Abstract: In a gas turbine including a compressor having a bore and a rotor comprised of multiple stages extending between a first stage at a forward end of the compressor and a last stage at an aft end of the compressor, each stage including a rotor disk having a peripheral rim and multiple blades secured to the peripheral rim, a combustion system comprising a plurality of combustors utilizing discharge air from the compressor for combustion, and multiple turbine stages driven by combustion gases from the combustion system, the improvement comprising means for supplying cooling air at least to a peripheral rim of the last stage of the compressor.

Abstract: A gas turbine engine component includes a wall portion with at least one compound cooling hole formed therein between an external surface of the component and an interior plenum. The at least one compound cooling hole includes a non-circular diffuser opening formed by a laser beam with a non-circular cross-sectional area, and a channel with a substantially circular cross-section connecting the diffuser opening and the interior plenum. The channel is also formed by the non-circular laser beam in the same laser drilling operation as the diffuser opening. The cooling hole further includes a transition point at which the compound hole begins to convert from a substantially non-circular cross-section to a substantially circular cross-section. The location of the transition point is controlled by positioning a focal point of the non-circular laser beam to undershoot the external surface of the component by a predetermined distance.

Abstract: A thermal barrier coating adapted to be formed on an article subjected to a hostile thermal environment while subjected to erosion by particles and debris, as is the case with turbine, combustor and augmentor components of a gas turbine engine. The thermal barrier coating is composed of a metallic bond layer deposited on the surface of the article, a ceramic layer overlaying the bond layer, and an erosion-resistant composition dispersed within or overlaying the ceramic layer. The bond layer serves to tenaciously adhere the thermal insulating ceramic layer to the article, while the erosion-resistant composition renders the ceramic layer more resistant to erosion. The erosion-resistant composition is either alumina (Al.sub.2 O.sub.3) or silicon carbide (SiC), while a preferred ceramic layer is yttria-stabilized zirconia (YSZ) deposited by a physical vapor deposition technique to have a columnar grain structure.

Abstract: A circuit breaker position switch unit is mounted to the sidewall of an industrial type draw-out circuit breaker enclosure to indicate whether or not the circuit breaker is electrically-connected within the enclosure. A time dwell is provided by the structural arrangement of the switch actuator plate with respect to the position indicator bracket. The position switch finds application where a number of circuit breakers communicate with a central processor control unit.

Abstract: A lamp is provided with a mounting arrangement for achieving a precise alignment. The lamp includes a double-ended light source, a metal strap clamping one end of the light source at two locations, and a plastic base having an internal opening wherein the metal strap is engaged. The metal strap includes two clamping members between which the light source is clamped and a cap member attached to the clamping members. The cap member has tabs adapted for engaging the internal opening of the plastic base and gimbaling the light source to align the light source with respect to the plastic base. The clamping members are joined together at a point between the to clamping locations such that a spring force clamps the light source. The clamping members are also oriented at an angle of about 45 degrees from vertical to better withstand both vertical and horizontal loads.

Abstract: A GTO gate driver circuit includes a GTO; a MOS gate driver; a turn-on rectifier for receiving power from a high voltage isolation transformer; a turn-on capacitor coupled in parallel with the turn-on rectifier; and a turn-on MOSFET having a drain coupled to a first side of the turn-on capacitor, a gate coupled to the MOS gate driver, and a source coupled to a gate of the GTO. In one embodiment the circuit includes a turn-off rectifier coupled to the turn-on rectifier; a turn-off capacitor coupled in parallel to the turn-off rectifier with a cathode of the GTO being coupled to a second side of the turn-on capacitor and a first side of the turn-off capacitor; and a turn-off MCT having a gate coupled to the MOS gate driver, an anode coupled to the source of the MOSFET and a cathode coupled to a second side of the turn-off capacitor.

