Abstract: A combustor for burning heavy residual fuel to drive a gas turbine engine has an elongated, imperforate vaporizing tube with an air blast nozzle at one end of the tube adjacent a cannister type preheater means arranged to swirl air blasted residual fuel in the tube to produce vaporization while preventing autoignition and wherein the vaporized fuel is processed through a primary crossed slot air mixer means for reducing the temperature of the air/fuel mixture passing from the vaporizing tube and to establish an equivalence ratio in the air/fuel mixture at a lean reaction zone combustion chamber for burning a lean air/fuel mixture from the primary air mixer means under controlled conditions and wherein a combustor torch igniter directs an igniting flame into the lean air/fuel mixture directed from the air mixer means so as to assure continuous combustion in the lean combustion zone so as to reduce hydrocarbon and carbon monoxide emissions from the combustion apparatus under varying conditions of gas turbine en
September 22, 1980
Date of Patent:
November 1, 1983
General Motors Corporation
Allen S. Novick, Jerry G. Tomlinson, Dennis L. Troth
Abstract: A gas turbine engine has a compressor and power turbine driven by gas flow across a nozzle arrangement that includes a partial admission gate valve therein movable into and out of overlying relationship with a limited number of vanes of the nozzle in order to control power output therefrom during part load operation of the engine. Each gate has a flat downstream face. The gates are moved between stored and blocking positions. Each gate face is engageable with flat valve seat surfaces on nozzle vanes when in the blocking position whereby motive gas pressure will hold the gates sealed against the seats.
Abstract: A gas turbine engine has a metal engine block which houses interconnected ceramic duct components defining the gas flow path between a combustor and turbine stages of a two spool gas turbine engine. The ceramic duct components are coupled to the engine block by support cages that accommodate thermal expansion of the duct components to prevent excessive stress levels within the ceramic components throughout a wide range of turbine engine operating conditions.
Abstract: An air blast nozzle includes a ring of air swirler vanes therein for producing a first turbulent flow of air therethrough and a turbulence generator located within the air flow through said swirler vanes to produce an intensification of the turbulent flow of the air swirl produced by the swirler vanes. The intensified swirled air is immediately directed into mixed flow relationship with fuel from said air blast nozzle to maintain increased turbulence intensity at the fuel from said nozzle without attenuation of the air energy level prior to burning of the air/fuel mixture so as to improve combustor efficiency by evaporation rate control due to decreased fuel droplet size attributable to the turbulence intensification.
Abstract: A combustor for a gas turbine engine includes a metal engine block including a wall portion defining a housing for a combustor having ceramic liner components. A ceramic outlet duct is supported by a compliant seal on the metal block and a reaction chamber liner is stacked thereon and partly closed at one end by a ceramic bypass swirl plate which is spring loaded by a plurality of circumferentially spaced, spring loaded guide rods and wherein each of the guide rods has one end thereof directed exteriorly of a metal cover plate on the engine block to react against externally located biasing springs cooled by ambient air and wherein the rod spring support arrangement maintains the stacked ceramic components together so that a normal force is maintained on the seal between the outlet duct and the engine block under all operating conditions.
Abstract: A rotary regenerator disc matrix has a face seal with a cross arm and arcuate rim segments joined by prestress clamps to prestrain the arcuate rim seals so as to compensate seal rim twisting or coning and resultant disc face seal leakage as produced by operating thermal gradients across the seal.
Abstract: A dry coal fuel supply system for a gas turbine engine includes a continuous loop conveyor pump having a plurality of positive displacement pistons connected by a cable and driven by a variable speed motor with respect to an atmospheric reservoir filled with powdered coal and the continuous loop includes a dual stage coal pick-up for assuring coal fill of the conveyor system to accurately meter coal therefrom in accordance with the speed of the variable drive motor for driving the conveyor and wherein the system includes an improved sealed discharge manifold means for directing a controlled amount of the compressor discharge air of the gas turbine engine to a plurality of air jets for blasting high pressure air across the coal pump pistons to direct a fluidized powdered coal mixture into a downstream, closely associated fuel nozzle system for a gas turbine engine combustor.
