Abstract: An exemplary apparatus for determining the thicknesses of individual layers in a multilayer article comprises an ultrasonic transducer coupled to the multilayer article with a buffer rod of similar acoustic properties, a pulser-receiver-amplifier which generates ultrasonic waves to produce discernible, time resolved pulse echoes, a digitizing oscilloscope which may be used to view the received pulse echoes, and a computer for controlling data acquisition and analysis.

Abstract: The instant invention is directed in general to combustors for gas turbines and, more specifically, to a hybrid can-annular combustor for axial staging in low NOx Combustion. In a preferred embodiment, the instant invention uses premixing stages at different axial positions to carry out axial staging of the heat release for increased operability, where the combustor has a first premixing means for injecting a fuel-air mixture into a can-type configuration for providing the advantages of a can-type combustor for low-load and/or low-temperature conditions and a second premixing means for injecting a fuel-air mixture into an annular-type configuration for providing the advantages of an annular-type combustor for high load and/or high temperature conditions.

Abstract: A turbine blade including an airfoil section having contoured surface geometries between the consecutive ribs or turbulators on the leading edge passage walls is described. The contoured surface geometries increase the overall heat transfer surface area between adjacent ribs as compared to the heat transfer surface area of a smooth inter-rib wall. The contoured surface geometries do not, however, change the overall serpentine passage geometry or the large scale flow characteristics of the turbulated cooling passageways. The contoured surface geometries may have many different geometries (e.g., triangular, conical, semi-cylindrical, cylindrical columns or indentations in the side wall such as semi-circular dimples).

Abstract: A rotor and stator assembly having a rotor and a stator with opposing surfaces defining an air bearing and an air dam of an aspirating face seal. In a first embodiment, the air bearing and the air dam are axially offset. In a second embodiment, the rotor has an axially extending protuberance located radially between the air bearing and the air dam. The axial offset and the protuberance each act to divert the air flow (e.g., compressed gas or combustion gases in a gas turbine or steam in a steam turbine) in a direction transverse to the air flow direction through the air bearing and the air dam, thus isolating the air flows from the air bearing and the air dam which improves seal performance.

Abstract: A seal assembly and a rotary machine, such as a steam turbine, containing the seal assembly. A casing circumferentially surrounds a rotor and includes a circumferential channel open to the rotor. Seal segments are circumferentially arrayed in the channel and are movable between radially inward and outward positions. Circumferentially adjacent seal segments have circumferentially opposing surface grooves. A resilient and imperforate member is engaged in the grooves of circumferentially-adjacent seal segments circumferentially urging apart such segments and providing sealing between such segments.

Abstract: A capacitor is fabricated on a base surface by applying a first pattern of electrical conductors (a first capacitor plate) over the base surface with an outer surface of the first pattern of electrical conductors including molybdenum. A first hard portion of a capacitor dielectric layer including amorphous hydrogenated carbon is deposited over the first capacitor plate and the base surface, a soft portion of the capacitor dielectric layer is deposited over the first hard portion, and a second hard portion of the capacitor dielectric layer is deposited over the soft portion. The deposition of the soft portion occurs at a lower bias voltage than the deposition of the first and second hard portions. A second pattern of electrical conductors (a second capacitor plate) is applied over the capacitor dielectric layer which is then patterned.

Abstract: A combustor liner includes an inner layer for facing combustion gases, and an opposite outer layer for facing a cooling fluid. The outer layer has a greater coefficient of thermal conductivity than the inner layer for reducing temperature gradients in the liner. In a preferred embodiment, the outer layer significantly reduces temperature gradients in the liner which are caused by the varying cooling ability of impingement cooling air jets for more uniformly cooling the combustor liner and reducing the maximum temperature thereof.

Abstract: A brush seal which, among other applications, may be used for sealing a steam leakage gap between a steam turbine rotor and a steam turbine casing. A brush seal backing plate has a surface which includes adjacent first and second areas. First and second bristle packets contact and generally cover, respectively, the first and second areas. A first anti-hysteresis plate is positioned between and contacts the first and second bristle packets, is aligned generally perpendicular to the backing plate, and is proximate and generally spaced apart from the backing plate. The anti-hysteresis plate restores the bristles which would otherwise become set in a non-sealing position against the backing plate because of transient events such as thermal differential growth or relative movement of the rotor and casing.

Abstract: A SiC MOSFET having a self-aligned gate structure is fabricated upon a monocrystalline substrate layer, such as a p type conductivity .alpha.6H silicon carbide (SiC) substrate. An SiC n+ type conductivity layer is epitaxially grown on the substrate layer. A steep-walled groove is etched through the n+ SiC layer and partially into the p SiC layer at a location on the substrate where a MOSFET gate structure is desired. Subsequently, a thin layer of silicon dioxide and a layer of gate metal are successively deposited over the entire structure. The gate metal layer is deposited with sufficient thickness to substantially fill the groove. A layer of photoresist is applied to the entire surface of the gate metal layer. The photoresist and the underlying gate metal are then reactive ion etched down to the oxide layer, leaving gate metal remaining only in the groove.

Abstract: A brush seal which, among other applications, may be used for sealing a steam leakage gap between the shrouded free end of steam-turbine buckets (blades) of a steam-turbine rotor and a circumferentially surrounding steam-turbine stator. In a first embodiment, the brush seal includes first and second bristle packets having, respectively, first and second bristles, wherein the second bristles are more abrasive than the first bristles. In a second embodiment, the brush seal includes a bristle packet having bristles which are more abrasive proximate their free ends than not proximate their free ends.

