Showing papers by "Westinghouse Electric published in 1996"

Coal gasification and hydrogen production system and method

Abstract: A system and method generates electricity and co-produces a hydrogen flow from coal The electricity is generated by a turbine with a topping combustor and a solid oxide fuel cell ("SOFC") reacting syngas The syngas is produced in a coal gasifier with a portion of the compressed air from the turbine, coal, and steam Prior to the syngas being delivered to the topping combustor and the SOFC, it is cleaned and a portion of the hydrogen in the syngas is removed to form the hydrogen flow Additionally, a vitiated air flow from the SOFC is directed to the topping combustor and another portion of the compressed air from the turbine directed to the SOFC after it is heated with the turbine exhaust An aspect of the invention varies the amount of electricity generated and the volume of hydrogen co-produced based upon the demand of electricity and/or the demand of said hydrogen

Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant

Abstract: A fuel cell generator apparatus and method of its operation involves: passing pressurized oxidant gas, (O) and pressurized fuel gas, (F), into fuel cell modules, (10 and 12), containing fuel cells, where the modules are each enclosed by a module housing (18), surrounded by an axially elongated pressure vessel (64), where there is a purge gas volume, (62), between the module housing and pressure vessel; passing pressurized purge gas, (P), through the purge gas volume, (62), to dilute any unreacted fuel gas from the modules; and passing exhaust gas, (82), and circulated purge gas and any unreacted fuel gas out of the pressure vessel; where the fuel cell generator apparatus is transpatable when the pressure vessel (64) is horizontally disposed, providing a low center of gravity.

Rail navigation system

Abstract: Method and apparatus for a railway navigation system which provides information defining the position of a railway vehicle on a track system. The system uses an on-board computer with a track database representing the locations of the rail lines, including locations of curves and switches. The system uses a turn rate indicator and a speedometer means to obtain a value for the curvature of the track on which the railway vehicle moves. Curvature data so obtained is compared with data in the track database to determine the position of the railway vehicle in relation to curves and switches of the track system.

Electrochemical reduction of nitrates and nitrites in alkaline nuclear waste solutions

Abstract: Sodium nitrate and nitrite are major components of alkaline nuclear waste streams and contribute to environmental release hazards. The electrochemical reduction of these materials to gaseous products has been studied in a synthetic waste mixture. The effects of electrode materials, cell design, and other experimental parameters have been investigated. Lead was found to be the best cathode material in terms of current efficiency for the reduction of nitrate and nitrite in the synthetic mix. The current efficiency for nitrite and nitrate removal is improved in divided cells due to the elimination of anodic oxidation of nitrite. Operation of the divided cells at high current densities (300–600 mA cm−2) and high temperatures (80°C) provides more efficient reduction of nitrite and nitrate. Nearly complete reduction of nitrite and nitrate to nitrogen, ammonia, or nitrous oxide was demonstrated in 1000 h tests in a divided laboratory electrochemical flow cell using a lead cathode, Nafion® 417 cation exchange membrane, and oxygen evolving DSA® or platinum clad niobium anode at a current density of 500 mA cm−2 and a temperature of 70° C. Greater than 99% of the nitrite and nitrate was removed from the synthetic waste mix batch in the 1000 h tests at an overall destruction efficiency of 55%. The process developed shows promise for treating large volumes of waste.

A study of equipment sizes and constraints for a unified power flow controller

Abstract: This paper provides a quantitative measurement of the benefit that a unified power flow controller (UPFC) can provide to increase firm power transfer between two large power systems Included is a complete model for a UPFC control system that contains bus voltage control by the shunt inverter, real power transfer between the shunt and series inverters, and real and reactive power control for the transmission line into which the series inverter is inserted A significant part of the model is representation of dynamic limits that coordinate injected current limits for the shunt inverter, power transfer limits between inverters, voltage injection limits for the series inverter, current limits for the series inverter and line voltage limits for the transmission line This paper contains a simple power system simulation to demonstrate the coordinated dynamic control and illustrate issues that power system planning engineers consider in defining applications for a UPFC

