Showing papers by "Westinghouse Electric published in 2005"

Multi-piece turbine vane assembly

Abstract: Aspects of the invention relate to a modular turbine vane assembly. The vane assembly includes an airfoil portion, an outer shroud and an inner shroud. The airfoil portion can be made of at least two segments. Preferably, the components are connected together so as to permit assembly and disassembly of the vane. Thus, in the event of damage to the vane, repair involves the replacement of only the damaged subcomponents as opposed to the entire vane. The modular design facilitates the use of various materials in the vane, including materials that are dissimilar. Thus, suitable materials can be selected to optimize component life, cooling air usage, aerodynamic performance, and cost. Because the vane is an assemblage of smaller sub-components as opposed to one unitary structure, the individual components of the vane can be more easily manufactured and more intricate features can be included.

Maggot therapy in "lower-extremity hospice" wound care: fewer amputations and more antibiotic-free days.

Abstract: We sought to assess, in a case-control model, the potential efficacy of maggot debridement therapy in 60 nonambulatory patients (mean ± SD age, 72.2 ± 6.8 years) with neuroischemic diabetic foot wounds (University of Texas grade C or D wounds below the malleoli) and peripheral vascular disease. Twenty-seven of these patients (45%) healed during 6 months of review. There was no significant difference in the proportion of patients healing in the maggot debridement therapy versus control group (57% versus 33%). Of patients who healed, time to healing was significantly shorter in the maggot therapy than in the control group (18.5 ± 4.8 versus 22.4 ± 4.4 weeks). Approximately one in five patients (22%) underwent a high-level (above-the-foot) amputation. Patients in the control group were three times as likely to undergo amputation (33% versus 10%). Although there was no significant difference in infection prevalence in patients undergoing maggot therapy versus controls (80% versus 60%), there were significantly more antibiotic-free days during follow-up in patients who received maggot therapy (126.8 ± 30.3 versus 81.9 ± 42.1 days). Maggot debridement therapy reduces short-term morbidity in nonambulatory patients with diabetic foot wounds. (J Am Podiatr Med Assoc 95(3): 254-257, 2005)

High-resolution alpha-particle spectrometry using 4H silicon carbide semiconductor detectors

Abstract: SiC detectors with active volume dimensions sufficient to stop alpha particles have been manufactured and tested. A linear energy response and excellent energy resolution have been obtained for various alpha emitters in the 3.18-MeV to 8.38-MeV energy range. Evaluation of the contributing factors to the SiC detector energy resolution indicates that the measured values for the full width at half maximum (FWHM) are limited by energy straggling of the alpha particles as they pass through the metallic contact layers that comprise the entrance window to the detector. Even with this component included in the measured FWHM, the measured values are comparable to those achievable with silicon alpha spectrometers. The possibility that the energy resolution that can be achieved with SiC may surpass that of silicon can not be excluded. SiC alpha spectrometers are expected to be useful in many nuclear applications where the ability to operate in high-temperature and high-radiation environments is required. Such applications include monitoring of alpha particles, neutrons, and low-energy gamma rays and X-rays in actinide waste-tank environments as well as neutron and gamma-ray monitoring of spent nuclear fuel assemblies.

Vane assembly with metal trailing edge segment

Abstract: Embodiments of the invention relate to a vane assembly formed by a forward airfoil segment and an aft airfoil segment. The aft segment is made of metal and can define the trailing edge of the vane assembly. The forward segment can be made of ceramic, CMC or metal. The forward and aft segments cannot be directly joined to each other because of differences in their rates of thermal expansion and contraction. The forward and aft segments can be positioned substantially proximate to each other so as to form a gap therebetween. In one embodiment, the gap can be substantially sealed by providing a coupling insert or leaf springs in the gap. A separate metal aft segment can take advantage of the beneficial thermal properties of the metal to improve cooling efficiency at the trailing edge without limiting the rest of the vane to being made out of metal.

