Abstract: The present application provides for a combustor for use with a gas turbine engine. The combustor may include a cap member and a number of fuel nozzles extending through the cap member. One or more of the fuel nozzles may be provided in a non-flush position with respect to the cap member.

Abstract: An integrated plate is provided for use with a combustor including a casing, a fuel plenum extending circumferentially about the casing, and a fuel nozzle extending axially through the casing. The integrated plate includes a plurality of fuel injection pegs that extend radially between the fuel plenum and the fuel nozzle.

Abstract: When starting a dual fuel turbine engine on liquid fuel, a flow of air assist into a combined pilot gaseous fuel and air assist tube is supplied. The velocity of the flow of air assist is increased as it is expelled through an outlet of the tube. The flow of air assist is directed into a first end of a pilot injector barrel. Additional air is drawn into the first end of the pilot injector barrel from an enclosure containing both the first end of the pilot injector barrel and the tube outlet. Liquid pilot fuel is supplied at a second end of the pilot injector barrel, and this fuel is atomized by the flow of the air assist and additional air.

Abstract: A combustor (10) includes a combustion chamber (18), a liner (12) surrounding the combustion chamber, and a flow sleeve (52) surrounding the liner. An annular passage is between the liner and the flow sleeve, and a fuel injector (50) is located partially in the annular passage and extending through the liner into the combustion chamber. The fuel injector includes an outer tube, an inner tube, and a flow passage. A method of supplying a fuel to a combustor includes flowing a diluent inside an outer tube extending along a liner and flowing a liquid or gaseous fuel inside an inner tube extending inside a portion of the outer tube. The method further includes flowing the diluent and the liquid or gaseous fuel through the liner and into a combustion chamber surrounded by the liner.

Abstract: A method of transitioning from a first operating mode to a second operating in a gas turbine engine. An amount of fuel provided to a primary fuel injection system of the combustor apparatus is reduced. An amount of fuel provided to a secondary fuel/air injection system of the combustor apparatus is reduced, wherein the secondary fuel/air injection system provides fuel to a secondary combustion zone downstream from a main combustion zone. A total amount of air provided to the combustor apparatus is reduced, wherein portions of the air are provided to each of the injection systems. Upon reaching operating parameters corresponding to the second operating mode, the amount of fuel provided to the primary fuel injection system is increased, the amount of fuel provided to the secondary fuel/air injection system is reduced, and the total amount of air provided to the combustor apparatus is increased.

Abstract: In a temperature estimation apparatus for an aeroplane gas turbine engine, there are provided with a calculator that calculates a low-pressure turbine outlet temperature change (dEGT) based on low-pressure turbine rotational speed (N1) and ambient temperature (T1), a calculator that calculates a model outlet temperature (MODEL-EGTC) based on corrected high-pressure turbine rotational speed (N2C) and atmospheric pressure (P0) to calculate a model outlet temperature difference (dEGTC) by subtracting the calculated temperature (MODEL-EGTC) from a corrected low-pressure turbine outlet temperature (EGTC), a calculator that calculates a correction amount (dEGTad) relative to the model outlet temperature difference (dEGTC) based on the model outlet temperature difference (dEGTC) and low-pressure turbine rotational speed (N1), and a calculator that calculates an estimation value of the low-pressure turbine inlet temperature (ITT) based on the low-pressure turbine outlet temperature (EGT), etc.

Abstract: A turbomachine including a combustor in which fuel is combustible to produce a working fluid, a turbine section, which is receptive of the working fluid for power generation operations, a transition piece in which additional fuel is combustible, the transition piece being disposed to transport the working fluid from the combustor to the turbine section and a staged combustion system coupled to the combustor and the transition piece. The staged combustion system is configured to blend components of the fuel and the additional fuel in multiple modes.

Abstract: The burner of a gas turbine includes a swirl generator and, downstream of it, a mixing tube. The swirl generator is defined by at least two walls facing one another to define a conical swirl chamber and is provided with nozzles arranged to inject a fuel and apertures arranged to feed an oxidiser into the swirl chamber. The burner includes a lance which extends along a longitudinal axis of the swirl generator and is provided with side nozzles for ejecting a fuel within the burner. The side nozzles have their axes inclined with respect to the axis of the lance and can be positioned along the axis of the burner.