System for operating solid oxide fuel cell generator on diesel fuel

Abstract: A system is provided for operating a solid oxide fuel cell generator on diesel fuel. The system includes a hydrodesulfurizer which reduces the sulfur content of commercial and military grade diesel fuel to an acceptable level. Hydrogen which has been previously separated from the process stream is mixed with diesel fuel at low pressure. The diesel/hydrogen mixture is then pressurized and introduced into the hydrodesulfurizer. The hydrodesulfurizer comprises a metal oxide such as ZnO which reacts with hydrogen sulfide in the presence of a metal catalyst to form a metal sulfide and water. After desulfurization, the diesel fuel is reformed and delivered to a hydrogen separator which removes most of the hydrogen from the reformed fuel prior to introduction into a solid oxide fuel cell generator. The separated hydrogen is then selectively delivered to the diesel/hydrogen mixer or to a hydrogen storage unit. The hydrogen storage unit preferably comprises a metal hydride which stores hydrogen in solid form at low pressure. Hydrogen may be discharged from the metal hydride to the diesel/hydrogen mixture at low pressure upon demand, particularly during start-up and shut-down of the system.

An electrochemical fuel cell generator having an internal and leak tight hydrocarbon fuel reformer

Abstract: An electrochemical fuel cell generator configuration (10) is made having a generator section (16) which contains a plurality of axially elongated fuel cells (26), each cell containing a fuel electrode (28), air electrode (30), and solid oxide electrolyte (32) between the electrodes, in which axially elongated dividers (58) separate portions of the fuel cells from each other, and where at least one divider (60) also reforms a reformable fuel gas mixture prior to electricity generation reactions, the at least one reformer-divider (62) is hollow (64) having a closed end (70) and an open end (68) entrance for a reformable fuel mixture to pass to the closed end of the divider and then reverse flow and pass back along the hollowed walls to be reformed, and then finally to pass as reformed fuel out of the open end of the divider to contact the fuel cells, and further where the reformer-divider is a composite structure having a gas diffusion barrier (76) of metallic foil surrounding the external walls of the reformer-divider except at the entrance to prevent diffusion of the reformable gas mixture through the divider, and further housed in an outer insulating jacket (78) except at the entrance to prevent short-circuiting of the fuel cells by the gas diffusion barrier.

Radio-based electro-pneumatic control communications system

Abstract: A radio-based, Electro-Pneumatic (EP) rail car braking system supports both End-of-Train (EOT) and Distributed Power Control (DPC) communication systems. The EP rail car braking system operates within existing frequency allocations and meets operational reliability needs by adopting a hybrid, two-band communications scheme. The EP rail car braking system uses a broadcast band for transmitting commands to all cars in the train. Selected cars spaced through the train are designated as repeaters, and a predetermined number of cars are assigned to each repeater for form a group of cars that act as a Local Area Network (LAN). The cars in a group communicate with each other using a low power, spread spectrum band. In response to a command broadcast by a lead locomotive, cars in a group act on the command and transmit status information to their repeater car. The repeater car, in turn, sends back status messages to the lead locomotive on the broadcast band based on consolidation of data received from the cars in its group.

Source and tectonic implications of tonalite-trondhjemite magmatism in the Klamath Mountains

Abstract: In the Klamath Mountains, voluminous tonalite-trondhjemite magmatism was characteristic of a short period of time from about 144 to 136 Ma (Early Cretaceous). It occurred about 5 to 10 m.y. after the ∼165 to 159 Ma Josephine ophiolite was thrust beneath older parts of the province during the Nevadan orogeny (thrusting from ∼155 to 148 Ma). The magmatism also corresponds to a period of slow or no subduction. Most of the plutons crop out in the south-central Klamath Mountains in California, but one occurs in Oregon at the northern end of the province. Compositionally extended members of the suite consist of precursor gabbroic to dioritic rocks followed by later, more voluminous tonalitic and trondhjemitic intrusions. Most plutons consist almost entirely of tonalite and trondhjemite. Poorly-defined concentric zoning is common. Tonalitic rocks are typically of the low-Al type but trondhjemites are generally of the high-Al type, even those that occur in the same pluton as low-Al tonalite. The suite is characterized by low abundances of K2O, Rb, Zr, and heavy rare earth elements. Sr contents are generally moderate (∼450 ppm) by comparison with Sr-rich arc lavas interpreted to be slab melts (up to 2000 ppm). Initial 87Sr/86Sr, δ18O, and ɛNd are typical of mantle-derived magmas or of crustally-derived magmas with a metabasic source. Compositional variation within plutons can be modeled by variable degrees of partial melting of a heterogeneous metabasaltic source (transitional mid-ocean ridge to island arc basalt), but not by fractional crystallyzation of a basaltic parent. Melting models require a residual assemblage of clinopyroxene+garnet±plagioclase±amphibole; residual plagioclase suggests a deep crustal origin rather than melting of a subducted slab. Such models are consistent with the metabasic part of the Josephine ophiolite as the source. Because the Josephine ophiolite was at low T during Nevadan thrusting, an external heat source was probably necessary to achieve significant degrees of melting; heat was probably extracted from mantle-derived basaltic melts, which were parental to the mafic precursors of the tonalite-trondhjemite suite. Thus, under appropriate tectonic and thermal conditions, heterogeneous mafic crustal rocks can melt to form both low- and high-Al tonalitic and trondhjemitic magmas; slab melting is not necessary.