ZIRLO™ — An Alloy Development Success

Abstract: Significant data and milestones in the development of the ZIRLO alloy for PWR applications are reviewed. From humble beginnings as an R&D program, an approach to improving the corrosion resistance of zirconium-based alloys was developed. The corrosion resistance of dilute alloys is controlled by the microstructure, and both solid solution and precipitate effects impact corrosion performance. Several transition metals are beneficial for corrosion at low concentrations, but the most favorable alloy system is zirconium-niobium, because it offers flexibility in processing options. Strength of the binary alloys can be improved by additions of tin, which, in combination with low levels of iron, provide corrosion resistance in lithium hydroxide solutions. Numerous experimental ingots, thermo-mechanical processing routes, corrosion tests, and materials characterizations were performed along the path to the final alloy composition. The resulting material, ZIRLO, has proven itself as a successful alloy for PWR fuel cladding and structural applications.

Stacked lamellate assembly

Abstract: A stacked ceramic matrix composite lamellate assembly (10) including shear force bearing structures (48) for resisting relative sliding movement between adjacent lamellae. The shear force bearing structures may take the form of a cross-lamellar stitch (50), a shear pin (62), a warp (90) in the lamellae, a tongue (104) and groove (98) structure, or an inter-lamellar sealing member (112), in various embodiments. Each shear force bearing structure secures a subset of the lamellae, with at least one lamella being common between adjacent subsets in order to secure the entire assembly.

Turbine exhaust water recovery system

Abstract: The exhaust gas of a turbine engine can include water vapor. Aspects of the invention relate to various systems for recovering water from the exhaust gas of a gas turbine engine. In one system, a portion of the exhaust gas can be routed to an absorption chiller. In another system, a portion of the exhaust gas can be routed to a direct contact heat exchanger. In a third system, a portion of the exhaust gas can be routed to a fin-fan cooler. In each of these systems, the portion of gas can be cooled below its dew point temperature to release a portion of its humidity as liquid water. Aspects of the invention can be used with the turbine exhaust of simple and combined cycle power plants. A water recovery system according to aspects of the invention can minimize or eliminate a power plant's dependence on local water sources.

Microstructure and growth mechanism of oxide layers formed on Zr alloys studied with micro-beam synchrotron radiation

Abstract: The structures of oxides formed in water and lithiated water on three Zr-based alloys with varied corrosion behavior were studied with micro-beam synchrotron radiation and optical microscopy. Micro-beam synchrotron radiation (0.2 µm spot) has a unique combination of high elemental sensitivity (ppm level) and fine spatial resolution that allowed the determination of various oxide characteristics such as phase content, texture, grain size, and composition as a function of distance from the oxide-metal interface. Micro-beam X-ray fluorescence shows that the oxides formed in lithiated water have increased levels of Fe absorbed from the autoclave environment indicating greater oxide porosity in these oxides. The phase content, texture, and grain size of oxides were studied in detail using synchrotron radiation micro-beam diffraction for samples corroded in water and lithiated water. A remarkable periodicity was observed in the oxide structures using various techniques including X-ray peak intensities for both monoclinic and tetragonal zirconia, texture, and optical microscopy. The periods were similar to the transition period and were less visible in the oxides that behaved worse in lithiated water. These results are discussed in terms of models of oxide growth and of the differences between alloys.

Apparatus and method of detecting wear in an abradable coating system

Abstract: A component for use in a combustion turbine (10) is provided that includes a substrate (212) and an abradable coating system (216) deposited on the substrate (212). A planar proximity sensor (250) may be deposited beneath a surface of the abradable coating system (216) having circuitry (252) configured to detect intrusion of an object (282) into the abradable coating system (216). A least one connector (52) may be provided in electrical communication with the planar proximity sensor (250) for routing a data signal from the planar proximity sensor (250) to a termination location (59). A plurality of trenches (142) may be formed at respective different depths below the surface of the abradable coating system (216) with a planar proximity sensor (250) deposited within each of the plurality of trenches (142). A processing module (34) may be programmed for receiving data from the planar proximity sensor (250) and calculating a clearance between a row of blades (18,19) within a combustion turbine and the planar proximity sensor (250). The processing module (34) may control a clearance between the row of blades (18) and a ring segment (284) based on data received from the planar proximity sensors (250).