Abstract: A fuel metering valve system for use with a flow of fuel in a gas turbine engine may include a number of orifice plate lines, a number of differently sized orifice plates, and a number of orifice plate line valves. One of the orifice plate line valves opens and closes one of the orifice plates on the orifice plate lines.

Abstract: A combustor (10) includes a liner (12) that defines a combustion chamber (18) first pre-mix chamber (14) is upstream of the combustion chamber, and a fuel plenum (40) in fluid communication with the first pre-mix chamber surrounds a least a portion of the first pre-mix chamber. A method of supplying a fuel to combustor includes flowing the fuel over an outer surface of a first pre-mix chamber and into the first pre-mix chamber.

Abstract: The present application provides a micro-mixer combustion nozzle for mixing a flow of fuel and a flow of air in a gas turbine engine. The micro-mixer combustion nozzle may include a fuel plate with a number of fuel plate apertures and a fuel plate passage in communication with the flow of fuel and an air plate with a number of air plate apertures and an air plate passage in communication with the flow of air. The fuel plate passage and the air plate passage may align to mix in part the flow of fuel and the flow of air.

Abstract: A method and apparatus are disclosed for mixing H2-rich fuels with air in a gas turbine combustion system, wherein a first stream of burner air and a second stream of a H2-rich fuel are provided. All of the fuel is premixed with a portion of the burner air to produce a pre-premixed fuel/air mixture. This pre-premixed fuel/air mixture is injected into the main burner air stream.

Abstract: A system is provided with a turbine combustor having a first diffusion fuel nozzle, wherein the first diffusion fuel nozzle has first and second passages that separately inject respective first and second flows into a chamber of the turbine combustor to produce a diffusion flame. The first flow includes a first fuel, and the second flow includes a first oxidant and a first diluent. The system includes a turbine driven by combustion products from the diffusion flame in the turbine combustor. The system also includes an exhaust gas compressor, wherein the exhaust gas compressor is configured to compress and route an exhaust gas from the turbine to the turbine combustor along an exhaust recirculation path.

Abstract: A system is provided with a turbine combustor having a first diffusion fuel nozzle, wherein the first diffusion fuel nozzle has first and second passages that separately inject respective first and second flows into a chamber of the turbine combustor to produce a diffusion flame. The first flow includes a first fuel and a first diluent, and the second flow includes a first oxidant. The system includes a turbine driven by combustion products from the diffusion flame in the turbine combustor. The system also includes an exhaust gas compressor, wherein the exhaust gas compressor is configured to compress and route an exhaust gas from the turbine to the turbine combustor along an exhaust recirculation path.

Abstract: An arrangement for a combustion chamber the arrangement comprising a combustion chamber, an injector for injecting fuel into the combustion chamber and an igniter for supplying a spark for igniting fuel so injected, wherein the injector has a passage through which air is supplied to the combustion chamber in use, the igniter being positioned upstream of the combustion chamber such that a spark generated by the igniter is conveyed along the passage by the injector air.

Abstract: A system and method for reducing combustion dynamics includes first and second combustors, and each combustor includes a fuel nozzle and a combustion chamber downstream from the fuel nozzle. Each fuel nozzle includes an axially extending center body, a shroud that circumferentially surrounds at least a portion of the axially extending center body, a plurality of vanes that extend radially between the center body and the shroud, a first fuel port through at least one of the plurality of vanes at a first axial distance from the combustion chamber, the plurality of vanes being located at a second axial distance from the combustion chamber. A second fuel port is provided through the center body at a third axial distance from the combustion chamber. The system further includes structure for producing a combustion instability frequency in the first combustor that is different from the combustion instability frequency in the second combustor.

Abstract: The present invention relation to a burner for a combustion chamber of a gas turbine with a mixing and injection device. The mixing and injection device includes a limiting wall that defines a gas-flow channel and at least two streamlined bodies, each extending in a first transverse direction into the gas-flow channel. Each streamlined body has two lateral surfaces that are arranged essentially parallel to the main-flow direction, the lateral surfaces being joined to one another at their upstream side to form a leading edge of the body and joined at their downstream side to form a trailing edge of the body. Each streamlined body has a cross-section perpendicular to the first transverse direction that is shaped as a streamlined profile.

Abstract: A nozzle formed of one piece for a jet engine includes a mixing tube, a fuel conduit integrally formed with the mixing tube, and an opening through the fuel conduit and directed radially into the mixing tube.

