Abstract: A method of imparting birefringence in a III-V compound semiconductor for sustaining the non linear optical process of second harmonic generation, a birefringent III-V compound semiconductor, and a product of the process are described.

Abstract: A wing mounted yaw control device is disclosed. The wing mounted yaw control device includes a spoiler hingedly mounted on a first wing surface and a deflector hingedly mounted on a second wing surface. A deployment mechanism is provided to effect simultaneous deployment of the spoiler and deflector. During operation, the spoiler and deflector are selectively deployed in order to impart an unbalanced drag force on one wing, thereby imparting the desired yaw moment to an aircraft in flight.

Abstract: Certain transient events such as hard landings, high g-rate turns, thermal conditions, and high turbulence may cause rubbing events inside the gas turbine that result from the flexure of the engine shafts. In order to prevent permanent damage to the engine or operational interference, brush seals are used such that the tips of the stator blades and the tips of the respective opposing annular brush seals, and the tips of the rotor blades and the tips of the respective opposing annular brush seals define substantial radial clearances that provide gaps that remain open under all regular and normal operating conditions of the gas engine.

Abstract: A high power density alkaline electrochemical capacitor cell includes a pair of titanium nitride powder electrodes fabricated by subjecting titanium hydride powder to a controlled flow of ammonia vapor. A porous separating membrane for containing an electrolyte is attached to a first surface of the pair of powder electrodes. A conductive termination is attached to the second side of each of the powder electrodes. The electrodes have a high surface area and are electrochemically stable in strong alkaline electrolyte. The capacitor cell can be hermetically sealed and is capable of long-term cyclical operation over a wide range of operating temperatures (−55° C. to +100° C.) while providing high-density energy storage.

Abstract: An accurate, low-cost, non-contact strain measuring method and apparatus for measuring strain in low modulus porous materials using optical microscopy are described wherein, in a preferred embodiment of the invention, fluorescent ink reference lines are applied to a surface of a specimen, the specimen is mounted on the stage of an optical microscope having an attached x-y digital micrometer, and a load is applied to the specimen. The surface is viewed using a light source that renders the reference lines visible, and changes in displacement of selected points on the reference lines are measured for each incremental loading. Poisson's ratio may be calculated from the strain measurements in two orthogonal directions.

Abstract: A friction damped turbine blade is disclosed. The turbine blade is formed of segments configured so as to form an assemblage corresponding to the airfoil shaped body. Each of the segments is in slidable contact with an adjacent segment. During turbine operation, the segments rub against one another due to the stresses placed on the blade, imparting frictional damping to the turbine blade.

Abstract: A gas turbine engine structure is described wherein the compressor region and the turbine region of the engine are disposed substantially concentrically of each other between fixed inner and outer casings, with the combustor disposed at one common end of the compressor and turbine, and wherein the rotor components of the engine include one or more rings, bands, housings or casings with the turbine blades and compressor blades mounted respectively on the inner and outer surface thereof, and wherein the compressor and turbine stator components are mounted respectively on the inner surface of the outer casing and the outer surface of the inner casing, or, alternatively, wherein the turbine and compressor stator components are mounted respectively on the inner surface of the outer casing and the outer surface of the inner casing, which structure geometries eliminate much of the weight associated with the disks and interconnecting shafts that characterize conventional engines.

Abstract: A finned heat exchanger is disclosed. The heat exchanger includes a unitary fin array with a multiplicity of fin banks. Each of the fin banks include a plurality of raised, folded fins for heat transfer. The fin banks extend in a transverse direction and are spaced apart in a longitudinal direction. The fin banks are retained within the fin array by looped expansion turns. The fin array is mounted on a dielectric substrate base. A closed flow channel for directing a flow of coolant is created by adding a cap to the substrate base.

Abstract: A programmable automated turbidimeter/colorimeter system for accurately measuring growth among multiple bacterial specimens is described which in a preferred embodiment includes a motor driven rotatable carousel assembly disposed within an aluminum housing, the carousel assembly including a plurality of evenly spaced peripheral holes for receiving a corresponding plurality of disposable culture test tubes, a light source and a light detector disposed in spaced confronting relationship to each other whereby the culture tubes pass therebetween, and a signal amplifier and a recorder for recording optical densities of each specimen as the carousel is continuously rotated. A concentric magnetic shield may be disposed on one side of the carousel for shielding experimental specimens from control specimens in measurements of magnetic effects on the cultures.

Abstract: Multi-layer corrosion resistant polymer composite coatings are described wherein a first coating layer is applied by high velocity high temperature spray, thermal spray, plasma spray, fluidized bed, hot melt or electrostatic spray onto an unprepared, particle embedded or alternatively prepared substrate, and the outer surface of the still warm first layer is roughened by embedding particles therein or the outer surface is roughened mechanically, and a second coating layer is applied thereover. Filler powder may be added to one or both of the layers to substantially match the thermal expansion coefficients of the two layers.