Gas turbine blade platform cooling concept

Abstract: A turbine blade with a cooling air flow path specifically directed toward cooling the platform portion of the blade root. Cooling air passages are formed in the blade root platform just below its radially outward facing surface on an overhanging portion of the platform opposite the convex surface of the blade airfoil. Each of these passage extends radially outward from an inlet that receives a flow of cooling air, and then extends through the platform. Cavities are formed in a radially inward facing surface of an over hanging portion of the platform opposite the concave surface of the blade airfoil. An impingement plate directs cooling air as jets into these cavities. A passage is connected to the cavities and directs this cooling air through the overhanging portion of the platform opposite the concave surface.

Thermal expansion of metals reinforced with ceramic particles and microcellular foams

Abstract: The thermal expansion of three isotropic metal-matrix composites, reinforced with SiC particles or microcellular foam, is measured between 25 °C and 325 °C. All three composites show initial co-efficient of thermal expansion (CTE) values in agreement with the Turner model predictions, and near Schapery’s lower elastic bound for CTE. At higher temperatures, the CTE of foam-reinforced Al decreases, while that of the two particle-reinforced composites increases. These observations are interpreted as resulting from the presence of a very small fraction of microscopic voids within the infiltrated composites. This interpretation is confirmed with finite-element simulations of the influence of voids, cracks, and reinforcement convexity in two-dimensional (2-D) composites featuring an interconnected reinforcement of SiC surrounding isolated Al phase regions, thermally cycled from an elevated processing temperature and deforming in generalized plane strain.

Train brake performance monitor

Abstract: Method and apparatus for monitoring brake performance and updating information relating to brake performance while a train is in motion. A computer on the train is provided with inputs for grade information, axle speed, brakepipe pressure, and locomotive tractive effort. During brake applications when the train is in motion, calculations are made by the computer to update parameters which relate to braking performance, and to generate signals representing those parameters.

Selectable grade and uniform net shoe force braking for railway freight vehicle

Abstract: A railway freight brake method and apparatus for operating vehicles in a freight train having a locomotive and a number of railway freight vehicles wherein the individual railway freight vehicles can be controlled in a grade descending mode. When desired, such as when the locomotive transmits a grade mode signal to the individual vehicles, the individual vehicles can brake to produce a generally uniform net shoe force on the wheels of the vehicles. The generally uniform net shoe force can be limited on each vehicle to a value or ratio, such as a percentage of net braking ratio of the given vehicle. On-board calculations can be done in a microprocessor to calculate the vehicle brake cylinder pressure corresponding to the desired net shoe force. This calculation can be done using car parameters stored on-board the vehicle.

Use of Fish Communities to Assess Environmental Impacts in South Carolina Coastal Plain Streams

Abstract: We developed an index of biotic integrity (IBI) and a biotic index based on fish species richness (FSBI) to assess the ecological health of streams on the Savannah River Site, a 780-km2 U.S. Department of Energy facility located in the Sand Hills ecoregion on the upper coastal plain of South Carolina. To maintain the responsiveness of the IBI to a variety of impacts yet incorporate sufficient ecoregion specificity to achieve acceptable accuracy, we included metrics from each of six metric categories proven useful in other ecoregions (species number, species composition, trophic composition, local indicator species, fish abundance, and fish condition) but selected specific metrics within each category based on their ability to discriminate between disturbed and undisturbed sites in the Sand Hills ecoregion. We also developed a procedure based on species–area curves to remove the potentially confounding effects of site-specific differences in sample unit size and sampling effort from species number...