Abstract: A laser ignition system for an internal combustion engine, and more specifically a gas turbine engine, is provided. The system comprises at least one laser light source configured to generate a laser beam and an optical beam guidance component. The optical beam guidance component is configured to transmit the laser beam to irradiate on an oxygenated fuel mixture supplied into the combustion chamber at a region of highest ignitability to generate a combustor flame in a flame region. The system further includes an integrated control diagnostic component configured to detect at least a portion of a light emission and operable to control one or more combustion parameters based in part on the detected light emission. The system further includes additional enhanced ignition control configurations. A method for igniting a fuel mixture in an internal combustion engine is also presented.

Abstract: A cooling system for a gas turbine engine (10). The system is comprises a fuel air heat exchanger (78) comprising a fuel passage (80) in thermal contact with an engine cooling air passage (82). The system further comprises a fuel deoxygenator (72) located upstream of the fuel air heat exchanger (78) configured to deliver deoxygenated fuel to the fuel air heat exchanger fuel passage (80). The system includes a valve (84) configured to moderate engine cooling air flow to the engine cooling air passage (82).

Abstract: A fuel injector nozzle assembly includes a body extending along an axis and a core swirl plug positioned at least partially within the body. The core swirl plug has a flow modifying structure configured to swirl fuel at a location upstream from a distal end of the nozzle assembly.

Abstract: The present invention discloses a novel apparatus and method for a mixing fuel and air in a gas turbine combustion system. The mixer helps to mix fuel and air while being able to selectively increase the fuel flow to a shear to a shear layer of a pilot flame in order to reduce polluting emissions. The mixer directs a flow of air radially inward into the combustion system and includes two sets of fuel injectors within each radially-oriented vane. A first plurality of fuel injectors operate independent of a second plurality of fuel injectors and the second plurality of fuel injectors are positioned to selectively modulate the fuel flow to the shear layer of the resulting pilot flame.

Abstract: An apparatus and method for controlling a pressure drop of a fluid is disclosed. A sleeve includes a plurality of flow passages in a wall of the sleeve. A member slides relative to the sleeve to reveal at least a portion of the plurality of flow passages to control flow of the fluid through the flow passages. The plurality of flow passages are at azimuthally- and axially-staggered locations around the sleeve.

Abstract: An injection device including at least one injection plate adjacent a combustion space of a combustion chamber, and at least one first injection nozzle including a first entry bore having a first discharge into the combustion chamber, and a first orifice bore, having a cross-sectional dimension less than or equal to the first entry bore, coaxially arranged with the first entry bore and remote from the first discharge. At least one second injection nozzle includes a second entry bore having a second discharge into the combustion chamber, and a second orifice bore, having a cross-sectional dimension less than or equal to the second entry bore, coaxially arranged with the second entry bore and remote from the second discharge. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

Abstract: A fuel flow passes through a micromixer section of a gas turbine that includes a plurality of mixing tubes for transporting a fuel/air mixture and a distribution plate including a plurality of distribution holes and a plurality of tube holes for accommodating the mixing tubes. Each of the mixing tubes includes a plurality of fuel holes through which fuel enters the mixing tubes. The tube holes and the mixing tubes form a plurality of annulus areas between the distribution plate and the mixing tubes. The distribution holes and the annulus areas are configured to pass the fuel flow through the distribution plate toward the fuel holes. A flow management device modifies an effective size of the annulus areas to control a distribution of the fuel flow through the distribution holes and the annulus areas of the distribution plate to provide a uniform fuel/air composition in each of the mixing tubes.

Abstract: A system, including a turbine fluid supply system, including a fuel supply assembly, including a first fuel supply configured to supply a first fuel to a gas turbine engine; and a second fuel supply configured to supply a second fuel to the gas turbine engine, wherein the first fuel has a greater carbon content than the second fuel, and a diluent supply assembly comprising at least one diluent supply configured to supply at least one diluent to the gas turbine engine; and a controller having instructions to control the first fuel supply, the second fuel supply, or the at least one diluent supply to adjust a percentage of carbon in a combustor of the gas turbine engine to maintain a ratio of carbonaceous emissions in an exhaust gas per unit of energy produced by the gas turbine engine at or below a threshold ratio.

