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Sample records for advanced electric heat

  1. Development of electrical feedback controlled heat pipes and the advanced thermal control flight experiment

    NASA Technical Reports Server (NTRS)

    Bienert, W. B.

    1974-01-01

    The development and characteristics of electrical feedback controlled heat pipes (FCHP) are discussed. An analytical model was produced to describe the performance of the FCHP under steady state and transient conditions. An advanced thermal control flight experiment was designed to demonstrate the performance of the thermal control component in a space environment. The thermal control equipment was evaluated on the ATS-F satellite to provide performance data for the components and to act as a thermal control system which can be used to provide temperature stability of spacecraft components in future applications.

  2. Electric Adsorption Heat Pump for Electric Vehicles: Electric-Powered Adsorption Heat Pump for Electric Vehicles

    SciTech Connect

    2011-11-21

    HEATS Project: PNNL is developing a new class of advanced nanomaterial called an electrical metal organic framework (EMOF) for EV heating and cooling systems. The EMOF would function similar to a conventional heat pump, which circulates heat or cold to the cabin as needed. However, by directly controlling the EMOF's properties with electricity, the PNNL design is expected to use much less energy than traditional heating and cooling systems. The EMOF-based heat pumps would be light, compact, efficient, and run using virtually no moving parts.

  3. Electric heating pad burns.

    PubMed

    Bill, T J; Edlich, R F; Himel, H N

    1994-01-01

    Patients with sensory deficits are especially prone to heating pad burns. Two cases are reported of patients with anesthetic skin who received partial and full-thickness burns of their feet from an electric heating pad. These burn injuries could have been prevented if the patients understood the potential hazard of heating pads.

  4. Sodium heat engine electrical feedthrough

    DOEpatents

    Weber, N.

    1985-03-19

    A thermoelectric generator device which converts heat energy to electrical energy is disclosed. An alkali metal is used with a solid electrolyte and a hermetically sealed feedthrough structure. 4 figs.

  5. Advanced heat pump cycle

    SciTech Connect

    Groll, E.A.; Radermacher, R.

    1993-07-01

    The desorption and absorption process of a vapor compression heat pump with a solution circuit (VCHSC) proceeds at gliding temperature intervals, which can be adjusted over a wide range. In case that the gliding temperature intervals in the desorber and the absorber overlap, a modification of the VCHSC employing a desorber/absorber heat exchange (DAHX) can be introduced, which results in an extreme reduction of the pressure ratio. Although the DAHX-cycle has features of a two-stage cycle, it still requires only one solution pump, one separator and one compressor. Such a cycle for the working pair ammonia/water is built in the Energy Laboratory of the Center for Environmental Energy Engineering at the University of Maryland. The experimental results obtained with the research plant are discussed and compared to those calculated with a simulation program. The possible temperature lift between heat source and heat sink depending on the achievable COP are presented.

  6. Solar thermoelectricity via advanced latent heat storage

    NASA Astrophysics Data System (ADS)

    Olsen, M. L.; Rea, J.; Glatzmaier, G. C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, A. D.; Bobela, D.; Bonner, R.; Weigand, R.; Campo, D.; Parilla, P. A.; Siegel, N. P.; Toberer, E. S.; Ginley, D. S.

    2016-05-01

    We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a "thermal valve," which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

  7. Solar Thermoelectricity via Advanced Latent Heat Storage

    SciTech Connect

    Olsen, Michele L.; Rea, J.; Glatzmaier, Greg C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, Azure D.; Bobela, David; Bonner, R.; Weigand, R.; Campo, D.; Parilla, Philip A.; Siegel, N. P.; Toberer, Eric S.; Ginley, David S.

    2016-05-31

    We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a 'thermal valve,' which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

  8. Advanced heat pump research and development

    NASA Astrophysics Data System (ADS)

    Kuliasha, M. A.

    The Office of Building Energy Research and Development of the U.S. Department of Energy (DOE), has been funding R&D in advanced heat pumps and appliances since 1976. Much of that research has been managed for DOE by the Oak Ridge National Laboratory (ORNL). The objective of the Building Equipment Research (BER) program at ORNL has been to generate new concepts and develop a technology base for improving the energy efficiency and load characteristics of energy conversion equipment used in residential and commercial buildings. The research being pursued to achieve these objectives falls under three general areas: thermally activated heat pumps (TAHP), refrigeration systems, and building equipment systems. The TAHP work is concentrated on three technologies: (1) absorption heat pumps; (2) Stirling engine-driven heat pumps; and (3) internal combustion (IC) engine-driven heat pumps. Major project areas in refrigeration systems research include electric heat pumps, ground-coupled heat pumps, and refigerant mixtures. In the building equipment systems areas, project areas include advanced distribution systems, advanced insulation for appliances, and commercial building equipment.

  9. Advances in Electrically Driven Thermal Management

    NASA Technical Reports Server (NTRS)

    Didion, Jeffrey R.

    2017-01-01

    Electrically Driven Thermal Management is a vibrant technology development initiative incorporating ISS based technology demonstrations, development of innovative fluid management techniques and fundamental research efforts. The program emphasizes high temperature high heat flux thermal management required for future generations of RF electronics and power electronic devices. This presentation reviews i.) preliminary results from the Electrohydrodynamic (EHD) Long Term Flight Demonstration launched on STP-H5 payload in February 2017 ii.) advances in liquid phase flow distribution control iii.) development of the Electrically Driven Liquid Film Boiling Experiment under the NASA Microgravity Fluid Physics Program.

  10. Plasma Heating: An Advanced Technology

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Mercury and Apollo spacecraft shields were designed to protect astronauts from high friction temperatures (well over 2,000 degrees Fahrenheit) when re-entering the Earth's atmosphere. It was necessary to test and verify the heat shield materials on Earth before space flight. After exhaustive research and testing, NASA decided to use plasma heating as a heat source. This technique involves passing a strong electric current through a rarefied gas to create a plasma (ionized gas) that produces an intensely hot flame. Although NASA did not invent the concept, its work expanded the market for commercial plasma heating systems. One company, Plasma Technology Corporation (PTC), was founded by a member of the team that developed the Re-entry Heating Simulator at Ames Research Center (ARC). Dr. Camacho, President of PTC, believes the technology has significant environmental applications. These include toxic waste disposal, hydrocarbon, decomposition, medical waste disposal, asbestos waste destruction, and chemical and radioactive waste disposal.

  11. Thermally effective, electrically isolating heat intercept connections

    SciTech Connect

    Niemann, R.C.; Gonczy, J.D.; Nicol, T.H.

    1995-06-01

    Electrical and electronic equipment often require thermally effective beat intercept connections that provide electrical isolation. Such connections can be developed by clamping, with a thermal-interference fit, an electrically insulating cylindrical tube between a central disk and an outer ring. Heat flows radially through the disk-tube-ring assembly. Thermal effectiveness, i.e., {Delta}T for a given heat flux, and electrical isolation are controlled by tube geometry and material and by connection-assembly details. Connections of this type are being developed as cryogenic heat intercepts for electrical current leads that employ high-temperature superconductors. We discuss the design considerations and details of a beat intercept connection that transfers a 45-w thermal load at 60 K with a {Delta}T of {approx} 10 K while providing 7.5 kV electrical isolation. Prototype heat intercept connections have been evaluated for their thermal and electrical performance, and the results are presented.

  12. Zone heated diesel particulate filter electrical connection

    DOEpatents

    Gonze, Eugene V.; Paratore, Jr., Michael J.

    2010-03-30

    An electrical connection system for a particulate filter is provided. The system includes: a particulate filter (PF) disposed within an outer shell wherein the PF is segmented into a plurality of heating zones; an outer mat disposed between the particulate filter and the outer shell; an electrical connector coupled to the outer shell of the PF; and a plurality of printed circuit connections that extend along the outer surface of the PF from the electrical connector to the plurality of heating zones.

  13. Electrical assembly having heat sink protrusions

    DOEpatents

    Rinehart, Lawrence E.; Romero, Guillermo L.

    2009-04-21

    An electrical assembly, comprising a heat producing semiconductor device supported on a first major surface of a direct bond metal substrate that has a set of heat sink protrusions supported by its second major surface. In one preferred embodiment the heat sink protrusions are made of the same metal as is used in the direct bond copper.

  14. Electrically heated DPF start-up strategy

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2012-04-10

    An exhaust system that processes exhaust generated by an engine has a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates in the exhaust. An electrical heater is disposed upstream of the DPF and selectively heats the exhaust to initiate combustion of the particulates. Heat generated by combustion of particulates in the heater induces combustion of particulates within the DPF. A control module selectively enables current flow to the electrical heater for an initial period of a DPF regeneration cycle, and limits exhaust flow while the electrical heater is heating to a predetermined soot combustion temperature.

  15. Advanced heat receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, James; Saunders, Roger; Batchelder, Gary

    1988-01-01

    Solar Dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  16. NEP heat pipe radiators. [Nuclear Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Ernst, D. M.

    1979-01-01

    This paper covers improvements of heat pipe radiators for the thermionic NEP design. Liquid metal heat pipes are suitable as spacecraft radiator elements because of high thermal conductance, low mass and reliability, but the NEP thermionic system design was too large and difficult to fabricate. The current integral collector-radiator design consisting of several layers of thermionic converters, the annular-tangential collector heat pipe, the radiator heat pipe, and the transition zone designed to minimize the temperature difference between the collector heat pipe and radiator heat pipe are described. Finally, the design of micrometeoroid armor protection and the fabrication of the stainless steel annular heat pipe with a tangential arm are discussed, and it is concluded that the heat rejection system for the thermionic NEP system is well advanced, but the collector-radiator heat pipe transition and the 8 to 10 m radiator heat pipe with two bends require evaluation.

  17. Advanced Print Reading. Heating, Ventilation and Air Conditioning.

    ERIC Educational Resources Information Center

    Oregon State Dept. of Education, Salem.

    This is a workbook for students learning advanced blueprint reading for heating, ventilation, and air conditioning applications. The workbook contains eight units covering the following material: architectural working drawings; architectural symbols and dimensions; basic architectural electrical symbols; wiring symbols; basic piping symbols;…

  18. Electric heating for high-temperature heat transport fluids

    NASA Astrophysics Data System (ADS)

    Holmes, J. T.

    1985-12-01

    Recent experiences with electric resistance heaters at the solar Central Receiver Test Facility are described. These heaters are used to preheat or maintain equipment used with molten nitrate salt or liquid sodium heat transfer fluids. Results of extensive testing performed to improve the reliability of similar heating systems used in the development program for the sodium-cooled liquid metal fast breeder nuclear reactor are also reviewed. Recommendations are made for increasing the reliability of trace heating systems for high-melting-point heat transfer fluids including thermal design, heating element selection, installation, insulation, and controls.

  19. Indoor unit for electric heat pump

    DOEpatents

    Draper, R.; Lackey, R.S.; Fagan, T.J. Jr.; Veyo, S.E.; Humphrey, J.R.

    1984-05-22

    An indoor unit for an electric heat pump is provided in modular form including a refrigeration module, an air mover module, and a resistance heat package module, the refrigeration module including all of the indoor refrigerant circuit components including the compressor in a space adjacent the heat exchanger, the modules being adapted to be connected to air flow communication in several different ways as shown to accommodate placement of the unit in various orientations. 9 figs.

  20. Harvesting Electricity From Wasted Heat

    ScienceCinema

    Schwede, Jared

    2016-07-12

    Scientists as SLAC National Laboratory explain the concept, Photon Enhanced Thermionic Emission (PETE), and how this process can capture more energy from photovoltaic panels by harnessing heat energy from sunlight.

  1. Harvesting Electricity From Wasted Heat

    SciTech Connect

    Schwede, Jared

    2014-06-30

    Scientists as SLAC National Laboratory explain the concept, Photon Enhanced Thermionic Emission (PETE), and how this process can capture more energy from photovoltaic panels by harnessing heat energy from sunlight.

  2. Advances in Solar Heating and Cooling Systems

    ERIC Educational Resources Information Center

    Ward, Dan S.

    1976-01-01

    Reports on technological advancements in the fields of solar collectors, thermal storage systems, and solar heating and cooling systems. Diagrams aid in the understanding of the thermodynamics of the systems. (CP)

  3. Deep Eutectic Salt Formulations Suitable as Advanced Heat Transfer Fluids

    SciTech Connect

    Raade, Justin; Roark, Thomas; Vaughn, John; Bradshaw, Robert

    2013-07-22

    Concentrating solar power (CSP) facilities are comprised of many miles of fluid-filled pipes arranged in large grids with reflective mirrors used to capture radiation from the sun. Solar radiation heats the fluid which is used to produce steam necessary to power large electricity generation turbines. Currently, organic, oil-based fluid in the pipes has a maximum temperature threshold of 400 °C, allowing for the production of electricity at approximately 15 cents per kilowatt hour. The DOE hopes to foster the development of an advanced heat transfer fluid that can operate within higher temperature ranges. The new heat transfer fluid, when used with other advanced technologies, could significantly decrease solar electricity cost. Lower costs would make solar thermal electricity competitive with gas and coal and would offer a clean, renewable source of energy. Molten salts exhibit many desirable heat transfer qualities within the range of the project objectives. Halotechnics developed advanced heat transfer fluids (HTFs) for application in solar thermal power generation. This project focused on complex mixtures of inorganic salts that exhibited a high thermal stability, a low melting point, and other favorable characteristics. A high-throughput combinatorial research and development program was conducted in order to achieve the project objective. Over 19,000 candidate formulations were screened. The workflow developed to screen various chemical systems to discover salt formulations led to mixtures suitable for use as HTFs in both parabolic trough and heliostat CSP plants. Furthermore, salt mixtures which will not interfere with fertilizer based nitrates were discovered. In addition for use in CSP, the discovered salt mixtures can be applied to electricity storage, heat treatment of alloys and other industrial processes.

  4. Drafting. Advanced Print Reading--Electrical.

    ERIC Educational Resources Information Center

    Oregon State Dept. of Education, Salem.

    This document is a workbook for drafting students learning advanced print reading for electricity applications. The workbook contains seven units covering the following material: architectural working drawings; architectural symbols and dimensions; basic architectural electrical symbols; wiring symbols; riser diagrams; schematic diagrams; and…

  5. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristic parameters of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, argon MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. Overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  6. Advanced Gradient Heating Facility (AGHF)

    NASA Technical Reports Server (NTRS)

    1998-01-01

    This section of the publication includes papers entitled: (1) Coupled growth in hypermonotectics; (2) Directional solidification of refined Al-4 wt.% Cu alloys; (3) Effects of convection on interface curvature during growth of concentrated ternary compounds; (4) Directional solidification of Al-1.5 wt.% Ni alloys; (5) Interactive response of advancing phase boundaries to particles; (6) INTeractive Response of Advancing Phase boundaries to Particles-INTRAPP; and (7) Particle engulfment and pushing by solidifying interfaces.

  7. Recent advances in coronal heating

    PubMed Central

    De Moortel, Ineke; Browning, Philippa

    2015-01-01

    The solar corona, the tenuous outer atmosphere of the Sun, is orders of magnitude hotter than the solar surface. This ‘coronal heating problem’ requires the identification of a heat source to balance losses due to thermal conduction, radiation and (in some locations) convection. The review papers in this Theo Murphy meeting issue present an overview of recent observational findings, large- and small-scale numerical modelling of physical processes occurring in the solar atmosphere and other aspects which may affect our understanding of the proposed heating mechanisms. At the same time, they also set out the directions and challenges which must be tackled by future research. In this brief introduction, we summarize some of the issues and themes which reoccur throughout this issue. PMID:25897095

  8. Recent advances in coronal heating.

    PubMed

    De Moortel, Ineke; Browning, Philippa

    2015-05-28

    The solar corona, the tenuous outer atmosphere of the Sun, is orders of magnitude hotter than the solar surface. This 'coronal heating problem' requires the identification of a heat source to balance losses due to thermal conduction, radiation and (in some locations) convection. The review papers in this Theo Murphy meeting issue present an overview of recent observational findings, large- and small-scale numerical modelling of physical processes occurring in the solar atmosphere and other aspects which may affect our understanding of the proposed heating mechanisms. At the same time, they also set out the directions and challenges which must be tackled by future research. In this brief introduction, we summarize some of the issues and themes which reoccur throughout this issue.

  9. Advanced electrical power system technology for the all electric aircraft

    NASA Technical Reports Server (NTRS)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg. Previously announced in STAR as N83-24764

  10. Advanced electrical power system technology for the all electric aircraft

    NASA Technical Reports Server (NTRS)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg.

  11. Indoor unit for electric heat pump

    DOEpatents

    Draper, Robert; Lackey, Robert S.; Fagan, Jr., Thomas J.; Veyo, Stephen E.; Humphrey, Joseph R.

    1984-01-01

    An indoor unit for an electric heat pump is provided in modular form including a refrigeration module 10, an air mover module 12, and a resistance heat package module 14, the refrigeration module including all of the indoor refrigerant circuit components including the compressor 36 in a space adjacent the heat exchanger 28, the modules being adapted to be connected to air flow communication in several different ways as shown in FIGS. 4-7 to accommodate placement of the unit in various orientations.

  12. Advanced batteries for electric vehicles

    NASA Astrophysics Data System (ADS)

    Nelson, Paul A.

    1989-03-01

    Over the past twenty years, some of the most difficult problems have been solved in the development of long-lived lithium/sulfide secondary batteries having molten chloride electrolytes. Recent tests of Li-Al/FeS2 cells have demonstrated 1000 cycles of operation and the practicality of achieving a specific energy of 175 Wh/kg for prismatic cells. Bipolar cells now under study may achieve even higher specific energy. Also, bipolar cells make possible the use of low-cost coated current collectors for the positive electrode instead of the expensive molybdenum current collectors that have been required for prismatic cells. Very compact batteries to power an electric van have been conceptually designed with this approach. These batteries would provide a range for the loaded vehicle of more than 100 miles for a battery weighing 280 kg, only 15 percent of the loaded vehicle weight (1930 kg).

  13. Advanced Electrical Materials and Component Development

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.

    2003-01-01

    The primary means to develop advanced electrical components is to develop new and improved materials for magnetic components (transformers, inductors, etc.), capacitors, and semiconductor switches and diodes. This paper will give a description and status of the internal and external research sponsored by NASA Glenn Research Center on soft magnetic materials, dielectric materials and capacitors, and high quality silicon carbide (SiC) atomically smooth substrates. The rationale for and the benefits of developing advanced electrical materials and components for the PMAD subsystem and also for the total power system will be briefly discussed.

  14. Advanced Electrical Materials and Components Being Developed

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.

    2004-01-01

    All aerospace systems require power management and distribution (PMAD) between the energy and power source and the loads. The PMAD subsystem can be broadly described as the conditioning and control of unregulated power from the energy source and its transmission to a power bus for distribution to the intended loads. All power and control circuits for PMAD require electrical components for switching, energy storage, voltage-to-current transformation, filtering, regulation, protection, and isolation. Advanced electrical materials and component development technology is a key technology to increasing the power density, efficiency, reliability, and operating temperature of the PMAD. The primary means to develop advanced electrical components is to develop new and/or significantly improved electronic materials for capacitors, magnetic components, and semiconductor switches and diodes. The next important step is to develop the processing techniques to fabricate electrical and electronic components that exceed the specifications of presently available state-of-the-art components. The NASA Glenn Research Center's advanced electrical materials and component development technology task is focused on the following three areas: 1) New and/or improved dielectric materials for the development of power capacitors with increased capacitance volumetric efficiency, energy density, and operating temperature; 2) New and/or improved high-frequency, high-temperature soft magnetic materials for the development of transformers and inductors with increased power density, energy density, electrical efficiency, and operating temperature; 3) Packaged high-temperature, high-power density, high-voltage, and low-loss SiC diodes and switches.

  15. "Nanotechnology Enabled Advanced Industrial Heat Transfer Fluids"

    SciTech Connect

    Dr. Ganesh Skandan; Dr. Amit Singhal; Mr. Kenneth Eberts; Mr. Damian Sobrevilla; Prof. Jerry Shan; Stephen Tse; Toby Rossmann

    2008-06-12

    ABSTRACT Nanotechnology Enabled Advanced industrial Heat Transfer Fluids” Improving the efficiency of Industrial Heat Exchangers offers a great opportunity to improve overall process efficiencies in diverse industries such as pharmaceutical, materials manufacturing and food processing. The higher efficiencies can come in part from improved heat transfer during both cooling and heating of the material being processed. Additionally, there is great interest in enhancing the performance and reducing the weight of heat exchangers used in automotives in order to increase fuel efficiency. The goal of the Phase I program was to develop nanoparticle containing heat transfer fluids (e.g., antifreeze, water, silicone and hydrocarbon-based oils) that are used in transportation and in the chemical industry for heating, cooling and recovering waste heat. Much work has been done to date at investigating the potential use of nanoparticle-enhanced thermal fluids to improve heat transfer in heat exchangers. In most cases the effect in a commercial heat transfer fluid has been marginal at best. In the Phase I work, we demonstrated that the thermal conductivity, and hence heat transfer, of a fluid containing nanoparticles can be dramatically increased when subjected to an external influence. The increase in thermal conductivity was significantly larger than what is predicted by commonly used thermal models for two-phase materials. Additionally, the surface of the nanoparticles was engineered so as to have a minimal influence on the viscosity of the fluid. As a result, a nanoparticle-laden fluid was successfully developed that can lead to enhanced heat transfer in both industrial and automotive heat exchangers

  16. 5. PHOTOGRAPHIC COPY OF ORIGINAL DRAWINGS, ELECTRIC AIR AND HEATING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. PHOTOGRAPHIC COPY OF ORIGINAL DRAWINGS, ELECTRIC AIR AND HEATING UNIT, PLAN AND ELEVATION - Wyoming Air National Guard Base, Electric, Air & Heating Plant, Cheyenne Airport, Cheyenne, Laramie County, WY

  17. Reversible Heating in Electric Double Layer Capacitors

    NASA Astrophysics Data System (ADS)

    Janssen, Mathijs; van Roij, René

    2017-03-01

    A detailed comparison is made between different viewpoints on reversible heating in electric double layer capacitors. We show in the limit of slow charging that a combined Poisson-Nernst-Planck and heat equation, first studied by d'Entremont and Pilon [J. Power Sources 246, 887 (2014), 10.1016/j.jpowsour.2013.08.024], recovers the temperature changes as predicted by the thermodynamic identity of Janssen et al. [Phys. Rev. Lett. 113, 268501 (2014), 10.1103/PhysRevLett.113.268501], and disagrees with the approximative model of Schiffer et al. [J. Power Sources 160, 765 (2006), 10.1016/j.jpowsour.2005.12.070] that predominates the literature. The thermal response to the adiabatic charging of supercapacitors contains information on electric double layer formation that has remained largely unexplored.

  18. Reversible Heating in Electric Double Layer Capacitors.

    PubMed

    Janssen, Mathijs; van Roij, René

    2017-03-03

    A detailed comparison is made between different viewpoints on reversible heating in electric double layer capacitors. We show in the limit of slow charging that a combined Poisson-Nernst-Planck and heat equation, first studied by d'Entremont and Pilon [J. Power Sources 246, 887 (2014)JPSODZ0378-775310.1016/j.jpowsour.2013.08.024], recovers the temperature changes as predicted by the thermodynamic identity of Janssen et al. [Phys. Rev. Lett. 113, 268501 (2014)PRLTAO0031-900710.1103/PhysRevLett.113.268501], and disagrees with the approximative model of Schiffer et al. [J. Power Sources 160, 765 (2006)JPSODZ0378-775310.1016/j.jpowsour.2005.12.070] that predominates the literature. The thermal response to the adiabatic charging of supercapacitors contains information on electric double layer formation that has remained largely unexplored.

  19. Ceramic Technology for Advanced Heat Engines Project

    SciTech Connect

    Not Available

    1990-08-01

    The Ceramic Technology For Advanced Heat Engines Project was developed by the Department of Energy's Office of Transportation Systems (OTS) in Conservation and Renewable Energy. This project, part of the OTS's Advanced Materials Development Program, was developed to meet the ceramic technology requirements of the OTS's automotive technology programs. Significant accomplishments in fabricating ceramic components for the Department of Energy (DOE), National Aeronautics and Space Administration (NASA), and Department of Defense (DOD) advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and data base and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a five year project plan was developed with extensive input from private industry. The objective of the project is to develop the industrial technology base required for reliable ceramics for application in advanced automotive heat engines. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on structural ceramics for advanced gas turbine and diesel engines, ceramic hearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines.

  20. APPARATUS FOR CONVERTING HEAT INTO ELECTRICITY

    DOEpatents

    Crouthamel, C.E.; Foster, M.S.

    1964-01-28

    This patent shows an apparatus for converting heat to electricity. It includes a galvanic cell having an anodic metal anode, a fused salt electrolyte, and a hydrogen cathode having a diffusible metal barrier of silver-- palladium alloy covered with sputtered iron on the side next to the fused electrolyte. Also shown is a regenerator for regenerating metal hydride produced by the galvanic cell into hydrogen gas and anodic metal, both of which are recycled. (AEC)

  1. 46 CFR 169.685 - Electric heating and cooking equipment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Electric heating and cooking equipment. 169.685 Section... More on Vessels of Less Than 100 Gross Tons § 169.685 Electric heating and cooking equipment. (a) Each electric space heater for heating rooms and compartments must be provided with thermal cutouts to...

  2. 46 CFR 169.685 - Electric heating and cooking equipment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Electric heating and cooking equipment. 169.685 Section... More on Vessels of Less Than 100 Gross Tons § 169.685 Electric heating and cooking equipment. (a) Each electric space heater for heating rooms and compartments must be provided with thermal cutouts to...

  3. 46 CFR 169.685 - Electric heating and cooking equipment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Electric heating and cooking equipment. 169.685 Section... More on Vessels of Less Than 100 Gross Tons § 169.685 Electric heating and cooking equipment. (a) Each electric space heater for heating rooms and compartments must be provided with thermal cutouts to...

  4. 46 CFR 169.685 - Electric heating and cooking equipment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Electric heating and cooking equipment. 169.685 Section... More on Vessels of Less Than 100 Gross Tons § 169.685 Electric heating and cooking equipment. (a) Each electric space heater for heating rooms and compartments must be provided with thermal cutouts to...

  5. Development of advanced heat pump. Part 2: Preliminary test of two-stage compression heat pump

    NASA Astrophysics Data System (ADS)

    Iwatsubo, Tetsushiro; Saikawa, Michinori; Hamamatsu, Teruhide

    1988-03-01

    A heat pump driven by electricity is one of the excellent electricity utilization systems and is promoted to be widely used. An advanced heat pump has been investigated to enlarge its applications in the field of hot water supply for domestic use which will be competitive with city gas and air conditioning in large scale buildings. An experimental unit with two-stage compression system was designed, which has the multi-function of air conditioning and hot water supply, and the trial system was fabricated. In the design, followings were considered; cooperative operations of two compressors by inverter driving, the temperature conditions of both the air for the air conditioning and the heat source, additional setting of the intermediate heat exchanger. The test operation was carried out with checking the start up procedure, the control sequence and so on. The probability of five operation modes: cooling, heating, hot water supply, cooling/hot water supply, and heating/hot water supply, were confirmed. In the mode of heating/hot water supply the hot water temperature was increased to 65 C, the excellent performance in hot water supply was demonstrated.

  6. Electrically heated particulate filter using catalyst striping

    DOEpatents

    Gonze, Eugene V; Paratore, Jr., Michael J; Ament, Frank

    2013-07-16

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating is applied to the PF that increases a temperature of the combustion of the particulates within the PF.

  7. Electrically heated particulate filter enhanced ignition strategy

    SciTech Connect

    Gonze, Eugene V; Paratore, Jr., Michael J

    2012-10-23

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material is applied to an exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF. A catalyst coating applied to at least one of the PF and the grid. A control module estimates a temperature of the grid and controls the engine to produce a desired exhaust product to increase the temperature of the grid.

  8. Electrically heated particulate filter embedded heater design

    DOEpatents

    Gonze, Eugene V.; Chapman, Mark R.

    2014-07-01

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine and wherein an upstream surface of the particulate filter includes machined grooves. A grid of electrically resistive material is inserted into the machined grooves of the exterior upstream surface of the PF and selectively heats exhaust passing through the grid to initiate combustion of particulates within the PF.

  9. Ceramic technology for advanced heat engines

    SciTech Connect

    Johnson, D.R.; Schulz, R.B.

    1994-10-01

    The Ceramic Technology Project was initiated in 1983 for the purpose of developing highly reliable structural ceramics for applications in advanced heat engines, such as automotive gas turbines and advanced heavy duty diesel engines. The reliability problem was determined to be a result of uncontrolled populations of processing flaws in the brittle, flaw-sensitive materials, along with microstructural features, such as grain boundary phases, that contribute to time dependent strength reduction in service at high temperatures. The approaches taken to develop high reliability ceramics included the development of tougher materials with greater tolerance to microstructural flaws, the development of advanced processing technology to minimize the size and number of flaws, and the development of mechanical testing methodology and the characterization of time dependent mechanical behavior, leading to a life prediction methodology for structural ceramics. The reliability goals of the program were largely met by 1993, but commercial implementation of ceramic engine components has been delayed by the high cost of the components. A new effort in Cost Effective Ceramics for Heat Engines was initiated in 1993 and is expected to develop the manufacturing technology leading to an order of magnitude cost reduction. The program has been planned for a five year period.