Hydrogen pickup and redistribution in alpha-annealed Zircaloy-4

Abstract: Zircaloy-4, which is widely used as a core structural material in Pressurized-Water Reactors (PWR), picks up hydrogen during service. Hydrogen solubility in Zircaloy-4 is low and hydrides precipitate after the Zircaloy-4 matrix becomes supersaturated with hydrogen. These hydrides embrittle the Zircaloy-4. To study hydrogen pickup and concentration, a postirradiation nondestructive radiographic technique for measuring hydrogen concentration was developed and qualified. Experiments on hydrogen pickup were conducted in the Advanced Test Reactor (ATR). Ex-reactor tests were conducted to determine the conditions for which hydrogen would dissolve, migrate, and precipitate. Finally, a phenomenological model for hydrogen diffusion was indexed to the data. This presentation describes the equipment and the model, presents the results of experiments, and compares the model predictions to experimental results.

Rugged fiber optic probe for raman measurement

Abstract: An optical probe for conducting light scattering analysis is disclosed. The probe comprises a hollow housing and a probe tip. A fiber assembly made up of a transmitting fiber and a receiving bundle is inserted in the tip. A filter assembly is inserted in the housing and connected to the fiber assembly. A signal line from the light source and to the spectrometer also is connected to the filter assembly and communicates with the fiber assembly. By using a spring-loaded assembly to hold the fiber connectors together with the in-line filters, complex and sensitive alignment procedures are avoided. The close proximity of the filter assembly to the probe tip eliminates or minimizes self-scattering generated by the optical fiber. Also, because the probe can contact the sample directly, sensitive optics can be eliminated.

A critical look at the performance advantages and limitations of 4H-SiC power UMOSFET structures

Abstract: A realistic performance projection of 4H-SiC UMOSFET structures based on electric field in the gate insulator consistent with long-term reliability of insulator is provided for the breakdown voltage in the range of 600 to 1500 V. The use of P/sup +/ polysilicon gate leads to higher breakdown voltage as the Fowler Nordheim injection from the gate electrode is reduced. It is concluded that the insulator reliability is the limiting factor and therefore the high temperature operation of these devices may not be practical.

Method of determining car position

Abstract: A system and method for determining the position of each railroad vehicle within a train consist is disclosed. The train consist includes a locomotive, at least one trainline and at least one railroad vehicle. The locomotive has a computer. The at least one trainline has a power line for supplying power to the computer and to each railroad vehicle. The system includes the computer as programmed, a vehicle computing device incorporated into each railroad vehicle, and the at least one trainline interconnecting the computer with each vehicle computing device. Each vehicle computing device contains a unique identification code. Each vehicle computing device can apply to and sense from the power line an electrical signal. The computer via the program commands sequentially each vehicle computing device, via the identification codes, to so apply the electrical signal. Each time the computer so commands one of the vehicle computing devices, all of the other vehicle computing devices located between the locomotive and the vehicle computing device which applied the electrical signal sense the electrical signal. All of the other vehicle computing devices that sensed the electrical signal then respond to the computer, via the at least one trainline, that the electrical signal was sensed. The computer, after having commanded all of the vehicle computing devices and having received the responses therefrom, automatically determines the position of each railroad vehicle relative to all other railroad vehicles within the train consist.

Freight brake control using train net braking ratio

Abstract: A railway freight brake system for operating vehicles in a train wherein each vehicle responds in braking situations as if its effective net braking ratio was a desired train net braking ratio. Embodiments include vehicles receiving a brake signal and utilizing either a received train net braking ratio or utilizing a stored on-board train net braking ratio to control pneumatic equipment on-board the vehicle to produce brake forces on the vehicle generally corresponding to the net braking ratio of the train. Some embodiments use a common train line control to communicate both train net braking ratio and brake signals to the individual vehicle. Individual vehicles can receive periodic or initial train net brake ratio values.

