: A method is disclosed for controlling gas turbine operation in response to lean blowout of a combustion can. The gas turbine comprises a pair of combustion cans. The method includes sensing that a first combustion can is extinguished during a full load operation of the gas turbine, adjusting a fuel ratio between the fuel nozzles in each can, delivering a richer fuel mixture to the fuel nozzles nearest to the cross-fire tubes, generating a cross-fire from the second combustion can to the first combustion can, detecting a recovery of the turbine load, and adjusting the fuel ratio to the normal balanced fuel distribution between the fuel nozzles in each can.

Abstract: The invention refers to a sequential combustor arrangement including a first burner, a first combustion chamber, a dilution burner for admixing a dilution gas and a second fuel via a dilution-gas-fuel-admixer to the first combustor combustion products. The dilution-gas-fuel-admixer has at least one streamlined body which is arranged in the dilution burner for introducing the at least one second fuel into the dilution burner through at least one fuel nozzle, and which has a streamlined cross-sectional profile and which extends with a longitudinal direction perpendicularly or at an inclination to a main flow direction prevailing in the dilution burner. The streamlined body includes a dilution gas opening for admixing dilution gas into the first combustor combustion products upstream of the at least one fuel nozzle. The disclosure further refers to a method for operating a gas turbine with such a sequential combustor arrangement.

Abstract: An improved combustor for a gas turbine is operable to provide high combustion efficiency in a compact combustion chamber. The combustor includes a counter swirl doublet for improved fuel/air mixing. The enhanced combustor assembly and method of operation improves operation of the turbine.

Abstract: In a method for the low-CO emissions part load operation of a gas turbine with sequential combustion, the opening of the row of variable compressor inlet guide vanes is controlled depending on the temperatures of the operative burners of the second combustor and simultaneously the number of operative burners is kept at a minimum. This leads to low CO emissions at partial load of the gas turbine.

Abstract: A combustor for a gas turbine engine includes a combustion chamber and a fuel igniter assembly. The combustion chamber is defined by an annular inner combustor liner and an annular outer combustor liner. The fuel igniter assembly is coupled to the combustor and extends radially outward from the outer combustor liner. The fuel igniter assembly includes an igniter housing configured to house a fuel igniter therein, and a heat-dissipating element coupled to the igniter housing. The heat-dissipating element includes a plurality of fins configured to dissipate heat from the fuel igniter assembly.

Abstract: A gas turbine combustion system is provided. In an embodiment, the system includes a first radial inflow swirler having first radial outer intake openings, first radial inner outlet openings and first flow passages, each first flow passage including a first angle (a) with respect to the radial direction, a second radial inflow swirler having second radial outer intake openings, each second flow passage including a second angle (p) with respect to the radial direction, where the radial outer circumference of the second radial inflow swirler has a diameter that is smaller than the diameter of the radial inner circumference of the first radial inflow swirler and the second radial inflow swirler is located coaxially with and radially inside the first radial inflow swirler. The first angle (a) has a different sign than the second angle (p) with respect to the radial direction.

Abstract: A method for determining the optimum inlet geometry of a liquid rocket engine swirl injector includes obtaining a throttleable level phase value, volume flow rate, chamber pressure, liquid propellant density, inlet injector pressure, desired target spray angle and desired target optimum delta pressure value between an inlet and a chamber for a plurality of engine stages. The method calculates the tangential inlet area for each throttleable stage. The method also uses correlation between the tangential inlet areas and delta pressure values to calculate the spring displacement and variable inlet geometry of a liquid rocket engine swirl injector.

Abstract: A fuel injector for a gas turbine engine is provided. The fuel injector includes a central body, an air inlet duct, a mixing duct, a swirler, and a flow conditioner. The air inlet duct and the mixing duct are positioned around the central body to define an air flow passage. The swirler is positioned between the air inlet duct and the mixing duct. The flow conditioner is disposed in the air flow passage upstream with respect to the swirler. The flow conditioner has a perforated plate configured to uniformly distribute air circumferentially within the air inlet duct.

Abstract: A starting process for a gas turbine (28) that holds the turbine speed of rotation at an ignition speed setting during an ignition window (58), with the ignition speed setting being based on ambient air conditions to achieve a specified combustor air mass flow rate (52). A fuel flow rate may be set based on the fuel type and temperature to achieve a particular air/fuel ratio in a combustor. The fuel flow rate may be adjusted during the ignition window and thereafter based on a combustor inlet air temperature (46). Completion of ignition may be determined by a reduction (68) in a blade path temperature spread (66). After ignition, fuel flow is increased to accelerate the turbine to full speed. At any point, the fuel flow may be reduced, or its increase may be slowed, to avoid exceeding a temperature limit in the turbine.