  10. Advances in refrigeration and heat transfer engineering

    DOE PAGES

    Bansal, Pradeep; Cremaschi, Prof. Lorenzo

    2015-05-13

    This special edition of Science and Technology for the Built Environment (STBE) presents selected high quality papers that were presented at the 15th International Refrigeration and Air Conditioning Conference held at Purdue University during July 14-17 2014. All papers went through the additional review before being finally accepted for publication in this special issue of Science and Technology and the Built Environment. Altogether 20 papers made to this special issue that cover a wide range of topics, including advancements in alternative refrigerants, heat exchangers/heat transfer, nano-fluids, systems design and optimization and modeling approaches. Although CO2 may perhaps have been themore » most researched and popular refrigerant in the past decade, R32 is being seriously considered lately as an alternative and environmentally friendly refrigerant for small systems due to its low Global Warming Potential (GWP).« less

  11. Advances in refrigeration and heat transfer engineering

    SciTech Connect

    Bansal, Pradeep; Cremaschi, Prof. Lorenzo

    2015-05-13

    This special edition of Science and Technology for the Built Environment (STBE) presents selected high quality papers that were presented at the 15th International Refrigeration and Air Conditioning Conference held at Purdue University during July 14-17 2014. All papers went through the additional review before being finally accepted for publication in this special issue of Science and Technology and the Built Environment. Altogether 20 papers made to this special issue that cover a wide range of topics, including advancements in alternative refrigerants, heat exchangers/heat transfer, nano-fluids, systems design and optimization and modeling approaches. Although CO2 may perhaps have been the most researched and popular refrigerant in the past decade, R32 is being seriously considered lately as an alternative and environmentally friendly refrigerant for small systems due to its low Global Warming Potential (GWP).

  12. Ash reduction system using electrically heated particulate matter filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J; He, Yongsheng [Sterling Heights, MI

    2011-08-16

    A control system for reducing ash comprises a temperature estimator module that estimates a temperature of an electrically heated particulate matter (PM) filter. A temperature and position estimator module estimates a position and temperature of an oxidation wave within the electrically heated PM filter. An ash reduction control module adjusts at least one of exhaust flow, fuel and oxygen levels in the electrically heated PM filter to adjust a position of the oxidation wave within the electrically heated PM filter based on the oxidation wave temperature and position.

  13. Improved silicon carbide for advanced heat engines

    NASA Technical Reports Server (NTRS)

    Whalen, Thomas J.

    1987-01-01

    This is the second annual technical report entitled, Improved Silicon Carbide for Advanced Heat Engines, and includes work performed during the period February 16, 1986 to February 15, 1987. The program is conducted for NASA under contract NAS3-24384. The objective is the development of high strength, high reliability silicon carbide parts with complex shapes suitable for use in advanced heat engines. The fabrication methods used are to be adaptable for mass production of such parts on an economically sound basis. Injection molding is the forming method selected. This objective is to be accomplished in a two-phase program: (1) to achieve a 20 percent improvement in strength and a 100 percent increase in Weibull modulus of the baseline material; and (2) to produce a complex shaped part, a gas turbine rotor, for example, with the improved mechanical properties attained in the first phase. Eight tasks are included in the first phase covering the characterization of the properties of a baseline material, the improvement of those properties and the fabrication of complex shaped parts. Activities during the first contract year concentrated on two of these areas: fabrication and characterization of the baseline material (Task 1) and improvement of material and processes (Task 7). Activities during the second contract year included an MOR bar matrix study to improve mechanical properties (Task 2), materials and process improvements (Task 7), and a Ford-funded task to mold a turbocharger rotor with an improved material (Task 8).

  14. Advanced wood heating technologies. Final report

    SciTech Connect

    Shelton, J.W.

    1984-08-01

    The residents of the State of New York make heavy use of wood fuel for residential heating. Many advanced technology wood heaters have been introduced recently, accompanied by impressive performance claims relating to increased energy efficiency, decreased creosote accumulation, and decreased emissions. These are important claims, since they translate into fuel conservation, increased safety through fewer chimney fires, and cleaner air. The focus of this project was to test and compare six advanced technology heaters and add-on devices, along with two reference conventional stoves, for energy efficiency, creosote accumulation, and emissions. The appliances were selected, with the assistance of a panel of experts, for their anticipated technical performance and potential market penetration in New York State. The wood heaters and add-on devices based on catalytic combustors performed especially well. Compared to the reference closed stove, the better catalytic stoves consumed up to about 40% less wood to produce the same amount of useful heat, and resulted in about 90% less creosote accumulation and about 70% to 90% less emissions. Equally impressive was the fact that these systems performed very well at all burn rates, including very low burn rates. The catalytic add-on devices exhibited lesser but still significantly improved performance. This project also included tests of some operator variables, efficiency testing methods, and some catalytic combustor design variables. 17 figures, 13 tables.

  15. Improved silicon carbide for advanced heat engines

    NASA Technical Reports Server (NTRS)

    Whalen, Thomas J.

    1988-01-01

    This is the third annual technical report for the program entitled, Improved Silicon Carbide for Advanced Heat Engines, for the period February 16, 1987 to February 15, 1988. The objective of the original program was the development of high strength, high reliability silicon carbide parts with complex shapes suitable for use in advanced heat engines. Injection molding is the forming method selected for the program because it is capable of forming complex parts adaptable for mass production on an economically sound basis. The goals of the revised program are to reach a Weibull characteristic strength of 550 MPa (80 ksi) and a Weibull modulus of 16 for bars tested in 4-point loading. Two tasks are discussed: Task 1 which involves materials and process improvements, and Task 2 which is a MOR bar matrix to improve strength and reliability. Many statistically designed experiments were completed under task 1 which improved the composition of the batches, the mixing of the powders, the sinter and anneal cycles. The best results were obtained by an attritor mixing process which yielded strengths in excess of 550 MPa (80 ksi) and an individual Weibull modulus of 16.8 for a 9-sample group. Strengths measured at 1200 and 1400 C were equal to the room temperature strength. Annealing of machined test bars significantly improved the strength. Molding yields were measured and flaw distributions were observed to follow a Poisson process. The second iteration of the Task 2 matrix experiment is described.

  16. Advanced Electric Traction System Technology Development

    SciTech Connect

    Anderson, Iver

    2011-01-14

    As a subcontractor to General Motors (GM), Ames Laboratory provided the technical expertise and supplied experimental materials needed to assess the technology of high energy bonded permanent magnets that are injection or compression molded for use in the Advanced Electric Traction System motor. This support was a sustained (Phase 1: 6/07 to 3/08) engineering effort that builds on the research achievements of the primary FreedomCAR project at Ames Laboratory on development of high temperature magnet alloy particulate in both flake and spherical powder forms. Ames Lab also provide guidance and direction in selection of magnet materials and supported the fabrication of experimental magnet materials for development of injection molding and magnetization processes by Arnold Magnetics, another project partner. The work with Arnold Magnetics involved a close collaboration on particulate material design and processing to achieve enhanced particulate properties and magnetic performance in the resulting bonded magnets. The overall project direction was provided by GM Program Management and two design reviews were held at GM-ATC in Torrance, CA. Ames Lab utilized current expertise in magnet powder alloy design and processing, along with on-going research advances being achieved under the existing FreedomCAR Program project to help guide and direct work during Phase 1 for the Advanced Electric Traction System Technology Development Program. The technical tasks included review of previous GM and Arnold Magnets work and identification of improvements to the benchmark magnet material, Magnequench MQP-14-12. Other benchmark characteristics of the desired magnet material include 64% volumetric loading with PPS polymer and a recommended maximum use temperature of 200C. A collaborative relationship was maintained with Arnold Magnets on the specification and processing of the bonded magnet material required by GM-ATC.

  17. Advanced electric motor technology flux mapping

    NASA Technical Reports Server (NTRS)

    Doane, George B., III; Campbell, Warren; Dean, Garvin

    1993-01-01

    Design of electric motors which fulfill the needs of Thrust Vector Control (TVC) actuators used in large rocket propelled launch vehicles is covered. To accomplish this end the methodology of design is laid out in some detail. In addition a point design of a motor to fulfill the requirements of a certain actuator specified by MSFC is accomplished and reported upon. In the course of this design great stress has been placed on ridding the actuator of internally generated heat. To conduct the heat out of the motor use is made of the unique properties of the in house MSFC designed driving electronics. This property is that as along as they are operated in a quasi-linear mode the electronics nullify the effects of armature inductance as far as the phase of the armature current versus the rotor position is concerned. Actually the additional inductance due to the extended end turns in this design is of benefit because in the shorted armature failure mode the armature current in the fault (caused by the rotor flux sweeping past the armature) is diminished at a given rotor speed when compared to a more conventional motor with lower inductance. The magnetic circuit is analyzed using electromagnetic finite element methods.

  18. Advances in enhanced heat transfer: 1987

    SciTech Connect

    Jensen, M.K.; Carey, V.P.

    1987-01-01

    This book contains nine selections. Some of the titles are: High Heat-Flux, Forced-Convection Heat Transfer for Tubes with Twisted-Tape Inserts; Heat Transfer Augmentation by Interrupted Surfaces - Experimental Consideration; Turbulent Flow Heat Transfer from Externally Roughened Tubes in Axial Flow in Concentric Pipe Heat Exchangers; and Heat Transfer Enhancement of Turbulent Flow in Pipes with an Internal Circular Rib.

  19. Advanced chemical heat pumps using liquid-vapor reactions

    NASA Astrophysics Data System (ADS)

    Kirol, L.

    Chemical heat pumps utilizing liquid-vapor reactions can be configured in forms analogous to electric drive vapor-compression heat pumps and heat activated absorption heat pumps. Basic thermodynamic considerations eliminate some heat pumps and place restrictive working fluid requirements on others, but two thermodynamically feasible systems have significant potential advantage over conventional technology. An electric drive reactive heat pump can use smaller heat exchangers and compressor than a vapor-compression machine, and have more flexible operating characteristics. A waste heat driven heat pump (temperature amplifier) using liquid-vapor chemical reactions can operate with higher coefficient of performance and smaller heat exchangers than an absorption temperature amplifying heat pump. Higher temperatures and larger temperature lifts should also be possible.

  20. Ceramic technology for advanced heat engines project

    SciTech Connect

    Not Available

    1990-09-01

    The Ceramic Technology for Advanced Heat Engines Project was developed by the Department of Energy's Office of Transportation Systems in Conservation and Renewable Energy. This project was developed to meet the ceramic technology requirements of the OTT's automotive technology programs. This project is managed by ORNL and is closely coordinated with complementary ceramics tasks funded by other DOE offices, NASA, DoD, and industry. Research is discussed under the following topics; Turbomilling of SiC Whiskers; microwave sintering of silicon nitride; and milling characterization; processing of monolithics; silicon nitride matrix; oxide matrix; silicate matrix; thermal and wear coatings; joining; design; contact interfaces; time-dependent behavior; environmental effects; fracture mechanics; nondestructive evaluation; and technology transfer. References, figures, and tables are included with each topic.

  1. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristics of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. These are characterized by specific impulse, overall efficiency, input power, average thrust, power to average thrust ratio and average thrust to dry weight ratio. Several important physical characteristics such as dry system mass, accelerator length, bore size and current pulse requirement are also evaluated in appropriate cases. Only the ion engine can operate at a specific impulse beyond 2000 sec. Rail gun, MPD thruster and free radical thruster are currently characterized by low efficiencies. Mass drivers have the best performance characteristics in terms of overall efficiency, power to average thrust ratio and average thrust to dry weight ratio. But, they can only operate at low specific impulses due to large power requirements and are extremely long due to limitations of driving current. Mercury ion engines have the next best performance characteristics while operating at higher specific impulses. It is concluded that, overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  2. Ceramic technology for Advanced Heat Engines Project

    SciTech Connect

    Johnson, D.R.

    1991-07-01

    Significant accomplishments in fabricating ceramic components for advanced heat engine programs have provided evidence that the operation of ceramic parts in high-temperature engine environments is feasible. However, these programs have also demonstrated that additional research is needed in materials and processing development, design methodology, and database and life prediction before industry will have a sufficient technology base from which to produce reliable cost-effective ceramic engine components commercially. An assessment of needs was completed, and a five year project plan was developed with extensive input from private industry. The project approach includes determining the mechanisms controlling reliability, improving processes for fabricating existing ceramics, developing new materials with increased reliability, and testing these materials in simulated engine environments to confirm reliability. Although this is a generic materials project, the focus is on the structural ceramics for advanced gas turbine and diesel engines, ceramic bearings and attachments, and ceramic coatings for thermal barrier and wear applications in these engines. To facilitate the rapid transfer of this technology to US industry, the major portion of the work is being done in the ceramic industry, with technological support from government laboratories, other industrial laboratories, and universities. This project is managed by ORNL for the Office of Transportation Technologies, Office of Transportation Materials, and is closely coordinated with complementary ceramics tasks funded by other DOE offices, NASA, DOD, and industry.

  3. Waste Heat Recovery from High Temperature Off-Gases from Electric Arc Furnace

    SciTech Connect

    Nimbalkar, Sachin U; Thekdi, Arvind; Keiser, James R; Storey, John Morse

    2014-01-01

    This article presents a study and review of available waste heat in high temperature Electric Arc Furnace (EAF) off gases and heat recovery techniques/methods from these gases. It gives details of the quality and quantity of the sensible and chemical waste heat in typical EAF off gases, energy savings potential by recovering part of this heat, a comprehensive review of currently used waste heat recovery methods and potential for use of advanced designs to achieve a much higher level of heat recovery including scrap preheating, steam production and electric power generation. Based on our preliminary analysis, currently, for all electric arc furnaces used in the US steel industry, the energy savings potential is equivalent to approximately 31 trillion Btu per year or 32.7 peta Joules per year (approximately $182 million US dollars/year). This article describes the EAF off-gas enthalpy model developed at Oak Ridge National Laboratory (ORNL) to calculate available and recoverable heat energy for a given stream of exhaust gases coming out of one or multiple EAF furnaces. This Excel based model calculates sensible and chemical enthalpy of the EAF off-gases during tap to tap time accounting for variation in quantity and quality of off gases. The model can be used to estimate energy saved through scrap preheating and other possible uses such as steam generation and electric power generation using off gas waste heat. This article includes a review of the historical development of existing waste heat recovery methods, their operations, and advantages/limitations of these methods. This paper also describes a program to develop and test advanced concepts for scrap preheating, steam production and electricity generation through use of waste heat recovery from the chemical and sensible heat contained in the EAF off gases with addition of minimum amount of dilution or cooling air upstream of pollution control equipment such as bag houses.

  4. High thermal power density heat transfer apparatus providing electrical isolation at high temperature using heat pipes

    NASA Technical Reports Server (NTRS)

    Morris, J. F. (Inventor)

    1985-01-01

    This invention is directed to transferring heat from an extremely high temperature source to an electrically isolated lower temperature receiver. The invention is particularly concerned with supplying thermal power to a thermionic converter from a nuclear reactor with electric isolation. Heat from a high temperature heat pipe is transferred through a vacuum or a gap filled with electrically nonconducting gas to a cooler heat pipe. If the receiver requires gratr thermal power density, geometries are used with larger heat pipe areas for transmitting and receiving energy than the area for conducting the heat to the thermionic converter. In this way the heat pipe capability for increasing thermal power densities compensates for the comparative low thermal power densities through the electrically nonconducting gap between the two heat pipes.

  5. High thermal power density heat transfer apparatus providing electrical isolation at high temperature using heat pipes

    NASA Astrophysics Data System (ADS)

    Morris, J. F.

    1985-03-01

    This invention is directed to transferring heat from an extremely high temperature source to an electrically isolated lower temperature receiver. The invention is particularly concerned with supplying thermal power to a thermionic converter from a nuclear reactor with electric isolation. Heat from a high temperature heat pipe is transferred through a vacuum or a gap filled with electrically nonconducting gas to a cooler heat pipe. If the receiver requires gratr thermal power density, geometries are used with larger heat pipe areas for transmitting and receiving energy than the area for conducting the heat to the thermionic converter. In this way the heat pipe capability for increasing thermal power densities compensates for the comparative low thermal power densities through the electrically nonconducting gap between the two heat pipes.

  6. Advanced heat exchanger development for molten salts

    DOE PAGES

    Sabharwall, Piyush; Clark, Denis; Glazoff, Michael; ...

    2014-12-01

    This study addresses present work concerned with advanced heat exchanger development for molten salt in nuclear and non nuclear thermal systems. The molten salt systems discussed herein use alloys, such as Hastelloy N and 242, which show corrosion resistance to molten salt at nominal operating temperatures up to 700°C. These alloys were diffusion welded, and the corresponding information is presented. Test specimens were prepared for exposing diffusion welds to molten salt environments. Hastelloy N and 242 were found to be weldable by diffusion welding, with ultimate tensile strengths about 90% of base metal values. Both diffusion welds and sheet materialmore » in Hastelloy N were corrosion tested in?58 mol% KF and 42 mol% ZrF4 at 650, 700, and 850°C for 200, 500, and 1,000 hours. Corrosion rates found were similar between welded and nonwelded materials, typically <10 mils per year. For materials of construction, nickel and alloys with dense nickel coatings are effectively inert to corrosion in fluorides, but not so in chlorides. Hence, additional testing of selected alloys for resistance to intergranular corrosion is needed, as is a determination of corrosion rate as a function of contaminant type and alloy composition with respect to chromium and carbon to better define the optimal chromium and carbon composition, independent of galvanic or differential solubility effects. Also presented is the division of the nuclear reactor and high temperature components per ASME standards, along with design requirements for a subcritical Rankine power cycle heat exchanger that has to overcome pressure difference of about 17 MPa.« less

  7. Advanced heat exchanger development for molten salts

    SciTech Connect

    Sabharwall, Piyush; Clark, Denis; Glazoff, Michael; Zheng, Guiqiu; Sridharan, Kumar; Anderson, Mark

    2014-12-01

    This study addresses present work concerned with advanced heat exchanger development for molten salt in nuclear and non nuclear thermal systems. The molten salt systems discussed herein use alloys, such as Hastelloy N and 242, which show corrosion resistance to molten salt at nominal operating temperatures up to 700°C. These alloys were diffusion welded, and the corresponding information is presented. Test specimens were prepared for exposing diffusion welds to molten salt environments. Hastelloy N and 242 were found to be weldable by diffusion welding, with ultimate tensile strengths about 90% of base metal values. Both diffusion welds and sheet material in Hastelloy N were corrosion tested in?58 mol% KF and 42 mol% ZrF4 at 650, 700, and 850°C for 200, 500, and 1,000 hours. Corrosion rates found were similar between welded and nonwelded materials, typically <10 mils per year. For materials of construction, nickel and alloys with dense nickel coatings are effectively inert to corrosion in fluorides, but not so in chlorides. Hence, additional testing of selected alloys for resistance to intergranular corrosion is needed, as is a determination of corrosion rate as a function of contaminant type and alloy composition with respect to chromium and carbon to better define the optimal chromium and carbon composition, independent of galvanic or differential solubility effects. Also presented is the division of the nuclear reactor and high temperature components per ASME standards, along with design requirements for a subcritical Rankine power cycle heat exchanger that has to overcome pressure difference of about 17 MPa.

  8. Advanced technology options for industrial heating equipment research

    SciTech Connect

    Jain, R.C.

    1992-10-01

    This document presents a strategy for a comprehensive program plan that is applicable to the Combustion Equipment Program of the DOE Office of Industrial Technologies (the program). The program seeks to develop improved heating equipment and advanced control techniques which, by improvements in combustion and beat transfer, will increase energy-use efficiency and productivity in industrial processes and allow the preferred use of abundant, low grade and waste domestic fuels. While the plan development strategy endeavors to be consistent with the programmatic goals and policies of the office, it is primarily governed by the needs and concerns of the US heating equipment industry. The program, by nature, focuses on energy intensive industrial processes. According to the DOE Manufacturing Energy Consumption Survey (MECS), the industrial sector in the US consumed about 21 quads of energy in 1988 in the form of coal, petroleum, natural gas and electricity. This energy was used as fuels for industrial boilers and furnaces, for agricultural uses, for construction, as feedstocks for chemicals and plastics, and for steel, mining, motors, engines and other industrial use over 75 percent of this energy was consumed to provide heat and power for manufacturing industries. The largest consumers of fuel energy were the primary metals, chemical and allied products, paper and allied products, and stone, clay and glass industry groups which accounted for about 60% of the total fuel energy consumed by the US manufacturing sector.

  9. Improving Heat Pump Water Heater Effeciency by Avoiding Electric Resistance Heater Use

    SciTech Connect

    Boudreaux, Philip R.; Munk, Jeffrey D.; Jackson, Roderick K.; Gehl, Anthony C.; Parkison, April E.; Nutaro, James J.

    2014-09-01

    Heat pump water heaters (HPWHs) are a promising technology that can decrease the domestic hot water energy consumption over an electric resistance storage water heater by up to 50%. Heat pump water heaters are really two water heaters in one; they can heat water by using a heat pump or by using electric resistance elements. During large water draw events the HPWHs will use the resistance elements that decrease the overall efficiency of the units. ORNL proposed and tested an advanced control algorithm that anticipates the large water draw events and appropriately sets-up the temperature of the tank water using only the heat pump. With sufficient energy stored in the tank at the elevated temperature, the large water draw is provided for and electric resistance use is avoided. Simulations using a validated heat pump water heater model, and measured water draw data from 25 homes, show average yearly energy savings of 9% for the advanced control algorithm. If the advanced control algorithm perfectly predicts the large water draw events then the savings increase to 19%. This discrepancy could be due to a lack of predictability of water draw patterns in some homes, or the water draw forecasting algorithm could be improved.

  10. Improved silicon carbide for advanced heat engines

    NASA Technical Reports Server (NTRS)

    Whalen, Thomas J.

    1989-01-01

    The development of high strength, high reliability silicon carbide parts with complex shapes suitable for use in advanced heat engines is studied. Injection molding was the forming method selected for the program because it is capable of forming complex parts adaptable for mass production on an economically sound basis. The goals were to reach a Weibull characteristic strength of 550 MPa (80 ksi) and a Weibull modulus of 16 for bars tested in four-point loading. Statistically designed experiments were performed throughout the program and a fluid mixing process employing an attritor mixer was developed. Compositional improvements in the amounts and sources of boron and carbon used and a pressureless sintering cycle were developed which provided samples of about 99 percent of theoretical density. Strengths were found to improve significantly by annealing in air. Strengths in excess of 550 MPa (80 ksi) with Weibull modulus of about 9 were obtained. Further improvements in Weibull modulus to about 16 were realized by proof testing. This is an increase of 86 percent in strength and 100 percent in Weibull modulus over the baseline data generated at the beginning of the program. Molding yields were improved and flaw distributions were observed to follow a Poisson process. Magic angle spinning nuclear magnetic resonance spectra were found to be useful in characterizing the SiC powder and the sintered samples. Turbocharger rotors were molded and examined as an indication of the moldability of the mixes which were developed in this program.

  11. Improved silicon nitride for advanced heat engines

    NASA Technical Reports Server (NTRS)

    Yeh, Hun C.; Fang, Ho T.

    1987-01-01

    The technology base required to fabricate silicon nitride components with the strength, reliability, and reproducibility necessary for actual heat engine applications is presented. Task 2 was set up to develop test bars with high Weibull slope and greater high temperature strength, and to conduct an initial net shape component fabrication evaluation. Screening experiments were performed in Task 7 on advanced materials and processing for input to Task 2. The technical efforts performed in the second year of a 5-yr program are covered. The first iteration of Task 2 was completed as planned. Two half-replicated, fractional factorial (2 sup 5), statistically designed matrix experiments were conducted. These experiments have identified Denka 9FW Si3N4 as an alternate raw material to GTE SN502 Si3N4 for subsequent process evaluation. A detailed statistical analysis was conducted to correlate processing conditions with as-processed test bar properties. One processing condition produced a material with a 97 ksi average room temperature MOR (100 percent of goal) with 13.2 Weibull slope (83 percent of goal); another condition produced 86 ksi (6 percent over baseline) room temperature strength with a Weibull slope of 20 (125 percent of goal).

  12. Low-Heat-Leak Electrical Leads For Cryogenic Systems

    NASA Technical Reports Server (NTRS)

    Wise, Stephanie A.; Hooker, Matthew W.

    1994-01-01

    Electrical leads offering high electrical conductivity and low thermal conductivity developed for use in connecting electronic devices inside cryogenic systems to power supplies, signal-processing circuits, and other circuitry located in nearby warmer surroundings. Strip of superconductive leads on ceramic substrate, similar to ribbon cable, connects infrared detectors at temperature of liquid helium with warmer circuitry. Electrical leads bridging thermal gradient at boundary of cryogenic system designed both to minimize conduction of heat from surroundings through leads into system and to minimize resistive heating caused by electrical currents flowing in leads.

  13. Heat pipe heat rejection system. [for electrical batteries

    NASA Technical Reports Server (NTRS)

    Kroliczek, E. J.

    1976-01-01

    A prototype of a battery heat rejection system was developed which uses heat pipes for more efficient heat removal and for temperature control of the cells. The package consists of five thermal mock-ups of 100 amp-hr prismatic cells. Highly conductive spacers fabricated from honeycomb panels into which heat pipes are embedded transport the heat generated by the cells to the edge of the battery. From there it can be either rejected directly to a cold plate or the heat flow can be controlled by means of two variable conductance heat pipes. The thermal resistance between the interior of the cells and the directly attached cold plate was measured to be 0.08 F/Watt for the 5-cell battery. Compared to a conductive aluminum spacer of equal weight the honeycomb/heat pipe spacer has approximately one-fifth of the thermal resistance. In addition, the honeycomb/heat pipe spacer virtually eliminates temperature gradients along the cells.

  14. Secondary Heat Exchanger Design and Comparison for Advanced High Temperature Reactor

    SciTech Connect

    Piyush Sabharwall; Ali Siahpush; Michael McKellar; Michael Patterson; Eung Soo Kim

    2012-06-01

    The goals of next generation nuclear reactors, such as the high temperature gas-cooled reactor and advance high temperature reactor (AHTR), are to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. The need for efficiency, compactness, and safety challenge the boundaries of existing heat exchanger technology, giving rise to the following study. Various studies have been performed in attempts to update the secondary heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more efficient conversion cycles, such as the Rankine super critical and subcritical cycles. This study considers two different types of heat exchangers—helical coiled heat exchanger and printed circuit heat exchanger—as possible options for the AHTR secondary heat exchangers with the following three different options: (1) A single heat exchanger transfers all the heat (3,400 MW(t)) from the intermediate heat transfer loop to the power conversion system or process plants; (2) Two heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants, each exchanger transfers 1,700 MW(t) with a parallel configuration; and (3) Three heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants. Each heat exchanger transfers 1,130 MW(t) with a parallel configuration. A preliminary cost comparison will be provided for all different cases along with challenges and recommendations.

  15. Techniques to reduce adjacent bed heating in electric reservoir heating processes

    SciTech Connect

    Harvey, A.H.

    1980-12-01

    The feasibility of several enhanced recovery techniques that employ an alternating electric current to heat an oil reservoir, which would act as a resistance heating element, was examined. In these processes, the flow of electric current in formations adjacent to the reservoir could be reduced either by displacing most of the connate water with a more saline water prior to heating, or by establishing a horizontal, electrically conductive fracture within the reservoir. Radial models are proposed for approximating the distribution of resistance heating which would occur.

  16. Spacecraft Impacts with Advanced Power and Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Mason, Lee S.; Oleson, Steven R.

    2000-01-01

    A study was performed to assess the benefits of advanced power and electric propulsion systems for various space missions. Advanced power technologies that were considered included multiband gap and thin-film solar arrays, lithium batteries, and flywheels. Electric propulsion options included Hall effect thrusters and Ion thrusters. Several mission case studies were selected as representative of future applications for advanced power and propulsion systems. These included a low altitude Earth science satellite, a LEO communications constellation, a GEO military surveillance satellite, and a Mercury planetary mission. The study process entailed identification of overall mission performance using state-of-the-art power and propulsion technology, enhancements made possible with either power or electric propulsion advances individually, and the collective benefits realized when advanced power and electric propulsion are combined. Impacts to the overall spacecraft included increased payload, longer operational life, expanded operations and launch vehicle class step-downs.

  17. Overview on NASA's Advanced Electric Propulsion Concepts Activities

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1999-01-01

    Advanced electric propulsion research activities are currently underway that seek to addresses feasibility issues of a wide range of advanced concepts, and may result in the development of technologies that will enable exciting new missions within our solar system and beyond. Each research activity is described in terms of the present focus and potential future applications. Topics include micro-electric thrusters, electrodynamic tethers, high power plasma thrusters and related applications in materials processing, variable specific impulse plasma thrusters, pulsed inductive thrusters, computational techniques for thruster modeling, and advanced electric propulsion missions and systems studies.