Abstract: A twin spool counter-rotating turbofan gas turbine engine having a counter-rotating fan module integrated with the high pressure compressor and driven by a counter-rotating turbine utilizing only two drive shafts. The two drive shafts are aerodynamically coupled and rotate in opposite directions relative to each other with or without the use of a gearbox. The integration between the fan module and high pressure compressor allows the fan blade rows to operate at the same mechanical speed of the high pressure compressor blade rows. An afterburner module may be added to the present invention to provide thrust augmentation.

Abstract: An aircraft weapons bay acoustic suppression apparatus is disclosed. The apparatus reduces or eliminates acoustic resonance within an open cavity of an aircraft such as a weapons bay of an aircraft in flight. The apparatus includes an oscillatable spoiler plate which is extended into the airstream. At least one shaker is placed in operative engagement with the spoiler plate in order to oscillate the spoiler plate at high frequencies and high amplitudes to seed the shear layer with frequencies which directly complete with the natural frequency of the shear layer vortices. In this way, the damage arising from natural shear layer vortices can reduced or canceled within the weapons bay.

Abstract: A passively cooled electromechanical actuator is disclosed. The passively cooled electromechanical actuator includes a rotor having an output shaft rotatably received within a stator. A pair of inner supports connect the stator to a pair of mounting platforms. The mounting platforms are attached to the inner surfaces of an aircraft wing and are in thermal communication therewith. A pair of closed, capillary tube thermosyphons containing a working fluid are in thermal communication with the stator, the inner supports and the mounting platforms. During operation, the thermosyphons receive heat from the stator and transport it to the mounting platforms whereupon it is convected or radiated to the atmosphere from the aircraft wings. The inner supports have a phase change material received within for providing temporary thermal energy storage during transient conditions.

Abstract: A micro channel heat pipe and method of fabrication are disclosed. The micro channel heat pipe includes a wire cloth wick having micro capillary channels formed by a corrugation extrusion process. The wick is inserted into the heat pipe housing in a shrink fit, enhancing heat transfer. The porous nature of the wire cloth wick permits free passage of the working fluid within both the closed and open micro capillary channels, doubling the number of micro capillary channels available for heat transference.

Abstract: An apparatus for generating high purity oxygen is described which comprises a linear actuator, a dual acting air cylinder, two molecular sieve beds, and valving. The linear actuator drives the air cylinder back and forth, compressing air on both the forward and return stroke. On each stroke, fresh air is compressed into one of the beds, generating oxygen. Simultaneously, the opposite bed exhausts to ambient pressure and the non-compressing side of the cylinder draws in fresh air. The cylinder then reverses, which compresses air into the opposing bed and allows the first bed to exhaust.

Abstract: A twin spool counter-rotating turbofan gas turbine engine having a counter-rotating fan module integrated with the high pressure compressor and driven by a counter-rotating turbine utilizing only two drive shafts. The two drive shafts are aerodynamically coupled and rotate in opposite directions relative to each other with or without the use of a gearbox. The integration between the fan module and high pressure compressor allows the fan blade rows to operate at the same mechanical speed of the high pressure compressor blade rows. An afterburner module may be added to the present invention to provide thrust augmentation.

Abstract: A spark plug system for measuring the thermal profile across the surface of a piston in an operating internal combustion engine in characterizing the combustion process within a combustion chamber of the engine is described that includes a specially constructed spark plug containing a coherent fiber optic bundle and lens system optically connected to a remote sensing thermometer and high-speed triggerable imaging infrared video camera.

Abstract: Corrosion resistant non-polar polymer coatings and method for applying the coatings to substrates is described, wherein a source of non-polar polymer powder is deposited as a coating onto the surface of a substrate by high temperature thermal spray, wherein the non-polar character of the powder and any additives thereto is substantially preserved during the high temperature thermal spray by using a mixture of a non-oxidizing shielding gas or reducing gas, or combination of the two, at one or more locations along the thermal spray to displace or react with ambient oxygen.

Abstract: A differential property sensitive acoustic lens for non-destructive materials evaluation is described which in a preferred embodiment comprises first and second substantially semicylindrical shaped portions of fused silica disposed in closely spaced relationship along an axial plane, a substantially spherical depression defined in one end of each semicylindrical portion and a flat defined on each semicylindrical portion at the other end, a piezoelectric transducer attached to the flat of each semicylindrical portion, and a paraffin coated aluminum film of preselected thickness disposed between and in laminar contact with the semicylindrical portions for preventing acoustic and electrical cross talk between the transducers and between the semicylindrical portions.

Abstract: In accordance with the foregoing principles and objects of the invention, the mitigation of fires in machinery enclosures is achieved by strategic placement of thin narrow strips of intumescent material within the ventilated space between the machinery and a housing enclosing the machinery, whereby, in the event of a fire, the resulting flame contacts the intumescent material causing it to swell and to effectively block air flow through the ventilated space.