Abstract: A system includes an oxidant compressor and a gas turbine engine turbine, which includes a turbine combustor, a turbine, and an exhaust gas compressor. The turbine combustor includes a plurality of diffusion fuel nozzles, each including a first oxidant conduit configured to inject a first oxidant through a plurality of first oxidant openings configured to impart swirling motion to the first oxidant in a first rotational direction, a first fuel conduit configured to inject a first fuel through a plurality of first fuel openings configured to impart swirling motion to the first fuel in a second rotational direction, and a second oxidant conduit configured to inject a second oxidant through a plurality of second oxidant openings configured to impart swirling motion to the second oxidant in a third rotational direction. The first fuel conduit surrounds the first oxidant conduit and the second oxidant conduit surrounds the first fuel conduit.

Abstract: The invention relates to a method for detecting a fuel leakage in the fuel distribution system between a fuel control valve and at least one burner of a gas turbine during the operation of the gas turbine. In order to detect a fuel leakage, the fuel consumption is approximated in accordance with the mechanical power of the gas turbine, the fuel amount fed to the fuel distribution system is determined, and the leakage flow is determined from the difference between the fed fuel amount and the fuel consumption. The invention further relates to a gas turbine for performing such a method.

Abstract: A combustion dynamics control system for an aviation based or land based gas turbine engine employs an acoustic driver that is configured to drive pressure perturbations across a premixed fuel injection orifice to substantially zero in response to a control signal such that fuel flow perturbations across the fuel injection orifice are substantially zero.

Abstract: A method of operating a gas turbine engine includes directing a stream of liquid fuel to the combustor through a nozzle of a dual fuel injector. The method may also include directing a first quantity of compressed air to the stream of liquid fuel proximate the nozzle, and directing a second quantity of compressed air to the stream of liquid fuel downstream of the nozzle. The second quantity of compressed air may be larger than the first quantity of compressed air. The method may further include delivering the compressed air and the stream of liquid fuel to the combustor in a substantially unmixed manner.

Abstract: An ignition system includes a housing defining an interior and an exhaust outlet. The housing is configured and adapted to be mounted to a combustor to issue flame from the exhaust outlet into the combustor for ignition and flame stabilization within the combustor. A fuel injector is mounted to the housing with an outlet of the fuel injector directed to issue a spray of fuel into the interior of the housing. An igniter is mounted to the housing with an ignition point of the igniter proximate the outlet of the fuel injector for ignition within the interior of the housing.

Abstract: A lean premix burner for a gas-turbine engine includes an annular center body (3) with a conically flaring fuel film applicator (11) supplied with fuel via an annular distributor chamber (14) and fuel channels (12) as well as air ducts (7, 9) with swirler elements (8, 10) provided on the outer and inner circumference. A fuel prefilmer lip (15) is attached to the fuel film applicator (11), with a flow area of a portion of the annular air ducts (7, 9) downstream of the swirler elements (8, 10) decreasing to accelerate the air swirled in correspondence with the airflow direction. By this, the fuel is transported positively without interim separation and without the occurrence of compressive oscillation—to a defined flow break-away edge (16), providing for a good mixture, high combustion efficiency and reduced formation of nitrogen oxide.

Abstract: A process of producing heat energy for use in heat exchange with other fluids and substances so as to impart said heat energy to said fluid or substances which includes several steps. In a first step, a mixture of fuel and oxidant is ignited in a combustion zone or zones (16, 18, 98, 122) to create a combusted fuel mix which in the form of shockwaves are carried away from the combustion zone or zones (16, 18, 98, 122) to provide a low pressure area within the combustion zone or zones (16, 18, 98, 122).

Abstract: A fuel injector includes pilot and main fuel injectors. The pilot fuel injector includes at least one pilot air swirler and the main fuel injector includes a main air blast fuel injector located between inner main and outer main air swirlers. A first air splitter is located between the pilot and inner main air swirlers and a second air splitter is located between the pilot and inner main air swirlers. The first air splitter has a downstream portion converging to a downstream end. The second air splitter has a downstream portion diverging to a downstream end. The second air splitter downstream end is downstream of the first air splitter downstream end and the ratio of the distance from the first air splitter downstream end to the second air splitter downstream end to the diameter of the second air splitter downstream end is in the range of 0.22 to 0.30.

Abstract: A gas turbine engine system includes a compressor, a combustor, and a turbine. The combustor is coupled to the compressor and disposed downstream of the compressor. The combustor includes a secondary combustor section coupled to a primary combustor section and disposed downstream of the primary combustor section. The combustor also includes a transition nozzle coupled to the secondary combustor section and disposed downstream of the secondary combustor section. The combustor further includes an injector coupled to the secondary combustor section, for injecting an air-fuel mixture to the secondary combustor section. The turbine is coupled to the combustor and disposed downstream of the transition nozzle; wherein the transition nozzle is oriented substantially tangential to the turbine.