Support system for a composite airfoil in a turbine engine

Abstract: A turbine airfoil support system for coupling together a turbine airfoil formed from two or more components, wherein the support system is particularly suited for use with a composite airfoil. In at least one embodiment, the turbine airfoil support system may be configured to attach shrouds to both ends of an airfoil and to maintain a compressive load on those shrouds while the airfoil is positioned in a turbine engine. Application of the compressive load to the airfoil increases the airfoil's ability to withstand tensile forces encountered during turbine engine operation.

Lamellate CMC structure with interlock to metallic support structure

Abstract: A component ( 10 ) for a gas turbine engine formed of a stacked plurality of ceramic matrix composite (CMC) lamellae ( 12 ) supported by a metal support structure ( 20 ). Individual lamellae are supported directly by the support structure via cooperating interlock features ( 30, 32 ) formed on the lamella and on the support structure respectively. Mating load-transferring surfaces ( 34, 36 ) of the interlock features are disposed in a plane ( 44 ) oblique to local axes of thermal growth ( 38, 40 ) in order to accommodate differential thermal expansion there between with delta alpha zero expansion (DAZE). Reinforcing fibers ( 62 ) within the CMC material may be oriented in a direction optimized to resist forces being transferred through the interlock features. Individual lamellae may all have the same structure or different interlock feature shapes and/or locations may be used in different groups of the lamellae. Applications for this invention include an airfoil assembly ( 10 ) and a ring segment assembly ( 82 ).

Hybrid electric propulsion system and method

Abstract: A hybrid propulsion system comprising a first energy storage unit operable to supply power to a traction drive motor. A second energy storage unit is coupled with the first energy storage unit to provide additional power on demand do the traction drive motor. An auxiliary power unit (APU) is used to charge the first battery to maintain a desired voltage across the first energy storage unit.

System for actively controlling compressor clearances

Abstract: Aspects of the invention relate to a system and method for actively controlling compressor clearances in a turbine engine by passing a thermal fluid in heat exchanging relation through a compressor vane carrier. During some operational conditions, such as hot restart or spin cool, it may be desirable to heat the vane carrier to enlarge or at least prevent a decrease in compressor clearances. In such cases, a heated thermal fluid can be provided by reclaiming residual exhaust energy from a heat recovery steam generator. At any condition where improved performance is desired, such as at base load operation, the vane carrier can be cooled to minimize compressor clearances. A cooled thermal fluid can be bleed air from an upstream portion of the compressor, water-cooled high pressure bleed air from a downstream portion of the compressor, or feed water from the bottoming cycle in a combined cycle engine.

Method of joining ceramic parts and articles so formed

Abstract: A joining method for assembling components with complex shapes from CMC elements of simpler shapes. A first CMC element ( 30 ) is fabricated and fired to a selected first cured state. A second CMC element ( 36 ) is fabricated and left in a green state, or is fired to a second partially cured state that is less complete than that of the first cured state. The two CMC elements ( 30, 36 ) are joined in a mating interface that captures an inner joining portion ( 38 ) of the second element ( 36 ) within a surrounding outer joining portion ( 32 ) of the first element ( 30 ). The assembled elements ( 30, 36 ) are then fired together, resulting in differential shrinkage that compresses the outer joining portion ( 32 ) onto the inner joining portion ( 38 ), providing a tightly pre-stressed joint. Optionally, a refractory adhesive ( 42 ) may be used in the joint. Shrinkage of the outer joining portion ( 32 ) avoids shrinkage cracks in the adhesive ( 42 ).

Pin-loaded mounting apparatus for a refractory component in a combustion turbine engine

Abstract: An apparatus for mounting a refractory component such as a turbine shroud ring segment (32) with a ceramic core (42) onto a combustion turbine engine structure (34). The ring segment has a ceramic matrix composite skin (40), and optionally, a thermal insulation layer (46). A pin (60) is inserted through a bore (48) in the core and through an attachment bar (54) with ends received in wells (50) in the core. The attachment bar may be attached to a backing member, or tophat (64), by a biasing device (76) that urges the refractory component snugly against the backing member to eliminate vibration. The backing member and refractory component have mating surfaces that may include angled sides (52S, 70). The backing member is attached to the engine structure. Turbine shroud ring segments can be attached by this apparatus to a surrounding structure to form a shroud ring.

