Abstract: Apparatus and method for starting a gas turbine engine is shown wherein the combustion chamber has a fixed geometry providing a high throughput velocity to prevent flashback during normal operation of the engine. Thus, there is provided a flame holding zone out of the main flow path through the chamber that exhausts into the chamber upstream of a catalytic reactor element to preheat the catalyst to a sufficiently high temperature for continuous auto-combustion therein prior to the rotor of the engine attaining running speed. After running speed the combustion in the flame holding zone is extinguished and the velocity of the fuel/air mixture in the main flow path through the chamber is sufficient to maintain the combustion within the catalytic element for the continuous running of the engine without any flashback.

Abstract: The present invention provides an assembly for mounting a row of ceramic rotor blades in the metal rotor disc of a gas turbine engine. The major components of the assembly comprise a well known ferritic metal rotor disc in which is mounted, in a conventional fir-tree root configuration, a plurality of high temperature metal alloy or super alloy intermediate members forming an annular array thereof and defining "dog-bone" shaped axial grooves in the annular face for receipt of a complementary "dog-bone" or single serration root of a ceramic blade for mounting an annular array of ceramic blades. The root shank portion and the air foil portion of the blade are separated by a platform and centrifugal-force pins are inserted between adjacent platforms to fix the blade against low frequency vibration and to seal the gap therebetween against leakage of the motive fluid into the root area.

Abstract: A cooled vane for a gas turbine engine in which the coolant channels have an arcuate component, convex outwardly towards the surface of the vane to establish centrifugal force in the coolant flowing therethrough and thereby induce a secondary flow to the coolant, promote mixing and reduce the outer boundary layer of the coolant to enhance the heat transfer characteristics to the coolant and thereby more efficiently maintain the vane within acceptable temperature limitations.

Abstract: A combustor for a gas turbine is shown having a catalytic reactor element to promote low temperature combustion of the fuel. An air-fuel premix chamber is provided in the upstream end of the combustor arrangement to produce a mixture which is substantially uniform throughout a plane transverse to the direction of flow of the mixture just prior to the catalytic element. The premix chamber comprises a short cylindrical member of less diameter than the shell of the combustor and closed at the upstream end, with the opposite end discharging directly to the catalytic element. The upstream portion of the walls of the cylinder contain apertures so that the air and fuel introduced into the upstream end of the combustor must flow axially into the annular space between the shell and the chamber, then the flow is abruptly changed to a somewhat radial component to enter the apertures and then the flow is again abruptly changed to an axial direction to enter the catalytic reactor.

Abstract: A stator vane assembly is provided, particularly for the first row of stationary vanes of a gas turbine, utilizing ceramic vanes. Each individual vane assembly consists of an airfoil vane with a separate end cap at each end for supporting the vane in position. Each vane has an airfoil portion with a tenon portion at each end thereof having a curved surface for engagement in a recess in the adjacent end cap which has a similarly curved surface. The tenons have a different cross-sectional configuration that the airfoil portions of the vane such that the area of contact between the tenons and the end caps is greater than the cross-sectional area of the airfoil portion and is preferably substantially coextensive with the surface of the recess in the end cap. The tenons terminate short of the leading and trailing edges of the airfoil portion so that the tenons are not coextensive with the airfoil in either direction.

Abstract: A unison ring for adjusting the nozzle vanes in a split shaft gas turbine is mounted via a secondary ring attached to and encircling the casing. The secondary ring is mounted so as to accommodate dimensional variations in the housing due to temperature changes without altering the freely movable mounting engagement of the unison ring. The unison ring can thus be easily adjusted regardless of the variations in radial dimension between the housing and the unison ring.

Abstract: The invention comprises sealing structure between a seal plate, a rotor, and a blade, for sealing the root portion of a rotor and blade assembly to provide a sealed chamber adjacent the base of the root into which radially directed passageways in the blade open for transmitting the cooling fluid, delivered to the chamber, through the blade to the tip end thereof to cool the blade. The seal is perfected through a wedging action caused by centrifugal force moving the base or foot of the plate, disposed below the blade root, into sealing engagement with the rotor disk, and an intermediately disposed seal bar extending arcuately just radially outwardly of the radially innermost portion of the root and generally in the vicinity of the innermost loaded root projection with the loaded root providing the axial seal and the sealing bar and seal plate foot providing the radial seals to define a cooling fluid chamber adjacent the base of the root.