Abstract: A turbomachine combustor is provided. The turbomachine includes a combustion chamber and multiple micro-mixer nozzles arranged concentrically within a radial combustion liner and configured to receive fuel from one or more fuel supply pipes affixed to each of the plurality of micro-mixer nozzles at an upstream face. The multiple micro-mixer nozzle are also configured to receive air from a flow sleeve surrounding the radial combustion liner. Each of the micro-mixer nozzles include an annular strip having a multiple tubes or passages extending axially from the upstream face to a downstream face of each of the micro-mixer nozzles.

Abstract: A device comprising a combustion toroid for receiving combustion-induced centrifugal forces therein to continuously combust fluids located therein and an outlet for exhaust from said combustion toroid.

Abstract: An igniter arranged to ignite combustion in a primary flow including a fuel and air mixture, the igniter including one or more geometric features arranged to: induce a shockwave flow structure at least partially disposed in the primary flow; and ignite the fuel and air mixture by virtue of the shockwave flow structure. The present disclosure also relates to a method of igniting combustion in a primary flow including a fuel and air mixture, the method including: providing one or more geometric features arranged to induce a shockwave flow structure; inducing the shockwave flow structure at least partially in the primary flow; and igniting the fuel and air mixture by virtue of the shockwave flow structure.

Abstract: Hybrid internal detonation-gas turbine engines incorporating detonation or pulse engine technology (such as an internal detonation engine), and methods of manufacturing and using the same are disclosed. The internal detonation engine includes a detonation chamber having a fuel igniter therein, a stator at one end of the detonation chamber having at least a first opening to receive fuel, a rotor adjacent to the stator, and an energy transfer mechanism configured to convert energy from igniting or detonating the fuel to mechanical energy. The detonation chamber and fuel igniter are configured to ignite or detonate a fuel in the detonation chamber. Either the stator or the detonation chamber has a second opening to exhaust detonation gas(es). The rotor has one or more third openings therein configured to overlap with at least the first opening as the rotor rotates.

Abstract: A combustor (10) includes a cap (16), a liner (20), a transition piece (24), and a combustion chamber (22) located downstream from the cap (16) and defined by the cap and liner. A secondary nozzle (40) circumferentially arranged around the liner (20) or transition piece (24) includes a center body, a fluid passage through the center body, a shroud circumferentially surrounding the center body, and an annular passage between the center body and the shroud. A method for supplying fuel to a combustor (10) includes flowing fuel through a primary nozzle radially disposed in a breech end of the combustor and flowing fuel through a secondary nozzle (40) circumferentially arranged around and passing through at least one of a liner (20) or a transition piece. The secondary nozzle (40) includes a center body, a fluid passage through the center body, a shroud circumferentially surrounding at least a portion of the center body (44), and an annular passage between the center body and the shroud.

Abstract: A fuel injection system for a gas turbine engine includes a fuel nozzle with a fuel injection aperture to inject a fuel jet and a multiple of airflow passages in the fuel nozzle to communicate a multiple of air streams to interact with the fuel jet.

Abstract: A system including a multi-tube fuel nozzle, including a first plate having a first plurality of openings, a plurality of tubes extending through the first plurality of openings in the first plate, wherein each tube of the plurality of tubes includes an air inlet, a fuel inlet, and a fuel-air mixture outlet, and a resilient metallic seal disposed along the first plate about the plurality of tubes.

Abstract: A system including a multi-tube fuel nozzle, including a plurality of tubes extending in an axial direction relative to a central axis of the multi-tube fuel nozzle, wherein each tube of the plurality of tubes includes an air inlet, a fuel inlet, and a fuel-air mixture outlet; and an inlet flow conditioner, including a plate extending in a radial direction relative to the central axis of the multi-tube fuel nozzle; an outer wall extending circumferentially about the plate, wherein the outer wall is coupled to the plate; and a plurality of air openings in the plate, the outer wall, or a combination thereof, wherein the plurality of air openings are disposed upstream from the air inlets in the plurality of tubes.

Abstract: A system including a first multi-tube fuel nozzle including a plurality of first tubes extending in an axial direction, wherein each first tube of the plurality of first tubes includes a first air inlet, a first fuel inlet, and a first fuel-air mixture outlet, a second multi-tube fuel nozzle including a plurality of second tubes extending in an axial direction, wherein each second tube of the plurality of second tubes includes a second air inlet, a second fuel inlet, and a second fuel-air mixture outlet, and an aft plate including a plurality of first tube apertures and a plurality of second tube apertures, wherein the plurality of first tubes extend to the plurality of first tube apertures, and the plurality of second tubes extend to the plurality of second tube apertures.