  18. Advanced Thermoelectric Materials for Efficient Waste Heat Recovery in Process Industries

    SciTech Connect

    Adam Polcyn; Moe Khaleel

    2009-01-06

    The overall objective of the project was to integrate advanced thermoelectric materials into a power generation device that could convert waste heat from an industrial process to electricity with an efficiency approaching 20%. Advanced thermoelectric materials were developed with figure-of-merit ZT of 1.5 at 275 degrees C. These materials were not successfully integrated into a power generation device. However, waste heat recovery was demonstrated from an industrial process (the combustion exhaust gas stream of an oxyfuel-fired flat glass melting furnace) using a commercially available (5% efficiency) thermoelectric generator coupled to a heat pipe. It was concluded that significant improvements both in thermoelectric material figure-of-merit and in cost-effective methods for capturing heat would be required to make thermoelectric waste heat recovery viable for widespread industrial application.

  19. Carbon Fibers for Electrically Heated System

    DTIC Science & Technology

    1975-05-01

    evaluated by several techniques. Samples of the yarn and fabric were enclosed in clean polyethylene bags which were subsequently heat-seaied and tumbled in...a home clothes dryer without heat. The result- of this test on PVA-sized polyacrylonitrile and rayon precursor yarn and PAN and rayon based fabrics...fabrics which were treated with PVA showed little or no accumulation of carbon/graphite dust within the sealed bag after an hour of tumbling , Fabrics

  20. Advanced Power Electronics and Electric Motors Annual Report -- 2013

    SciTech Connect

    Narumanchi, S.; Bennion, K.; DeVoto, D.; Moreno, G.; Rugh, J.; Waye, S.

    2015-01-01

    This report describes the research into advanced liquid cooling, integrated power module cooling, high temperature air cooled power electronics, two-phase cooling for power electronics, and electric motor thermal management by NREL's Power Electronics group in FY13.

  1. Thermal Storage System for Electric Vehicle Cabin Heating Component and System Analysis

    SciTech Connect

    LaClair, Tim J; Gao, Zhiming; Abdelaziz, Omar; Wang, Mingyu; WolfeIV, Edward; Craig, Timothy

    2016-01-01

    Cabin heating of current electric vehicle (EV) designs is typically provided using electrical energy from the traction battery, since waste heat is not available from an engine as in the case of a conventional automobile. In very cold climatic conditions, the power required for space heating of an EV can be of a similar magnitude to that required for propulsion of the vehicle. As a result, its driving range can be reduced very significantly during the winter season, which limits consumer acceptance of EVs and results in increased battery costs to achieve a minimum range while ensuring comfort to the EV driver. To minimize the range penalty associated with EV cabin heating, a novel climate control system that includes thermal energy storage from an advanced phase change material (PCM) has been designed for use in EVs and plug-in hybrid electric vehicles (PHEVs). The present paper focuses on the modeling and analysis of this electrical PCM-Assisted Thermal Heating System (ePATHS) and is a companion to the paper Design and Testing of a Thermal Storage System for Electric Vehicle Cabin Heating. A detailed heat transfer model was developed to simulate the PCM heat exchanger that is at the heart of the ePATHS and was subsequently used to analyze and optimize its design. The results from this analysis were integrated into a MATLAB Simulink system model to simulate the fluid flow, pressure drop and heat transfer in all components of the ePATHS. The system model was then used to predict the performance of the climate control system in the vehicle and to evaluate control strategies needed to achieve the desired temperature control in the cabin. The analysis performed to design the ePATHS is described in detail and the system s predicted performance in a vehicle HVAC system is presented.

  2. MEMS CLOSED CHAMBER HEAT ENGINE AND ELECTRIC GENERATOR

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A. (Inventor)

    2005-01-01

    A heat engine, preferably combined with an electric generator, and advantageously implemented using micro-electromechanical system (MEMS) technologies as an array of one or more individual heat engine/generators. The heat engine is based on a closed chamber containing a motive medium, preferably a gas; means for alternately enabling and disabling transfer of thermal energy from a heat source to the motive medium; and at least one movable side of the chamber that moves in response to thermally-induced expansion and contraction of the motive medium, thereby converting thermal energy to oscillating movement. The electrical generator is combined with the heat engine to utilize movement of the movable side to convert mechanical work to electrical energy, preferably using electrostatic interaction in a generator capacitor. Preferably at least one heat transfer side of the chamber is placed alternately into and out of contact with the heat source by a motion capacitor, thereby alternately enabling and disabling conductive transfer of heat to the motive medium.

  3. Advanced heat pump cycle. Final performance report

    SciTech Connect

    Groll, E.A.; Radermacher, R.

    1993-07-01

    The desorption and absorption process of a vapor compression heat pump with a solution circuit (VCHSC) proceeds at gliding temperature intervals, which can be adjusted over a wide range. In case that the gliding temperature intervals in the desorber and the absorber overlap, a modification of the VCHSC employing a desorber/absorber heat exchange (DAHX) can be introduced, which results in an extreme reduction of the pressure ratio. Although the DAHX-cycle has features of a two-stage cycle, it still requires only one solution pump, one separator and one compressor. Such a cycle for the working pair ammonia/water is built in the Energy Laboratory of the Center for Environmental Energy Engineering at the University of Maryland. The experimental results obtained with the research plant are discussed and compared to those calculated with a simulation program. The possible temperature lift between heat source and heat sink depending on the achievable COP are presented.

  4. Generator powered electrically heated diesel particulate filter

    DOEpatents

    Gonze, Eugene V; Paratore, Jr., Michael J

    2014-03-18

    A control circuit for a vehicle powertrain includes a switch that selectivity interrupts current flow between a first terminal and a second terminal. A first power source provides power to the first terminal and a second power source provides power to the second terminal and to a heater of a heated diesel particulate filter (DPF). The switch is opened during a DPF regeneration cycle to prevent the first power source from being loaded by the heater while the heater is energized.

  5. Design and Testing of a Thermal Storage System for Electric Vehicle Cabin Heating

    SciTech Connect

    Wang, Mingyu; WolfeIV, Edward; Craig, Timothy; LaClair, Tim J; Gao, Zhiming; Abdelaziz, Omar

    2016-01-01

    Without the waste heat available from the engine of a conventional automobile, electric vehicles (EVs) must provide heat to the cabin for climate control using energy stored in the vehicle. In current EV designs, this energy is typically provided by the traction battery. In very cold climatic conditions, the power required to heat the EV cabin can be of a similar magnitude to that required for propulsion of the vehicle. As a result, the driving range of an EV can be reduced very significantly during winter months, which limits consumer acceptance of EVs and results in increased battery costs to achieve a minimum range while ensuring comfort to the EV driver. To minimize the range penalty associated with EV cabin heating, a novel climate control system that includes thermal energy storage has been designed for use in EVs and plug-in hybrid electric vehicles (PHEVs). The system uses the stored latent heat of an advanced phase change material (PCM) to provide cabin heating. The PCM is melted while the EV is connected to the electric grid for charging of the electric battery, and the stored energy is subsequently transferred to the cabin during driving. To minimize thermal losses when the EV is parked for extended periods, the PCM is encased in a high performance insulation system. The electrical PCM-Assisted Thermal Heating System (ePATHS) was designed to provide enough thermal energy to heat the EV s cabin for approximately 46 minutes, covering the entire daily commute of a typical driver in the U.S.

  6. Advanced batteries for electric vehicle applications

    SciTech Connect

    Henriksen, G.L.

    1993-08-01

    A technology assessment is given for electric batteries with potential for use in electric powered vehicles. Parameters considered include: specific energy, specific power, energy density, power density, cycle life, service life, recharge time, and selling price. Near term batteries include: nickel/cadmium and lead-acid batteries. Mid term batteries include: sodium/sulfur, sodium/nickel chloride, nickel/metal hydride, zinc/air, zinc/bromine, and nickel/iron systems. Long term batteries include: lithium/iron disulfide and lithium- polymer systems. Performance and life testing data for these systems are discussed. (GHH)

  7. Thermal treatment of low permeability soils using electrical resistance heating

    SciTech Connect

    Udell, K.S.

    1996-08-01

    The acceleration of recovery rates of second phase liquid contaminants from the subsurface during gas or water pumping operations is realized by increasing the soil and ground water temperature. Electrical heating with AC current is one method of increasing the soil and groundwater temperature and has particular applicability to low permeability soils. Several mechanisms have been identified that account for the enhanced removal of the contaminants during electrical heating. These are vaporization of liquid contaminants with low boiling points, temperature-enhanced evaporation rates of semi-volatile components, and removal of residual contaminants by the boiling of residual water. Field scale studies of electrical heating and fluid extraction show the effectiveness of this technique and its applicability to contaminants found both above and below the water table and within low permeability soils. 10 refs., 8 figs.

  8. Advanced Cooling for High Power Electric Actuators.

    DTIC Science & Technology

    1998-10-01

    Winding Temperature Response 2.3-7 3.1.1-1 Reflux/PCM Design Concept 3.1.1-2 Typical Loading Percentage for Spoiler Electromotor -Actuator 3.1.2-1...for a switched reluctance electromotor that is to be used in the spoiler of a large aircraft. A cooler was designed to dissipate over 850 W of heat...Loading Percentage for Spoiler Electromotor -Actuator 0162ms Page 3-2 3.1.2 Small Cooler Design Problem Definition The heat exchanger was designed

  9. Advanced Heat Transfer and Thermal Storage Fluids

    SciTech Connect

    Moens, L.; Blake, D.

    2005-01-01

    The design of the next generation solar parabolic trough systems for power production will require the development of new thermal energy storage options with improved economics or operational characteristics. Current heat-transfer fluids such as VP-1?, which consists of a eutectic mixture of biphenyl and diphenyl oxide, allow a maximum operating temperature of ca. 300 C, a limit above which the vapor pressure would become too high and would require pressure-rated tanks. The use of VP-1? also suffers from a freezing point around 13 C that requires heating during cold periods. One of the goals for future trough systems is the use of heat-transfer fluids that can act as thermal storage media and that allow operating temperatures around 425 C combined with lower limits around 0 C. This paper presents an outline of our latest approach toward the development of such thermal storage fluids.

  10. Iron aluminide useful as electrical resistance heating elements

    DOEpatents

    Sikka, V.K.; Deevi, S.C.; Fleischhauer, G.S.; Hajaligol, M.R.; Lilly, A.C. Jr.

    1997-04-15

    The invention relates generally to aluminum containing iron-base alloys useful as electrical resistance heating elements. The aluminum containing iron-base alloys have improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The alloy has an entirely ferritic microstructure which is free of austenite and includes, in weight %, over 4% Al, {<=}1% Cr and either {>=}0.05% Zr or ZrO{sub 2} stringers extending perpendicular to an exposed surface of the heating element or {>=}0.1% oxide dispersoid particles. The alloy can contain 14-32% Al, {<=}2% Ti, {<=}2% Mo, {<=}1% Zr, {<=}1% C, {<=}0.1% B, {<=}30% oxide dispersoid and/or electrically insulating or electrically conductive covalent ceramic particles, {<=}1% rare earth metal, {<=}1% oxygen, {<=}3% Cu, balance Fe. 64 figs.

  11. Iron aluminide useful as electrical resistance heating elements

    DOEpatents

    Sikka, Vinod K.; Deevi, Seetharama C.; Fleischhauer, Grier S.; Hajaligol, Mohammad R.; Lilly, Jr., A. Clifton

    2001-01-01

    The invention relates generally to aluminum containing iron-base alloys useful as electrical resistance heating elements. The aluminum containing iron-base alloys have improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The alloy has an entirely ferritic microstructure which is free of austenite and includes, in weight %, over 4% Al, .ltoreq.1% Cr and either .gtoreq.0.05% Zr or ZrO.sub.2 stringers extending perpendicular to an exposed surface of the heating element or .gtoreq.0.1% oxide dispersoid particles. The alloy can contain 14-32% Al, .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Zr, .ltoreq.1% C, .ltoreq.0.1% B, .ltoreq.30% oxide dispersoid and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, .ltoreq.1% oxygen, .ltoreq.3% Cu, balance Fe.

  12. Iron aluminide useful as electrical resistance heating elements

    DOEpatents

    Sikka, Vinod K.; Deevi, Seetharama C.; Fleischhauer, Grier S.; Hajaligol, Mohammad R.; Lilly, Jr., A. Clifton

    1997-01-01

    The invention relates generally to aluminum containing iron-base alloys useful as electrical resistance heating elements. The aluminum containing iron-base alloys have improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The alloy has an entirely ferritic microstructure which is free of austenite and includes, in weight %, over 4% Al, .ltoreq.1% Cr and either .gtoreq.0.05% Zr or ZrO.sub.2 stringers extending perpendicular to an exposed surface of the heating element or .gtoreq.0.1% oxide dispersoid particles. The alloy can contain 14-32% Al, .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Zr, .ltoreq.1% C, .ltoreq.0.1% B, .ltoreq.30% oxide dispersoid and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, .ltoreq.1% oxygen, .ltoreq.3% Cu, balance Fe.

  13. Iron aluminide useful as electrical resistance heating elements

    DOEpatents

    Sikka, Vinod K.; Deevi, Seetharama C.; Fleischhauer, Grier S.; Hajaligol, Mohammad R.; Lilly, Jr., A. Clifton

    1999-01-01

    The invention relates generally to aluminum containing iron-base alloys useful as electrical resistance heating elements. The aluminum containing iron-base alloys have improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The alloy has an entirely ferritic microstructure which is free of austenite and includes, in weight %, over 4% Al, .ltoreq.1% Cr and either .gtoreq.0.05% Zr or ZrO.sub.2 stringers extending perpendicular to an exposed surface of the heating element or .gtoreq.0.1% oxide dispersoid particles. The alloy can contain 14-32% Al, .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Zr, .ltoreq.1% C, .ltoreq.0.1% B, .ltoreq.30% oxide dispersoid and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, .ltoreq.1% oxygen, .ltoreq.3% Cu, balance Fe.

  14. Non-joule heating of ice in an electric field.

    PubMed

    Petrenko, Victor F; Ryzhkin, Ivan A

    2011-06-16

    We theoretically predict and calculate non-Joule heating/cooling caused by a direct electric current in ordinary crystalline ice Ih. The cause of this effect is related to partial ordering/disordering occurring in the proton subsystem of ice when protons either drift or diffuse in the ice. Depending on relative directions of the electric current and the configuration vector of ice, the non-Joule effect can be either positive, that is, heat generation, or negative, that is, heat absorption, and its absolute magnitude is usually comparable with that of normal Joule heating. The magnitude of this phenomenon is also approximately inversely proportional to the ice temperature and, thus, is more pronounced at low temperatures.

  15. Climate, extreme heat, and electricity demand in California

    SciTech Connect

    Miller, N.L.; Hayhoe, K.; Jin, J.; Auffhammer, M.

    2008-04-01

    Climate projections from three atmosphere-ocean climate models with a range of low to mid-high temperature sensitivity forced by the Intergovernmental Panel for Climate Change SRES higher, middle, and lower emission scenarios indicate that, over the 21st century, extreme heat events for major cities in heavily air-conditioned California will increase rapidly. These increases in temperature extremes are projected to exceed the rate of increase in mean temperature, along with increased variance. Extreme heat is defined here as the 90 percent exceedance probability (T90) of the local warmest summer days under the current climate. The number of extreme heat days in Los Angeles, where T90 is currently 95 F (32 C), may increase from 12 days to as many as 96 days per year by 2100, implying current-day heat wave conditions may last for the entire summer, with earlier onset. Overall, projected increases in extreme heat under the higher A1fi emission scenario by 2070-2099 tend to be 20-30 percent higher than those projected under the lower B1 emission scenario, ranging from approximately double the historical number of days for inland California cities (e.g. Sacramento and Fresno), up to four times for previously temperate coastal cities (e.g. Los Angeles, San Diego). These findings, combined with observed relationships between high temperature and electricity demand for air-conditioned regions, suggest potential shortfalls in transmission and supply during T90 peak electricity demand periods. When the projected extreme heat and peak demand for electricity are mapped onto current availability, maintaining technology and population constant only for demand side calculations, we find the potential for electricity deficits as high as 17 percent. Similar increases in extreme heat days are suggested for other locations across the U.S. southwest, as well as for developing nations with rapidly increasing electricity demands. Electricity response to recent extreme heat events, such

  16. Advanced two-phase heat transfer systems

    NASA Technical Reports Server (NTRS)

    Swanson, Theodore D.

    1992-01-01

    Future large spacecraft, such as the Earth Observing System (EOS) platforms, will require a significantly more capable thermal control system than is possible with current 'passive' technology. Temperatures must be controlled much more tightly over a larger surface area. Numerous heat load sources will often be located inside the body of the spacecraft without a good view to space. Power levels and flux densities may be higher than can be accommodated with traditional technology. Integration and ground testing will almost certainly be much more difficult with such larger, more complex spacecraft. For these and similar reasons, the Goddard Space Flight Center (GSFC) has been developing a new, more capable thermal control technology called capillary pumped loops (CPL's). CPL's represent an evolutionary improvement over heat pipes; they can transport much greater quantities of heat over much longer distances and can serve numerous heat load sources. In addition, CPL's can be fabricated into large cold plates that can be held to tight thermal gradients. Development of this technology began in the early 1980's and is now reaching maturity. CPL's have recently been baselined for the EOS-AM platform (1997 launch) and the COMET spacecraft (1992 launch). This presentation describes this new technology and its applications. Most of the viewgraphs are self descriptive. For those that are less clear additional comments are provided.

  17. Overview of Heat Addition and Efficiency Predictions for an Advanced Stirling Convertor

    NASA Technical Reports Server (NTRS)

    Wilson, Scott D.; Reid, Terry V.; Schifer, Nicholas A.; Briggs, Maxwell H.

    2012-01-01

    The U.S. Department of Energy (DOE) and Lockheed Martin Space Systems Company (LMSSC) have been developing the Advanced Stirling Radioisotope Generator (ASRG) for use as a power system for space science missions. This generator would use two high-efficiency Advanced Stirling Convertors (ASCs), developed by Sunpower Inc. and NASA Glenn Research Center (GRC). The ASCs convert thermal energy from a radioisotope heat source into electricity. As part of ground testing of these ASCs, different operating conditions are used to simulate expected mission conditions. These conditions require achieving a particular operating frequency, hot end and cold end temperatures, and specified electrical power output for a given net heat input. Microporous bulk insulation is used in the ground support test hardware to minimize the loss of thermal energy from the electric heat source to the environment. The insulation package is characterized before operation to predict how much heat will be absorbed by the convertor and how much will be lost to the environment during operation. In an effort to validate these predictions, numerous tasks have been performed, which provided a more accurate value for net heat input into the ASCs. This test and modeling effort included: (a) making thermophysical property measurements of test setup materials to provide inputs to the numerical models, (b) acquiring additional test data that was collected during convertor tests to provide numerical models with temperature profiles of the test setup via thermocouple and infrared measurements, (c) using multidimensional numerical models (computational fluid dynamics code) to predict net heat input of an operating convertor, and (d) using validation test hardware to provide direct comparison of numerical results and validate the multidimensional numerical models used to predict convertor net heat input. This effort produced high fidelity ASC net heat input predictions, which were successfully validated using

  18. ARPA-E: Advancing the Electric Grid

    SciTech Connect

    Lemmon, John; Ruiz, Pablo; Sommerer, Tim; Aziz, Michael

    2014-02-24

    The electric grid was designed with the assumption that all energy generation sources would be relatively controllable, and grid operators would always be able to predict when and where those sources would be located. With the addition of renewable energy sources like wind and solar, which can be installed faster than traditional generation technologies, this is no longer the case. Furthermore, the fact that renewable energy sources are imperfectly predictable means that the grid has to adapt in real-time to changing patterns of power flow. We need a dynamic grid that is far more flexible. This video highlights three ARPA-E-funded approaches to improving the grid's flexibility: topology control software from Boston University that optimizes power flow, gas tube switches from General Electric that provide efficient power conversion, and flow batteries from Harvard University that offer grid-scale energy storage.

  19. ARPA-E: Advancing the Electric Grid

    ScienceCinema

    Lemmon, John; Ruiz, Pablo; Sommerer, Tim; Aziz, Michael

    2016-07-12

    The electric grid was designed with the assumption that all energy generation sources would be relatively controllable, and grid operators would always be able to predict when and where those sources would be located. With the addition of renewable energy sources like wind and solar, which can be installed faster than traditional generation technologies, this is no longer the case. Furthermore, the fact that renewable energy sources are imperfectly predictable means that the grid has to adapt in real-time to changing patterns of power flow. We need a dynamic grid that is far more flexible. This video highlights three ARPA-E-funded approaches to improving the grid's flexibility: topology control software from Boston University that optimizes power flow, gas tube switches from General Electric that provide efficient power conversion, and flow batteries from Harvard University that offer grid-scale energy storage.

  20. Advanced Heat Pipes For Optical Applications

    NASA Astrophysics Data System (ADS)

    Shaubach, Robert M.; Eastman, G. Yale

    1984-12-01

    Heat pipes offer the potential of vibrationless cooling of optical surfaces while maintaining a high degree of temperature uniformity on the cooled surface. The objective of the present program is to develop and demonstrate prototype heat pipes for this application. The material of construction is silicon; the pqwer density range is 5 to 50 Watts/per square centimeter with a nominal objective of 30 W/cm2. This paper describes the first eighteen months of work, during which the contract goals were met. The program was carried out by Thermacore on Contract F33615-82-C-5127 for the Department of the Air Force, Aeronautical Systems Division, Wright-Patterson Air Force Base, Ohio. Dr. Alan K. Hopkins of the Materials Laboratory supplied technical supervision of the program for the Air Force.

  1. Energy Conversion Advanced Heat Transport Loop and Power Cycle

    SciTech Connect

    Oh, C. H.

    2006-08-01

    The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. Many aspects of the NGNP must be researched and developed in order to make recommendations on the final design of the plant. Parameters such as working conditions, cycle components, working fluids, and power conversion unit configurations must be understood. Three configurations of the power conversion unit were demonstrated in this study. A three-shaft design with 3 turbines and 4 compressors, a combined cycle with a Brayton top cycle and a Rankine bottoming cycle, and a reheated cycle with 3 stages of reheat were investigated. An intermediate heat transport loop for transporting process heat to a High Temperature Steam Electrolysis (HTSE) hydrogen production plant was used. Helium, CO2, and an 80% nitrogen, 20% helium mixture (by weight) were studied to determine the best working fluid in terms cycle efficiency and development cost. In each of these configurations the relative component size were estimated for the different working fluids. The relative size of the turbomachinery was measured by comparing the power input/output of the component. For heat exchangers the volume was computed and compared. Parametric studies away from the baseline values of the three-shaft and combined cycles were performed to determine the effect of varying conditions in the cycle. This gives some insight into the sensitivity of these cycles to various

  2. Evaluation of Advanced Stirling Convertor Net Heat Input Correlation Methods Using a Thermal Standard

    NASA Technical Reports Server (NTRS)

    Briggs, Maxwell H.; Schifer, Nicholas A.

    2012-01-01

    The U.S. Department of Energy (DOE) and Lockheed Martin Space Systems Company (LMSSC) have been developing the Advanced Stirling Radioisotope Generator (ASRG) for use as a power system for space science missions. This generator would use two high-efficiency Advanced Stirling Convertors (ASCs), developed by Sunpower Inc. and NASA Glenn Research Center (GRC). The ASCs convert thermal energy from a radioisotope heat source into electricity. As part of ground testing of these ASCs, different operating conditions are used to simulate expected mission conditions. These conditions require achieving a particular operating frequency, hot end and cold end temperatures, and specified electrical power output for a given net heat input. In an effort to improve net heat input predictions, numerous tasks have been performed which provided a more accurate value for net heat input into the ASCs, including testing validation hardware, known as the Thermal Standard, to provide a direct comparison to numerical and empirical models used to predict convertor net heat input. This validation hardware provided a comparison for scrutinizing and improving empirical correlations and numerical models of ASC-E2 net heat input. This hardware simulated the characteristics of an ASC-E2 convertor in both an operating and non-operating mode. This paper describes the Thermal Standard testing and the conclusions of the validation effort applied to the empirical correlation methods used by the Radioisotope Power System (RPS) team at NASA Glenn.

  3. Technologies for Production of Heat and Electricity

    SciTech Connect

    Jacob J. Jacobson; Kara G. Cafferty

    2014-04-01

    Biomass is a desirable source of energy because it is renewable, sustainable, widely available throughout the world, and amenable to conversion. Biomass is composed of cellulose, hemicellulose, and lignin components. Cellulose is generally the dominant fraction, representing about 40 to 50% of the material by weight, with hemicellulose representing 20 to 50% of the material, and lignin making up the remaining portion [4,5,6]. Although the outward appearance of the various forms of cellulosic biomass, such as wood, grass, municipal solid waste (MSW), or agricultural residues, is different, all of these materials have a similar cellulosic composition. Elementally, however, biomass varies considerably, thereby presenting technical challenges at virtually every phase of its conversion to useful energy forms and products. Despite the variances among cellulosic sources, there are a variety of technologies for converting biomass into energy. These technologies are generally divided into two groups: biochemical (biological-based) and thermochemical (heat-based) conversion processes. This chapter reviews the specific technologies that can be used to convert biomass to energy. Each technology review includes the description of the process, and the positive and negative aspects.

  4. Electrically heated particulate filter diagnostic systems and methods

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2009-09-29

    A system that diagnoses regeneration of an electrically heated particulate filter is provided. The system generally includes a grid module that diagnoses a fault of the grid based on at least one of a current signal and a voltage signal. A diagnostic module at least one of sets a fault status and generates a warning signal based on the fault of the grid.

  5. 46 CFR 169.685 - Electric heating and cooking equipment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... electric space heater for heating rooms and compartments must be provided with thermal cutouts to prevent overheating. Each heater must be so constructed and installed as to prevent the hanging of towels, clothing, etc., on the heater, and to prevent overheating of heater parts and adjacent bulkheads or decks....

  6. Heat pipe radiation cooling of advanced hypersonic propulsion system components

    NASA Technical Reports Server (NTRS)

    Martin, R. A.; Keddy, M.; Merrigan, M. A.; Silverstein, C. C.

    1991-01-01

    Heat transfer, heat pipe, and system studies were performed to assess the newly proposed heat pipe radiation cooling (HPRC) concept. With an HPRC system, heat is removed from the ramburner and nozzle of a hypersonic aircraft engine by a surrounding, high-temperature, heat pipe nacelle structure, transported to nearby external surfaces, and rejected to the environment by thermal radiation. With HPRC, the Mach number range available for using hydrocarbon fuels for aircraft operation extends into the Mach 4 to Mach 6 range, up from the current limit of about Mach 4. Heat transfer studies using a newly developed HPRC computer code determine cooling system and ramburner and nozzle temperatures, heat loads, and weights for a representative combined-cycle engine cruising at Mach 5 at 80,000 ft altitude. Heat pipe heat transport calculations, using the Los Alamos code HTPIPE, reveal that adequate heat trasport capability is available using molybdenum-lithium heat pipe technology. Results show that the HPRC system radiator area is limited in size to the ramburner-nozzle region of the engine nacelle; reasonable system weights are expected; hot section temperatures are consistent with advanced structural materials development goals; and system impact on engine performance is minimal.

  7. Advanced electric propulsion system concept for electric vehicles

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Forbes, F. E.

    1979-01-01

    Seventeen propulsion system concepts for electric vehicles were compared to determine the differences in components and battery pack to achieve the basic performance level. Design tradeoffs were made for selected configurations to find the optimum component characteristics required to meet all performance goals. The anticipated performance when using nickel-zinc batteries rather than the standard lead-acid batteries was also evaluated. The two systems selected for the final conceptual design studies included a system with a flywheel energy storage unit and a basic system that did not have a flywheel. The flywheel system meets the range requirement with either lead-acid or nickel-zinc batteries and also the acceleration of zero to 89 km/hr in 15 s. The basic system can also meet the required performance with a fully charged battery, but, when the battery approaches 20 to 30 percent depth of discharge, maximum acceleration capability gradually degrades. The flywheel system has an estimated life-cycle cost of $0.041/km using lead-acid batteries. The basic system has a life-cycle cost of $0.06/km. The basic system, using batteries meeting ISOA goals, would have a life-cycle cost of $0.043/km.

  8. Integrated exhaust and electrically heated particulate filter regeneration systems

    SciTech Connect

    Gonze, Eugene V.; Paratore, Jr., Michael J.

    2013-01-08

    A system includes a particulate matter (PM) filter that includes multiple zones. An electrical heater includes heater segments that are associated with respective ones of the zones. The electrical heater is arranged upstream from and proximate with the PM filter. A post-fuel injection system injects fuel into at least one of a cylinder of an engine and an exhaust system. A control module is configured to operate in a first mode that includes activating the electrical heater to heat exhaust of the engine. The control module is also configured to operate in a second mode that includes activating the post-injection system to heat the exhaust. The control module selectively operates in at least one of the first mode and the second mode.

  9. Continuously variable transmission: Assessment of applicability to advance electric vehicles

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Parker, R. J.