Abstract: Disclosed is a method of operating a secondary fuel nozzle for a turbomachine combustor including delivering a flow of pilot fuel through a pilot fuel channel toward a combustion zone and delivering a flow of air through a plurality of transfer passages arranged around the pilot fuel channel toward the combustion zone. The flow of pilot fuel and the flow of air are combusted in the combustion zone, and a flow of transfer fuel is delivered through the plurality of transfer passages for combustion. A secondary fuel nozzle includes a pilot fuel channel extending along the fuel nozzle to deliver a flow of pilot fuel to a combustion zone. A plurality of transfer passages are arranged around the pilot fuel channel and are configured to deliver a flow of air for combustion with the flow of pilot fuel and to deliver a flow of transfer fuel to the combustion zone.

Abstract: A mixture of air and fuel is received into a reaction chamber of a gas turbine system. The fuel is oxidized in the reaction chamber, and a maximum temperature of the mixture in the reaction chamber is controlled to be substantially at or below an inlet temperature of a turbine of the gas turbine system. The oxidation of the fuel is initiated by raising the temperature of the mixture to or above an auto-ignition temperature of the fuel. In some cases, the reaction chamber may be provided without a fuel oxidation catalyst material.

Abstract: Methods and devices for anticipating a surge in a gas turbine engine. Controlled pressure signal(s) may be compared with reference pressure signal(s), each of the controlled pressure signal(s) and reference pressure signal(s) having an associated time value. If the controlled pressure signal(s) are less than the reference pressure signal(s), a controlled pressure curve may be fitted through a predetermined number of points based on the controlled pressure value(s) and associated time value(s). A reference pressure curve may be fitted through the predetermined number of points based on the reference pressure value(s) and associated time value(s). A time to compressor surge may be estimated based on an intersection of the controlled pressure curve and the reference pressure curve.

Abstract: A portable on-demand hydrogen supplemental system producing hydrogen gas and mixing the hydrogen gas with the air used for combustion of the jet fuel to increase the combustion efficiency of said jet fuel. Hydrogen increases the laminar flame speed of the jet fuel during combustion thus causing more fuel to be burned and lowering particulate matter emissions. Hydrogen is supplied to the jet engine at levels well below it lower flammability limit in air of 4%. Hydrogen and oxygen is produced by an electrolyzer from nonelectrolyte water in a nonelectrolyte water tank. The system utilizes an onboard diagnostic (OBD) interface in communication with the jet's control systems, to regulate power to the system so that hydrogen production for the jet engine only occurs when the jet engine is running. The hydrogen gas produced is immediately consumed by the jet engine. No hydrogen is stored on, in or around the jet.

Abstract: A device for injecting fuel into a combustion chamber of a gas turbine is provided, having a distribution section to which a first fuel channel, a second fuel channel and an injection channel are coupled. The first fuel channel and the second fuel channel are arranged such that a) fuel is transportable by one of the first fuel channel and the second fuel channel to the distribution section, and b) a first quantity of fuel is transportable by the other one of the first fuel channel and the second fuel channel out of the distribution section. The injection channel is arranged such that a second quantity of fuel is injectable from the distribution section into the combustion chamber. The device further comprises an end cap with a protrusion having the injection channel inside, and extending inside the inner tube.

Abstract: A combustor including a combustion nozzle. The combustion nozzle includes a mixing section and an exit section. The mixing section includes an air inlet, and a fuel inlet. The exit section includes a plurality of jets on an exit surface. The combustor further includes a combustion zone, including a combustion liner, disposed downstream and in fluidic communication with the combustion nozzle. The combustor is configured wherein a, NOx emission of the combustor is related to 1/R, where R is a Reynolds number ratio of a jet of the plurality of jets to the combustion liner. A method for achieving NOx reduction in a combustion nozzle.

Abstract: A method of heating liquid fuel upstream of a combustor in a system where compressor discharge air is cooled before being supplied to fuel nozzles in the combustor includes the steps of passing the compressor discharge air through a heat exchanger in heat exchange relationship with the liquid fuel to heat the liquid fuel and cool the compressor discharge air; supplying the heated liquid fuel and the cooled compressor discharge air to the combustor.

Abstract: The invention concerns a method for mixing a dilution air with a hot main flow in sequential combustion system of a gas turbine, wherein the gas turbine essentially comprises at least one compressor, a first combustor which is connected downstream to the compressor, and the hot gases of the first combustor are admitted to at least one intermediate turbine or directly or indirectly to at least one second combustor. The hot gases of the second combustor are admitted to a further turbine or directly or indirectly to an energy recovery, wherein at least one combustor runs under a caloric combustion path having a can-architecture. At least one dilution air injection is introduced into the first combustor, and wherein the direction of the dilution air injection is directed against or in the direction of the original swirl flow inside of the first combustor.