Abstract: A two shaft gas turbine engine is shown wherein the power turbine comprises a single stage which is closely coupled to the compressor turbine through an annular transition portion having radially diverging side walls forming an inner and outer shroud. The relatively high velocity of the working fluid is maintained through the transition portion by an array of non-rotating stationary struts. Each strut defines a camber line which at the entry of the strut is angled to receive the working fluid, having a swirl component therein, at a 0.degree. angle of incidence. Further, each strut has a configuration which, in cooperation with the increasing angle of the camber line compensates for the divergence of the shrouds to maintain the flow of the working fluid at a generally undiminished velocity therethrough.

Abstract: An interconnection or crossover construction is provided for interconnecting the combustors of a combustion apparatus such as a gas turbine. The connection between adjacent combustors is made by means of a flexible tube which permits a substantial amount of misalignment between adjacent combustors, and the construction also provides for accommodating thermal expansion and contraction of the parts and for the admission of cooling air.

Abstract: A vane assembly is shown for a relatively short annular transition zone directing the discharge of the working fluid from the compressor turbine to a single stage power turbine in a gas turbine engine. The annular transition zone comprises a plurality of individual arcuate segments having a pair of stationary vanes integrally molded to inner and outer shroud members. A variable vane is disposed immediately downstream of each stationary vane for guiding the working fluid into the power turbine at an optimum angle. The variable vanes are manually adjustable from outside the turbine casing through a linkage and support mechanism that maintains a constant clearance between the variable vane and the shroud members and also accommodates variations in dimensional relationships due to temperature variations. Also, provision is made for centering the axis of the variable vanes to a precise position with respect to the stationary vane to accommodate the buildup of assembly tolerances.

Abstract: A seal is provided between adjacent stationary annular shroud members in a gas turbine. The shroud members have an axially directed gap disposed between their adjoining ends. Each adjoining end of each stationary shroud has a shoulder arrangement which provides support for a seal disposed across the gap. The shoulders on the ends of the shrouds provide restraint against radially inwardly directed dislocation, and a blade ring which supports the shroud members themselves, provides restraint against axial and radially outwardly directed dislocation. The seal prevents escape of hot motive fluid from the generally axially directed working fluid flow path.

Abstract: A catalytic combustor arrangement for use with a gas turbine power plant, has independently regulatable fuel injection elements disposed upstream of a discrete array of passageways disposed between the fuel injection elements and a catalytic reaction member. The centermost fuel injection elements of each combustor may function alone which will permit efficient idling operation of the power plant. The passageways will maintain the flow of fuel and air to only the central portion of each catalytic reactor element thus providing the efficient, low speed, idling, operation of the turbine. As additional fuel injection elements are activated, additional portions of the catalytic reaction member perform the combustion function at the desired level of turbine operation. Thus a wide range of operating conditions of the gas turbine is efficiently permitted with the regulatable fuel injection arrangement therewith.

Abstract: A simplified interstage seal assembly for a turbomachine utilizing an abradable semicircular seal slidably held radially inwardly of a stator shroud by a pair of semicircular seal holders. The seal holders are retained between radially depending flanges of shroud segments, with each holder having a key portion projecting through radial slots in the flanges for guided radial expansion or contraction. The holders, after insertion of the keys in the slots, are spatially separated a predetermined distance and maintained in the separated and engaged position by engagement of a seal ring which is supported in the seal holders, in a track and channel arrangement, with a portion of the seal ring disposed in the space between the opposed seal holders to prevent axial displacement of the seal holders and thereby retain the key portions thereof within the slots of the flange.

Abstract: A catalytic combustor has an array of fuel injectors and air inductor elements, upstream of a catalytic member in the combustor. Each fuel injector and air inductor arrangement is associated with a discrete passageway confining the air/fuel mixture to a portion of and the catalytic member wherein the combustion of the mixture is initiated. Each fuel injector and air inductor arrangement is provided with controls to vary the fuel and air flowing into each passageway, respectively. This permits the variation of combustion intensity within the catalytic element, which in turn permits a regulatable temperature profile at the exit end of the combustor.

Abstract: A slidable seal is disposed in one end of each stationary arcuate shroud segment in a gas turbine. The seal is forced by a spring across a gap between adjacent shroud segments, to abut against an end of an adjacent shroud segment. The slidable seal helps control fluid leakage in both the axial and the radial direction.