    1981-01-01

    A brief historical account of the evolution of continuously variable transmissions (CVT) for automotive use is given. The CVT concepts which are potentially suitable for application with electric and hybrid vehicles are discussed. The arrangement and function of several CVT concepts are cited along with their current developmental status. The results of preliminary design studies conducted on four CVT concepts for use in advanced electric vehicles are discussed.

  10. Advanced electric motor technology: Flux mapping

    NASA Technical Reports Server (NTRS)

    Doane, George B., III; Campbell, Warren; Brantley, Larry W.; Dean, Garvin

    1992-01-01

    This report contains the assumptions, mathematical models, design methodology, and design points involved with the design of an electromechanical actuator (EMA) suitable for directing the thrust vector of a large MSFC/NASA launch vehicle. Specifically the design of such an actuator for use on the upcoming liquid fueled National Launch System (NLS) is considered culminating in a point design of both the servo system and the electric motor needed. A major thrust of the work is in selecting spur gear and roller screw reduction ratios to achieve simultaneously wide bandwidth, maximum power transfer, and disturbance rejection while meeting specified horsepower requirements at a given stroking speed as well as a specified maximum stall force. An innovative feedback signal is utilized in meeting these diverse objectives.

  11. Advanced ac powertrain for electric vehicles

    SciTech Connect

    Slicker, J.M.; Kalns, L.

    1985-01-01

    The design of an ac propulsion system for an electric vehicle includes a three-phase induction motor, transistorized PWM inverter/battery charger, microprocessor-based controller, and two-speed automatic transaxle. This system was built and installed in a Mercury Lynx test bed vehicle as part of a Department of Energy propulsion system development program. An integral part of the inverter is a 4-kw battery charger which utilizes one of the bridge transistors. The overall inverter strategy for this configuration is discussed. The function of the microprocessor-based controller is described. Typical test results of the total vehicle and each of its major components are given, including system efficiencies and test track performance results.

  12. Heat pipe cooled heat rejection subsystem modelling for nuclear electric propulsion

    NASA Technical Reports Server (NTRS)

    Moriarty, Michael P.

    1993-01-01

    NASA LeRC is currently developing a FORTRAN based computer model of a complete nuclear electric propulsion (NEP) vehicle that can be used for piloted and cargo missions to the Moon or Mars. Proposed designs feature either a Brayton or a K-Rankine power conversion cycle to drive a turbine coupled with rotary alternators. Both ion and magnetoplasmodynamic (MPD) thrusters will be considered in the model. In support of the NEP model, Rocketdyne is developing power conversion, heat rejection, and power management and distribution (PMAD) subroutines. The subroutines will be incorporated into the NEP vehicle model which will be written by NASA LeRC. The purpose is to document the heat pipe cooled heat rejection subsystem model and its supporting subroutines. The heat pipe cooled heat rejection subsystem model is designed to provide estimate of the mass and performance of the equipment used to reject heat from Brayton and Rankine cycle power conversion systems. The subroutine models the ductwork and heat pipe cooled manifold for a gas cooled Brayton; the heat sink heat exchanger, liquid loop piping, expansion compensator, pump and manifold for a liquid loop cooled Brayton; and a shear flow condenser for a K-Rankine system. In each case, the final heat rejection is made by way of a heat pipe radiator. The radiator is sized to reject the amount of heat necessary.

  13. Heat pipe cooled heat rejection subsystem modelling for nuclear electric propulsion

    NASA Astrophysics Data System (ADS)

    Moriarty, Michael P.

    1993-11-01

    NASA LeRC is currently developing a FORTRAN based computer model of a complete nuclear electric propulsion (NEP) vehicle that can be used for piloted and cargo missions to the Moon or Mars. Proposed designs feature either a Brayton or a K-Rankine power conversion cycle to drive a turbine coupled with rotary alternators. Both ion and magnetoplasmodynamic (MPD) thrusters will be considered in the model. In support of the NEP model, Rocketdyne is developing power conversion, heat rejection, and power management and distribution (PMAD) subroutines. The subroutines will be incorporated into the NEP vehicle model which will be written by NASA LeRC. The purpose is to document the heat pipe cooled heat rejection subsystem model and its supporting subroutines. The heat pipe cooled heat rejection subsystem model is designed to provide estimate of the mass and performance of the equipment used to reject heat from Brayton and Rankine cycle power conversion systems. The subroutine models the ductwork and heat pipe cooled manifold for a gas cooled Brayton; the heat sink heat exchanger, liquid loop piping, expansion compensator, pump and manifold for a liquid loop cooled Brayton; and a shear flow condenser for a K-Rankine system. In each case, the final heat rejection is made by way of a heat pipe radiator. The radiator is sized to reject the amount of heat necessary.

  14. Advanced power electronics and electric machinery program

    SciTech Connect

    None, None

    2007-12-01

    The U.S. Department of Energy (DOE) and the U.S. Council for Automotive Research (composed of automakers Ford, General Motors, and Chrysler) announced in January 2002 a new cooperative research effort. Known as "FreedomCAR" (derived from "Freedom" and "Cooperative Automotive Research"), it represents DOE's commitment to developing public/private partnerships to fund high-risk, high-payoff research into advanced automotive technologies. Efficient fuel cell technology, which uses hydrogen to power automobiles without air pollution, is a very promising pathway to achieving the ultimate vision. The new partnership replaces and builds upon the Partnership for a New Generation of Vehicles initiative that ran from 1993 through 2001.

  15. Performance improvement of optical fiber coupler with electric heating versus gas heating.

    PubMed

    Shuai, Cijun; Gao, Chengde; Nie, Yi; Peng, Shuping

    2010-08-20

    Gas heating has been widely used in the process of fused biconical tapering. However, as the instability and asymmetric flame temperature of gas heating exist, the performance of the optical devices fabricated by this method was affected. To overcome the problems resulting from gas combustion, an electric heater is designed and manufactured using a metal-ceramic (MoSi(2)) as a heating material. Our experimental data show that the fused-taper machine with an electric heater has improved the performance of optical devices by increasing the consistency of the extinction ratio, excess loss, and the splitting ratio over that of the previous gas heating mode. Microcrystallizations and microcracks were observed at the fused region of the polarization-maintaining (PM) fiber coupler and at the taper region with scanning electron microscopy and atomic force microscopy respectively. The distribution of the microcrystallizations and microcracks are nonuniform along the fiber with gas heating, while their distribution is rather uniform with electric heating. These findings show that the novel optical fiber coupler with an electric heater has improved the performance of optical fiber devices by affecting the consistency of the optical parameters and micromorphology of the surface of PM fiber.

  16. Advanced continuously variable transmissions for electric and hybrid vehicles

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.

    1980-01-01

    A brief survey of past and present continuously variable transmissions (CVT) which are potentially suitable for application with electric and hybrid vehicles is presented. Discussion of general transmission requirements and benefits attainable with a CVT for electric vehicle use is given. The arrangement and function of several specific CVT concepts are cited along with their current development status. Lastly, the results of preliminary design studies conducted under a NASA contract for DOE on four CVT concepts for use in advanced electric vehicles are reviewed.

  17. IEA Annex 26: Advanced Supermarket Refrigeration/Heat Recovery Systems

    SciTech Connect

    Baxter, VAN

    2003-05-19

    With increased concern about the impact of refrigerant leakage on global warming, a number of new supermarket refrigeration system configurations requiring significantly less refrigerant charge are being considered. In order to help promote the development of advanced systems and expand the knowledge base for energy-efficient supermarket technology, the International Energy Agency (IEA) established IEA Annex 26 (Advanced Supermarket Refrigeration/Heat Recovery Systems) under the ''IEA Implementing Agreement on Heat Pumping Technologies''. Annex 26 focuses on demonstrating and documenting the energy saving and environmental benefits of advanced systems design for food refrigeration and space heating and cooling for supermarkets. Advanced in this context means systems that use less energy, require less refrigerant and produce lower refrigerant emissions. Stated another way, the goal is to identify supermarket refrigeration and HVAC technology options that reduce the total equivalent warming impact (TEWI) of supermarkets by reducing both system energy use (increasing efficiency) and reducing total refrigerant charge. The Annex has five participating countries: Canada, Denmark, Sweden, the United Kingdom, and the United States. The working program of the Annex has involved analytical and experimental investigation of several candidate system design approaches to determine their potential to reduce refrigerant usage and energy consumption. Advanced refrigeration system types investigated include the following: distributed compressor systems--small parallel compressor racks are located in close proximity to the food display cases they serve thus significantly shortening the connecting refrigerant line lengths; secondary loop systems--one or more central chillers are used to refrigerate a secondary coolant (e.g. brine, ice slurry, or CO2) that is pumped to the food display cases on the sales floor; self-contained display cases--each food display case has its own

  18. Performance of an Advanced Stirling Convertor Based on Heat Flux Sensor Measurements

    NASA Technical Reports Server (NTRS)

    Wilson, Dcott D.

    2012-01-01

    The U.S. Department of Energy (DOE) and Lockheed Martin Space Systems Company (LMSSC) have been developing the Advanced Stirling Radioisotope Generator (ASRG) for use as a power system for space science missions. This generator would use two highefficiency Advanced Stirling Convertors (ASCs), developed by Sunpower, Inc., and NASA Glenn Research Center. The ASCs convert thermal energy from a radioisotope heat source into electricity. As part of ground testing of these ASCs, different operating conditions are used to simulate expected mission conditions. These conditions require achieving a particular operating frequency, hot-end and cold-end temperatures, and specified electrical power output for a given heat input. It is difficult to measure heat input to Stirling convertors due to the complex geometries of the hot components, temperature limits of sensor materials, and invasive integration of sensors. A thin-film heat flux sensor was used to directly measure heat input to an ASC. The effort succeeded in designing and fabricating unique sensors, which were integrated into a Stirling convertor ground test and exposed to test temperatures exceeding 700 C in air for 10,000 hr. Sensor measurements were used to calculate thermal efficiency for ASC-E (Engineering Unit) #1 and #4. The post-disassembly condition of the sensors is also discussed.

  19. Should electric fans be used during a heat wave?

    PubMed

    Jay, Ollie; Cramer, Matthew N; Ravanelli, Nicholas M; Hodder, Simon G

    2015-01-01

    Heat waves continue to claim lives, with the elderly and poor at greatest risk. A simple and cost-effective intervention is an electric fan, but public health agencies warn against their use despite no evidence refuting their efficacy in heat waves. A conceptual human heat balance model can be used to estimate the evaporative requirement for heat balance, the potential for evaporative heat loss from the skin, and the predicted sweat rate, with and without an electrical fan during heat wave conditions. Using criteria defined by the literature, it is clear that fans increase the predicted critical environmental limits for both the physiological compensation of endogenous/exogenous heat, and the onset of cardiovascular strain by an air temperature of ∼3-4 °C, irrespective of relative humidity (RH) for the young and elderly. Even above these critical limits, fans would apparently still provide marginal benefits at air temperatures as high as 51.1 °C at 10%RH for young adults and 48.1 °C at 10%RH for the elderly. Previous concerns that dehydration would be exacerbated with fan use do not seem likely, except under very hot (>40 °C) and dry (<10%RH) conditions, when predicted sweat losses are only greater with fans by a minor amount (∼20-30 mL/h). Relative to the peak outdoor environmental conditions reported during ten of the most severe heat waves in recent history, fan use would be advisable in all of these situations, even when reducing the predicted maximum sweat output for the elderly. The protective benefit of fans appears to be underestimated by current guidelines.

  20. Polymers Advance Heat Management Materials for Vehicles

    NASA Technical Reports Server (NTRS)

    2013-01-01

    For 6 years prior to the retirement of the Space Shuttle Program, the shuttles carried an onboard repair kit with a tool for emergency use: two tubes of NOAX, or "good goo," as some people called it. NOAX flew on all 22 flights following the Columbia accident, and was designed to repair damage that occurred on the exterior of the shuttle. Bill McMahon, a structural materials engineer at Marshall Space Flight Center says NASA needed a solution for the widest range of possible damage to the shuttle s exterior thermal protection system. "NASA looked at several options in early 2004 and decided on a sealant. Ultimately, NOAX performed the best and was selected," he says. To prove NOAX would work effectively required hundreds of samples manufactured at Marshall and Johnson, and a concerted effort from various NASA field centers. Johnson Space Center provided programmatic leadership, testing, tools, and crew training; Glenn Research Center provided materials analysis; Langley Research Center provided test support and led an effort to perform large patch repairs; Ames Research Center provided additional testing; and Marshall provided further testing and the site of NOAX manufacturing. Although the sealant never had to be used in an emergency situation, it was tested by astronauts on samples of reinforced carbon-carbon (RCC) during two shuttle missions. (RCC is the thermal material on areas of the shuttle that experience the most heat, such as the nose cone and wing leading edges.) The material handled well on orbit, and tests showed the NOAX patch held up well on RCC.

  1. Flexible heat pipes for CCD cooling on the Advanced Camera for Surveys

    NASA Astrophysics Data System (ADS)

    Schweickart, Russell B.; Buchko, Matthew M.

    1998-08-01

    The Advanced Camera for Surveys (ACS) is an instrument containing two charged-coupled device (CCD) cameras and a multi-anode multi-channel array (MAMA) detector being built by Ball Aerospace and Technologies Corporation for NASA's Goddard Space Flight Center. The instrument is scheduled to be installed in the Hubble Space Telescope during a space shuttle mission in December of 1999. The CCD detectors need to operate at a temperature below -80 degrees C in order to avoid unacceptable dark current. This cooling is achieved with thermo-electric coolers (TEC) mounted in evacuated assemblies that contain the detectors. Heat that is generated by the TECs must be dissipated to space. Since the CCd assemblies are centrally located within the instrument enclosure, a method must be provided for transferring this heat to a heat rejection surfaces. Heat pipes have been selected for this purpose since they are frequently used in space applications for passively transferring heat from sources to remotely located radiating panels. The alignment of the CCDs is critical, however, so the loads induced into the detectors and the optical bench containing the sensor assemblies through heat pipes must be minimized. Consequently, the CCD heat pipes have been designed with a flexible section to minimize either thermally generated or launch induced structural loads. Structural and thermal testing has shown that these heat pipes will allow the ACS detectors to attain their operating temperature while meeting alignment stability requirements. This paper presents the design of and test results from the ACS flexible heat pipes.

  2. Dynamic Response Testing in an Electrically Heated Reactor Test Facility

    NASA Technical Reports Server (NTRS)

    Bragg-Sitton, Shannon M.; Morton, T. J.

    2006-01-01

    Non-nuclear testing can be a valuable tool in development of a space nuclear power or propulsion system. In a non-nuclear test bed, electric heaters are used to simulate the heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system, but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and full nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response characteristics, and assess potential design improvements at a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE-100a heat pipe cooled, electrically heated reactor and heat exchanger hardware, utilizing a one-group solution to the point kinetics equations to simulate the expected neutronic response of the system (Bragg-Sitton, 2005). The current paper applies the same testing methodology to a direct drive gas cooled reactor system, demonstrating the applicability of the testing methodology to any reactor type and demonstrating the variation in system response characteristics in different reactor concepts. In each testing application, core power transients were controlled by a point kinetics model with reactivity feedback based on core average temperature; the neutron generation time and the temperature feedback coefficient are provided as model inputs. Although both system designs utilize a fast spectrum reactor, the method of cooling the reactor differs significantly, leading to a variable system response that can be demonstrated and assessed in a non-nuclear test facility.

  3. Advanced Soldier Thermoelectric Power System for Power Generation from Battlefield Heat Sources

    SciTech Connect

    Hendricks, Terry J.; Hogan, Tim; Case, Eldon D.; Cauchy, Charles J.

    2010-09-01

    The U.S. military uses large amounts of fuel during deployments and battlefield operations. This project sought to develop a lightweight, small form-factor, soldier-portable advanced thermoelectric (TE) system prototype to recover and convert waste heat from various deployed military equipment (i.e., diesel generators/engines, incinerators, vehicles, and potentially mobile kitchens), with the ultimate purpose of producing power for soldier battery charging, advanced capacitor charging, and other battlefield power applications. The technical approach employed microchannel technology, a unique “power panel” approach to heat exchange/TE system integration, and newly-characterized LAST (lead-antimony-silver-telluride) and LASTT (lead-antimony-silver-tin-telluride) TE materials segmented with bismuth telluride TE materials in designing a segmented-element TE power module and system. This project researched never-before-addressed system integration challenges (thermal expansion, thermal diffusion, electrical interconnection, thermal and electrical interfaces) of designing thin “power panels” consisting of alternating layers of thin, microchannel heat exchangers (hot and cold) sandwiching thin, segmented-element TE power generators. The TE properties, structurally properties, and thermal fatigue behavior of LAST and LASTT materials were developed and characterized such that the first segmented-element TE modules using LAST / LASTT materials were fabricated and tested at hot-side temperatures = 400 °C and cold-side temperatures = 40 °C. LAST / LASTT materials were successfully segmented with bismuth telluride and electrically interconnected with diffusion barrier materials and copper strapping within the module electrical circuit. A TE system design was developed to produce 1.5-1.6 kW of electrical energy using these new TE modules from the exhaust waste heat of 60-kW Tactical Quiet Generators as demonstration vehicles.

  4. Improvement of proton exchange membrane fuel cell overall efficiency by integrating heat-to-electricity conversion

    NASA Astrophysics Data System (ADS)

    Xie, Chungang; Wang, Shuxin; Zhang, Lianhong; Hu, S. Jack

    Proton exchange membrane fuel cells (PEMFCs) have shown to be well suited for distributed power generation due to their excellent performance. However, a PEMFC produces a considerable amount of heat in the process of electrochemical reaction. It is desirable to use thermal energy for electricity generation in addition to heating applications. Based on the operating characteristics of a PEMFC, an advanced thermal energy conversion system using "ocean thermal energy conversion" (OTEC) technology is applied to exploit the thermal energy of the PEMFC for electricity generation. Through this combination of technology, this unique PEMFC power plant not only achieves the combined heat and power efficiency, but also adequately utilizes heat to generate more valuable electricity. Exergy analysis illustrates the improvement of overall efficiency and energy flow distribution in the power plant. Analytical results show that the overall efficiency of the PEMFC is increased by 0.4-2.3% due to the thermal energy conversion (TEC) system. It is also evident that the PEMFC should operate within the optimal load range by balancing the design parameters of the PEMFC and of the TEC system.

  5. Electrical discharge heating of chondrules in the solar nebula

    NASA Technical Reports Server (NTRS)

    Love, Stanley G.; Keil, Klaus; Scott, Edward R. D.

    1995-01-01

    We present a rudimentary theoretical assessment of electrical discharge heating as a candidate mechanism for the formation of chondrules in the solar nebula. The discharge model combines estimates of the properties of the nebula, a mechanism for terrestrial thunderstorm electrification, and some fundamental electrical properties of gases. Large uncertainties in the model inputs limit these calculations to order-or-magnitude accuracy. Despite the uncertainty, it is possible to estimate an upper limit to the efficiency of nebular discharges at melting millimeter-sized stony objects. We find that electrical arcs analogous to terrestrial lightning could have occurred in the nebula, but that under most conditions these discharges probably could not have melted chondrules. Despite our difficulties, we believe the topic worthy of further investigation and suggest some experiments which could improve our understanding of nebular discharges.

  6. Advanced Materials Development Program: Ceramic Technology for Advanced Heat Engines program plan, 1983--1993

    SciTech Connect

    Not Available

    1990-07-01

    The purpose of the Ceramic Technology for Advanced Heat Engines (CTAHE) Project is the development of an industrial technology base capable of providing reliable and cost-effective high temperature ceramic components for application in advanced heat engines. There is a deliberate emphasis on industrial'' in the purpose statement. The project is intended to support the US ceramic and engine industries by providing the needed ceramic materials technology. The heat engine programs have goals of component development and proof-of-concept. The CTAHE Project is aimed at developing generic basic ceramic technology and does not involve specific engine designs and components. The materials research and development efforts in the CTAHE Project are focused on the needs and general requirements of the advanced gas turbine and low heat rejection diesel engines. The CTAHE Project supports the DOE Office of Transportation Systems' heat engine programs, Advanced Turbine Technology Applications (ATTAP) and Heavy Duty Transport (HDT) by providing the basic technology required for development of reliable and cost-effective ceramic components. The heat engine programs provide the iterative component design, fabrication, and test development logic. 103 refs., 18 figs., 11 tabs.

  7. Formation of the lunar crust - An electrical source of heating

    NASA Technical Reports Server (NTRS)

    Sonett, C. P.; Colburn, D. S.; Schwartz, K.

    1975-01-01

    A model for formation of the lunar crust based on heating by electrical induction is explored, while adherence is maintained to certain constraints associated with existing models of the solar system. The heating mechanism is based on eddy current induction from disordered magnetic fields swept outwards by an intense (T Tauri-like) plasma flow from the sun. The electrical theory is an alternative to intense short-period accretion as a source of heat for the evolution of lunar maria and highlands, provided that long-lived radioactives are not swept to the surface from too large a melt volume during the initial thermal episode. This formation of the lunar highlands does not intrinsically require rapid accretion, nor on this basis is the time of formation of the planets generally restricted to a very short time. The threshold temperature for eddy current heating is attained by either a solar nebula at 300-400 C during formation of the moon or a very low energy long-period accumulation of the moon, both leading to melting in ten to the fifth to ten to the seventh power years.

  8. Electrode wells for powerline-frequency electrical heating of soils

    DOEpatents

    Buettner, H.M.; Daily, W.D.; Aines, R.D.; Newmark, R.L.; Ramirez, A.L.; Siegel, W.H.

    1999-05-25

    An electrode well is described for use in powerline-frequency heating of soils for decontamination of the soil. Heating of soils enables the removal of volatile organic compounds from soil when utilized in combination with vacuum extraction. A preferred embodiment of the electrode well utilizes a mild steel pipe as the current-carrying conductor to at least one stainless steel electrode surrounded by a conductive backfill material, preferably graphite or steel shot. A covering is also provided for electrically insulating the current-carrying pipe. One of the electrode wells is utilized with an extraction well which is under subatmospheric pressure to withdraw the volatile material, such as gasoline and trichloroethylene (TCE) as it is heated. 4 figs.

  9. Electrode wells for powerline-frequency electrical heating of soils

    DOEpatents

    Buettner, Harley M.; Daily, William D.; Aines, Roger D.; Newmark, Robin L.; Ramirez, Abelardo L.; Siegel, William H.

    1999-01-01

    An electrode well for use in powerline-frequency heating of soils for decontamination of the soil. Heating of soils enables the removal of volatile organic compounds from soil when utilized in combination with vacuum extraction. A preferred embodiment of the electrode well utilizes a mild steel pipe as the current-carrying conductor to at least one stainless steel electrode surrounded by a conductive backfill material, preferably graphite or steel shot. A covering is also provided for electrically insulating the current-carrying pipe. One of the electrode wells is utilized with an extraction well which is under subatmospheric pressure to withdraw the volatile material, such as gasoline and trichioroethylene (TCE) as it is heated.

  10. Study of advanced electric propulsion system concept using a flywheel for electric vehicles

    NASA Technical Reports Server (NTRS)

    Younger, F. C.; Lackner, H.

    1979-01-01

    Advanced electric propulsion system concepts with flywheels for electric vehicles are evaluated and it is predicted that advanced systems can provide considerable performance improvement over existing electric propulsion systems with little or no cost penalty. Using components specifically designed for an integrated electric propulsion system avoids the compromises that frequently lead to a loss of efficiency and to inefficient utilization of space and weight. A propulsion system using a flywheel power energy storage device can provide excellent acceleration under adverse conditions of battery degradation due either to very low temperatures or high degrees of discharge. Both electrical and mechanical means of transfer of energy to and from the flywheel appear attractive; however, development work is required to establish the safe limits of speed and energy storage for advanced flywheel designs and to achieve the optimum efficiency of energy transfer. Brushless traction motor designs using either electronic commutation schemes or dc-to-ac inverters appear to provide a practical approach to a mass producible motor, with excellent efficiency and light weight. No comparisons were made with advanced system concepts which do not incorporate a flywheel.

  11. Energy intensity, electricity consumption, and advanced manufacturing-technology usage

    SciTech Connect

    Doms, M.E.; Dunne, T.

    1995-07-01

    This article reports on the relationship between the usage of advanced manufacturing technologies (AMTs) and energy consumption patterns in manufacturing plants. Using data from the Survey of Manufacturing Technology and the 1987 Census of Manufactures, we model the energy intensity and the electricity intensity of plants as functions of AMT usage and plant age. The main findings are that plants that utilize AMTs are less-energy intensive than plants not using AMTs, but consume proportionately more electricity as a fuel source. Additionally, older plants are generally more energy intensive and rely on fossil fuels to a greater extent than younger plants. 25 refs., 3 tabs.

  12. Hawaiian Electric Advanced Inverter Test Plan - Result Summary

    SciTech Connect

    Hoke, Anderson; Nelson, Austin; Prabakar, Kumaraguru; Nagarajan, Adarsh

    2016-10-14

    This presentation is intended to share the results of lab testing of five PV inverters with the Hawaiian Electric Companies and other stakeholders and interested parties. The tests included baseline testing of advanced inverter grid support functions, as well as distribution circuit-level tests to examine the impact of the PV inverters on simulated distribution feeders using power hardware-in-the-loop (PHIL) techniques. hardware-in-the-loop (PHIL) techniques.

  13. Heat to electricity conversion by cold carrier emissive energy harvesters

    SciTech Connect

    Strandberg, Rune

    2015-12-07

    This paper suggests a method to convert heat to electricity by the use of devices called cold carrier emissive energy harvesters (cold carrier EEHs). The working principle of such converters is explained and theoretical power densities and efficiencies are calculated for ideal devices. Cold carrier EEHs are based on the same device structure as hot carrier solar cells, but works in an opposite way. Whereas a hot carrier solar cell receives net radiation from the sun and converts some of this radiative heat flow into electricity, a cold carrier EEH sustains a net outflux of radiation to the surroundings while converting some of the energy supplied to it into electricity. It is shown that the most basic type of cold carrier EEHs have the same theoretical efficiency as the ideal emissive energy harvesters described earlier by Byrnes et al. In the present work, it is also shown that if the emission from the cold carrier EEH originates from electron transitions across an energy gap where a difference in the chemical potential of the electrons above and below the energy gap is sustained, power densities slightly higher than those given by Byrnes et al. can be achieved.

  14. Dynamic Response Testing in an Electrically Heated Reactor Test Facility

    NASA Astrophysics Data System (ADS)

    Bragg-Sitton, Shannon M.; Morton, T. J.

    2006-01-01

    Non-nuclear testing can be a valuable tool in the development of a space nuclear power or propulsion system. In a non-nuclear test bed, electric heaters are used to simulate the heat from nuclear fuel. Standard testing allows one to fully assess thermal, heat transfer, and stress related attributes of a given system, but fails to demonstrate the dynamic response that would be present in an integrated, fueled reactor system. The integration of thermal hydraulic hardware tests with simulated neutronic response provides a bridge between electrically heated testing and fueled nuclear testing. By implementing a neutronic response model to simulate the dynamic response that would be expected in a fueled reactor system, one can better understand system integration issues, characterize integrated system response times and response characteristics, and assess potential design improvements at a relatively small fiscal investment. Initial system dynamic response testing was demonstrated on the integrated SAFE-100a heat pipe (HP) cooled, electrically heated reactor and heat exchanger hardware, utilizing a one-group solution to the point kinetics equations to simulate the expected neutronic response of the system. Reactivity feedback calculations were then based on a bulk reactivity feedback coefficient and measured average core temperature. This paper presents preliminary results from similar dynamic testing of a direct drive gas cooled reactor system (DDG), demonstrating the applicability of the testing methodology to any reactor type and demonstrating the variation in system response characteristics in different reactor concepts. Although the HP and DDG designs both utilize a fast spectrum reactor, the method of cooling the reactor differs significantly, leading to a variable system response that can be demonstrated and assessed in a non-nuclear test facility. Planned system upgrades to allow implementation of higher fidelity dynamic testing are also discussed. Proposed DDG

  15. Applications of advanced electric/electronic technology to conventional aircraft

    NASA Technical Reports Server (NTRS)

    Heimbold, R. L.

    1980-01-01

    The desirability of seven advanced technologies as applied to three commercial aircraft of 1985 to 1995 was investigated. Digital fly by wire, multiplexing, ring laser gyro, integrated avionics, all electric airplane, electric load management, and fiber optics were considered for 500 passenger, 50 passenger, and 30 passenger aircraft. The major figure of merit used was Net Value of Technology based on procurement and operating cost over the life of the aircraft. An existing computer program, ASSET, was used to resize the aircraft and evalute fuel usage and maintenance costs for each candidate configuration. Conclusions were that, for the 500 passenger aircraft, all candidates had a worthwhile payoff with the all electric airplane having a large payoff.

  16. Development of advanced high-temperature heat flux sensors

    NASA Technical Reports Server (NTRS)

    Atkinson, W. H.; Strange, R. R.