Abstract: This invention is directed in general to a locomotive diesel engine, and more specifically, to a method and apparatus for performance based assessment of a locomotive diesel engine.

Abstract: A probe is configured for measuring color in a sample of material having a refractive index. The probe includes a light source that emits a light beam toward the sample. A color sensor is disposed at an oblique angle with the light source and directed toward a common probe zone for containing the sample. The light source and sensor are optically aligned with a reference plane in the probe zone to effect angles of incidence and reflection relative to the zone having a magnitude substantially equal to Brewster's maximum polarization angle for the refractive index of the sample, for measuring interior color of the sample.

Abstract: A motor assembly, such as an evaporator fan for a refrigerator, has a motor, first and second mounting bracket segments, and monolithic and elastomeric first and second grommets. The motor housing has opposingly protruding first and second end bosses. Each grommet includes inner and outer ring portions joined together by spaced-apart and generally-radially-extending spoke portions. The inner ring portion is positioned on the corresponding end boss. The outer ring portion has a hub and a circumferential flange radially projecting form the hub. Each mounting bracket segment has an opening, wherein the hub is positioned in the corresponding opening and wherein the circumferential flange longitudinally abuts the corresponding mounting bracket segment.

Abstract: For providing multiple-conductor circuit interconnections where there is a lack of precise dimensional control, as in manufacturing flexible printed circuits used to make high density electrical interconnections between ultrasonic transducer elements and the probe cable in a medical ultrasound probe, connection pads are formed in fanout arrays, with the longitudinal axes of individual pads extending along radial lines from the center of a circle. The fanout arrays are formed within generally trapezoidal areas, each having two parallel opposite sides extending along respective parallel chords to accommodate significant variation in dimensions of the respective substrates being connected. Multiple-row connection pad arrays may be provided, each with a plurality of fanout arrays of connection pads that may be parallel to each other and positioned at respectively different distances from the center of the circle, or may be arranged around, and positioned at equal distances from, the center of the circle.

Abstract: A laser resonator includes a laser medium having opposite end faces inclined at Brewster's angle and disposed in optical alignment between spaced-apart and tilted first and second optical elements. A method for adjusting the optical alignment includes pumping the laser medium to produce a laser beam, and adjusting separation spacing between the two optical elements. Tilt of at least one of the optical elements is adjusted in response to any observed change in beam cross-sectional size. In an additional embodiment, the laser medium is initially positioned at about equal spacings between the first and second elements. Position of the laser medium is then adjusted, at a constant value of the separation spacing, to within a position range selected for a specific value of a ratio of intracavity peak power of circulation of the laser beam and a critical power for self-focusing to effect discrimination of mode-locked operation over continuous wave operation.

Abstract: An ultrasound imaging system uses a synthetic transmit aperture method with prefocused subapertures. The transmit aperture is divided into several subapertures. Transmission is done sequentially on each subaperture while receiving on the full aperture. The received data sets are then combined using the appropriate delays. In this way the focusing performance of a composite focusing system using a number of focal zones equal to the square of the number of subapertures is achieved. The gain is an increase in the frame rate which is also equal to the number of subapertures used.

Abstract: A reinforced motor for reducing amplitude of operational vibrations includes a stator having an open end, a rotor disposed through and centrally of the stator and having at least one end, an end shield mounted to the open end of the stator and having an outer surface and rotatably supporting the rotor at the one end thereof, and an elongated stiffening member attached to or formed on the outer surface of the end shield so as to increase stiffness and reduce bending of the end shield and thereby reduce amplitude of operational vibrations produced by rotation of the rotor relative to the stator. A peripheral portion of the end shield forms an opening for receiving a switch housing. The stiffening member is attached on the outer surface of the end shield adjacent to the switch housing opening.

Abstract: A low NOx combustor and method improve dynamic stability of a combustion flame fed by a fuel and air mixture. The combustor includes a chamber having a dome at one end thereof to which are joined a plurality of premixers. Each premixer includes a duct with a swirler therein for swirling air, and a plurality of fuel injectors for injecting fuel into the swirled air for flow into the combustion chamber to generate a combustion flame therein. The fuel injectors are axially staged at different axial distances from the dome to uncouple the fuel from combustion to reduce dynamic pressure amplitude of the combustion flame.

Abstract: A brush seal which, among other applications, may be used for sealing a steam leakage gap between the shrouded free end of steam-turbine buckets of a steam-turbine rotor and a circumferentially surrounding steam-turbine stator. In a first embodiment, an unflexed brush seal includes bristles having a generally straight first portion secured to a backing plate and a coextensive and generally straight second portion with a free end. The second portion makes a greater angle, than that of the first portion, with respect to a directed reference line. In a second embodiment, the first and second portions are curved, wherein a tangent line to the second portion makes a greater angle than a tangent line to the first portion.

Abstract: A sample having a coined line is analyzed by traversing a light spot across the sample, and then analyzing both specular and diffuse light reflected from the sample to spatially resolve the coined line. An analyzer includes a holder for supporting the sample which is illuminated by projecting the light spot onto the sample. Light collectors receive the specular and diffuse light from the sample at the spot. The received light is analyzed to detect changes therein indicative of the coined line.