Abstract: A gas engine assembly includes a compressor, a combustion system, a bypass line and a control system. The control system is configured to control gas supply parameters based on a transportation delay value. The transportation delay value corresponds to a delay between a time when a gas supply control mechanism is adjusted and a time that gas having a corresponding adjustment of a gas characteristic is received at a predetermined point downstream from the gas supply control mechanism.

Abstract: There is provided a method for improving the combustion efficiency of a combustor of a gas turbine engine powering an aircraft. The method comprises selectively using two distinct fuel injection units or a combination thereof for spraying fuel in a combustion chamber of the combustor of the gas turbine engine. A first one of the two distinct fuel injection units is selected and optimized for high power demands, whereas a second one of the two distinct fuel injection units is selected and optimized for low power level demands. In operation, the fuel flow ratio between the two distinct injection units is controlled as a function of the power level demand.

Abstract: An ignition/chemical reaction promotion/flame holding device and a high-performance speed-type internal combustion engine using this device are provided, whereby ignition and the spreading and holding of flames can be dramatically improved in a gas turbine, a ram machine, a rocket engine, or another speed-type internal combustion engine. An ignition/chemical reaction promotion/flame holding device of a speed-type internal combustion engine comprises a spark plug for preparing charged particles in a predetermined location in a combustor of the speed-type internal combustion engine, and a microwave oscillator and antenna for inducing plasma with a working fluid in the combustor as a starter material by irradiating the charged particles and their surrounding vicinity with microwave pulses; wherein a region in which sufficient conditions for performing combustion are met is formed in the combustor by supplying an active chemical species produced from the working fluid by the effect of the plasma.

Abstract: A method and a device for controlling a lean fuel intake gas turbine engine, which can stably maintain operation of the gas turbine engine by preventing misfire and burnout of a catalytic combustor even when a catalyst in the combustor is deteriorated. A difference between measured temperatures of an inlet and an outlet of the combustor with respect to a methane concentration in an intake gas that is to be taken into the lean fuel intake gas turbine engine is compared with reference temperature difference data that is data indicating difference between temperatures of the inlet and the outlet of the combustor including a catalyst in its initial state to be a reference, and at least one of the inlet temperature and the outlet temperature of the combustor is controlled based on a difference between the measured temperature difference and the reference temperature difference data.

Abstract: A preparation of liquid fuel for combustion, particularly for ignition, in the burners of a gas turbine is proposed. A source of heated liquid fuel, particularly heated pressurized fuel, is arranged in a reservoir. The reservoir is arranged in parallel with a main fuel feed of a combustion system. The reservoir can be filled by the main fuel feed and/or evacuated into the main fuel feed. The reservoir contains a heating means, which heat the liquid fuel filled in the reservoir, particularly while circulating in the reservoir.

Abstract: A turbine engine for an aircraft including a turbine engine shaft and a pumping module, including: a pump shaft, connected to the turbine engine shaft; a pump for supplying fuel to the turbine engine, mounted on the pump shaft, configured to deliver a flow of fuel as a function of a speed of rotation of the turbine engine shaft; and an electrical device mounted on the pump shaft and configured, according to a first mode of operation, to drive the pump shaft in rotation to actuate the supply pump and, according to a second mode of operation, to be driven in rotation by the pump shaft to supply electrical power to equipment of the turbine engine.

Abstract: A fuel system for an aircraft comprises a boost pump, a main fuel pump and a motive pump. The boost pump receives fuel from a storage unit. The main fuel pump receives fuel from the boost pump and delivers fuel to a distribution system. The motive fuel pump receives fuel from the boost pump, routes fuel through the storage unit, and delivers fuel to an actuator.

Abstract: A gas turbine engine combustion system including a mixing duct that separates into at least two branch passages for the delivery of a fuel and working fluid to distinct locations within a combustion chamber. The residence time for the fuel and working fluid within each of the two branch passages is distinct.

Abstract: A fuel nozzle system for enabling a gas turbine to start and operate on low-Btu fuel includes a primary tip having primary fuel orifices and a primary fuel passage in fluid communication with the primary fuel orifices, and a fuel circuit capable of controlling flow rates of a first and second low-Btu fuel gases flowing into the fuel nozzle. The system is capable of operating at an ignition status, in which at least the first low-Btu fuel gas is fed to the primary fuel orifices and ignited to start the gas turbine, and a baseload status, in which at least the second low-Btu fuel gas is fired at baseload. The low-Btu fuel gas ignited at the ignition status has a content of the first low-Btu fuel gas higher than that of the low-Btu fuel gas fired at the baseload status. Methods for using the system are also provided.