    1982-01-01

    Various configurations of high temperature, heat flux sensors were studied to determine their suitability for use in experimental combustor liners of advanced aircraft gas turbine engines. It was determined that embedded thermocouple sensors, laminated sensors, and Gardon gauge sensors, were the most viable candidates. Sensors of all three types were fabricated, calibrated, and endurance tested. All three types of sensors met the fabricability survivability, and accuracy requirements established for their application.

  17. Forced Convection Boiling and Critical Heat Flux of Ethanol in Electrically Heated Tube Tests

    NASA Technical Reports Server (NTRS)

    Meyer, Michael L.; Linne, Diane L.; Rousar, Donald C.

    1998-01-01

    Electrically heated tube tests were conducted to characterize the critical heat flux (transition from nucleate to film boiling) of subcritical ethanol flowing at conditions relevant to the design of a regeneratively cooled rocket engine thrust chamber. The coolant was SDA-3C alcohol (95% ethyl alcohol, 5% isopropyl alcohol by weight), and tests were conducted over the following ranges of conditions: pressure from 144 to 703 psia, flow velocities from 9.7 to 77 ft/s, coolant subcooling from 33 to 362 F, and critical heat fluxes up to 8.7 BTU/in(exp 2)/sec. For the data taken near 200 psia, critical heat flux was correlated as a function of the product of velocity and fluid subcooling to within +/- 20%. For data taken at higher pressures, an additional pressure term is needed to correlate the critical heat flux. It was also shown that at the higher test pressures and/or flow rates, exceeding the critical heat flux did not result in wall burnout. This result may significantly increase the engine heat flux design envelope for higher pressure conditions.

  18. High temperature electrically conducting ceramic heating element and control system

    NASA Technical Reports Server (NTRS)

    Halbach, C. R.; Page, R. J.

    1975-01-01

    Improvements were made in both electrode technology and ceramic conductor quality to increase significantly the lifetime and thermal cycling capability of electrically conducting ceramic heater elements. These elements were operated in vacuum, inert and reducing environments as well as oxidizing atmospheres adding to the versatility of the conducting ceramic as an ohmic heater. Using stabilized zirconia conducting ceramic heater elements, a furnace was fabricated and demonstrated to have excellent thermal response and cycling capability. The furnace was used to melt platinum-20% rhodium alloy (melting point 1904 C) with an isothermal ceramic heating element having a nominal working cavity size of 2.5 cm diameter by 10.0 cm long. The furnace was operated to 1940 C with the isothermal ceramic heating element. The same furnace structure was fitted with a pair of main heater elements to provide axial gradient temperature control over a working cavity length of 17.8 cm.

  19. Optimization of the electrically heated catalyst for emission purification efficiency

    SciTech Connect

    Jeong, L.; Jang, J.; Yeo, G.; Kim, Y.

    1996-09-01

    It is well known that the EHC (Electrically Heated Catalyst) is very effective for the reduction of cold-start hydrocarbon emissions. To optimize EHC applications for LEV (Low Emission Vehicle) and ULEV (Ultra Low Emission Vehicle) standards, the effects of heating and secondary air injection on the emission purification efficiency in FTP (Federal Test Procedure) were evaluated with three different EHC system configurations. The exhaust manifold location EHC system in which the EHC with a light-off catalyst is installed near the exhaust manifold, yields 0.038g/mile of THC (Total Hydrocarbon emissions) when the test was performed according to the FTP with an engine-aged condition equivalent to 50,000 miles. Therefore, the ULEV standards could be achieved through the system. A new battery system for the EHC and a single battery system for vehicle application were evaluated. Evaluation of the Ni-MH battery for EHC system is included.

  20. Outdoor unit construction for an electric heat pump

    DOEpatents

    Draper, R.; Lackey, R.S.

    1984-09-11

    The outdoor unit for an electric heat pump is provided with an upper portion containing propeller fan means for drawing air through the lower portion containing refrigerant coil means in the form of four discrete coils connected together in a subassembly forming a W shape, the unit being provided with four adjustable legs which are retracted in shipment, and are adjusted on site to elevate the unit to a particular height suitable for the particular location in which the unit is installed. 4 figs.

  1. Electrically heated particulate filter regeneration using hydrocarbon adsorbents

    DOEpatents

    Gonze, Eugene V [Pinckney, MI

    2011-02-01

    An exhaust system that processes exhaust generated by an engine is provided. The system generally includes a particulate filter (PF) that filters particulates from the exhaust wherein an upstream end of the PF receives exhaust from the engine. A grid of electrically resistive material selectively heats exhaust passing through the upstream end to initiate combustion of particulates within the PF. A hydrocarbon adsorbent coating applied to the PF releases hydrocarbons into the exhaust to increase a temperature of the combustion of the particulates within the PF.

  2. Outdoor unit construction for an electric heat pump

    DOEpatents

    Draper, Robert; Lackey, Robert S.

    1984-01-01

    The outdoor unit for an electric heat pump is provided with an upper portion 10 containing propeller fan means 14 for drawing air through the lower portion 12 containing refrigerant coil means 16 in the form of four discrete coils connected together in a subassembly forming a W shape, the unit being provided with four adjustable legs 64 which are retracted in shipment, and are adjusted on site to elevate the unit to a particular height suitable for the particular location in which the unit is installed.

  3. Power and heat fluctuation theorems for electric circuits.

    PubMed

    van Zon, R; Ciliberto, S; Cohen, E G D

    2004-04-02

    Using recent fluctuation theorems from nonequilibrium statistical mechanics, we extend the theory for voltage fluctuations in electric circuits to power and heat fluctuations. They could be of particular relevance for the functioning of small circuits. This is done for a parallel resistor and capacitor with a constant current source for which we use the analogy with a Brownian particle dragged through a fluid by a moving harmonic potential, where circuit-specific analogs are needed on top of the Brownian-Nyquist analogy. The results may also hold for other circuits as another example shows.

  4. Advanced Electric Propulsion for Space Solar Power Satellites

    NASA Technical Reports Server (NTRS)

    Oleson, Steve

    1999-01-01

    The sun tower concept of collecting solar energy in space and beaming it down for commercial use will require very affordable in-space as well as earth-to-orbit transportation. Advanced electric propulsion using a 200 kW power and propulsion system added to the sun tower nodes can provide a factor of two reduction in the required number of launch vehicles when compared to in-space cryogenic chemical systems. In addition, the total time required to launch and deliver the complete sun tower system is of the same order of magnitude using high power electric propulsion or cryogenic chemical propulsion: around one year. Advanced electric propulsion can also be used to minimize the stationkeeping propulsion system mass for this unique space platform. 50 to 100 kW class Hall, ion, magnetoplasmadynamic, and pulsed inductive thrusters are compared. High power Hall thruster technology provides the best mix of launches saved and shortest ground to Geosynchronous Earth Orbital Environment (GEO) delivery time of all the systems, including chemical. More detailed studies comparing launch vehicle costs, transfer operations costs, and propulsion system costs and complexities must be made to down-select a technology. The concept of adding electric propulsion to the sun tower nodes was compared to a concept using re-useable electric propulsion tugs for Low Earth Orbital Environment (LEO) to GEO transfer. While the tug concept would reduce the total number of required propulsion systems, more launchers and notably longer LEO to GEO and complete sun tower ground to GEO times would be required. The tugs would also need more complex, longer life propulsion systems and the ability to dock with sun tower nodes.

  5. Advanced Electrical Materials and Components Development: An Update

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.

    2005-01-01

    The primary means to develop advanced electrical components is to develop new and improved materials for magnetic components (transformers, inductors, etc.), capacitors, and semiconductor switches and diodes. This paper will give an update of the Advanced Power Electronics and Components Technology being developed by the NASA Glenn Research Center for use in future Power Management and Distribution subsystems used in space power systems for spacecraft and lunar and planetary surface power. The initial description and status of this technology program was presented two years ago at the First International Energy Conversion Engineering Conference held at Portsmouth, Virginia, August 2003. The present paper will give a brief background of the previous work reported and a summary of research performed the past several years on soft magnetic materials characterization, dielectric materials and capacitor developments, high quality silicon carbide atomically smooth substrates, and SiC static and dynamic device characterization under elevated temperature conditions. The rationale for and the benefits of developing advanced electrical materials and components for the PMAD subsystem and also for the total power system will also be briefly discussed.

  6. Modelling of thermoacoustic phenomena in an electrically heated Rijke tube

    NASA Astrophysics Data System (ADS)

    Beke, Tamas

    2010-11-01

    Thermoacoustic instability plays an important role in various technical applications, for instance in jet or rocket motors, thermoacoustic engines, pulse combustors and industrial burners. The main objective of this paper is to present the theory of thermoacoustic oscillations, and for this purpose a Rijke-type thermal device was built. The Rijke tube is a simple device open at both ends with a mean airflow and a concentrated heat source (a heated wire grid). It serves as a convenient prototypical example to understand thermoacoustic effects since it is a simplified thermoacoustic resonator; once excited, under certain conditions, it is capable of creating a sustained sound when thermal energy is added. In this paper we present a project that includes physical measuring, examination and modelling. We have employed electrically heated Rijke tubes in our thermoacoustic school project work, and present a numerical algorithm to predict the transition to instability; in this model the effects of the main system parameters are demonstrated. The aim of our project is to help our students enhance their knowledge about thermoacoustics and develop their applied information technology skills.

  7. Recent advances in liquid mixtures in electric fields

    NASA Astrophysics Data System (ADS)

    Katsir, Yael; Tsori, Yoav

    2017-02-01

    When immiscible liquids are subject to electric fields interfacial forces arise due to a difference in the permittivity or the conductance of the liquids, and these forces lead to shape change in droplets or to interfacial instabilities. In this topical review we discuss recent advances in the theory and experiments of liquids in electric fields with an emphasis on liquids which are initially miscible and demix under the influence of an external field. In purely dielectric liquids demixing occurs if the electrode geometry leads to sufficiently large field gradients. In polar liquids field gradients are prevalent due to screening by dissociated ions irrespective of the electrode geometry. We examine the conditions for these ‘electro prewetting’ transitions and highlight few possible systems where they might be important, such as in stabilization of colloids and in gating of pores in membranes.

  8. Performance evaluation of advanced battery technologies for electric vehicle applications

    NASA Astrophysics Data System (ADS)

    Deluca, W. H.; Tummillo, A. F.; Kulaga, J. E.; Webster, C. E.; Gillie, K. R.; Hogrefe, R. L.

    1990-01-01

    At the Argonne Analysis and Diagnostic Laboratory, advanced battery technology evaluations are performed under simulated electric vehicle operating conditions. During 1989 and the first quarter of 1990, single cell and multicell modules from seven developers were examined for the Department of Energy and Electric Power Research Institute. The results provide battery users, developers, and program managers with an interim measure of the progress being made in battery R&D programs, a comparison of battery technologies, and a source of basic data for modeling and continuing R&D. This paper summarizes the performance and life characterizations of two single cells and seven 3- to 960-cell modules that encompass six technologies (Na/S, Ni/Fe, Ni/Cd, Ni-metal hydride, lead-acid, and Zn/Br).

  9. Hybrid and electric advanced vehicle systems (heavy) simulation

    NASA Technical Reports Server (NTRS)

    Hammond, R. A.; Mcgehee, R. K.

    1981-01-01

    A computer program to simulate hybrid and electric advanced vehicle systems (HEAVY) is described. It is intended for use early in the design process: concept evaluation, alternative comparison, preliminary design, control and management strategy development, component sizing, and sensitivity studies. It allows the designer to quickly, conveniently, and economically predict the performance of a proposed drive train. The user defines the system to be simulated using a library of predefined component models that may be connected to represent a wide variety of propulsion systems. The development of three models are discussed as examples.

  10. Comparative analysis of compact heat exchangers for application as the intermediate heat exchanger for advanced nuclear reactors

    SciTech Connect

    Bartel, N.; Chen, M.; Utgikar, V. P.; Sun, X.; Kim, I. -H.; Christensen, R.; Sabharwall, P.

    2015-04-04

    A comparative evaluation of alternative compact heat exchanger designs for use as the intermediate heat exchanger in advanced nuclear reactor systems is presented in this article. Candidate heat exchangers investigated included the Printed circuit heat exchanger (PCHE) and offset strip-fin heat exchanger (OSFHE). Both these heat exchangers offer high surface area to volume ratio (a measure of compactness [m2/m3]), high thermal effectiveness, and overall low pressure drop. Helium–helium heat exchanger designs for different heat exchanger types were developed for a 600 MW thermal advanced nuclear reactor. The wavy channel PCHE with a 15° pitch angle was found to offer optimum combination of heat transfer coefficient, compactness and pressure drop as compared to other alternatives. The principles of the comparative analysis presented here will be useful for heat exchanger evaluations in other applications as well.

  11. Comparative analysis of compact heat exchangers for application as the intermediate heat exchanger for advanced nuclear reactors

    DOE PAGES

    Bartel, N.; Chen, M.; Utgikar, V. P.; ...

    2015-04-04

    A comparative evaluation of alternative compact heat exchanger designs for use as the intermediate heat exchanger in advanced nuclear reactor systems is presented in this article. Candidate heat exchangers investigated included the Printed circuit heat exchanger (PCHE) and offset strip-fin heat exchanger (OSFHE). Both these heat exchangers offer high surface area to volume ratio (a measure of compactness [m2/m3]), high thermal effectiveness, and overall low pressure drop. Helium–helium heat exchanger designs for different heat exchanger types were developed for a 600 MW thermal advanced nuclear reactor. The wavy channel PCHE with a 15° pitch angle was found to offer optimummore » combination of heat transfer coefficient, compactness and pressure drop as compared to other alternatives. The principles of the comparative analysis presented here will be useful for heat exchanger evaluations in other applications as well.« less

  12. Taming the heat flux problem: Advanced divertors towards fusion power

    SciTech Connect

    Kotschenreuther, M.; Mahajan, S.; Valanju, P. M.; Covele, B.; Waelbroeck, F. L.; Canik, John M.; LaBombard, Brian

    2015-09-11

    The next generation fusion machines are likely to face enormous heat exhaust problems. In addition to summarizing major issues and physical processes connected with these problems, we discuss how advanced divertors, obtained by modifying the local geometry, may yield workable solutions. We also point out that: (1) the initial interpretation of recent experiments show that the advantages, predicted, for instance, for the X-divertor (in particular, being able to run a detached operation at high pedestal pressure) correlate very well with observations, and (2) the X-D geometry could be implemented on ITER (and DEMOS) respecting all the relevant constraints. As a result, a roadmap for future research efforts is proposed.

  13. Magnetic field characteristics of electric bed-heating devices

    SciTech Connect

    Wilson, B.W.; Davis, K.C.; Heimbigner, T.; Buschbom, R.L.; Lee, G.M.; Yost, M.G.

    1996-12-01

    Measurements of the flux density and spectra of magnetic fields (MFs) generated by several types of electric bed heaters (EBH) were made in order to characterize the MFs to which the fetus may be exposed in utero from the mother`s use of these devices. Data on MFs were gathered from more than 1,300 in-home and laboratory spot measurements. In-home measurements taken at seven different positions 10 cm from the EBHs determined that the mean flux density at the estimated position of the fetus relative to the device was 0.45 {micro}T (4.5 mG) for electric blankets and 0.20 {micro}T (2.0 mG) for electrically heated water beds. A rate-of-change (RC) metric applied to the nighttime segment of 24 h EMDEX-C personal-dosimeter measurements, which were taken next to the bed of volunteers, yielded an approximate fourfold to sixfold higher value for electric blanket users compared to water-bed heater users. These same data records yielded an approximate twofold difference for the same measurements when evaluated by the time-weighted-average (TWA) MF exposure metric. Performance of exposure meters was checked against standard fields generated in the laboratory, and studies of sources of variance in the in-home measurement protocols were carried out. Spectral measurements showed that the EBHs measured produced no appreciable high-frequency MFs. Data gathered during this work will be used in interpreting results from a component of the California Pregnancy Outcome Study, which evaluates the use of EBHs as a possible risk factor in miscarriage.

  14. Heat rate improvement at Sunflower Electric`s Holcomb Station - a programmatic approach

    SciTech Connect

    Linville, C.; Nelson, K.E.; DesJardins, R.R.

    1996-05-01

    This paper describes the heat rate improvement program implemented at Sunflower Electric Power Corporations Holcomb Generating Station located in Holcomb, Kansas. The Holcomb Station is a large coal-fired generating plant that supplies electricity to Southwestern. Kansas and surrounding states. In 1993, Sunflower Electric (SEPC) established a continuing heat rate improvement program at the Holcomb Station which consisted of a periodic performance test program in combination with continuous on-line monitoring. This paper provides an overview of the test program and initial results and describes a unique approach to monitoring boiler feed pump performance especially suitable for on-line monitoring. implementation of a 15-user LAN-based on-line performance monitoring system is also described. In addition to technical issues, the paper addresses some of the {open_quotes}human factors{close_quotes} encountered while promoting acceptance and use of the on-line monitoring system by all levels of plant personnel. The importance of proper program planning and long term management support is stressed.

  15. Simulation of Rocket-Grade Kerosene Flowing in an Electrically Heated Experimental Apparatus

    DTIC Science & Technology

    2015-07-01

    fluid, heat and electricity in an experimental apparatus designed to test fuel thermal stability. A numerical simulation is performed for the purposes...dimensional combined flow of fluid, heat and electricity in an experimental apparatus designed to test fuel thermal stability. A numerical simulation is...Service  Excellence Simulation of Rocket-Grade Kerosene Flowing in an Electrically Heated Apparatus Propulsion and Energy Forum 27-29 July 2015

  16. Modeling heat generation and flow in the Advanced Neutron Source Corrosion Test Loop specimen

    SciTech Connect

    Pawel, R.E.; Yarbrough, D.W.

    1988-01-01

    A finite difference computer code HEATING5 was used to model heat generation and flow in a typical experiment envisioned for the Advanced Neutron Source Corrosion Test Loop. The electrical resistivity and thermal conductivity of the test specimen were allowed to vary with local temperature, and the corrosion layer thickness was assigned along the length of the specimen in the manner predicted by the Griess Correlation. The computer solved the two-dimensional transport problem for a given total power dissipated in the specimen and stipulated coolant temperatures and water-side heat-transfer coefficients. The computed specimen temperatures were compared with those calculated on the basis of approximate analytical equations involving the total power dissipation and the assignment of the physical properties based on temperatures at single axial points on the specimen. The comparisons indicate that when temperature variations are large along the axis of the specimen, the variation in local heat flux should not be overlooked when using approximate equations or models. The approximate equations are most accurate near the center of the specimen where the heat flux remains closest to the average value, and in that region the calculated quantities agree closely with the results of the computer code. 4 figs., 1 tab.

  17. Kuiper Belt Object Orbiter Using Advanced Radioisotope Power Sources and Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; McGuire, Melissa L.; Dankanich, John; Colozza, Anthony; Schmitz, Paul; Khan, Omair; Drexler, Jon; Fittje, James

    2011-01-01

    A joint NASA GRC/JPL design study was performed for the NASA Radioisotope Power Systems Office to explore the use of radioisotope electric propulsion for flagship class missions. The Kuiper Belt Object Orbiter is a flagship class mission concept projected for launch in the 2030 timeframe. Due to the large size of a flagship class science mission larger radioisotope power system building blocks were conceptualized to provide the roughly 4 kW of power needed by the NEXT ion propulsion system and the spacecraft. Using REP the spacecraft is able to rendezvous with and orbit a Kuiper Belt object in 16 years using either eleven (no spare) 420 W advanced RTGs or nine (with a spare) 550 W advanced Stirling Radioisotope systems. The design study evaluated integrating either system and estimated impacts on cost as well as required General Purpose Heat Source requirements.

  18. QUANTUM WELL THERMOELECTRICS FOR CONVERTING WASTE HEAT TO ELECTRICITY

    SciTech Connect

    Saeid Ghamaty; Sal Marchetti

    2005-03-03

    New thermoelectric materials using Quantum Well (QW) technology are expected to increase the energy conversion efficiency to more than 25% from the present 5%, which will allow for the low cost conversion of waste heat into electricity. Hi-Z Technology, Inc. has been developing QW technology over the past six years. It will use Caterpillar, Inc., a leader in the manufacture of large scale industrial equipment, for verification and life testing of the QW films and modules. Other members of the team are Pacific Northwest National Laboratory, who will sputter large area QW films. The Scope of Work is to develop QW materials from their present proof-of-principle technology status to a pre-production level over a proposed three year period. This work will entail fabricating the QW films through a sputtering process of 50 {micro}m thick multi layered films and depositing them on 12 inch diameter, 5 {micro}m thick Si substrates. The goal in this project is to produce a basic 10-20 watt module that can be used to build up any size generator such as: a 5-10 kW Auxiliary Power Unit (APU), a multi kW Waste Heat Recovery Generator (WHRG) for a class 8 truck or as small as a 10-20 watt unit that would fit on a daily used wood fired stove and allow some of the estimated 2-3 billion people on earth, who have no electricity, to recharge batteries (such as a cell phone) or directly power radios, TVs, computers and other low powered devices.

  19. Results of advanced battery technology evaluations for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Gillie, K.R.; Kulaga, J.E.; Smaga, J.A.; Tummillo, A.F.; Webster, C.E.

    1992-09-01

    Advanced battery technology evaluations are performed under simulated electric-vehicle operating conditions at the Analysis & Diagnostic Laboratory (ADL) of Argonne National Laboratory. The ADL results provide insight Into those factors that limit battery performance and life. The ADL facilities include a test laboratory to conduct battery experimental evaluations under simulated application conditions and a post-test analysis laboratory to determine, In a protected atmosphere if needed, component compositional changes and failure mechanisms. This paper summarizes the performance characterizations and life evaluations conducted during 1991--1992 on both single cells and multi-cell modules that encompass eight battery technologies [Na/S, Li/MS (M=metal), Ni/MH, Ni/Cd, Ni/Zn, Ni/Fe, Zn/Br, and Pb-acid]. These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division, and the Electric Power Research Institute. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The results help identify the most-promising R&D approaches for overcoming battery limitations, and provide battery users, developers, and program managers with a measure of the progress being made in battery R&D programs, a comparison of battery technologies, and basic data for modeling.

  20. Recovery Act - Sustainable Transportation: Advanced Electric Drive Vehicle Education Program

    SciTech Connect

    Caille, Gary

    2013-12-13

    The collective goals of this effort include: 1) reach all facets of this society with education regarding electric vehicles (EV) and plug–in hybrid electric vehicles (PHEV), 2) prepare a workforce to service these advanced vehicles, 3) create web–based learning at an unparalleled level, 4) educate secondary school students to prepare for their future and 5) train the next generation of professional engineers regarding electric vehicles. The Team provided an integrated approach combining secondary schools, community colleges, four–year colleges and community outreach to provide a consistent message (Figure 1). Colorado State University Ventures (CSUV), as the prime contractor, plays a key program management and co–ordination role. CSUV is an affiliate of Colorado State University (CSU) and is a separate 501(c)(3) company. The Team consists of CSUV acting as the prime contractor subcontracted to Arapahoe Community College (ACC), CSU, Motion Reality Inc. (MRI), Georgia Institute of Technology (Georgia Tech) and Ricardo. Collaborators are Douglas County Educational Foundation/School District and Gooru (www.goorulearning.org), a nonprofit web–based learning resource and Google spin–off.

  1. Results of advanced battery technology evaluations for electric vehicle applications

    NASA Astrophysics Data System (ADS)

    Deluca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F.; Webster, C. E.

    1992-10-01

    Advanced battery technology evaluations are performed under simulated electric-vehicle operating conditions at the Analysis and Diagnostic Laboratory (ADL) of Argonne National Laboratory. The ADL results provide insight into those factors that limit battery performance and life. The ADL facilities include a test laboratory to conduct battery experimental evaluations under simulated application conditions and a post-test analysis laboratory to determine, in a protected atmosphere if needed, component compositional changes and failure mechanisms. This paper summarizes the performance characterizations and life evaluations conducted during 1991-1992 on both single cells and multi-cell modules that encompass eight battery technologies (Na/S, Li/MS (M=metal), Ni/MH, Ni/Cd, Ni/Zn, Ni/Fe, Zn/Br, and Pb-acid). These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division, and the Electric Power Research Institute. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The results help identify the most-promising R&D approaches for overcoming battery limitations, and provide battery users, developers, and program managers with a measure of the progress being made in battery R&D programs, a comparison of battery technologies, and basic data for modeling.

  2. Results of advanced batter technology evaluations for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Gillie, K.R.; Kulaga, J.E.; Smaga, J.A.; Tummillo, A.F.; Webster, C.E.

    1992-01-01

    Advanced battery technology evaluations are performed under simulated electric-vehicle operating conditions at the Analysis Diagnostic Laboratory (ADL) of Argonne National Laboratory. The ADL results provide insight Into those factors that limit battery performance and life. The ADL facilities include a test laboratory to conduct battery experimental evaluations under simulated application conditions and a post-test analysis laboratory to determine, In a protected atmosphere if needed, component compositional changes and failure mechanisms. This paper summarizes the performance characterizations and life evaluations conducted during 1991--1992 on both single cells and multi-cell modules that encompass eight battery technologies (Na/S, Li/MS (M=metal), Ni/MH, Ni/Cd, Ni/Zn, Ni/Fe, Zn/Br, and Pb-acid). These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division, and the Electric Power Research Institute. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The results help identify the most-promising R D approaches for overcoming battery limitations, and provide battery users, developers, and program managers with a measure of the progress being made in battery R D programs, a comparison of battery technologies, and basic data for modeling.

  3. Independent Manipulation of Heat and Electrical Current via Bifunctional Metamaterials

    NASA Astrophysics Data System (ADS)

    Moccia, Massimo; Castaldi, Giuseppe; Savo, Salvatore; Sato, Yuki; Galdi, Vincenzo

    2014-04-01

    Spatial tailoring of the material constitutive properties is a well-known strategy to mold the local flow of given observables in different physical domains. Coordinate-transformation-based methods (e.g., transformation optics) offer a powerful and systematic approach to design anisotropic, spatially inhomogeneous artificial materials (metamaterials) capable of precisely manipulating wave-based (electromagnetic, acoustic, elastic) as well as diffusion-based (heat) phenomena in a desired fashion. However, as versatile as these approaches have been, most designs have thus far been limited to serving single-target functionalities in a given physical domain. Here, we present a step towards a "transformation multiphysics" framework that allows independent and simultaneous manipulation of multiple physical phenomena. As a proof of principle of this new scheme, we design and synthesize (in terms of realistic material constituents) a metamaterial shell that simultaneously behaves as a thermal concentrator and an electrical "invisibility cloak." Our numerical results open up intriguing possibilities in the largely unexplored phase space of multifunctional metadevices, with a wide variety of potential applications to electrical, magnetic, acoustic, and thermal scenarios.

  4. New heat treatment process for advanced high-strength steels

    NASA Astrophysics Data System (ADS)

    Bublíková, D.; Jeníček, Š.; Vorel, I.; Mašek, B.

    2017-02-01

    Today’s advanced steels are required to possess high strength and ductility. It can be achieved by choosing an appropriate steel chemistry which has a substantial effect on the properties obtained by heat treatment. Mechanical properties influenced the presence of retained austenite in the final structure. Steels of this group typically require complicated heat treatment which places great demands on the equipment used. The present paper introduces new procedures aimed at simplifying the heat treatment of high-strength steels with the use of material-technological modelling. Four experimental steels were made and cast, whose main alloying additions were manganese, silicon, chromium, molybdenum and nickel. The steels were treated using the Q-P process with subsequent interrupted quenching. The resulting structure was a mixture of martensite and retained austenite. Strength levels of more than 2000 MPa combined with 10-15 % elongation were obtained. These properties thus offer potential for the manufacture of intricate closed-die forgings with a reduced weight. Intercritical annealing was obtained structure not only on the basis of martensite, but also with certain proportion of bainitic ferrite and retained austenite.

  5. Dynamic conversion of solar generated heat to electricity

    NASA Technical Reports Server (NTRS)

    Powell, J. C.; Fourakis, E.; Hammer, J. M.; Smith, G. A.; Grosskreutz, J. C.; Mcbride, E.

    1974-01-01

    The effort undertaken during this program led to the selection of the water-superheated steam (850 psig/900 F) crescent central receiver as the preferred concept from among 11 candidate systems across the technological spectrum of the dynamic conversion of solar generated heat to electricity. The solar power plant designs were investigated in the range of plant capacities from 100 to 1000 Mw(e). The investigations considered the impacts of plant size, collector design, feed-water temperature ratio, heat rejection equipment, ground cover, and location on solar power technical and economic feasibility. For the distributed receiver systems, the optimization studies showed that plant capacities less than 100 Mw(e) may be best. Although the size of central receiver concepts was not parametrically investigated, all indications are that the optimal plant capacity for central receiver systems will be in the range from 50 to 200 Mw(e). Solar thermal power plant site selection criteria and methodology were also established and used to evaluate potentially suitable sites. The result of this effort was to identify a site south of Inyokern, California, as typically suitable for a solar thermal power plant. The criteria used in the selection process included insolation and climatological characteristics, topography, and seismic history as well as water availability.

  6. Recycling readiness of advanced batteries for electric vehicles

    SciTech Connect

    Jungst, R.G.

