Abstract: A compressor case structure capable of enhanced active clearance control within the structure is disclosed. Various construction details which enable the discharge of cooling air against the case and which minimize thermal distortion of the case are developed. The concepts are applied to a longitudinally split compressor case and include an external bleed manifold or circular cross section which extends across the longitudinal split in the case. Cooling air is dischargeable beneath the manifold to cool the case structure.

Abstract: Apparatus for casting directionally solidified articles is disclosed. Concepts for obtaining a desired temperature profile in an induction furnace are discussed.An induction furnace 10 has increased heating capacity at the withdrawal end 32 of the susceptor 28. A hot zone baffle 42 is disposed at the withdrawal end to inhibit the radiation of heat energy from the hot zone 12. A plurality of grooves 34 are formed about the interior of the susceptor at the withdrawal end to inhibit the conduction of heat energy out of the susceptor. A preferred thermal profile in the operating furnace with a peak temperature in close proximity to the withdrawal end results.

Abstract: Methods for applying grit containing abrasive coatings by plasma spray techniques are disclosed. Various concepts for obtaining good adherability of the coating to an underlying substrate and for maintaining angularity of the grit particles are discussed. The concepts employ simultaneous contact of the grit particles with matrix material at the surface of the substrate to be coated. In coating narrow substrates, the substrate is offset from the axis of the plasma stream discharging from the plasma gun.

Abstract: An ejector for pumping a low pressure, supersonic driven stream to a high pressure is disclosed. Effective pressure recovery in a relatively short axial length is sought.The low pressure driven stream is flowed at supersonic velocities into the ejector. A high energy driving stream is flowed laterally of the driven stream at a supersonic velocity greater than the supersonic velocity of the driven stream and a static pressure above the static pressure of the driven stream to cause compression of the driven stream at supersonic velocities.

Abstract: Methods and apparatus for manufacturing rapidly cooled powder particles is disclosed. Concepts discussed include both convection cooling and conduction cooling of molten material from which the particles are fabricated.By one effective technique of the present invention, seed particles are dropped across the path of a molten droplet stream causing impact and solidification of the molten droplets on the seed particles. Particles of increased size which are formed of conductively quenched material result.

Abstract: A combustion chamber of the type employing staged combustion principles is disclosed. Effective control of undesirable pollutants is sought over a wide range of operating power levels. A specific objective is to separate staged combustion zones without the penetration of structural apparatus into the chamber. Single site fuel injection is desired.Primary fuel premixing tubes (34) and secondary fuel premixing tubes (38) terminate at the front wall (32) of the combustion chamber (30). The primary fuel premixing tubes have highly angled discharge swirlers at the downstream ends thereof. The highly angled swirlers (66) cause the fuel/air mixture emanating therefrom to burn in close proximity to the front wall. The secondary fuel premixing tubes have lowly angled discharge swirlers, or no swirlers at all, so as to cause the effluent therefrom to penetrate the region at which primary combustion is taking place without significantly influencing the fuel/air ratio at the primary combustion site (P).

Abstract: Methods and apparatus for manufacturng rapidly cooled powder particles is disclosed. Concepts discussed include both convection cooling and conduction cooling of molten material from which the particles are fabricated.By one effective technique of the present invention, seed particles are dropped across the path of a molten droplet stream causing impact and solidification of the molten droplets on the seed particles. Particles of increased size which are formed of conductively quenched material result.

Abstract: Apparatus for impeding the leakage of a fluid medium between the rotating and stationary components of a machine is disclosed. Disposed between the rotating and stationary components is a labyrinth seal including at least two throttle apertures to restrict the flow of the fluid medium across the seal. In one embodiment flow turning means direct fluid flowing from the first aperture into confronting relationship with flow approaching the second aperture.

Abstract: Effective damping of blade vibratory energy is sought by the apparatus described herein. The concepts relate specifically to what is known as blade to blade damping as is distinguished from blade to ground damping.The dampers employed have a "T" shaped cross section geometry and are designed to extend circumferentially on an engine rotor between the platform sections of each pair of rotor blades. The dampers are of extreme light weight such that the slipload forces required to generate sliding contact between the damper and the blade platforms is low.

Abstract: The present invention provides an improved sideplate of the type adhered to the side of a rotor disk for the retention of rotor blades and for blocking the leakage of working medium gases across the rotor disk. The elimination of retaining bolts and rivets is sought.In one effective embodiment of the present invention, the sideplate is adhered to the disk at a bayonet type joint. The sideplate is elastically deformable to enable assembly of the sideplate onto the disk with abutting surfaces of the disk and sideplate in interference engagement at release. The side surface of the disk is tapered in cross section geometry to accommodate deformation of the sideplate.