Abstract: An improved method for coating a porous metal laminated structure having air flow holes on the coated side of the structure including in part, the steps of roughening an exposed surface of the porous laminated material and thereafter spraying a bond layer on the roughened surface at an angle selected to coat it with a thin bond coat layer while depositing only a limited amount of the bond coat material internally of the air flow holes and thereafter spray coating the bond coated surface with a top ceramic coat of heat resistant composition and characterized by requiring a bond coat for adherence to the porous metal laminated material and wherein the top ceramic coat spray angle is inclined opposite to that of the spray angle of deposition of the bond coat material to prevent deposition of the top coat on bond material internally of the air flow holes so as to prevent bonding of the ceramic top coat in the air flow holes thereby to minimize restriction of flow through the air flow hole in the exposed surface o
May 1, 1980
Date of Patent:
July 6, 1982
General Motors Corporation
John R. Cavanagh, Kenneth R. Cross, David L. Clingman, Berton Schechter
Abstract: A fuel distribution system for regulating split of fuel flow between a pilot nozzle system and a main nozzle system for a combustor includes a flow network for directing fuel from a main fuel metering valve into an unrestricted line to a small pilot nozzle orifice producing a fine fuel spray pattern at low fuel flow rates and further including a fuel splitter valve interposed between the outlet from the fuel metering valve and a fuel conduit connected to a main fuel nozzle of increased orifice size to atomize higher rates of fuel flow thereto and wherein the fuel splitter valve includes an electrically energizable component that receives a control signal of desired pilot fuel/air ratio generated by a controller in part utilizing a signal of total actual fuel flow and total actual air flow to produce the control signal to control operation of the splitter valve so as to regulate the amount of fuel flow to the main nozzle system in accordance with the control signal thereby to produce a residual flow of fuel to
Abstract: A hybrid dual property radial turbine rotor for a gas turbine engine includes an airfoil shell having a plurality of radially outwardly directed airfoils thereon joined to a continuously circumferentially formed inner periphery including a constant diameter axially extending portion and a radially outwardly flared skirt portion thereon into which is fitted a preformed hub plug of dense stress resistant material having an axially extending nose portion thereon with a controlled constant circumference surface throughout its length of a precision dimensioned diameter and further including a conical end thereon with a surface thereon of a slope that is congruent with the slope of the flared skirt portion of the cast metal rotor shell and wherein the slope of the flared skirt portion is configured to optimize the location of the high strength hub material and to achieve optimum blade and hub stress levels.
Abstract: A combination ceramic and metal turbine rotor for use in high temperature gas turbine engines includes a metal rotor disc having a rim with a plurality of circumferentially spaced blade root retention slots therein to receive a plurality of ceramic blades, each including side platform segments thereon and a dovetail configured root slidably received in one of the slots.
Abstract: A diffuser for a centrifugal compressor has an annular array of vanes which is movable to vary the configuration of the diffusing passages between the vanes. Each vane includes suction and pressure surfaces joined at an inlet apex and divergent therefrom to form a wedge-shaped control surface between fixed, spaced parallel side walls of the diffuser and pivoted about the apex for varying flow area through the diffuser. Each vane has an elastomeric inner portion which is selectively inflatable to expand to either side of said wedge-shaped control surface to sealingly engage the spaced parallel side walls to seal against gas flow between the pressure surface and the suction surface on each of the vanes.
Abstract: A power turbine rotor drive shaft has a flanged end connected to a turbine rotor disc supported by a rotor bearing housing so as to be rotatably supported by a turbine rotor bearing assembly at one end of the shaft and including a second splined end thereon coupled to a shaft extension supported at one portion thereof by a roller bearing shaft assembly and wherein the shaft has a predetermined fundamental bending vibration mode between the rotor bearing assembly and the shaft bearing assembly and wherein an insert sleeve is shrunk-fit within an inside diameter of the shaft to stiffen the shaft so as to increase the fundamental bending vibration mode of the resultant composite shaft without excessively increasing the weight of the composite shaft.
Abstract: A gas turbine engine combustor has a porous wall structure for directing coolant from a compressed air plenum into a combustion chamber to cool its inner surface; an outer lamina has a first hole pattern therein and an inner lamina diffusion bonded to the outer lamina has a second hole pattern offset from the first hole pattern to direct air from the air plenum in cross-flow relationship across internal walls to cool the outer and inner lamina and the outer lamina has a plurality of relief notches formed part way through its depth which are responsive to thermal gradients across the porous wall structure to break the outer lamina into a plurality of separated shingles thereby to prevent excessive stress formation in the porous wall structure; the inner lamina including flow control means to maintain a regulated flow of coolant from an inlet air plenum to the combustion chamber irrespective of the number of relief notches broken during operation of the gas turbine engine.