    1997-09-01

    Maximizing the reclamation/recycle of electric-vehicle (EV) batteries is considered to be essential for the successful commercialization of this technology. Since the early 1990s, the US Department of Energy has sponsored the ad hoc advanced battery readiness working group to review this and other possible barriers to the widespread use of EVs, such as battery shipping and in-vehicle safety. Regulation is currently the main force for growth in EV numbers and projections for the states that have zero-emission vehicle (ZEV) programs indicate about 200,000 of these vehicles would be offered to the public in 2003 to meet those requirements. The ad hoc Advanced Battery Readiness Working Group has identified a matrix of battery technologies that could see use in EVs and has been tracking the state of readiness of recycling processes for each of them. Lead-acid, nickel/metal hydride, and lithium-ion are the three EV battery technologies proposed by the major automotive manufacturers affected by ZEV requirements. Recycling approaches for the two advanced battery systems on this list are partly defined, but could be modified to recover more value from end-of-life batteries. The processes being used or planned to treat these batteries are reviewed, as well as those being considered for other longer-term technologies in the battery recycling readiness matrix. Development efforts needed to prepare for recycling the batteries from a much larger EV population than exists today are identified.

  7. Study of a heat rejection system for the Nuclear Electric Propulsion (NEP) spacecraft

    NASA Technical Reports Server (NTRS)

    Ernest, D. M.

    1982-01-01

    Two different heat pipe radiator elements, one intended for use with the power conversion subsystem of the NASA funded nuclear electric propulsion (NEP) spacecraft, and one intended for use with the DOE funded space power advanced reactor (SPAR) system were tested and evaluated. The NEP stainless steel/sodium heat pipe was 4.42 meters long and had a 1 cm diameter. Thermal performance testing at 920 K showed a non-limited power level of 3560 watts, well in excess of the design power of 2600 watts. This test verified the applicability of screen arteries for use in long radiator heat pipes. The SPAR titanium/potassium heat pipe was 5.5 meters long and had a semicircular crossection with a 4 cm diameter. Thermal performance testing at 775 K showed a maximum power level of 1.86 kW, somewhat short of the desired 2.6 kW beginning of life design requirement. The reduced performance was shown to be the result of the inability of the evaporator wall wick (shot blasted evaporator wall) to handle the required liquid flow.

  8. QUANTUM WELL THERMOELECTRICS FOR CONVERTING WASTE HEAT TO ELECTRICITY

    SciTech Connect

    Saeid Ghamaty

    2006-03-31

    New thermoelectric materials using Quantum Well (QW) technology are expected to increase the energy conversion efficiency to more than 25% from the present 5%, which will allow for the low cost conversion of waste heat into electricity. Hi-Z Technology, Inc. has been developing QW technology over the past six years. It will use Caterpillar, Inc., a leader in the manufacture of large scale industrial equipment, for verification and life testing of the QW films and modules. Other members of the team are Pacific Northwest National Laboratory, who will sputter large area QW films. The Scope of Work is to develop QW materials from their present proof-of-principle technology status to a pre-production level over a proposed three year period. This work will entail fabricating the QW films through a sputtering process of 50 {micro}m thick multi layered films and depositing them on 12 inch diameter, 5 {micro}m thick Si substrates. The goal in this project is to produce the technology for fabricating a basic 10-20 watt module that can be used to build up any size generator such as: a 5-10 kW Auxiliary Power Unit (APU), a multi kW Waste Heat Recovery Generator (WHRG) for a class 8 truck or as small as a 10-20 watt unit that would fit on a daily used wood fired stove and allow some of the estimated 2-3 billion people on earth, who have no electricity, to recharge batteries (such as a cell phone) or directly power radios, TVs, computers and other low powered devices. In this quarter Hi-Z has continued fabrication of the QW films and also continued development of joining techniques for fabricating the N and P legs into a couple. The upper operating temperature limit for these films is unknown and will be determined via the isothermal aging studies that are in progress. We are reporting on these studies in this report. The properties of the QW films that are being evaluated are Seebeck, thermal conductivity and thermal-to-electricity conversion efficiency.

  9. QUANTUM WELL THERMOELECTRICS FOR CONVERTING WASTE HEAT TO ELECTRICITY

    SciTech Connect

    Saeid Ghamaty

    2006-02-01

    New thermoelectric materials using Quantum Well (QW) technology are expected to increase the energy conversion efficiency to more than 25% from the present 5%, which will allow for the low cost conversion of waste heat into electricity. Hi-Z Technology, Inc. has been developing QW technology over the past six years. It will use Caterpillar, Inc., a leader in the manufacture of large scale industrial equipment, for verification and life testing of the QW films and modules. Other members of the team are Pacific Northwest National Laboratory, who will sputter large area QW films. The Scope of Work is to develop QW materials from their present proof-of-principle technology status to a pre-production level over a proposed three year period. This work will entail fabricating the QW films through a sputtering process of 50 {micro}m thick multi layered films and depositing them on 12 inch diameter, 5 {micro}m thick Si substrates. The goal in this project is to produce the technology for fabricating a basic 10-20 watt module that can be used to build up any size generator such as: a 5-10 kW Auxiliary Power Unit (APU), a multi kW Waste Heat Recovery Generator (WHRG) for a class 8 truck or as small as a 10-20 watt unit that would fit on a daily used wood fired stove and allow some of the estimated 2-3 billion people on earth, who have no electricity, to recharge batteries (such as a cell phone) or directly power radios, TVs, computers and other low powered devices. In this quarter Hi-Z has continued fabrication of the QW films and also continued development of joining techniques for fabricating the N and P legs into a couple. The upper operating temperature limit for these films is unknown and will be determined via the isothermal aging studies that are in progress. We are reporting on these studies in this report. The properties of the QW films that are being evaluated are Seebeck, thermal conductivity and thermal-to-electricity conversion efficiency.

  10. Advanced coal technologies in Czech heat and power systems

    SciTech Connect

    Noskievic, P.; Ochodek, T.

    1998-04-01

    Coal is the only domestic source of fossil fuel in the Czech Republic. The coal reserves are substantial and their share in total energy use is about 60%. Presently necessary steps in making coal utilisation more friendly towards the environment have been taken and fairly well established, and an interest to develop and build advanced coal units has been observed. One IGCC system has been put into operation, and circa 10 AFBC units are in operation or under construction. Preparatory steps have been taken in building an advanced combustion unit fuelled by pulverised coal and retrofit action is taking place in many heating plants. An actual experience has shown two basic problems: (1) Different characteristic of domestic lignite, especially high content of ash, cause problems applying well-tried foreign technologies and apparently a more focused attention shall have to be paid to the quality of coal combusted. (2) Low prices of lignite (regarding energy, lignite is four times cheaper then coal) do not oblige to increase efficiency of the standing equipment applying advanced technologies. It will be of high interest to observe the effect of the effort of the European Union to establish a kind of carbon tax. It could dramatically change the existing scene in clean coal power generation by the logical pressure to increase the efficiency of energy transformation. In like manner the gradual liberalisation of energy prices might have similar consequences and it is a warranted expectation that, up to now not the best, energy balance will improve in near future.

  11. Development and Evaluation of Active Thermal Management System for Lithium-Ion Batteries using Solid-State Thermoelectric Heat Pump and Heat Pipes with Electric Vehicular Applications

    NASA Astrophysics Data System (ADS)

    Parekh, Bhaumik Kamlesh

    Lithium-Ion batteries have become a popular choice for use in energy storage systems in electric vehicles (EV) and Hybrid electric vehicles (HEV) because of high power and high energy density. But the use of EV and HEV in all climates demands for a battery thermal management system (BTMS) since temperature effects their performance, cycle life and, safety. Hence the BTMS plays a crucial role in the performance of EV and HEV. In this paper, three thermal management systems are studied: (a) simple aluminum as heat spreader material, (b) heat pipes as heat spreader, and (c) advanced combined solid state thermoelectric heat pump (TE) and heat pipe system; these will be subsequently referred to as Design A, B and C, respectively. A detailed description of the designs and the experimental setup is presented. The experimental procedure is divided into two broad categories: Cooling mode and Warming-up mode. Cooling mode covers the conditions when a BTMS is responsible to cool the battery pack through heat dissipation and Warming-up mode covers the conditions when the BTMS is responsible to warm the battery pack in a low temperature ambient condition, maintaining a safe operating temperature of the battery pack in both modes. The experimental procedure analyzes the thermal management system by evaluating the effect of each variable like heat sink area, battery heat generation rate, cooling air temperature, air flow rate and TE power on parameters like maximum temperature of the battery pack (T max), maximum temperature difference (DeltaT) and, heat transfer through heat sink/cooling power of TE (Q c). The results show that Design C outperforms Design A and Design B in spite of design issues which reduce its efficiency, but can still be improved to achieve better performance.

  12. Priestley's Shadow and Lavoisier's Influence: Electricity and Heat in the Late Eighteenth and Early Nineteenth Centuries

    NASA Astrophysics Data System (ADS)

    Fisher, Amy

    In the late eighteenth century, Joseph Priestley argued that any complete theory of heat also had to explain electrical phenomena, which manifested many similar effects to heat. For example, sparking or heating a sample of trapped air caused a reduction in the volume of air and made the gas toxic to living organisms. Because of the complexity of electrical and thermal phenomena, Antoine Lavoisier did not address electrical action in his published works. Rather, he focused on those effects produced by heating alone. With the success of Lavoisier's caloric theory of heat, natural philosophers and chemists continued to debate the relationship between heat and electricity. In this presentation, I compare and contrast the fate of caloric in early-nineteenth-century electrical studies via the work of two scientists: Humphry Davy in Britain and Robert Hare in America.

  13. Field evaluation of advanced controls for the retrofit of packaged air conditioners and heat pumps

    SciTech Connect

    Wang, Weimin; Katipamula, Srinivas; Ngo, Hung; Underhill, Ronald M.; Taasevigen, Danny J.; Lutes, Robert G.

    2015-09-01

    This paper documents the magnitude of energy savings achievable in the field by retrofitting existing packaged rooftop units (RTUs) with advanced control strategies not ordinarily used for RTUs. A total of 66 RTUs on 8 different buildings were retrofitted with a commercially available advanced controller for improving RTU operational efficiency. The controller features enhanced air-side economizer control, multi-speed fan control, and demand controlled ventilation. Of the 66 RTUs, 18 are packaged heat pumps and the rest are packaged air conditioners with gas heat. The eight buildings cover four building types and four climate conditions. Based on the data collected for about a whole year, the advanced controller reduced the normalized annual RTU energy consumption between 22% and 90%, with an average of 57% for all RTUs. The average fractional savings uncertainty was 12% at 95% confidence level. Normalized annual electricity savings were in the range between 0.47 kWh/h (kWh per hour of RTU operation) and 7.21 kWh/h, with an average of 2.39 kWh/h. RTUs greater than 53 kW and runtime greater than 14 hours per day had payback periods less than 3 years even at $0.05/kWh.

  14. Evaluation of Advanced Stirling Convertor Net Heat Input Correlation Methods Using a Thermal Standard

    NASA Technical Reports Server (NTRS)

    Briggs, Maxwell; Schifer, Nicholas

    2011-01-01

    Test hardware used to validate net heat prediction models. Problem: Net Heat Input cannot be measured directly during operation. Net heat input is a key parameter needed in prediction of efficiency for convertor performance. Efficiency = Electrical Power Output (Measured) divided by Net Heat Input (Calculated). Efficiency is used to compare convertor designs and trade technology advantages for mission planning.

  15. Advancements in Afterbody Radiative Heating Simulations for Earth Entry

    NASA Technical Reports Server (NTRS)

    Johnston, Christopher O.; Panesi, Marco; Brandis, Aaron M.

    2016-01-01

    Four advancements to the simulation of backshell radiative heating for Earth entry are presented. The first of these is the development of a flow field model that treats electronic levels of the dominant backshell radiator, N, as individual species. This is shown to allow improvements in the modeling of electron-ion recombination and two-temperature modeling, which are shown to increase backshell radiative heating by 10 to 40%. By computing the electronic state populations of N within the flow field solver, instead of through the quasi-steady state approximation in the radiation code, the coupling of radiative transition rates to the species continuity equations for the levels of N, including the impact of non-local absorption, becomes feasible. Implementation of this additional level of coupling between the flow field and radiation codes represents the second advancement presented in this work, which is shown to increase the backshell radiation by another 10 to 50%. The impact of radiative transition rates due to non-local absorption indicates the importance of accurate radiation transport in the relatively complex flow geometry of the backshell. This motivates the third advancement, which is the development of a ray-tracing radiation transport approach to compute the radiative transition rates and divergence of the radiative flux at every point for coupling to the flow field, therefore allowing the accuracy of the commonly applied tangent-slab approximation to be assessed for radiative source terms. For the sphere considered at lunar-return conditions, the tangent-slab approximation is shown to provide a sufficient level of accuracy for the radiative source terms, even for backshell cases. This is in contrast to the agreement between the two approaches for computing the radiative flux to the surface, which differ by up to 40%. The final advancement presented is the development of a nonequilibrium model for NO radiation, which provides significant backshell

  16. ADVANCED ELECTRIC AND MAGNETIC MATERIAL MODELS FOR FDTD ELECTROMAGNETIC CODES

    SciTech Connect

    Poole, B R; Nelson, S D; Langdon, S

    2005-05-05

    The modeling of dielectric and magnetic materials in the time domain is required for pulse power applications, pulsed induction accelerators, and advanced transmission lines. For example, most induction accelerator modules require the use of magnetic materials to provide adequate Volt-sec during the acceleration pulse. These models require hysteresis and saturation to simulate the saturation wavefront in a multipulse environment. In high voltage transmission line applications such as shock or soliton lines the dielectric is operating in a highly nonlinear regime, which require nonlinear models. Simple 1-D models are developed for fast parameterization of transmission line structures. In the case of nonlinear dielectrics, a simple analytic model describing the permittivity in terms of electric field is used in a 3-D finite difference time domain code (FDTD). In the case of magnetic materials, both rate independent and rate dependent Hodgdon magnetic material models have been implemented into 3-D FDTD codes and 1-D codes.

  17. Outer Planet Exploration with Advanced Radioisotope Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Oleson, Steven; Gefert, Leon; Patterson, Michael; Schreiber, Jeffrey; Benson, Scott; McAdams, Jim; Ostdiek, Paul

    2002-01-01

    In response to a request by the NASA Deep Space Exploration Technology Program, NASA Glenn Research Center conducted a study to identify advanced technology options to perform a Pluto/Kuiper mission without depending on a 2004 Jupiter Gravity Assist, but still arriving before 2020. A concept using a direct trajectory with small, sub-kilowatt ion thrusters and Stirling radioisotope power systems was shown to allow the same or smaller launch vehicle class as the chemical 2004 baseline and allow a launch slip and still flyby in the 2014 to 2020 timeframe. With this promising result the study was expanded to use a radioisotope power source for small electrically propelled orbiter spacecraft for outer planet targets such as Uranus, Neptune, and Pluto.

  18. High-voltage electrical survey advances using UV/IR

    NASA Astrophysics Data System (ADS)

    Ninedorf, Daniel A.; Stolper, Roel; Hart, Jaco

    2008-03-01

    Technology miniaturization has made new advancements in high voltage electrical surveying possible. A solar-blind ultraviolet image overlaid onto infrared, combined with a solar-blind ultraviolet image and then overlaid onto color visible in the same camera with a weight of 6 pounds provides the comparison images and portability to allow an operator to do on-the-spot analysis and repair priority assignment. The UV-VIS image provides the quickest location and identification. The UV-IR image allows analysis to determine if there is damage and the severity. This can be accomplished in just seconds thru menu selection: before it required two separate cameras. This presentation will provide examples of different images and analysis, with operating time from hand-held, laboratory, vehicle and aerial camera mounts.

  19. Advanced Electric Submersible Pump Design Tool for Geothermal Applications

    SciTech Connect

    Xuele Qi; Norman Turnquist; Farshad Ghasripoor

    2012-05-31

    Electrical Submersible Pumps (ESPs) present higher efficiency, larger production rate, and can be operated in deeper wells than the other geothermal artificial lifting systems. Enhanced Geothermal Systems (EGS) applications recommend lifting 300 C geothermal water at 80kg/s flow rate in a maximum 10-5/8-inch diameter wellbore to improve the cost-effectiveness. In this paper, an advanced ESP design tool comprising a 1D theoretical model and a 3D CFD analysis has been developed to design ESPs for geothermal applications. Design of Experiments was also performed to optimize the geometry and performance. The designed mixed-flow type centrifugal impeller and diffuser exhibit high efficiency and head rise under simulated EGS conditions. The design tool has been validated by comparing the prediction to experimental data of an existing ESP product.

  20. Survey of advanced-heat-pump developments for space conditioning

    SciTech Connect

    Fairchild, P.D.

    1981-01-01

    A survey of heat pump projects with special emphasis on those supported by DOE, EPRI, and the Gas Research Institute is presented. Some historical notes on heat pump development are discussed. Market and equipment trends, well water and ground-coupled heat pumps, heat-actuated heat pump development, and international interest in heat pumps are also discussed. 30 references.

  1. High temperature electrical energy storage: advances, challenges, and frontiers.

    PubMed

    Lin, Xinrong; Salari, Maryam; Arava, Leela Mohana Reddy; Ajayan, Pulickel M; Grinstaff, Mark W

    2016-10-24

    With the ongoing global effort to reduce greenhouse gas emission and dependence on oil, electrical energy storage (EES) devices such as Li-ion batteries and supercapacitors have become ubiquitous. Today, EES devices are entering the broader energy use arena and playing key roles in energy storage, transfer, and delivery within, for example, electric vehicles, large-scale grid storage, and sensors located in harsh environmental conditions, where performance at temperatures greater than 25 °C are required. The safety and high temperature durability are as critical or more so than other essential characteristics (e.g., capacity, energy and power density) for safe power output and long lifespan. Consequently, significant efforts are underway to design, fabricate, and evaluate EES devices along with characterization of device performance limitations such as thermal runaway and aging. Energy storage under extreme conditions is limited by the material properties of electrolytes, electrodes, and their synergetic interactions, and thus significant opportunities exist for chemical advancements and technological improvements. In this review, we present a comprehensive analysis of different applications associated with high temperature use (40-200 °C), recent advances in the development of reformulated or novel materials (including ionic liquids, solid polymer electrolytes, ceramics, and Si, LiFePO4, and LiMn2O4 electrodes) with high thermal stability, and their demonstrative use in EES devices. Finally, we present a critical overview of the limitations of current high temperature systems and evaluate the future outlook of high temperature batteries with well-controlled safety, high energy/power density, and operation over a wide temperature range.

  2. Visualization Of Water Vaporization During Electrical Heating Process With X-ray Tomography

    NASA Astrophysics Data System (ADS)

    Wang, Jie; Li, Yubin; Erath, Michael; Kantzas, Apostolos

    2007-06-01

    This paper deals with the study of electrical heating as a potential method for recovery of heavy oil and bitumen from unconsolidated sand formations of Northern Alberta. Electrical heating is a preferred energy transfer method for heating relatively shallow formations containing bitumen with limited support for high-pressure steam injection. Simulation results demonstrated that although electrical heating can contribute to the recovery of oil, substantially more oil would be recovered if the formation or injected water were allowed to boil. Thus the in-situ steam creation has been the target of simulation and experimental work presented here.

  3. Multiwalled carbon nanotube/polydimethylsiloxane composite films as high performance flexible electric heating elements

    SciTech Connect

    Yan, Jing; Jeong, Young Gyu

    2014-08-04

    High performance elastomeric electric heating elements were prepared by incorporating various contents of pristine multiwalled carbon nanotube (MWCNT) in polydimethylsiloxane (PDMS) matrix by using an efficient solution-casting and curing technique. The pristine MWCNTs were identified to be uniformly dispersed in the PDMS matrix and the electrical percolation of MWCNTs was evaluated to be at ∼0.27 wt. %, where the electrical resistivity of the MWCNT/PDMS composite films dropped remarkably. Accordingly, the composite films with higher MWCNT contents above 0.3 wt. % exhibit excellent electric heating performance in terms of temperature response rapidity and electric energy efficiency at constant applied voltages. In addition, the composite films, which were thermally stable up to 250 °C, showed excellent heating-cooling cyclic performance, which was associated with operational stability in actual electric heating applications.

  4. Seebeck effect influence on joule heat evolution in electrically conductive silicate materials

    NASA Astrophysics Data System (ADS)

    Fiala, Lukáš; Medved, Igor; Maděra, Jiří; Černý, Robert

    2016-07-01

    In general, silicate building materials are non-conductive matters that are not able to evolve heat when they are subjected to an external voltage. However, the electrical conductivity can be increased by addition of electrically conductive admixtures in appropriate amount which leads to generation of conductive paths in materials matrix. Such enhanced materials can evolve Joule heat and are utilizable as a core of self-heating or snow-melting systems. In this paper, Joule heat evolution together with Seebeck effect in electrically conductive silicate materials was taken into consideration and the model based on heat equation with included influence of DC electric field was proposed. Besides, a modeling example of heating element was carried out on FEM basis and time development of temperature in chosen surface points was expressed in order to declare ability of such system to be applicable.

  5. Primary electric power generation systems for advanced-technology engines

    NASA Technical Reports Server (NTRS)

    Cronin, M. J.

    1983-01-01

    The advantages of the all electric airplane are discussed. In the all electric airplane the generator is the sole source of electric power; it powers the primary and secondary flight controls, the environmentals, and the landing gear. Five candidates for all electric power systems are discussed and compared. Cost benefits of the all electric airplane are discussed.

  6. Advanced coal technologies in Czech heat and power systems

    SciTech Connect

    Noskievic, P. Ochodek, T.

    1998-07-01

    Coal is the only domestic source of fossil fuel in the Czech Republic. The coal reserves are substantial and their share in total energy use is about 60%. Presently, necessary steps in making coal utilization more friendly towards the environment have been taken and fairly well established, and an interest to develop and build advanced coal units has been observed. One IGCC system has been put into operation, and circa 10 AFBC units are in operation or under construction. preparatory steps have been taken in building an advanced combustion unit fueled by pulverized coal and retrofit action is taking place in many heating plants. An actual experience has shown two basic problems: (1) Different characteristic of domestic lignite, especially high content of ash, cause problems applying well-tried foreign technologies and apparently a more focused attention shall have to be paid to the quality of coal combusted. (2) Low prices of lignite (regarding energy, lignite is four times cheaper than coal) do not result in an increased efficiency of the standing equipment by applying advanced technologies. It will be of high interest to observe the effect of the effort of the European Union to establish a kind of carbon tax. It could dramatically change the existing scene in clean coal power generation by the logical pressure to increase the efficiency of energy transformation. In like manner the gradual liberalization of energy prices might have similar consequences and it is a warranted expectation that, up to now not the best, energy balance will improve in the near future.

  7. Monitoring six-phase ohmic heating of contaminated soils using electrical resistance tomography

    SciTech Connect

    Ramirez, A.L.; Daily, W.D.

    1994-09-01

    Electrical resistance tomography (ERT) was used to monitor six-phase ohmic heating used for the insitu remediation of volatile organic compounds from subsurface water and soil at the Savannah River Site, near Aiken, South Carolina. The changes in electrical conductivity caused by six-phase ohmic-heating in a clay layer located in the vadose zone were monitored during a period of approximately 2 months, before, during and after heating. From an array of electrodes located in 4 boreholes, we collected electrical resistivity data between five pairs of adjacent holes pairs. This data was used to calculate tomographs which showed the electrical conductivity changes along five vertical planes. The difference tomographs show the combined effects of moisture redistribution and heating caused by six-phase heating and vapor extraction. The tomographs show that most of the clay layer increased in electrical conductivity during the first 3 weeks of the 4 week long heating phase. At this time, the electrical conductivities near the center of the heating array were twice as large as the pre-heat conductivities. Then the electrical conductivity started to decrease for portions of the clay layer closest to the vapor extraction well. We propose that the conductivity decreases are due to the removal of moisture by the heating and vacuum extraction. Parts of the clay layer near the extraction well reached electrical conductivities as low as 40% of the pre-heating values. We propose that these regions of lower than ambient electrical conductivities are indicators of regions where the vapor removal by vacuum extraction was most effective. At the end of the heating phase, our estimates suggest that the clay saturation may have dropped to as low as 10% based on the observed conductivity changes.

  8. Radiative heat transfer in many-body systems: Coupled electric and magnetic dipole approach

    NASA Astrophysics Data System (ADS)

    Dong, Jian; Zhao, Junming; Liu, Linhua

    2017-03-01

    The many-body radiative heat transfer theory [P. Ben-Abdallah, S.-A. Biehs, and K. Joulain, Phys. Rev. Lett. 107, 114301 (2011), 10.1103/PhysRevLett.107.114301] considered only the contribution from the electric dipole moment. For metal particles, however, the magnetic dipole moment due to eddy current plays an important role, which can further couple with the electric dipole moment to introduce crossed terms. In this paper, we develop the coupled electric and magnetic dipole (CEMD) approach for the radiative heat transfer in a collection of objects in mutual interaction. Due to the coupled electric and magnetic interactions, four terms, namely the electric-electric, the electric-magnetic, the magnetic-electric, and the magnetic-magnetic terms, contribute to the radiative heat flux and the local energy density. The CEMD is applied to study the radiative heat transfer between various dimers of nanoparticles. It is found that each of the four terms can dominate the radiative heat transfer depending on the position and composition of particles. Moreover, near-field many-body interactions are studied by CEMD considering both dielectric and metallic nanoparticles. The near-field radiative heat flux and local energy density can be greatly increased when the particles are in coupled resonances. Surface plasmon polariton and surface phonon polariton can be coupled to enhance the radiative heat flux.

  9. Electricity-producing heating apparatus utilizing a turbine generator in a semi-closed brayton cycle

    DOEpatents

    Labinov, Solomon D.; Christian, Jeffrey E.

    2003-10-07

    The present invention provides apparatus and methods for producing both heat and electrical energy by burning fuels in a stove or boiler using a novel arrangement of a surface heat exchanger and microturbine-powered generator and novel surface heat exchanger. The equipment is particularly suited for use in rural and relatively undeveloped areas, especially in cold regions and highlands.

  10. An assessment of ocean thermal energy conversion as an advanced electric generation methodology

    NASA Astrophysics Data System (ADS)

    Heydt, Gerald T.

    1993-03-01

    Ocean thermal energy conversion (OTEC) is a process that employs the temperature difference between surface and deep ocean water to alternately evaporate and condense a working fluid. In the open-cycle OTEC configuration, the working fluid is seawater. In the closed-cycle configuration, a working fluid such as propane is used. In this paper, OTEC is assessed for its practical merits for electric power generation, and the history of the process is reviewed. Because the OTEC principle operates under a small net temperature difference regime, rather large amounts of seawater and working fluid are required. The energy requirements for pumping these fluids may be greater than the energy recovered from the OTEC engine itself. The concept of net power production is discussed. The components of a typical OTEC plant are discussed with emphasis on the evaporator heat exchanger. Operation of an OTEC electric generating station is discussed, including transient operation. Perhaps the most encouraging aspect of OTEC is the recent experiments and efforts at the Natural Energy Laboratory in Hawaii, which are discussed in the paper. Remarks are made on bottlenecks and the future of OTEC as an advanced electric generation methodology.

  11. An assessment of ocean thermal energy conversion as an advanced electric generation methodology

    SciTech Connect

    Heydt, G.T. . School of Electrical Engineering)

    1993-03-01

    Ocean thermal energy conversion (OTEC) is a process that employs the temperature difference between surface and deep ocean water to alternately evaporate and condense a working fluid. In the open-cycle OTEC configuration, the working fluid is seawater. In the closed-cycle configuration, a working fluid such as propane is used. In this paper, OTEC is assessed for its practical merits for electric power generation. The process is not new--and its history is reviewed. Because the OTEC principle operates under a small net temperature difference regime, rather large amounts of seawater and working fluid are required. The energy requirements for pumping these fluids may be greater than the energy recovered from the OTEC engine itself. The concept of net power production is discussed. The components of a typical OTEC plant are discussed with emphasis on the evaporator heat exchanger. Operation of an OTEC electric generating station is discussed, including transient operation. Perhaps the most encouraging aspect of OTEC is the recent experiments and efforts at the Natural Energy Laboratory--Hawaii (NELH). The NELH work is summarized in the paper. Remarks are made on bottlenecks and the future of OTEC as an advanced electric generation methodology.

  12. Advanced multistage turbine blade aerodynamics, performance, cooling, and heat transfer

    SciTech Connect

    Fleeter, S.; Lawless, P.B.