Abstract: An integrated exciter-igniter architecture is disclosed that integrates compact, direct-mounted exciter electronics with an aerospace designed igniter to reduce overall ignition system complexity. The integrated exciter-igniter unit hermetically seals exciter electronics within a stainless steel enclosure or housing. The stainless enclosure enables the exciter electronics to remain near atmospheric pressure while the unit is exposed to vacuum conditions. The exciter electronics include a DC-DC converter, timing circuitry, custom-designed PCBs, a custom-designed main power transformer, and a high voltage ignition coil. All of which are packaged together in the stainless steel enclosure. The integrated exciter-igniter unit allows for efficient energy delivery to the spark gap and eliminates the need for a high voltage cable to distribute the high voltage, high energy pulses.

Abstract: Systems and methods for controlling fuel flow within a machine are provided. A plurality of fuel types provided to the machine and a plurality of fuel circuits associated with the machine may be identified, each of the plurality of fuel circuits adapted to be provided with one or more of the plurality of fuel types. A fuel flow parameter for calculating fuel flow may be identified, and a respective fuel flow for each of the one or more fuel types provided to each of the plurality of fuel circuits may be calculated based at least in part on the identified fuel flow parameter. Based at least in part on the calculation of the respective fuel flows, operation of one or more fuel flow control devices providing fuel to the plurality of fuel circuits may be controlled.

Abstract: The present invention relates to a method for controlling the fuel temperature of a gas turbine, where parameters are determined as input values, where the parameters are compared with emission-optimized nominal values and an optimum fuel temperature is determined, and where the fuel to be supplied to a combustion chamber is heated or cooled.

Abstract: The present application provides a combustor for use with a gas turbine engine. The combustor may include a number of fuel nozzles and a combustion zone downstream of the fuel nozzles. The combustion zone may include a number of steps such that the combustion zone expands in a radial direction downstream of the fuel nozzles.

Abstract: According to various embodiments, a system includes a fuel controller configured to control a fuel transition between a first flow of a first fuel and a second flow of a second fuel into a fuel nozzle of a combustion system. The fuel controller is configured to adjust a third flow of a diluent in combination with the second flow of the second fuel to maintain a pressure ratio across the fuel nozzle above a predetermined operating pressure ratio.

Abstract: In one embodiment, a system for reducing pressure oscillations within a gas turbine engine includes at least one fuel injector configured to inject fuel into a combustor. The system also includes a valve fluidly coupled to the at least one fuel injector. The system further includes a controller communicatively coupled to the valve. The controller is configured to cycle the valve between an open position and a closed position at a first frequency and a first duty cycle while a magnitude of pressure oscillations within the combustor is less than a threshold value, to cycle the valve between the open position and the closed position at a second frequency and a second duty cycle while the magnitude of the pressure oscillations within the combustor is greater than or equal to the threshold value, and to adjust the second frequency based on a measured frequency of the pressure oscillations.

Abstract: A liquid fuel assist ignition system for providing a fuel/air mixture to a gas turbine in its start-up phase includes a high pressure tank, a vacuum pump connected to the high pressure tank, a liquid fuel inlet connected to the high pressure tank, an air inlet connected to the high pressure tank, and an outlet of the high pressure tank connected to a burner of the gas turbine.

Abstract: A combustion chamber including a first fuel injector and a second fuel injector, the first and second fuel injectors being arranged to inject fuel into a mainstream flow of air with the second fuel injector arranged downstream of the first fuel injector. A method of mixing fuel and air in a combustion chamber, including injecting fuel into a mainstream flow of air with a first fuel injector; injecting fuel into the mainstream flow of air with a second fuel injector, which is arranged downstream of the first fuel injector; injecting fuel into the mainstream flow with the first fuel injector such that the resulting mixture between the first and second fuel injectors has an equivalence ratio less than the lean flame stability limit; and injecting fuel into the mainstream flow with the second fuel injector such that a combustion zone is provided downstream of the second fuel injector.