Abstract: A heat shield for a gas turbine engine combustor of the type composed of multiple annular stages. The heat shield is particularly adapted for use in a middle stage disposed between radially inward and outward stages of a multistage combustor, and configured to form centerbodies that isolate the middle stage from the other stages of the combustor. The heat shield is composed of an annular array of single crystal superalloy segments. To achieve acceptable levels of durability for the superalloy segments, their primary and secondary crystal orientations are controlled to achieve a balance between the ability to withstand thermally-induced stresses and those stresses induced by high levels of acoustic energy, particularly those high levels attained as a result of a combustor operating with lean fuel/air ratios.

Abstract: Systems and methods for controlling a draft inducer for use with a furnace. The draft inducer includes a fan for inducing a draft in the furnace combustion chamber that causes a pressure drop across a heat exchanger assembly for moving exhaust combustion chamber gases. The heat exchanger assembly has a plurality of heat exchanger elements which determine furnace capacity wherein the pressure drop across the heat exchanger assembly is affected by the furnace capacity. A motor drives the fan in response to a motor control signal and a memory stores information defining a relationship between motor speed, motor torque and parameters defining motor operation. A processor determines the speed and torque of the motor and retrieves from the memory the parameters corresponding to the determined motor speed and motor torque. The processor is responsive to the retrieved parameters for defining at least one set of speed/torque curves corresponding to a desired pressure drop across the heat exchanger assembly.

Abstract: A system for the recycling of overspray powder during spray forming is provided. The system involves providing a refining vessel to contain an electroslag refining layer floating on a layer of molten refined metal. An ingot of unrefined metal is lowered into the vessel into contact with the molten electroslag layer. A current is passed through the slag layer to the ingot to cause surface melting at the interface between the ingot and the electroslag layer. As the ingot is surface melted at its point of contact with the slag, droplets of the unrefined metal are formed and these droplets pass down through the slag and are collected in a body of molten refined metal beneath the slag. The refined metal is held within a cold hearth. At the bottom of the cold hearth, a cold finger orifice permits the withdrawal of refined metal from the cold hearth apparatus. The refined metal passes from the cold finger orifice as a stream.

Abstract: A solid state method of converting a polycrystalline ceramic body to a single crystal body includes the steps of doping the polycrystalline ceramic material with a conversion-enhancing dopant and then heating the polycrystalline body at a selected temperature for a selected time sufficient to convert the polycrystalline body to a single crystal. The selected temperature is less than the melting temperature of the polycrystalline material and greater than about one-half the melting temperature of the material. In the conversion of polycrystalline alumina to single crystal alumina (sapphire), examples of conversion-enhancing dopants include cations having a +3 valence, such as chromium, gallium, and titanium.

Abstract: Insect debris is removed from or prevented from adhering to insect impingement areas of an aircraft, particularly on an inlet cowl of an engine, by heating the area to 180.degree.-500.degree. C. An apparatus comprising a means to bring hot air from the aircraft engine to a plenum contiguous to the insect impingement area provides for the heating of the insect impingement areas to the required temperatures. The plenum can include at least one tube with a plurality of holes contained in a cavity within the inlet cowl. It can also include an envelope with a plurality of holes on its surface contained in a cavity within the inlet cowl.

Abstract: A mounting clip for securing a motor protector to the stator of an electric motor is described. In one embodiment, the mounting clip includes a protector holding region formed by a base portion, a back portion, arm portions, and a retaining member. The protector is positioned within the protector holding region. The base of the mounting clip seats upon the uppermost, or outermost, lamination of the lamination stack forming the motor stator and includes one or more fingers sized for insertion between adjacent stator winding gaps. The mounting clip is maintained in position by the friction fit between the clip fingers, the stator windings and insulation.

Abstract: Spring latching mechanisms for preventing relative rotation or relative displacement of assembled components during operation of a nuclear reactor. The first type of mechanism prevents rotation of a threaded fastener which fastens a first component to a second component. The fastener has a multiplicity of longitudinal recesses formed on an outer circumferential surface thereof. The spring latching mechanism has a cantilever beam supported at one end by the first component. The other end of the cantilever beam is displaceable between first and second positions as the cantilever beam flexes. An interlocking member connected to the second end of the cantilever beam fits engages one of the longitudinal recesses in the fastener, whereby rotation of the fastener can be blocked. The second type of mechanism positively locates and prevents vibration-induced wear of first and second components assembled with play therebetween.