    1995-10-01

    The gas turbine has the potential for power production at the highest possible efficiency. The challenge is to ensure that gas turbines operate at the optimum efficiency so as to use the least fuel and produce minimum emissions. A key component to meeting this challenge is the turbine. Turbine performance, both aerodynamics and heat transfer, is one of the barrier advanced gas turbine development technologies. This is a result of the complex, highly three-dimensional and unsteady flow phenomena in the turbine. Improved turbine aerodynamic performance has been achieved with three-dimensional highly-loaded airfoil designs, accomplished utilizing Euler or Navier-Stokes Computational Fluid Dynamics (CFD) codes. These design codes consider steady flow through isolated blade rows. Thus they do not account for unsteady flow effects. However, unsteady flow effects have a significant impact on performance. Also, CFD codes predict the complete flow field. The experimental verification of these codes has traditionally been accomplished with point data - not corresponding plane field measurements. Thus, although advanced CFD predictions of the highly complex and three-dimensional turbine flow fields are available, corresponding data are not. To improve the design capability for high temperature turbines, a detailed understanding of the highly unsteady and three-dimensional flow through multi-stage turbines is necessary. Thus, unique data are required which quantify the unsteady three-dimensional flow through multi-stage turbine blade rows, including the effect of the film coolant flow. This requires experiments in appropriate research facilities in which complete flow field data, not only point measurements, are obtained and analyzed. Also, as design CFD codes do not account for unsteady flow effects, the next logical challenge and the current thrust in CFD code development is multiple-stage analyses that account for the interactions between neighboring blade rows.

  13. Advanced Multi-Effect Distillation System for Desalination Using Waste Heat fromGas Brayton Cycles

    SciTech Connect

    Haihua Zhao; Per F. Peterson

    2012-10-01

    Generation IV high temperature reactor systems use closed gas Brayton Cycles to realize high thermal efficiency in the range of 40% to 60%. The waste heat is removed through coolers by water at substantially greater average temperature than in conventional Rankine steam cycles. This paper introduces an innovative Advanced Multi-Effect Distillation (AMED) design that can enable the production of substantial quantities of low-cost desalinated water using waste heat from closed gas Brayton cycles. A reference AMED design configuration, optimization models, and simplified economics analysis are presented. By using an AMED distillation system the waste heat from closed gas Brayton cycles can be fully utilized to desalinate brackish water and seawater without affecting the cycle thermal efficiency. Analysis shows that cogeneration of electricity and desalinated water can increase net revenues for several Brayton cycles while generating large quantities of potable water. The AMED combining with closed gas Brayton cycles could significantly improve the sustainability and economics of Generation IV high temperature reactors.

  14. District heating from electric-generating plants and municipal incinerators: local planner's assessment guide

    SciTech Connect

    Pferdehirt, W.; Kron, N. Jr.

    1980-11-01

    This guide is designed to aid local government planners in the preliminary evaluation of the feasibility of district heating using heat recovered from electric generating plants and municipal incinerators. System feasibility is indicated by: (1) the existence of an adequate supply of nearby waste heat, (2) the presence of a sufficiently dense and large thermal load, and (3) a favorable cost comparison with conventional heating methods. 34 references.

  15. Influence of the Thomson effect on the pulse heating of high-current electrical contacts

    NASA Astrophysics Data System (ADS)

    Merkushev, A. G.; Pavleino, M. A.; Pavleino, O. M.; Pavlov, V. A.

    2014-09-01

    Pulse heating of high-current contacts is notable for the presence of considerable temperature gradients in the contact area, which cause the Thomson effect—the appearance of thermoelectric currents. The amount of this effect against conventional Joule heat release is quantitatively estimated. Pulse heating of electrical contacts is numerically simulated with the use of the Comsol program package. It is demonstrated that thermoelectric currents make a negligible contribution to heating in the case of copper contacts.

  16. Advanced Electrical, Optical and Data Communication Infrastructure Development

    SciTech Connect

    Simon Cobb

    2011-04-30

    The implementation of electrical and IT infrastructure systems at the North Carolina Center for Automotive Research , Inc. (NCCAR) has achieved several key objectives in terms of system functionality, operational safety and potential for ongoing research and development. Key conclusions include: (1) The proven ability to operate a high speed wireless data network over a large 155 acre area; (2) Node to node wireless transfers from access points are possible at speeds of more than 50 mph while maintaining high volume bandwidth; (3) Triangulation of electronic devices/users is possible in areas with overlapping multiple access points, outdoor areas with reduced overlap of access point coverage considerably reduces triangulation accuracy; (4) Wireless networks can be adversely affected by tree foliage, pine needles are a particular challenge due to the needle length relative to the transmission frequency/wavelength; and (5) Future research will use the project video surveillance and wireless systems to further develop automated image tracking functionality for the benefit of advanced vehicle safety monitoring and autonomous vehicle control through 'vehicle-to-vehicle' and 'vehicle-to-infrastructure' communications. A specific advantage realized from this IT implementation at NCCAR is that NC State University is implementing a similar wireless network across Centennial Campus, Raleigh, NC in 2011 and has benefited from lessons learned during this project. Consequently, students, researchers and members of the public will be able to benefit from a large scale IT implementation with features and improvements derived from this NCCAR project.

  17. Possible role of external radial electric field on ion heating in an FRC

    NASA Astrophysics Data System (ADS)

    Gupta, Deepak; Trask, E.; Korepanov, S.; Granstedt, E.; Osin, D.; Roche, T.; Deng, B.; Beall, M.; Zhai, K.; TAE Team

    2016-10-01

    In C-2/C-2U FRCs, a radial electric field is applied by either plasma guns or biased electrodes inside the divertors, at both ends of the machine. The electric field plays an important role in stabilizing the FRC; thus, providing a favorable target condition to a neutral beam injection. In addition, it is also observed that the application of radial electric field may lead to a heating of ions. Radial profile of impurity ion emission, azimuthal velocity and temperature are measured under different configurations. The conditions and evidences of ion heating due to the electric field biasing will be presented and discussed. Radial momentum balance equation of oxygen impurity ions is used with these measurements to estimate the radial electric field profile. Parameters affecting the ion heating due to biasing will also be discussed with some correlations. The external radial electric field is planned to be applied by biased electrodes and plasma guns in C-2W inner/outer divertors.

  18. Advanced thermoplastic materials for district heating piping systems

    SciTech Connect

    Raske, D.T.; Karvelas, D.E.

    1988-04-01

    The work described in this report represents research conducted in the first year of a three-year program to assess, characterize, and design thermoplastic piping for use in elevated-temperature district heating (DH) systems. The present report describes the results of a program to assess the potential usefulness of advanced thermoplastics as piping materials for use in DH systems. This includes the review of design rules for thermoplastic materials used as pipes, a survey of candidate materials and available mechanical properties data, and mechanical properties testing to obtain baseline data on a candidate thermoplastic material extruded as pipe. The candidate material studied in this phase of the research was a polyetherimide resin, Ultem 1000, which has a UL continuous service temperature rating of 338/degree/F (170/degree/C). The results of experiments to determine the mechanical properties between 68 and 350/degree/F (20 and 177/degree/C) were used to establish preliminary design values for this material. Because these prototypic pipes were extruded under less than optimal conditions, the mechanical properties obtained are inferior to those expected from typical production pipes. Nevertheless, the present material in the form of 2-in. SDR 11 pipe (2.375-in. O. D. by 0.216-in. wall) would have a saturated water design pressure rating of /approximately/34 psig at 280/degree/F. 16 refs., 6 figs., 8 tabs.

  19. Experimental Investigation of Pool Boiling Heat Transfer Enhancement in Microgravity in the Presence of Electric Fields

    NASA Technical Reports Server (NTRS)

    Herman, C.

    2000-01-01

    The research carried out in the Heat Transfer Laboratory of the Johns Hopkins University was motivated by previous studies indicating that in terrestrial applications nucleate boiling heat transfer can be increased by a factor of 50 when compared to values obtained for the same system without electric fields. Imposing an external electric field holds the promise to improve pool boiling heat transfer in low gravity, since a phase separation force other than gravity is introduced. The influence of electric fields on bubble formation has been investigated both experimentally and theoretically.

  20. Short and long term energy source technologies for electrically-heated catalysts

    SciTech Connect

    Bass, E.A.; Johnston, R.; Hunt, B.; Rodriguez, G.; Gottberg, I.; Ishizuka, A.; Hall, W.

    1996-12-31

    A consortium of six companies formed by Southwest Research Institute conducted an investigation into alternative electric power supplies for electrically heated catalysts (EHCs). Previous studies showed that, due to their high power and energy requirements upon engine start, battery-powered EHCs would cause premature failure of common lead-acid batteries. This project identified and characterized several alternative electric energy sources. Production starting, lighting, and ignition (SLI) batteries were evaluated along with lead-acid electric vehicle batteries, nickel-cadmium aircraft batteries, prototype ultracapacitors, and a modified alternator. Battery Council International and US Advanced Battery Consortium test methods were employed where applicable. Evaluations included ambient and low-temperature ({minus}18 C) constant-current discharge characterization, low-temperature peak-power determination, self-discharge, and passenger car Federal Test Procedure (FTP) emissions and fuel economy. As demonstrated by discharge-energy and peak-power tests, some EV batteries may have potential for the EHC/SLI application. Other appeared to be poorly suited due to low-temperature problems. The best low-temperature performance was observed with ultracapacitors. These units were also the least to be affected by the power versus energy trade-off. The problems with these prototype storage units were high cost and self-discharge rate. Alternator power for EHCs as an alternative to energy storage devices was successfully demonstrated on a vehicle. Power produced was a linear function of engine speed and EHC load. High-voltage switching devices will be necessary for successful use of alternator power on EHCs. A fuel economy penalty was expected, but not observed during the FTP vehicle demonstration.

  1. Multiple pulse-heating experiments with different current to determine total emissivity, heat capacity, and electrical resistivity of electrically conductive materials at high temperatures.

    PubMed

    Watanabe, Hiromichi; Yamashita, Yuichiro

    2012-01-01

    A modified pulse-heating method is proposed to improve the accuracy of measurement of the hemispherical total emissivity, specific heat capacity, and electrical resistivity of electrically conductive materials at high temperatures. The proposed method is based on the analysis of a series of rapid resistive self-heating experiments on a sample heated at different temperature rates. The method is used to measure the three properties of the IG-110 grade of isotropic graphite at temperatures from 850 to 1800 K. The problem of the extrinsic heating-rate effect, which reduces the accuracy of the measurements, is successfully mitigated by compensating for the generally neglected experimental error associated with the electrical measurands (current and voltage). The results obtained by the proposed method can be validated by the linearity of measured quantities used in the property determinations. The results are in reasonably good agreement with previously published data, which demonstrate the suitability of the proposed method, in particular, to the resistivity and total emissivity measurements. An interesting result is the existence of a minimum in the emissivity of the isotropic graphite at around 1120 K, consistent with the electrical resistivity results.

  2. Influence of low- and high-frequency electrical heating on biodegrading microorganisms in soil: soil respiration.

    PubMed

    Roland, Ulf; Holzer, Frank; Kopinke, Frank-Dieter

    2013-01-01

    The influence of electrical heating on microbiological processes in soil has been studied to evaluate the potential for enhancing biodegradation of pollutants by controlling the temperature. A frequency of 50 Hz (power line frequency) was applied for resistive heating. Dielectric heating was realized using a frequency of 13.56 MHz (radio frequency). Both techniques were compared with conventional heating in a water bath. For experiments in laboratory and full scale, a model soil and a contaminated original soil were used. It was shown that under conditions capable for heating soil to 35 degrees C or even 60 degrees C, soil respiration as a measure for microbial activity was not hindered by electrical heating when temperature and moisture content were comparable with conventional heating. The variations of soil respiration were reversible upon temperature changes. Under certain conditions, periodical fluctuations of microbiological activity were observed. Several possible explanations including chronobiology are discussed without being able to provide an unambiguous interpretation for this effect.

  3. Process Heat Exchanger Options for the Advanced High Temperature Reactor

    SciTech Connect

    Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson

    2011-06-01

    The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.

  4. Modeling of heat evolution in silicate building materials with electrically conductive admixtures

    NASA Astrophysics Data System (ADS)

    Fiala, Lukáš; Maděra, Jiří; Vejmelková, Eva; Černý, Robert

    2016-12-01

    Silicate building materials are electrically non-conductive, in general. However, a sufficient amount of electrically conductive admixtures can significantly increase their electrical conductivity. Consequently, new practical applications of such materials are available. Materials with enhanced electrical properties can be used as self-sensing sensors monitoring evolution of cracks, electromagnetic shields or cores of deicing systems. This paper deals with the modeling of heat evolution in silicate building materials by the action of passing electric current. Due to the conducting paths formed in the material's matrix by adding a sufficient amount of electrically conductive admixture and applying electric voltage on the installed electrodes, electric current is passing through the material. Thanks to the electric current, Joule heat is successively evolved. As it is crucial to evaluate theoretically the amount of evolved heat in order to assess the effectiveness of such a system, a model describing the Joule heat evolution is proposed and a modeling example based on finite-element method is introduced.

  5. Low exhaust temperature electrically heated particulate matter filter system

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Paratore, Jr., Michael J.; Bhatia, Garima [Bangalore, IN

    2012-02-14

    A system includes a particulate matter (PM) filter, a sensor, a heating element, and a control module. The PM filter includes with an upstream end that receives exhaust gas, a downstream end and multiple zones. The sensor detects a temperature of the exhaust gas. The control module controls current to the heating element to convection heat one of the zones and initiate a regeneration process. The control module selectively increases current to the heating element relative to a reference regeneration current level when the temperature is less than a predetermined temperature.

  6. Design and performance of low-thermal-resistance, high-electrical-isolation heat intercept connections

    NASA Astrophysics Data System (ADS)

    Niemann, R. C.; Gonczy, J. D.; Phelan, P. E.; Nicol, T. H.

    Electrical conductors often require the removal of heat produced by normal operation. The heat can be removed by mechanical connection of the conductor to a refrigeration source. Such connections require both effective heat removal (low thermal resistance) and effective electrical isolation (high electrical resistance and high dielectric strength). Fabrication of these connections should be straightforward, and performance must be reliable and independent of operating temperature. The connection method described here involves clamping (by thermal interference fit) an electrically insulating cylinder between an outer metallic ring and an inner metallic disc. Material candidates for insulating cylinders include composites, e.g. epoxy/fibreglass, and ceramics, e.g. alumina. Design factors, including geometry, materials and thermal contact resistance are discussed. The design, construction experience and performance measurements of a heat intercept connection in a high-temperature superconducting lead assembly is presented.

  7. Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks

    SciTech Connect

    Larry Slone; Jeffrey Birkel

    2007-10-31

    The Advanced Electric Systems and Aerodynamics for Efficiency Improvements in Heavy Duty Trucks program (DE-FC26-04NT42189), commonly referred to as the AES program, focused on areas that will primarily benefit fuel economy and improve heat rejection while driving over the road. The AES program objectives were to: (1) Analyze, design, build, and test a cooling system that provided a minimum of 10 percent greater heat rejection in the same frontal area with no increase in parasitic fan load. (2) Realize fuel savings with advanced power management and acceleration assist by utilizing an integrated starter/generator (ISG) and energy storage devices. (3) Quantify the effect of aerodynamic drag due to the frontal shape mandated by the area required for the cooling system. The program effort consisted of modeling and designing components for optimum fuel efficiency, completing fabrication of necessary components, integrating these components into the chassis test bed, completing controls programming, and performance testing the system both on a chassis dynamometer and on the road. Emission control measures for heavy-duty engines have resulted in increased engine heat loads, thus introducing added parasitic engine cooling loads. Truck electrification, in the form of thermal management, offers technological solutions to mitigate or even neutralize the effects of this trend. Thermal control offers opportunities to avoid increases in cooling system frontal area and forestall reduced fuel economy brought about by additional aerodynamic vehicle drag. This project explored such thermal concepts by installing a 2007 engine that is compliant with current regulations and bears additional heat rejection associated with meeting these regulations. This newer engine replaced the 2002 engine from a previous project that generated less heat rejection. Advanced power management, utilizing a continuously optimized and controlled power flow between electric components, can offer additional

  8. Advanced oil burner for residential heating -- development report

    SciTech Connect

    Butcher, T.A.

    1995-07-01

    The development of advanced oil burner concepts has long been a part of Brookhaven National Laboratory`s (BNL) oil heat research program. Generally, goals of this work include: increased system efficiency, reduced emissions of soot and NO{sub x}, and the practical extension of the firing rate range of current burners to lower input rates. The report describes the results of a project at BNL aimed at the development of air atomized burners. Two concepts are discussed. The first is an air atomizer which uses air supplied at pressures ranging from 10 to 20 psi and requiring the integration of an air compressor in the system. The second, more novel, approach involves the use of a low-pressure air atomizing nozzle which requires only 8-14 inches of water air pressure for fuel atomization. This second approach requires the use of a fan in the burner instead of a compressor although the fan pressure is higher than with conventional, pressure atomized retention head burners. In testing the first concept, high pressure air atomization, a conventional retention head burner was modified to accept the new nozzle. In addition, the burner head was modified to reduce the flow area to maintain roughly 1 inch of water pressure drop across the head at a firing rate of 0.25 gallons of oil per hour. The burner ignited easily and could be operated at low excess air levels without smoke. The major disadvantage of this burner approach is the need for the air compressor as part of the system. In evaluating options, a vane-type compressor was selected although the use of a compressor of this type will lead to increased burner maintenance requirements.

  9. Experimental Study of an Advanced Plasma Thruster using ICRF Heating and Magnetic Nozzle Acceleration.

    NASA Astrophysics Data System (ADS)

    Ando, Akira

    2005-10-01

    Electric propulsion (EP) systems utilize plasma technologies and have been developed for years as one of the most promising space propulsion approaches. It is urgently required to develop high-power plasma thrusters for human expeditions to Mars and future space exploration missions. The advanced thruster is demanded to control thrust and specific impulse by adjusting the exhaust plasma density and velocity. In the VASIMR project, a combined system of efficient ion cyclotron heating and optimized magnetic nozzle design is proposed to control the ratio of specific impulse to thrust at constant power[1]. In this system a flowing plasma is heated by ICRF (ion cyclotron range of frequency) waves and the plasma thermal energy is converted to flow energy in a diverging magnetic field nozzle. We have recently performed the first demonstration of ion cyclotron resonance heating and acceleration in a magnetic nozzle by using a fast-flowing plasma with Mach number of nearly unity. Highly ionized plasma is produced by Magneto-Plasma-Dynamic thruster (MPDT). When RF power is launched by a helically-wound antenna, electromagnetic ion cyclotron waves are excited, and plasma thermal energy and ion temperature drastically increase (nearly ten-fold rise) during the RF pulse. The value of resonance magnetic field is affected by the Doppler shift due to the fast-flowing plasma. Dependences of heating efficiency on both plasma density and input RF power will be presented. Ion acceleration along the field line is also observed in a diverging magnetic field nozzle. Perpendicular component (to the magnetic field) of ion energy decreases, whereas parallel component increases along the diverging magnetic field.[1] F.R. Chang Diaz, ``The VASIMR Engine,'' AIAA 2004-0149. AIAA conf. (Reno,2004); Bulletin of APS (46th APS-DPP), NM2A-3, 2004.

  10. Materials considerations in the design of a metal-hydride heat pump for an advanced extravehicular mobility unit

    NASA Technical Reports Server (NTRS)

    Liebert, B. E.

    1986-01-01

    A metal-hydride heat pump (HHP) has been proposed to provide an advanced regenerable nonventing thermal sink for the liquid-cooled garment worn during an extravehicular activity (EVA). The conceptual design indicates that there is a potential for significant advantages over the one presently being used by shuttle crew personnel as well as those that have been proposed for future use with the space station. Compared to other heat pump designs, a HHP offers the potential for extended use with no electrical power requirements during the EVA. In addition, a reliable, compact design is possible due to the absence of moving parts other than high-reliability check valves. Because there are many subtleties in the properties of metal hydrides for heat pump applications, it is essential that a prototype hydride heat pump be constructed with the selected materials before a committment is made for the final design. Particular care must be given to the evaporator heat exchanger worn by the astronaut since the performance of hydride heat pumps is generally heat transfer limited.

  11. Diesel Engine Waste Heat Recovery Utilizing Electric Turbocompound Technology

    SciTech Connect

    Hopman, Ulrich,; Kruiswyk, Richard W.

    2005-07-05

    Caterpillar's Technology & Solutions Division conceived, designed, built and tested an electric turbocompound system for an on-highway heavy-duty truck engine. The heart of the system is a unique turbochargerr with an electric motor/generator mounted on the shaft between turbine and compressor wheels. When the power produced by the turbocharger turbine exceeds the power of the compressor, the excess power is converted to electrical power by the generator on the turbo shaft; that power is then used to help turn the crankshaft via an electric motor mounted in the engine flywheel housing. The net result is an improvement in engine fuel economy. The electric turbocompound system provides added control flexibility because it is capable of varying the amount of power extracted from the exhaust gases, thus allowing for control of engine boost. The system configuration and design, turbocharger features, control system development, and test results are presented.

  12. Recent Advances in Nuclear Powered Electric Propulsion for Space Exploration

    NASA Technical Reports Server (NTRS)

    Cassady, R. Joseph; Frisbee, Robert H.; Gilland, James H.; Houts, Michael G.; LaPointe, Michael R.; Maresse-Reading, Colleen M.; Oleson, Steven R.; Polk, James E.; Russell, Derrek; Sengupta, Anita

    2007-01-01

    Nuclear and radioisotope powered electric thrusters are being developed as primary in-space propulsion systems for potential future robotic and piloted space missions. Possible applications for high power nuclear electric propulsion include orbit raising and maneuvering of large space platforms, lunar and Mars cargo transport, asteroid rendezvous and sample return, and robotic and piloted planetary missions, while lower power radioisotope electric propulsion could significantly enhance or enable some future robotic deep space science missions. This paper provides an overview of recent U.S. high power electric thruster research programs, describing the operating principles, challenges, and status of each technology. Mission analysis is presented that compares the benefits and performance of each thruster type for high priority NASA missions. The status of space nuclear power systems for high power electric propulsion is presented. The paper concludes with a discussion of power and thruster development strategies for future radioisotope electric propulsion systems,

  13. Cost and Performance Review of Electrical Resistance Heating (ERH) for Source Treatment

    DTIC Science & Technology

    2007-03-01

    phase liquid ( DNAPL ) or high concentrations of volatile contaminants. ERH is a remediation technology that involves passing electrical current...Electrical resistant heating (ERH), Naval Facilities Engineering Service Center (NFESC), remediation, nonaqueous-phase liquid ( DNAPL ) 16. SECURITY...Camp Lejeune. Performance data from these sites indicate that ERH treats dense nonaqueous-phase liquid ( DNAPL ) source zones through a variety of

  14. Flathead Electric Cooperative Facility Geothermal Heat Pump System Upgrade.

    SciTech Connect

    Liu, Xiaobing

    2014-06-01

    High initial cost and lack of public awareness of ground source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights findings of a case study of one of the ARRA-funded GSHP demonstration projects, which is a heating only central GSHP system using shallow aquifer as heat source and installed at a warehouse and truck bay at Kalispell, MT. This case study is based on the analysis of measured performance data, utility bills, and calculations of energy consumptions of conventional central heating systems for providing the same heat outputs as the central GSHP system did. The evaluated performance metrics include energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of GSHP system compared with conventional heating systems. This case study also identified areas for reducing uncertainties in performance evaluation, improving operational efficiency, and reducing installed cost of similar GSHP systems in the future. Publication of ASHRAE at the annual conference in Seattle June 2014.

  15. Flathead Electric Cooperative Facility Geothermal Heat Pump System Upgrade

    SciTech Connect

    Liu, Xiaobing

    2014-06-01

    High initial cost and lack of public awareness of ground source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights findings of a case study of one of the ARRA-funded GSHP demonstration projects, which is a heating only central GSHP system using shallow aquifer as heat source and installed at a warehouse and truck bay at Kalispell, MT. This case study is based on the analysis of measured performance data, utility bills, and calculations of energy consumptions of conventional central heating systems for providing the same heat outputs as the central GSHP system did. The evaluated performance metrics include energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of GSHP system compared with conventional heating systems. This case study also identified areas for reducing uncertainties in performance evaluation, improving operational efficiency, and reducing installed cost of similar GSHP systems in the future. Publication of ASHRAE at the annual conference in Seattle.

  16. Identifiability of electrical and heat transfer parameters using coupled boundary measurements

    NASA Astrophysics Data System (ADS)

    Chang, Yifan

    2017-02-01

    In this paper, we show that a hybrid method using coupled boundary measurements can determine anisotropic electrical conductivity, anisotropic thermal conductivity, and the product of heat capacity and heat density within a bounded domain on the plane uniquely up to a boundary-fixing diffeomorphism.

  17. Optimization of operating parameters of endothermic generators with electric heating of retort

    NASA Astrophysics Data System (ADS)

    Dubinin, A. M.; Fink, A. V.; Kagarmanov, G. R.

    2009-07-01

    Equations of heat and gas balance of endothermic generator at air conversion of methane are used for optimizing the parameters with respect to maximum yield of hydrogen and carbon oxide at minimum consumption of electric energy for heating the retort with catalyst.

  18. The electric field in spontaneously heating accumulations of solid combustible minerals

    SciTech Connect

    Aleksandrov, I.V.

    1982-01-01

    The electric field in the ionic circuit in a spontaneously heating stack of cutter peat has been studied and modeled. On the basis of laboratory and industrial investigations and a theoretical analysis, the desirability has been shown of representing spontaneously heating accumulations of solid combustible minerals as macrogalvanic cells with spontaneous discharge.

  19. Elevated exhaust temperature, zoned, electrically-heated particulate matter filter

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN

    2012-04-17

    A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.

  20. Diesel Engine Waste Heat Recovery Utilizing Electric Turbocompound Technology

    SciTech Connect

    Gerke, Frank G.

    2001-08-05

    This cooperative program between the DOE Office of Heavy Vehicle Technology and Caterpillar, Inc. is aimed at demonstrating electric turbocompound technology on a Class 8 truck engine. This is a lab demonstration program, with no provision for on-truck testing of the system. The goal is to demonstrate the level of fuel efficiency improvement attainable with the electric turbocompound system. Also, electric turbocompounding adds an additional level of control to the air supply which could be a component in an emissions control strategy.

  1. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Allen, Bog; Delventhal, Rex; Frye, Patrick

    2004-01-01

    Recently, there has been significant interest within the aerospace community to develop space based nuclear power conversion technologies especially for exploring the outer planets of our solar system where the solar energy density is very low. To investigate these technologies NASA awarded several contracts under Project Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC).The investigation performed included BPCS (Brayton Power Conversion System) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to be capable of operation in the generic space environment and withstand the extreme environments surrounding Jupiter. The studies defined a BPCS design traceable to NEP (Nuclear Electric Propulsion) requirements and suitable for future missions with a sound technology plan for technology readiness level (TRL) advancement identified. The studies assumed a turbine inlet temperature approx. 100 C above the current the state of the art capabilities with materials issues and related development tasks identified. Analyses and evaluations of six different HRS (heat rejection system) designs and three primary power management and distribution (PMAD) configurations will be discussed in the paper.

  2. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion - Phase I

    SciTech Connect

    Frye, Patrick E.; Allen, Robert; Delventhal, Rex

    2005-02-06

    To investigate and mature space based nuclear power conversion technologies NASA awarded several contracts under Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC). The conceptual design effort performed included BPCS (Brayton power conversion system) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass (with a target of less than 3000 kg), and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to operate in the generic space environment and withstand the extreme environments within the Jovian system. The studies defined a BPCS design traceable to NBP (Nuclear Electric Propulsion) requirements and suitable for future potential missions with a sound technology plan for TRL (Technical Readiness Level) advancement identified. The studies assumed a turbine inlet temperature {approx} 100C above the current the state of the art capabilities with materials issues identified and an approach for resolution developed. Analyses and evaluations of six HRS (heat rejection subsystem) concepts and PMAD (Power Management and Distribution) architecture trades will be discussed in the paper.

  3. Protection of advanced electrical power systems from atmospheric electromagnetic hazards

    NASA Astrophysics Data System (ADS)

    Sommer, D. L.

    1981-12-01

    The effects of lightning strikes on aircraft and the resulting transients coupled onto the electrical systems were investigated. The historical background and overall scope of the study are presented. The lightning threat is defined and electrical system math models are developed. The normal design of aircraft for inherent hardness is evaluated. Wire routing, equipment location, fiber optics, threat level comparisons and the evaluation of specific electrical circuits are assessed. The effects of using add on protection to suppress induced transients on the electrical system are analyzed. Protection schemes include cable shielding, linear protection devices, nonlinear protection devices and conductive coatings applied to the aircraft skin. The design guide provides the most appropriate lightning hardening techniques is summarized. Reliability/maintainability, system safety and design to cost considerations are discussed. Protection criteria to develop a lightning tolerant electrical system are included.

  4. Heat pipe technology for advanced rocket thrust chambers

    NASA Technical Reports Server (NTRS)

    Rousar, D. C.

    1971-01-01

    The application of heat pipe technology to the design of rocket engine thrust chambers is discussed. Subjects presented are: (1) evaporator wick development, (2) specific heat pipe designs and test results, (3) injector design, fabrication, and cold flow testing, and (4) preliminary thrust chamber design.