Smart component for use in an operating environment

Abstract: A smart component for use in various operating environments such as a casing of a combustion turbine (10). The component may have a substrate (64), a sensor (50) connected with the substrate (64) for sensing a condition of the component within the casing during operation of the combustion turbine (10) and a connector (52) attached to the substrate (64) and in communication with the sensor (50) for routing a data signal from the sensor to a termination location. The component may include a transmitter (54) in communication with the connector (52) for wirelessly transmitting the data signal outside the casing. A transceiver (56) may be located outside the casing for receiving the data signal and transmitting it to a processing module for developing information with respect to a condition of the component or a coating deposited on the component.

Phased array ultrasonic testing system and methods of examination and modeling employing the same

Abstract: A phased array ultrasonic testing system is for examining turbine disc bores and blade attachments for discontinuities, such as stress corrosion cracking. The system is particularly suited to perform an accurate and efficient inspection of components despite their having a relatively complex geometry, such as axial entry blade attachments and bores of associated discs. The system includes a control system with a computer and a controller for programming, emitting, and steering an ultrasonic beam via at least one two-dimensional phased array probe, thereby precisely inspecting the area of interest while simultaneously accommodating the aforementioned complex geometry of the disc or blade attachment. Computer control of the beam permits the number of inspection locations and the number of different probe wedges to be reduced providing for an efficient, timely inspection. Methods of profiling and examining turbine components of known and unknown geometries, are also disclosed.

Ceramic matrix composite airfoil trailing edge arrangement

Abstract: An airfoil (30) having a continuous layer of ceramic matrix composite (CMC) material (34) extending from a suction side (33) to a pressure side (35) around a trailing edge portion (31). The CMC material includes an inner wrap (36) extending around an inner trailing edge portion (38) and an outer wrap (40) extending around an outer trailing edge portion (42). A filler material (44) is disposed between the inner and outer wraps to substantially eliminate voids in the trailing edge portion. The filler material may be pre-processed to an intermediate stage and used as a mandrel for forming the outer trailing edge portion, and then co-processed with the inner and outer wraps to a final form. The filler material may be pre-processed to include a desired mechanical feature such as a cooling passage (22) or a protrusion (48). The filler material may include an upper layer (77) and a lower layer (78) separated by an intermediate layer (76) that extends to between the inner wrap and the outer wrap along the suction and/or pressure sides.

Thin-film nitinol based drug eluting stent

Abstract: A medical device comprising an implantable structure having a thin film layer made from an alloy of nickel and titanium affixed to at least one surface of the implantable structure and at least one therapeutic agent releasably affixed to the thin film layer configured as a substrate for the controlled release of the at least one agent. In an alternative embodiment, a radiopaque material layer may be affixed to the at least one surface of the implantable structure with the thin film layer thereon. The use of a nickel titanium thin film layer has a number of advantages over other potential materials, including more physical contact surface area and the potential for micro surface features to allow adherence of the therapeutic agent.

A handheld and portable microfluidic device to automatically prepare nucleic acids for analysis

Abstract: A handheld and portalbe extraction device (10) is directed to a microfluidic-based system to be used in the field to extract and purify an analyte, preferably a nucleic acid, from a fluid-based sample. Preferably, the fluid-based sample is water-based. The fluid-based sample can also be a biological fluid sample. The handheld and portable extraction device includes a syringe-like device (14) coupled to a purification chip (48). The purification chip is preferably included within a chip block (40), which is removable from the remaining portion of the handheld and portable extraction device. The analyte collected within the purification chip can be later removed and collected for analysis.

High thermal conductivity materials aligned within resins

Abstract: In one embodiment the present invention provides for a high thermal conductivity resin that comprises a host resin matrix 32 a high thermal conductivity filler 30 . The high thermal conductivity filler forms a continuous organic-inorganic composite with the host resin matrix, and the fillers have an aspect ratio of between 3-100. The fillers are substantially evenly distributed through the host resin matrix, and are aligned in essentially the same direction. In some embodiments the resins are highly structured resin types.