Vehicle control system

Abstract: The present invention relates to a vehicle control system, for example for use in signalling vehicles moving within a transport system such as a railway.

White-light imaging by use of a multiple passband acousto-optic tunable filter.

Abstract: White-light imaging was accomplished by operation of a TeO(2) acousto-optic tunable filter (AOTF) with 40 simultaneous overlapping passbands from 400 to 700 nm. The AOTF was chromatically compensated by a wedge applied to the output surface of the AOTF, and the measured spatial resolution correlated well with predictions. Switching off specific rf's applied to the AOTF produced optical rejection corresponding to the inactive passbands. A rejection ratio of 30 dB was demonstrated, and the rejection level was found to be controlled by leakage through the sidelobes of adjacent passbands.

Method and apparatus for determining the thickness of several layers superimposed on a substrate

Abstract: A method and apparatus for determining the thickness of at least one layer superimposed on a substrate, at least one of the layers or the substrate being a conductor of electricity. The method includes the steps of generating an electromagnetic alternating field in the vicinity of the outer most layer with a coil in order to cause any currents to be generated in the conductor which act upon the alternating field. The frequency of the alternating field is adjusted to at least two different frequencies and is measured at these frequencies. The thickness of the layers is then determined based on the measurements and the electromagnetic properties of the substrate and the layers.

An electrochemical energy conversion and storage system

Abstract: An apparatus for and a method of storing electrical energy as chemical energy and recovering the electrical energy from stored chemical energy by operating an electrochemical cell in two modes, such as a high temperature, solid oxide electrolyte electrochemical cell, in an energy storage mode and an energy recovery mode, is characterized by the steps, in an energy storage mode, of: (A) supplying external electrical energy to electrical leads, and H2O (steam) gas to a cathode of at least one electrochemical cell (56) operating as an electrolysis cell using a solid oxide electrolyte (60) between two electrodes (58 and 62), the electrolysis cell operating to produce H2 gas and O2 gas; (B) passing the H2 gas into an energy storage bed reactor (88) containing iron oxide (90), to produce iron metal (Fe) in the energy storage reactor and H2O (steam); (C) recirculating the H2O (steam) to the electrolysis cell to be electrolyzed; and, (D) repeating steps (A to C) until substantially complete conversion of iron oxide to iron metal, for chemical energy storage of electrical energy; and, further characterized by the steps, in an energy recovery mode, of: (E) supplying H2O (steam) gas to the energy storage bed reactor (88) containing iron metal (Fe) (90) to produce iron oxide (FeO) in the energy storage reactor and H2 gas; (F) passing the H2 gas to an electrode of at least one electrochemical cell operating as a fuel cell and supplying O2 gas or air to the other electrode to produce electrical energy and H2O (steam); (G) recirculating the H2O (steam) produced to the energy storage bed reactor (88); (H) repeating steps (E to G) until substantially complete conversion of iron metal to iron oxide and H2 gas for electrical energy recovery from chemical energy storage; and, (I) recovering the electrical energy produced.

Carrier tracking technique and apparatus having automatic flywheel/tracking/reacquisition control and extended signal to noise ratio

Abstract: The carrier tracking loop technique and apparatus provides smooth, accurate frequency tracking, fast reacquisition and doppler tracking over a wide dynamic range. The loop parameters of the carrier tracking loop are varied as a function of mode, i.e. flywheel, tracking or reacquisition modes. The various modes of operation are automatically detected and loop operation is enhanced by non-linear techniques. The enhancements include fourth power sample normalization to improve performance over a large dynamic range and to ease fixed point scaling. A slope limiter is included which aids in coherent detection by reducing phase noise introduced by the carrier tracking loop. Also, a predifferentiation filter further aids in coherent detection by reducing phase noise.