Abstract: Low viscosity MQ silicone resins as a composition of matter, methods of preparation of same and cosmetic and personal care products comprising said MQ resins.

Abstract: A nuclear reactor including a heat pipe for transferring heat from the reactor pressure vessel to a steam supply vessel is described. More particularly, in one embodiment, the heat pipe includes an evaporator section positioned in the reactor vessel, a condenser section positioned in the steam supply vessel, and an adiabatic section extending between and in flow communication with the evaporator section and the condenser section. The adiabatic section of the heat pipe includes a substantially cylindrical outer sleeve and a substantially cylindrical inner sleeve. An annulus region is formed between the inner and outer sleeves and the annulus region is in flow communication with the steam supply vessel. An insulating layer covers an inner wall of the outer sleeve. A substantially annular wick member is positioned adjacent an inner wall of the inner sleeve, and a steam path is defined by an inner face of the wick member.

Abstract: A gas turbine engine of the type generating a hot gas stream and a fan stream includes a mixer having upstream and downstream portions which define first and second chutes for efficiently mixing the streams prior to discharge through an engine nozzle. Means are provided to selectively communicate the downstream chutes with alternate ones of the upstream chutes to cool the downstream mixer portion and reduce the infrared radiation emissions from the nozzle.

Abstract: A bond-coated substrate is protected with an alpha alumina layer. The alpha alumina layer may be deposited as a relatively thick layer directly onto the bond-coated substrate. In this embodiment, no further ceramic layer overlies the alpha alumina layer. Other ceramics may be mixed into the alpha alumina layer, however. In another embodiment, a layer of a ceramic other than alpha alumina is deposited over the bond-coated substrate, and an alpha alumina layer is deposited over the ceramic layer.

Abstract: A bonded assembly which includes a heating element in thermal contact with the adhesive component of the bonded assembly, such that the heating element can serve to thermally degrade the adhesive so as to allow disassembly, repair and servicing of the bonded assembly. The invention is particular suited for use in an abradable shroud assembly used in the fan section of a turbomachine, such as a high bypass turbofan engine. The abradable shroud assembly includes an abradable material bonded to the fan casing with an adhesive material having a known thermal degradation temperature. Placed in thermal contact with the adhesive layer is a heating element, such that the heating element is capable of heating the adhesive to a temperature above its thermal degradation temperature.

Abstract: A lenticular lens containing a multiplicity of multi-sided lenticules useful with reflector lamps provides improved light distribution by having the lenticules oriented to avoid parallelism with a projected light image and distributed in a plurality of zones or bands concentric about said optical center. The size and light-spreading ability of the lenticules in each zone is selected to provide the desired light distribution. Parallelism is avoided by having the lenticules arrayed in a plurality of wedge-shaped sections circumferentially arranged in a circle around the optical center of the lens and extending through the zones with the lenticules in each section arrayed in a uniform, close-packed hexagonal array of parallel rows with the longitudinal axis of one of the rows being radially aligned with respect to the optical center of the lens, so that none of the sides of the lenticules are parallel to the light source image projected off the reflector.

Abstract: A method is provided for the manufacture of precision electronic components such as resistors, inductors, and capacitors on a polymer or ceramic surface. The electronic components can be deposited and trimmed to precise or matched values without having precise depositions of all of the pre-patterned materials. Thin film electronic components are deposited on a surface, parameter values are measured or estimated, a correction offset file is generated, and the components are trimmed using adaptive lithography to a very close tolerance. A computer program can be used to enable the adjustment of electronic components by techniques such as changing the physical length of an inductor coil or resistor lead, or by changing a capacitor plate area.