摘要:
A method is disclosed for forming a fuel feed passage in the feed arm of a fuel injector. The method includes the steps of providing a fuel feed passage in the feed arm of a fuel injector, whereby the fuel feed passage has an initial cross-sectional flow area that corresponds with an initial fuel flow velocity, an initial convection heat transfer coefficient and initial localized wetted wall temperatures for the fuel feed passage, for a given fuel flow rate and fuel temperature. The method further includes decreasing the initial cross-sectional flow area of the fuel feed passage so as to increase the fuel flow velocity and the convection heat transfer coefficient for the fuel feed passage, while lowering the localized wetted wall temperatures for the fuel feed passage, without varying the given fuel flow rate and fuel temperature.
摘要:
A method for operating a gas turbine engine facilitates reducing an amount of emissions from a combustor. The combustor includes a mixer assembly including a pilot mixer, a main mixer, and a centerbody that extends therebetween. The pilot mixer includes a pilot fuel nozzle and a plurality of axial swirlers. The main mixer includes a main swirler and a plurality of fuel injection ports. The method comprises injecting fuel into the combustor through the pilot mixer, such that the fuel is discharged downstream from the pilot mixer axial swirlers, and directing flow exiting the pilot mixer with a lip extending from the centerbody into a pilot flame zone downstream from said pilot mixer.
摘要:
The invention relates to a system for converting fuel and air into reformate with a reformer (10) which has a reaction space (12), a nozzle (14) for supplying a fuel/air mixture to the reaction space (12), and a fuel feed (16) for supplying fuel to the nozzle (14). As claimed in the invention it is provided that in the air inlet area (18) of the nozzle (14) there are air guidance means (40) which impart a swirl to the inflowing air.
摘要:
A combustion chamber assembly, in particular for a vehicle heating device, has combustion chamber housing in which a combustion chamber is bounded by a combustion chamber outer wall, the combustion chamber having a combustion chamber outlet aperture for the exit to a flame tube of exhaust gases produced during combustion, furthermore comprising a deflecting arrangement for deflecting at least a partial stream of the exhaust gases leaving the combustion chamber to flow along at least a partial region of the outer side of the combustion chamber outer wall facing away from the combustion chamber.
摘要:
The invention provides a method which includes the step of locating a burner of a low NOx boiler that produces a disproportionately high quantity of unburned carbon. The air-to-fuel ratio at the burner is then increased to decrease the percentage of unburned carbon attributable to the burner. The air-to-fuel ratio at a second burner of the low NOx boiler is reduced to maintain a substantially constant total air-to-fuel ratio in the low NOx boiler.
摘要:
The dual-fuel nozzle for a gas turbine and combustor includes a liquid fuel nozzle surrounded by a gas fuel nozzle. A converging sleeve surrounds the converging outer wall of the combined liquid fuel and gaseous nozzle to form a duct of decreasing cross-sectional area in a downstream direction whereby air flow through the duct accelerates toward the conical droplet spray pattern emerging from the liquid fuel nozzle. An inside swirler is located upstream of the liquid fuel tip to swirl the air flowing through the duct. An outer swirler is provided about the downstream end of the sleeve, likewise to swirl air. The accelerated swirling air flow through the duct and outer swirling air flow preclude impingement of oil spray droplets onto metal surfaces of the nozzle and hence prevent carbon deposition thereon which would otherwise be deleterious to the liquid fuel and gaseous nozzles.
摘要:
The dual-fuel nozzle includes a liquid fuel nozzle surrounded by an air/gas premixing cup. The cup has a base comprised of swirler vanes surrounding the outer tube of the liquid fuel nozzle. The tip of the liquid fuel nozzle extends to adjacent the open end of the premixing cup opposite the swirler vanes. The interior surface and outer surface of the premix cup and the tip of the liquid fuel nozzle, respectively, at the outer end of the cup are contoured, i.e., tapered complementarily inwardly to avoid recirculation of air in the annulus between the liquid fuel nozzle and the cup. Air recirculation is also prevented, thereby inhibiting flame holding adjacent the base of the cup by providing a smooth transition for air flow through the openings of the swirler at the base of the cup and into the annulus.
摘要:
A fuel injector for a gas turbine conbustor, the injector operating on gas and liquid fuels selectively. The injector has a central liquid fuel duct and jets, an annular gas duct and gas jets, and an outer annular combustion air duct. Operation on the liquid fuel tends to cause combustion products to be ingested into the gas orifices so impeding efficient gas combustion. The invention provides apertures (17) between the outer air duct and the intermediate gas duct whereby during operation on liquid fuel air bleeds into the gas duct and purges the gas orifices. As an added advantage, in a transition from liquid fuel to gas, the gas pressure is increased to a point where the air bleed is reversed and gas bleeds into the air duct. The pre-mixed gas/air is then emitted from swirlers surrounding the ring of gas jets. More efficient gas combustion results.
摘要:
Past systems have attempted to cool the combustor end or tip of fuel injection nozzles, however, such methods have failed to attain adequate cooling and life. The present system or structure for cooling a tip or combustion end of a fuel injection nozzle is accomplished with a twofold structure. First, a plurality of openings being acutely positioned in the combustor end about a plurality of base circles provide effective air-sweep cooling. Secondly, the convection cooling of a back face and a combustion face provides effective convection cooling. The two structures are combined to provide an effective, efficient cooling of the combustor end or tip. The combustor end of the fuel injection nozzle is maintained at a temperature low enough to prevent failure of the combustor end through oxidation, cracking and buckling and the air-sweep avoids carbon deposits on the combustor face.
摘要:
A burner having a burner body in which combustion air is injected in an air flow pattern which establishes a relatively stagnant air region positioned within the flow of combustion air. A pilot flame injector is positioned to generate a pilot flame extending into the stagnant air region. The pilot flame can, thus, be maintained during the operation of the burner because the stable air conditions within the stagnant air region minimize disruption of the pilot flame by the flow of combustion air.A method for maintaining a uniform pilot flame within a burner operating over a range of combustion air flow rates by introducing combustion air into the burner and providing the combustion air with a flow configuration that establishes a stagnant air zone within the burner that is relatively independent of the flow rate of the combustion air. The pilot flame is then positioned within the stagnant air zone.An injector for feeding finely divided fuel to a burner. The injector includes means to provide an annular passage through which air may flow at high velocity for discharge into a burner. Means are provided to feed fuel into the annular passage such that the fuel may be broken up into minute droplets by the air flow through the passage. Additionally the means to feed fuel are positioned to minimize contact between the fuel and the passage surfaces. Thus, the fuel may be broken up into minute droplets within the air flow stream with the finely divided fuel being discharged into a burner.