Abstract: The present invention provides apparatus for precisely distributing a liquid coolant or lubricant about the interior of a rotary machine. Distribution in known quantity is sought over a wide range of shaft speeds.In one embodiment the apparatus of the invention is employed to distribute oil in various quantities to bearings and splines within a clutch assembly. Lubricating oil is sprayed from a stationary nozzle into the interior of a rotating shaft. An insert at the interior of the shaft has a plurality of longitudinal splits which intercept and collect the oil in proximity to orifices in communication with bearings and splines to which oil distribution is desired.

Abstract: A method for manufacturing sandwich panels of the type in which a pair of facing sheets 12 are separated by a multiplicity of pins 14 is disclosed. Concepts and techniques for fabricating the structure in a leachable matrix are discussed. Selective roll bonding and cutting are employed to form pins of accurate dimension contour and spacing.

Abstract: The present invention provides methods and apparatus improving the dimensional accuracy of forged components. Uniformity of like component details is sought and a specific object is to provide a die package for forming closely toleranced appendages integrally with a central disk structure from which the appendages extend. In one effective embodiment incorporating concepts of the present invention, the forging dies include a stationary die and a movable die comprising at least two separately movable elements which are mounted on a common axis with the stationary die. A plurality of arcuate die segments are adjacently placed in cylindrical array about the stationary and movable dies. The arcuate die segments form cavities of the inverse geometry of the appendages to be formed and in at least one embodiment are interlocked to prevent tilting of the segments in the die package.

Abstract: A fixture capable of accurately manipulating a workpiece through a circular arc is provided. Various concepts useful in the formation of a cylindrical surface on the workpiece are developed. One fixture described includes a pair of opposing spherical surfaces which are restricted in degree of movement by a key extending from one surface into a slot in the opposing surface.

Abstract: A durable, outer air seal structure capable of long term, reliable service in a gas turbine engine environment is disclosed. Various construction details which enable the incorporation of high temperature tolerant ceramic materials into the outer air seal structure are developed. The structure is built around a porous, low modulus pad of metallic material which is disposed between the ceramic material and a substrate of solid metallic material. The ceramic material is applied to a preferred density at which the physical properties of modulus of elasticity (E), mean tensile strength (T), coefficient of thermal expansion (.alpha.) and thermal conductivity (K) impart good thermal shock resistance, erosion resistance and abradability characteristics to the seal structure.

Abstract: A turbofan configuration for a gas turbine engine is disclosed. Various construction details which improve engine performance by supercharging working medium gases to the engine core are discussed. Engines configured in accordance with the present invention include an island splitter which is disposed across the fan flow path. The island splitter is spaced apart from the core engine case. A supercharging, compression stage is driven commonly with the fan stage and extends outwardly into proximity with the core case.

Abstract: The present invention provides improved concepts for making judicious use of vane cooling air without introducing mechanical stresses or differential growth induced deformation into the structure. Maintenance of an adequate pressure differential across a tubular insert without inhibiting thermal growth is sought and a specific object is to closely control the leakage of cooling air between a slidable end of the insert and the interior of the vane.In one effective embodiment incorporating concepts of the present invention, a tubular insert 26 is affixed to the vane at one end 32 thereof and is free to slide along the interior surface 28 of the vane at the other end 34 thereof. Leakage of cooling air between the insert and the vane is controlled by closely toleranced correspondence of a closure plate 36 at the slidable end of the insert with a cooling air supply tube 38 which penetrates the closure tube.

Abstract: An object of the invention is to prevent the leakage of working medium gases across a rotor stage beneath the platforms of the rotor blades.A rotor assembly structure in which the concepts of the present invention are employable is disclosed. Techniques for blocking the leakage of working medium gases around a rotor stage beneath the platforms of the blades are discussed.

Abstract: A rotor blade design capable of long term reliable operation in a high temperature environment is disclosed. Various cooling concepts adapted to preserve the mechanical properties of the blade material are developed. A cooling system for the blade is built around a multiple supply construction in which cooling medium from a first supply is mixed internally of the blade with cooling medium from a second supply.

Abstract: Apparatus for towing and hoisting vehicles to be serviced is described. Concepts and techniques for enabling effective capability under varied conditions of terrain and footing are discussed. Specific apparatus described combines an extendable boom which is rotatable about a center post and lateral stabilizers on the truck afterbody. Top and bottom rollers on the base tube of the boom guide the outreach arm of the boom to a retracted position around a hydraulic actuator within the base tube. Side mounted actuators rotate the boom about the center post.