Abstract: A method is provided for fuel injection in a sequential combustion system comprising a first combustion chamber and downstream thereof a second combustion chamber, in between which at least one vortex generator is located, as well as a premixing chamber having a longitudinal axis downstream of the vortex generator, and a fuel lance having a vertical portion and a horizontal portion, being located within said premixing chamber. The fuel injected is an MBtu-fuel. In said premixing chamber the fuel and a gas contained in an oxidizing stream coming from the first combustion chamber are premixed to a combustible mixture. The fuel is injected in such a way that the residence time of the fuel in the premixing chamber is reduced in comparison with a radial injection of the fuel from the horizontal portion of the fuel lance.

Abstract: A turbomachine including: a combustion chamber, with a fuel injection device in the combustion chamber; a supply mechanism supplying fuel to the fuel injection device; a mechanism determining instantaneous variation of fuel flow rate of the supply mechanism; and a regulation mechanism regulating the fuel flow rate of the injection device according to the instantaneous variation of the fuel flow rate of the supply mechanism determined by the determination mechanism.

Abstract: A method of co-firing fuel within a gas turbine engine. The method may include injecting a first fuel into a combustion system of a gas turbine engine. The first fuel may include a high energy liquid fuel. The method may also include injecting a second fuel into the combustion system. The second fuel may include a gaseous low Wobbe fuel. Only the first fuel may be injected during a first mode of operation. The first fuel and the second fuel may be injected simultaneously and discretely during a second mode of operation.

Abstract: An LNG fuel system for gas turbine engine systems is disclosed that allows more efficient management of cryogenic fuels such as LNG to reduce emissions and improve engine efficiency. In one configuration, an intercooled, recuperated gas turbine engine comprises an LNG tank incorporating a liquid-to-vapor LNG fuel circuit in parallel with a vapor fuel circuit. In a second configuration, an alternate vapor fuel circuit is disclosed. In either configuration, the fuel in the liquid fuel circuit is vaporized and heated by the engine's intercooler or by both the engine's intercooler and/or a heat exchanger on the exhaust. In another configuration, both the fuel in the liquid-to-vapor LNG fuel circuit and the vapor fuel circuit are heated by a heat exchanger on the exhaust.

Abstract: A laser ignition system for an internal combustion engine, and more specifically a gas turbine engine, is provided. The system including a laser light source configured to generate a laser beam, an ignition port configured to provide optimized optical access of the laser beam to a combustion chamber and an optical beam guidance component disposed between the laser light source and the ignition port. The optical beam guidance component is configured to include optimized optic components to transmit the laser beam to irradiate on a fuel mixture supplied into the combustion chamber to generate a combustor flame in a flame region. A method for igniting a fuel mixture in an internal combustion engine is also presented.

Abstract: An object of the present invention is to provide a gas turbine combustor that supports hydrogen-containing gas having a high burning velocity and is capable of performing low NOx combustion without reducing reliability of a burner. A first fuel nozzle is provided upstream of a combustion chamber and supplies fuel for activation and hydrogen-containing gas. The combustor has a primary combustion zone, a reduction zone and a secondary combustion zone. In the primary combustion zone, the fuel supplied from the first fuel nozzle is combusted under a fuel rich condition to form a burned gas containing a low concentration of oxygen. In the reduction zone, a hydrogen-containing gas is injected into the combustion chamber through a second fuel injection hole from a second fuel nozzle so that NOx generated in the primary combustion zone is reduced by an oxygen reaction of the hydrogen.

Abstract: A hybrid combustor combines two distinct fuel injection sources to spray fuel in the combustor. The combustor combines a rotary fuel slinger for spraying fuel in a first combustion zone during high power level and cruise conditions and a set of fuel nozzles for spraying fuel in a second combustion zone during lower power level and starting conditions.

Abstract: A fuel delivery system for use, for example in a gas turbine engine system, includes a fuel metering unit including a main fuel inlet. The fuel metering unit includes fuel pressure and temperature sensors. A cavitating venturi is in fluid communication with the main fuel inlet and includes venturi characteristics such as throat diameter. A fuel nozzle is in fluid communication with the venturi for delivering fuel to the gas turbine engine. A controller is connected to the pressure temperature sensors and is operable to calculate a flow rate of fuel through the nozzle based upon the signals from the pressure and temperature sensors and the fuel and venturi characteristics. A variable cavitating venturi may be arranged within the throat to vary the area and adjust the flow rate through the venturi. The cavitating venturi can also be used at the fuel nozzle to further simplify the fuel delivery system.