High thermal conductivity materials incorporated into resins

Abstract: In one embodiment the present invention provides for a high thermal conductivity resin that comprises a host resin matrix 32 and a high thermal conductivity filler 30. The high thermal conductivity filler forms a continuous organic-inorganic composite with the host resin matrix, and the high thermal conductivity fillers are from 1-1000 nm in length and have an aspect ratio of between 3-100.

Development of Spatially Dependent Resonance Shielding Method

Abstract: A new spatially dependent resonance self-shielding method (SDDM: Spatially Dependent Dancoff Method) was developed based on the generalization of the conventional Dancoff method to multi-regions in a fuel pellet based on the Stoker/Weiss technique. SDDM correctly accounts for radial power distribution within fuel rods in a fuel assembly. SDDM is fully consistent with the conventional method if the pellet is not sub-divided. It also has the advantage of being less computing time consuming when compared to more rigorous resonance shielding method such as sub-group and special fine energy mesh methods. Moreover, it can be installed easily into the lattice physics code widely used in commercial LWR design. To validate the method, spatial concentration of isotopes and burnup distribution within a rod are evaluated using SDDM and the results are compared to the destructive measurement data. From the comparison, it is concluded that the spatially dependent Dancoff method, SDDM, is appropriate for generating the ...

Remotely controlled lighting system and controller switch for operation on same

Abstract: A system for controlling lighting environment, comprising a lighting fixture, a control switch coupled to the fixture, and a communications link between the control switch and a user interface, wherein a user can control a light intensity of a lighting fixture via commands entered into the user interface.

High thermal conductivity materials with grafted surface functional groups

Abstract: In one embodiment the present invention provides for high thermal conductivity materials (30) that have surface functional groups grafted thereto. These grafted surface functional groups then form a continuous bond with a host resin matrix (32) that the high thermal conductivity materials (30) are added to.

CMC component and method of fabrication

Abstract: An airfoil ( 44 ) formed of a plurality of pre-fired structural CMC panels ( 46, 48, 50, 52 ). Each panel is formed to have an open shape having opposed ends ( 54 ) that are free to move during the drying, curing and/or firing of the CMC material in order to minimize interlaminar stresses caused by anisotropic sintering shrinkage. The panels are at least partially pre-shrunk prior to being joined together to form the desired structure, such as an airfoil ( 42 ) for a gas turbine engine. The panels may be joined together using a backing member ( 30 ), using flanged ends ( 54 ) and a clamp ( 56 ), and/or with a bond material ( 36 ), for example.

Hot to cold steam transformer for turbine systems

Abstract: A steam transformer (200) receives steam through a steam inlet (203), and the steam is mixed in a mixing zone (231) with water entering through a water inlet (205). Steam cooled by contact with the water exits the steam transformer through a cold steam outlet (216). Between the mixing zone (231) and the cold steam outlet (216) is positioned a demister (214) that restricts the passage of water droplets. The steam transformer (200) is used to condition the steam temperature in steam turbine and combined cycle turbine facilities when adjustment of steam temperature is required, such as for cold starts of turbines. The steam transformer (200) may be installed into a bypass circuit or directly inline. A number of differing configurations and designs are disclosed.

Cesium Removal from Hanford Tank Waste Solution Using Resorcinol‐Formaldehyde Resin

Abstract: Experiments with Hanford actual waste sample from Tank 241‐AW‐101 and resorcinol‐formaldehyde resin demonstrated that up to 208 BV of cesium (137Cs) can be removed in a single‐pass through an ion exchange column before a 50% breakthrough occurs. This loading performance for the resorcinol‐formaldehyde resin was better than that previously obtained for the baseline resin (SuperLig® 644) under the same experimental conditions. The elution of the resorcinol‐formaldehyde resin with 0.5 M HNO3 was effective requiring only 16.5 BV to elute 99% of the cesium (i.e. C/Co value <0.01) loaded on the column. The peak concentration for 137Cs occurred between 4 and 6 BV with concentration approximately 100 times that of the feed. The metal ions found in the eluate solution above their detection limits were Al, B, Ca, Cs, Na, and Si. Nitrate was the only anion detected and 238Pu, 239/240Pu, and U were slightly enriched in the eluate solution. Large sample dilutions prevented the detection of other species.