The Cascaded Humidified Advanced Turbine (CHAT)

Abstract: This paper introduces the Cascaded Humidified Advanced Turbine (CHAT) plant, a gas turbine based power generation plant utilizing intercooling, reheat, and humidifi- cation. It is based upon the integration of an existing heavy duty gas turbine with an additional shaft comprising industrial compressors and high pressure expander. CHAT capitalizes on the latest proven gas turbine technology, which, combined with a sophisticated thermal cycle configuration, results in substantial improvement in gas turbine efficiency, compared to a simple cycle, while still maintaining typical advantages and merits of a combustion turbine plant. Built with a commercial combustion turbine and available industrial compressors and expanders, the CHAT plant does not require extensive product development and testing. As a result, the CHAT power plant can be offered with specific capital costs up to 20 percent lower than the combined cycle plant, and with competing efficiency. Compared to a combined cycle plant, the CHAT plant offers lower emissions (due to air humidification) and other significant operating advantages with regard to start-up time and costs, better efficiency at part load, lower power degradation at higher ambient temperatures, and simpler operations and maintenance due to elimination of the complexities and costs associated with steam production. The CHAT plant also integrates very effectively with coal gasification and particularly well with the water quench design. This feature has been discussed in previous publications.

Principles of the development of a silica dielectric for microelectronics packaging

Abstract: Recognizing that speed, size, reliability, and cost are the principal driving forces for advanced electronic packages, this review article describes the much needed development of a new, phase transformation-free, single-phase silica dielectric with a dielectric constant (k) of about 4, the lowest among the inorganic oxides, and a coefficient of thermal expansion (CTE) of about 3 ppm/°C, similar to that of Si. This dielectric, consisting largely of SiO2, represents a gain in media speed by about 50% over alumina dielectric, combined with an improvement in reliability of the package by a factor of about 1000. The feature size and system cost can also be drastically reduced by using this dielectric. It is made from a mixture of binary borosilicate glasses that normally exhibit an undesirable characteristic of precipitating cristobalite during sintering that severely weakens the structure. The most important aspect of this article is the design and development of a strategy that prevents the cristobalite growth by incorporating a crystal growth inhibitor in the binary mixture of glasses. Since kinetics, not thermodynamics, are shown to be the key to success of this strategy, the roles of rate-controlling parameters are deliberately emphasized. A working model is delineated to identify compositions that yield a cristobalite-free silica dielectric with values of CTE that match those of Si and GaAs. Critical issues of co-firing between metals and this dielectric are addressed within the context of multilayer packaging fabrication. Finally, a list of measured properties is presented that clearly shows new opportunities for this silica dielectric.

Test results of a space-time adaptive processing system for airborne early warning radar

Abstract: Space-time adaptive processing (STAP) has the potential to improve the performance of an airborne early warning (AEW) radar without the costly antenna refinements normally needed to reduce array sidelobes and, correspondingly, clutter. This paper presents a brief STAP overview and describes a radar system testbed which has been flown to gather data suitable for STAP algorithm development. The testbed consists of a 32 column by 8 row L-band array which feeds both conventional sum and delta analog beamformers as well as 22 independent subapertures. This configuration allows for the direct comparison of conventional and STAP beamforming. Measured data is shown which compares state of the art conventional beamforming with STAP processing. Whereas conventional sidelobes of -30 dBi were measured on a ground range, STAP processing of in-the-air clutter data demonstrated cancellation of as much as -45 dBi.

Insert type member for use in a flexible type pump diaphragm

Abstract: An insert member for use in a flexible diaphragm portion of a pump which enables such flexible diaphragm portion of such pump to be provided with a substantially uniform non-obtrusive surface area that will be positioned in such pump for intimate contact with a material to be pumped. Such insert member includes a first disc-like portion having both a first predetermined size and a first predetermined configuration. There is also a second disc-like portion having both a second predetermined size and a second predetermined configuration. The second disc-like portion is secured adjacent one surface thereof to a first surface of the first disc-like portion and such second disc-like portion extends from the first surface of such first disc-like portion for a predetermined distance. This second disc-like portion is disposed substantially in a center portion of the first surface of such first disc-like portion. A plurality of apertures are formed through the first disc-like portion which have a third predetermined size and a third predetermined configuration. This plurality of apertures provides an overall predetermined open area through the first disc-like portion for receiving a rubber compound therein and thereby significantly improve bonding of the improved insert type member to such flexible diaphragm portion of such pump. A securing means is engageable at least with the second disc-like portion for securing the insert member to an elongated piston rod-like member disposed for reciprocal movement within such pump.