Abstract: A turbine vane adjustment assembly for calibrating the nozzle/throat width dimension between adjacent adjustable vanes in a nozzle vane ring assembly and for producing conjoint rotation of the individual vane following their calibration includes a vane stem that extends outwardly of a turbine case and further includes a motion converting sleeve in surrounding relationship thereto and coacting means between the sleeve and the vane stem that concurrently rotates both the sleeve and the stem and also provides relative axial movement of the sleeve with respect to the vane stem; the adjustment assembly further includes an actuator arm for rotating each of the vanes and means for connecting the actuator arm to the sleeve to cause angular positioning of the actuator arm to be directly transmitted to each of the vanes following calibration thereof.
Abstract: A transpiration air cooled combustor for use with gas turbine engines includes an annular wall of laminated readily deformable metal having plural layers of diffusion bonded material in a combustor wall with inner and outer surfaces; each of the inner and outer surfaces has pores formed therein by a process such as photoetching to provide numerous inlets on the outer surface of the combustor wall for directing cooling air through the wall to a plurality of outlets in the inner surface for flow of cooling air across the inner surface; and wherein at least two surfaces of the layers includes a plurality of continuously formed curvilinear grooves communicating with the inlets and outlets and also intersecting one another to form crossover passages between the grooves for communicating the inlets and outlets and wherein the curved grooves serve to produce minimal surface distortion and stretch marks across curvilinear portions of the outer wall portion of the combustor assembly to prevent formation tears therein
Abstract: A combustor assembly for an automotive gas turbine engine includes a continuously ignited, pilot flame tube supported on a combustor dome immediately downstream of a prevaporization prechamber with a fuel and air swirler. The pilot flame tube has an air swirler and fuel nozzle supported on an interior bulkhead and is associated with a fuel system that maintains a shielded pilot flame to prevent flame-out of flammable air/fuel mixtures in the main reaction chamber of the combustor; the fuel system supplies greater fuel to the pilot flame tube at engine fuel start and stop to produce an extended flame plume that extends into the reaction chamber to burn residuum of fuel when the air/fuel ratio in the main reaction chamber mixture is below the flammability limit of the fuel.
Abstract: A variable geometry gas turbine has an array of ceramic composition vanes positioned by an actuating ring coupled through a plurality of circumferentially spaced turbine vane levers to the outer end of a metallic vane drive shaft at each of the ceramic vanes. Each of the ceramic vanes has an end slot of bow tie configuration including flared end segments and a center slot therebetween. Each of the vane drive shafts has a cross head with ends thereof spaced with respect to the sides of the end slot to define clearance for free expansion of the cross head with respect to the vane and the cross head being configured to uniformly distribute drive loads across bearing surfaces of the vane slot.
Abstract: An automotive single shaft gas turbine engine has a monorotor with a plurality of radial flow compressor blades thereon discharging compressed air to a recuperator for transferring heat from engine exhaust to the inlet combustion air to a combustor which produces motive fluid directed across a plurality of radial inflow turbine vanes on the monorotor and wherein the automotive gas turbine engine is further associated with an exhaust flow system including the regenerator, a series connected intercooler and a secondary compressor to produce a subatmospheric pressure source in the engine gas cycle to improve the thermal efficiency of the engine cycle and to further define a vacuum source for operating automotive accessories; and to provide a heat source at subatmospheric pressure for passenger compartment heater operation. The subatmospheric source is connected to the secondary compressor which is operative to compress turbine exhaust gas back to one atmosphere of pressure for discharge to the environment.
Abstract: An improved coal/air dispersion nozzle introduces fuel into the combustion chamber of a gas turbine engine as a finely atomized, dispersed spray for a uniform combustion. The nozzle has an inlet that receives finely powdered coal from a coal transport or coal/air fluidizer system and a scroll swirl generator is included within the nozzle to swirl a fluidized coal/air mixture supplied to the inlet of the nozzle. The scroll is in the form of a thin, flat metal sheet insert, twisted along its length, and configured to prevent build-up of coal particles within the nozzle prior to ejection from its outlet. Airblast air jets are included along the length of the nozzle body to assist in the discharge of the fluidized coal from the nozzle outlet and an angular pintle tip overlies the outlet to redirect coal/air mixture through a desired fluidized coal spray angle.