  5. Theoretical model for the heat diffusion in an electrically calibrated laser power meter

    NASA Astrophysics Data System (ADS)

    Sporea, Dan G.; Miron, Nicolae; Dumitru, Gabriel; Timus, Bogdan

    1995-09-01

    The theoretical model for the heat diffusion in the case of a high power IR electrically calibrated laser powermeter, developed at the Institute for Atomic Physics in Bucharest, is presented. The IR laser beam falls onto a laser detector, a special design copper disc wafer which absorbs the laser beam, heats its center. A daisy-chain of thermocouple elements having one set of junctions thermally connected to the central region of the disc and the other ones to the disc's boundary is used to detect temperature rise induced by the exposure to the laser beam. For calibration, the copper disc is electrically heated and the electric power that produces the same temperature rise as one induced by an incident laser beam, should equal the laser beam power. The electric heater is designed to provide a uniform heating of the copper disc. The solution for heat diffusion equation was searched as a series of Bessel functions of zero order, the cold junction's temperature was imposed as boundary condition and the heat induced by the laser beam in the disc's center was regarded as input data. To find the correct solutions, there must be taken into account the designing elements of the copper disc: termic material's properties (caloric capacity, termic conductibility), laser detector's geometry, copper's density. The electric power for calibration was injected using a precision power injection circuit which allows a stability of the calibration power, better than 0.1%.

  6. Comparison of conceptual designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1989-01-01

    The Advanced Stirling Conversion System (ASCS) Project is managed by NASA Lewis Research Center through a cooperative interagency agreement with DOE. Conceptual designs for the ASCS's were completed under parallel contracts in 1987 by Mechanical Technology Inc. (MTI) of Latham, NY, and Stirling Technology Company (STC) of Richland, WA. Each design features a free-piston Stirling engine, a liquid metal heat pipe receiver, and a means to provide about 25 kW of electric power to a utility grid while meeting DOE's long term performance and cost goals. An independent assessment showed that both designs are manufacturable and have the potential to easily meet DOE's long term cost goals.

  7. Comparison of conceptual designs for 25 kWe advanced Stirling conversion systems for dish electric application

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1989-01-01

    The Advanced Stirling Conversion System (ASCS) Project is managed by NASA Lewis Research Center through a cooperative interagency agreement with DOE. Conceptual designs for the ASCS's were completed under parallel contracts in 1987 by Mechanical Technology Inc. (MTI) of Latham, NY, and Stirling Technology Company (STC) of Richland, WA. Each design features a free-piston Stirling engine, a liquid metal heat pipe receiver, and a means to provide about 25 kW of electric power to a utility grid while meeting DOE's long term performance and cost goals. An independent assessment showed that both designs are manufacturable and have the potential to easily meet DOE's long term cost goals.

  8. Heat pipe heat rejection system and demonstration model for the nuclear electric propulsion (NEP) spacecraft

    NASA Technical Reports Server (NTRS)

    Ernst, D. M.

    1981-01-01

    The critical evaluation and subsequent redesign of the power conversion subsystem of the spacecraft are covered. As part of that evaluation and redesign, prototype heat pipe components for the heat rejection system were designed fabricated and tested. Based on the results of these tests in conjunction with changing mission requirements and changing energy conversion devices, new system designs were investigated. The initial evaluation and redesign was based on state-of-the-art fabrication and assembly techniques for high temperature liquid metal heat pipes and energy conversion devices. The hardware evaluation demonstrated the validity of several complicated heat pipe geometries and wick structures, including an annular-to-circular transition, bends in the heat pipe, long heat pipe condensers and arterial wicks. Additionally, a heat pipe computer model was developed which describes the end point temperature profile of long radiator heat pipes to within several degrees celsius.

  9. Dynamic underground stripping: steam and electric heating for in situ decontamination of soils and groundwater

    DOEpatents

    Daily, W.D.; Ramirez, A.L.; Newmark, R.L.; Udell, K.; Buetnner, H.M.; Aines, R.D.

    1995-09-12

    A dynamic underground stripping process removes localized underground volatile organic compounds from heterogeneous soils and rock in a relatively short time. This method uses steam injection and electrical resistance heating to heat the contaminated underground area to increase the vapor pressure of the contaminants, thus speeding the process of contaminant removal and making the removal more complete. The injected steam passes through the more permeable sediments, distilling the organic contaminants, which are pumped to the surface. Large electrical currents are also applied to the contaminated area, which heat the impermeable subsurface layers that the steam has not penetrated. The condensed and vaporized contaminants are withdrawn by liquid pumping and vacuum extraction. The steam injection and electrical heating steps are repeated as necessary. Geophysical imaging methods can be used to map the boundary between the hot, dry, contamination-free underground zone and the cool, damp surrounding areas to help monitor the dynamic stripping process. 4 figs.

  10. Dynamic underground stripping: steam and electric heating for in situ decontamination of soils and groundwater

    DOEpatents

    Daily, William D.; Ramirez, Abelardo L.; Newmark, Robin L.; Udell, Kent; Buetnner, Harley M.; Aines, Roger D.

    1995-01-01

    A dynamic underground stripping process removes localized underground volatile organic compounds from heterogeneous soils and rock in a relatively short time. This method uses steam injection and electrical resistance heating to heat the contaminated underground area to increase the vapor pressure of the contaminants, thus speeding the process of contaminant removal and making the removal more complete. The injected steam passes through the more permeable sediments, distilling the organic contaminants, which are pumped to the surface. Large electrical currents are also applied to the contaminated area, which heat the impermeable subsurface layers that the steam has not penetrated. The condensed and vaporized contaminants are withdrawn by liquid pumping and vacuum extraction. The steam injection and electrical heating steps are repeated as necessary. Geophysical imaging methods can be used to map the boundary between the hot, dry, contamination-free underground zone and the cool, damp surrounding areas to help monitor the dynamic stripping process.

  11. Comparison of Advanced Residential Water Heating Technologies in the United States

    SciTech Connect

    Maguire, J.; Fang, X.; Wilson, E.

    2013-05-01

    Gas storage, gas tankless, condensing, electric storage, heat pump, and solar water heaters were simulated in several different climates across the US installed in both conditioned and unconditioned space and subjected to several different draw profiles. While many preexisting models were used, new models of condensing and heat pump water heaters were created specifically for this work.

  12. Performance improvement of a solar heating system utilizing off-peak electric auxiliary

    SciTech Connect

    Eltimsahy, A.H.

    1980-06-01

    The design and construction of a heat pump system suitable for incorporating in a space solar heating system utilizing off-peak storage from the electric utility are described. The performance of the system is evaluated. The refrigerating capacity, heating capacity and compressor horsepower for a heat pump system using a piston type compressor are first determined. The heat pump design is also matched with the existing University of Toledo solar house heating system. The refrigerant is Freon-12 working between a condensing temperature of up to 172/sup 0/F and evaporator temperature between 0/sup 0/F and 75/sup 0/F. The heat pump is then installed. Performance indices for the heat pump and the heating system in general are defined and generated by the on-line computer monitoring system for the 1979/80 heating season operation. Monthly and seasonal indices such as heat pump coefficient of performance, collector efficiency, percent of heating load supplied by solar energy and individual components efficiencies in general are recorded. The data collected is then analyzed and compared with previously collected data. The improvement in the performance resulting from the addition of a piston type compressor with an external motor belt drive is then evaluated. Data collected points to the potentially improved operating performance of a solar heating system utilizing off-peak storage from the electric utility. Data shows that the seasonal percent of space heating load supplied by solar is 60% and the seasonal percent cost of space heating load supplied by solar is 82% with a solar collection coefficient of performance of 4.6. Data also indicates that such a system would pay for itself in 14 years when used in Northwest Ohio.

  13. Development and Analysis of Advanced High-Temperature Technology for Nuclear Heat Transport and Power Conversion

    SciTech Connect

    Per F. Peterson

    2010-03-01

    This project by the Thermal Hydraulics Research Laboratory at U.C. Berkeley Studied advanced high-temperature heat transport and power conversion technology, in support of the Nuclear Hydrogen Initiative and Generation IV.

  14. Effects of air velocity and clothing combination on heating efficiency of an electrically heated vest (EHV): a pilot study.

    PubMed

    Wang, Faming; Gao, Chuansi; Holmér, Ingvar

    2010-09-01

    Cold endangers the heat balance of the human body. Protective clothing is the natural and most common equipment against cold stress. However, clothing for cold protection may be bulky and heavy, affecting human performance and increasing the work load. In such cases, a heated garment with built-in heating elements may be helpful. This pilot study presents a method based on a thermal manikin to investigate the effects of air velocity and clothing combination on the heating efficiency of an electrically heated vest (EHV). An infrared thermal camera was used to detect surface temperature distributions of the EHV on the front and back. Results show that the heating efficiency of the EHV decreases with increasing air velocity. Changes in EHV sequence in the three-layer clothing combination also significantly affect the heating efficiency: it increases with the increasing number of layers on top of the EHV. The highest mean temperature on the inner surface of the EHV was 40.2 degrees C, which indicates that it is safe for the wearers. For the EHV to heat the human body effectively, we suggest that it be worn as a middle layer. Finally, the EHV is especially suitable for occupational groups whose metabolic rate is below 1.9 Mets.

  15. Radiative properties of advanced spacecraft heat shield materials

    NASA Technical Reports Server (NTRS)

    Cunnington, G. R.; Funai, A. I.; Mcnab, T. K.

    1983-01-01

    Experimental results are presented to show the effects of simulated reentry exposure by convective heating and by radiant heating on spectral and total emittance of statically oxidized Inconel 617 and Haynes HS188 superalloys to 1260 K and a silicide coatea (R512E) columbium 752 alloy to 1590 K. Convective heating exposures were conducted in a supersonic arc plasma wind tunnel using a wedge-shaped specimen configuration. Radiant tests were conducted at a pressure of .003 atmospheres of dry air at a flow velocity of several meters per second. Convective heating specimens were subjected to 8, 20, and 38 15-min heating cycles, and radiant heating specimens were tested for 10, 20, 50, and 100 30-min heating cycles. Changes in radiative properties are explained in terms of changes in composition resulting from simulated reentry tests. The methods used to evaluate morphological, compositional and crystallographic changes include: Auger electron spectroscopy; scanning electron microscopy; X-ray diffraction analysis; and electron microprobe analysis.

  16. The Tensile Properties of Advanced Nickel-Base Disk Superalloys During Quenching Heat Treatments

    NASA Technical Reports Server (NTRS)

    Gabb, Timothy P.; Gayda, John; Kantzos, Pete T.; Biles, Tiffany; Konkel, William

    2001-01-01

    There is a need to increase the temperature capabilities of superalloy turbine disks. This would allow full utilization of higher temperature combustor and airfoil concepts under development. One approach to meet this goal is to modify the processing and chemistry of advanced alloys, while preserving the ability to use rapid cooling supersolvus heat treatments to achieve coarse grain, fine gamma prime microstructures. An important step in this effort is to understand the key high temperature tensile properties of advanced alloys as they exist during supersolvus heat treatments. This could help in projecting cracking tendencies of disks during quenches from supersolvus heat treatments. The objective of this study was to examine the tensile properties of two advanced disk superalloys during simulated quenching heat treatments. Specimens were cooled from the solution heat treatment temperatures at controlled rates, interrupted, and immediately tensile tested at various temperatures. The responses and failure modes were compared and related to the quench cracking tendencies of disk forgings.

  17. Electrically heated particulate filter with zoned exhaust flow control

    SciTech Connect

    Gonze, Eugene V

    2012-06-26

    A system includes a particulate matter (PM) filter that includes X zones. An electrical heater includes Y heater segments that are associated with respective ones of the X zones. The electrical heater is arranged upstream from and proximate with the PM filter. A valve assembly includes Z sections that are associated with respective ones of the X zones. A control module adjusts flow through each of the Z sections during regeneration of the PM filter via control of the valve assembly. X, Y and Z are integers.

  18. Electrical conductivity and physical properties of surimi-potato starch under ohmic heating.

    PubMed

    Pongviratchai, P; Park, J W

    2007-11-01

    Electrical conductivities of Alaska pollock surimi mixed with native and pregelled potato starch at different concentrations (0%, 3%, and 9%) were measured at different moisture contents (75% and 81%) using a multifrequency ohmic heating system. Surimi-starch paste was tested up to 80 degrees C at frequencies from 55 Hz to 20 KHz and at alternating currents of 4.3 and 15.5 V/cm voltage gradient. Electrical conductivity increased when moisture content, applied frequency, and applied voltage increased, but decreased when starch concentration increased. Electrical conductivity was correlated linearly with temperature (R(2) approximately 0.99). Electrical conductivity pattern (magnitude) changed when temperature increased, which was clearly seen after 55 degrees C in the native potato starch system, especially at high concentration. This confirms that starch gelatinization that occurred during heating affects the electrical conductivity. Whiteness and texture properties decreased with an increase of starch concentration and a decrease of moisture content.

  19. Local Heat Transfer to an Evaporating Sessile Droplet in an Electric Field

    NASA Astrophysics Data System (ADS)

    Gibbons, M. J.; Howe, C. M.; Di Marco, P.; Robinson, A. J.

    2016-09-01

    Local heat transfer of an evaporating sessile droplet under a static electric field is an underdeveloped topic. In this research an 80 μl water droplet is placed in the centre of a 25 μm thick stainless steel substrate. A static electric field is applied by an electrode positioned 10 mm above the substrate. A high speed thermal imaging camera is placed below the substrate to capture the thermal footprint of the evaporating droplet. Four electric fields were characterised; 0, 5, 10 and 11 kV/cm. As the electric field is increased the contact angle was observed to decrease. The local heat flux profile, peak and radial location of this peek were observed to be independent of the applied electric field for all test points for this working fluid and surface combination.

  20. Assessment of Feasibility of the Beneficial Use of Waste Heat from the Advanced Test Reactor

    SciTech Connect

    Donna P. Guillen

    2012-07-01

    This report investigates the feasibility of using waste heat from the Advanced Test Reactor (ATR). A proposed glycol waste heat recovery system was assessed for technical and economic feasibility. The system under consideration would use waste heat from the ATR secondary coolant system to preheat air for space heating of TRA-670. A tertiary coolant stream would be extracted from the secondary coolant system loop and pumped to a new plate and frame heat exchanger, where heat would be transferred to a glycol loop for preheating outdoor air in the heating and ventilation system. Historical data from Advanced Test Reactor operations over the past 10 years indicates that heat from the reactor coolant was available (when needed for heating) for 43.5% of the year on average. Potential energy cost savings by using the waste heat to preheat intake air is $242K/yr. Technical, safety, and logistics considerations of the glycol waste heat recovery system are outlined. Other opportunities for using waste heat and reducing water usage at ATR are considered.

  1. Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System

    PubMed Central

    Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

    2017-01-01

    Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer. PMID:28145516

  2. Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System.

    PubMed

    Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

    2017-02-01

    Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer.

  3. Bench-scale testing of a heat-pipe receiver for solar thermal electric applications

    NASA Astrophysics Data System (ADS)

    Adkins, Douglas R.; Dudley, Vernon

    Electric power generating systems that couple parabolic-dish solar-concentrators with Stirling engines and generators are currently being developed under the Department of Energy's solar thermal electric program. These systems will use liquid metal heat pipes to transfer energy from the focal point of a solar concentrator to the heater tubes of a Stirling engine. The heat-pipe solar-receivers are required to operate in adverse orientations and accept flux levels on the order of 100 W/sq. cm. To explore the operating limits of heat-pipe solar-receivers, a series of bench-scale heat pipe receivers are being designed and tested. Results from the bench-scale tests and their implications on a full-scale heat-pipe solar receiver are presented in this paper.

  4. Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System

    NASA Astrophysics Data System (ADS)

    Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

    2017-02-01

    Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer.

  5. Advanced design concepts in nuclear electric propulsion. [and spacecraft configurations

    NASA Technical Reports Server (NTRS)

    Peelgren, M. L.; Mondt, J. F.

    1974-01-01

    Conceptual designs of the nuclear propulsion programs are reported. Major areas of investigation were (1) design efforts on spacecraft configuration and heat rejection subsystem, (2) high-voltage thermionic reactor concepts, and (3) dual-mode spacecraft configuration study.

  6. Liquid cooled plate heat exchanger for battery cooling of an electric vehicle (EV)

    NASA Astrophysics Data System (ADS)

    Rahman, M. M.; Rahman, H. Y.; Mahlia, T. M. I.; Sheng, J. L. Y.

    2016-03-01

    A liquid cooled plate heat exchanger was designed to improve the battery life of an electric vehicle which suffers from premature aging or degradation due to the heat generation during discharging and charging period. Computational fluid dynamics (CFD) was used as a tool to analyse the temperature distribution when a constant surface heat flux was set at the bottom surface of the battery. Several initial and boundary conditions were set based on the past studies on the plate heat exchanger in the simulation software. The design of the plate heat exchanger was based on the Nissan Leaf battery pack to analyse the temperature patterns. Water at different mass flow rates was used as heat transfer fluid. The analysis revealed the designed plate heat exchanger could maintain the surface temperature within the range of 20 to 40°C which is within the safe operating temperature of the battery.

  7. Electric Materials in advance of Technologies for CO2 Emission Mitigation

    NASA Astrophysics Data System (ADS)

    Tanaka, Yasuzo

    Electric materials for the CO2 emission reduction and the climate changes mitigation are reviewed for this special issue. In the diversified society and the climate changes in the global environment, the advanced electric materials and their effective application technologies are a significant and argent field. Proceedings of superconducting materials, fuel cell materials, solar cell materials etc. are spectacular.

  8. Kohlrausch Heat Conductivity Apparatus for Intermediate or Advanced Laboratory

    ERIC Educational Resources Information Center

    Jensen, H. G.

    1970-01-01

    Describes student experiment in measuring heat conductivity according to Kohlrausch's method. Theory, apparatus design, and experimental procedure is outlined. Results for copper are consistent to within 2 percent. (LC)

  9. Advanced turbine cooling, heat transfer, and aerodynamic studies

    SciTech Connect

    Je-Chin Han; Schobeiri, M.T.

    1995-10-01

    The contractual work is in three parts: Part I - Effect of rotation on enhanced cooling passage heat transfer, Part II - Effect on Thermal Barrier Coating (TBC) spallation on surface heat transfer, and Part III - Effect of surface roughness and trailing edge ejection on turbine efficiency under unsteady flow conditions. Each section of this paper has been divided into three parts to individually accommodate each part. Part III is further divided into Parts IIIa and IIIb.

  10. Advanced turbine cooling, heat transfer, and aerodynamic studies

    SciTech Connect

    Han, Je-Chin; Schobeiri, M.T.

    1995-12-31

    The contractual work is in three parts: Part I - Effect of rotation on enhanced cooling passage heat transfer, Part II - Effect of Thermal Barrier Coating (TBC) spallation on surface heat transfer, and Part III - Effect of surface roughness and trailing edge ejection on turbine efficiency under unsteady flow conditions. Each section of this paper has been divided into three parts to individually accommodate each part. Part III is further divided into Parts IIIa and IIIb.

  11. Advanced sensible heat solar receiver for space power

    NASA Technical Reports Server (NTRS)

    Bennett, Timothy J.; Lacy, Dovie E.

    1988-01-01

    NASA Lewis, through in-house efforts, has begun a study to generate a conceptual design of a sensible heat solar receiver and to determine the feasibility of such a system for space power applications. The sensible heat solar receiver generated in this study uses pure lithium as the thermal storage medium and was designed for a 7 kWe Brayton (PCS) operating at 1100 K. The receiver consists of two stages interconnected via temperature sensing variable conductance sodium heat pipes. The lithium is contained within a niobium vessel and the outer shell of the receiver is constructed of third generation rigid, fibrous ceramic insulation material. Reradiation losses are controlled with niobium and aluminum shields. By nature of design, the sensible heat receiver generated in this study is comparable in both size and mass to a latent heat system of similar thermal capacitance. The heat receiver design and thermal analysis was conducted through the combined use of PATRAN, SINDA, TRASYS, and NASTRAN software packages.

  12. Advanced sensible heat solar receiver for space power

    NASA Technical Reports Server (NTRS)

    Bennett, Timothy J.; Lacy, Dovie E.

    1988-01-01

    NASA Lewis, through in-house efforts, has begun a study to generate a conceptual design of a sensible heat solar receiver and to determine the feasibility of such a system for space power applications. The sensible heat solar receiver generated in this study uses pure lithium as the thermal storage medium and was designed for a 7 kWe Brayton (PCS) operating at 1100 K. The receiver consists of two stages interconnected via temperature sensing variable conductance sodium heat pipes. The lithium is contained within a niobium vessel and the outer shell of the receiver is constructed of third generation rigid, fibrous ceramic insulation material. Reradiation losses are controlled with niobium and aluminum shields. By nature of design, the sensible heat receiver generated in this study is comparable in both size and mass to a latent heat system of similar thermal capacitance. The heat receiver design and thermal analysis were conducted through the combined use of PATRAN, SINDA, TRASYS, and NASTRAN software packages.

  13. An Advanced Loop Heat Pipe for Cryogenic Applications

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Hoang, Triem

    2016-01-01

    A loop heat pipe (LHP) is a very versatile heat transfer device which can transport a large heat load over a long distance with a small temperature difference. All LHPs currently servicing orbiting spacecraft are designed to operate in the room temperature range. Future space telescopes and space-based Earth resource imaging satellites require passive cryogenic heat transport devices that can thermally couple remote cryocoolers to sensor or instrument of interest while providing the capability of payload vibration/jitter isolation, implementation of redundant coolers, and coupling of multiple sensors to a common heat sink. All of these requirements can be satisfied by using a cryogenic LHP (CLHP). Although the development of CLHPs faces several technical challenges, NASA Goddard Space Flight Center has devoted extensive efforts in developing CLHP technology over the past decade and has made significant progress. In particular, the combination of the innovative ideas of using a secondary capillary pump to manage the parasitic heat gain and using a hot reservoir to reduce the system pressure under the ambient condition has led to the successful development of the CLHP. Several CLHPs charged with nitrogen and hydrogen were built and tested in thermal vacuum chambers. These CLHPs demonstrated reliable start-up and robust operation during power cycle and sink temperature cycle tests.

  14. Usage possibilities of diesel aggregate for room heating and electric energy production

    SciTech Connect

    Kegl, K.; Vor Ic, J.

    1998-07-01

    Article shows reasons for introduction of cogeneration generally. The present manner of heating and electricity connection at the Faculty of electrical engineering and computer science in Maribor is described. The idea is to build in the cogeneration complex in heating room next to the existent boilers. Gathered data of electricity and heat demand are presented. Paper deals with question of electrical, heat and fuel connections. Comparison between two types of cogeneration (motor and turbine) helps to make a decision: cogeneration with motor. Depending to the daily electricity demands diagram and arranged heating diagram the authors focused to the small cogeneration (around 200 kWe). Availability of natural gas at the placement of the cogeneration leads us to the gas motor but leaves the diesel engine possibility opened. A brief economical estimation includes common investment costs regarding to the savings of energy and fuel expenses. Payback time calculation gives precedence to the gas motor if diesel is used with motor instead of fuel oil. Except the energy savings there are greater benefits of the cogeneration: it can be good study case for students of electrotechnics as well as future mechanical engineers.

  15. 77 FR 56241 - Notice of Withdrawal of Final Design Approval; Westinghouse Electric Company; Advanced Passive 1000

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ... COMMISSION Notice of Withdrawal of Final Design Approval; Westinghouse Electric Company; Advanced Passive.... Nuclear Regulatory Commission (NRC or the Commission) ``retire'' the final design approval (FDA) for the Advanced Passive 1000 (AP1000) design upon the completion of rulemaking for the amendment to the...

  16. Comparative effects of ohmic, induction cooker, and electric stove heating on soymilk trypsin inhibitor inactivation.

    PubMed

    Lu, Lu; Zhao, Luping; Zhang, Caimeng; Kong, Xiangzhen; Hua, Yufei; Chen, Yeming

    2015-03-01

    During thermal treatment of soymilk, a rapid incorporation of Kunitz trypsin inhibitor (KTI) into protein aggregates by covalent (disulfide bond, SS) and/or noncovalent interactions with other proteins is responsible for its fast inactivation of trypsin inhibitor activity (TIA). In contrast, the slow cleavage of a single Bowman-Birk inhibitor (BBI) peptide bond is responsible for its slow inactivation of TIA and chymotrypsin inhibitor activity (CIA). In this study, the effects of Ohmic heating (220 V, 50 Hz) on soymilk TIA and CIA inactivation were examined and compared to induction cooker and electric stove heating with similar thermal histories. It was found that: (1) TIA and CIA inactivation was slower from 0 to 3 min, and faster after 3 min as compared to induction cooker and electric stove. (2) The thiol (SH) loss rate was slower from 0 to 3 min, and similar to induction cooker and electric stove after 3 min. (3) Ohmic heating slightly increased protein aggregate formation. (4) In addition to the cleavage of one BBI peptide bond, an additional reaction might occur to enhance BBI inactivation. (5) Ohmic heating was more energy-efficient for TIA and CIA inactivation. (6) TIA and CIA inactivation was accelerated with increasing electric voltage (110, 165, and 220 V) of Ohmic heating. It is likely that the enhanced inactivation of TIA by Ohmic heating is due to its combined electrochemical and thermal effects.

  17. Electric currents and coronal heating in NOAA active region 6952

    NASA Technical Reports Server (NTRS)

    Metcalf, T. R.; Canfield, R. C.; Hudson, H. S.; Mickey, D. L.; Wulser, J. -P.; Martens, P. C. H.; Tsuneta, S.

    1994-01-01

    We examine the spatial and temporal relationship between coronal structures observed with the soft X-ray telescope (SXT) on board the Yohkoh spacecraft and the vertical electric current density derived from photospheric vector magnetograms obtained using the Stokes Polarimeter at the Mees Solar Observatory. We focus on a single active region: AR 6952 which we observed on 7 days during 1991 December. For 11 independent maps of the vertical electric current density co-aligned with non-flaring X-ray images, we search for a morphological relationship between sites of high vertical current density in the photosphere and enhanced X-ray emission in the overlying corona. We find no compelling spatial or temporal correlation between the sites of vertical current and the bright X-ray structures in this active region.

  18. High exhaust temperature, zoned, electrically-heated particulate matter filter

    DOEpatents

    Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima

    2015-09-22

    A system includes a particulate matter (PM) filter, an electric heater, and a control circuit. The electric heater includes multiple zones, which each correspond to longitudinal zones along a length of the PM filter. A first zone includes multiple discontinuous sub-zones. The control circuit determines whether regeneration is needed based on an estimated level of loading of the PM filter and an exhaust flow rate. In response to a determination that regeneration is needed, the control circuit: controls an operating parameter of an engine to increase an exhaust temperature to a first temperature during a first period; after the first period, activates the first zone; deactivates the first zone in response to a minimum filter face temperature being reached; subsequent to deactivating the first zone, activates a second zone; and deactivates the second zone in response to the minimum filter face temperature being reached.

  19. Structure for conversion of solar radiation to electricity and heat

    SciTech Connect

    Boling, N.L.; Rapp, C.F.

    1980-01-29

    Disclosed is a modified flat plate thermal collector, modified to substitute for one of its insulating flat light conducting members a flat luminescent solar collector plate coupled to a photocell and having a thin layer containing a luminescent species responsive to solar radiation, to provide a structure for producing both electrical and thermal energy, wherein said thin layer is protected from the ambient atmosphere and wherein the thin layer is out of contact with said photocell.

  20. Space Power Architectures for NASA Missions: The Applicability and Benefits of Advanced Power and Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.

    2001-01-01

    The relative importance of electrical power systems as compared with other spacecraft bus systems is examined. The quantified benefits of advanced space power architectures for NASA Earth Science, Space Science, and Human Exploration and Development of Space (HEDS) missions is then presented. Advanced space power technologies highlighted include high specific power solar arrays, regenerative fuel cells, Stirling radioisotope power sources, flywheel energy storage and attitude control, lithium ion polymer energy storage and advanced power management and distribution.

  1. Thermal Protection System (Heat Shield) Development - Advanced Development Project

    NASA Technical Reports Server (NTRS)

    Kowal, T. John

    2010-01-01

    The Orion Thermal Protection System (TPS) ADP was a 3 1/2 year effort to develop ablative TPS materials for the Orion crew capsule. The ADP was motivated by the lack of available ablative TPS's. The TPS ADP pursued a competitive phased development strategy with succeeding rounds of development, testing and down selections. The Project raised the technology readiness level (TRL) of 8 different TPS materials from 5 different commercial vendors, eventual down selecting to a single material system for the Orion heat shield. In addition to providing a heat shield material and design for Orion on time and on budget, the Project accomplished the following: 1) Re-invigorated TPS industry & re-established a NASA competency to respond to future TPS needs; 2) Identified a potentially catastrophic problem with the planned MSL heat shield, and provided a viable, high TRL alternate heat shield design option; and 3) Transferred mature heat shield material and design options to the commercial space industry, including TPS technology information for the SpaceX Dragon capsule.

  2. Advanced Design Heat PumpRadiator for EVA Suits

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Chen, Weibo; Passow, Christian; Phillips, Scott; Trevino, Luis

    2009-01-01

    Absorption cooling using a LiCl/water heat pump can enable lightweight and effective thermal control for EVA suits without venting water to the environment. The key components in the system are an absorber/radiator that rejects heat to space and a flexible evaporation cooling garment that absorbs heat from the crew member. This paper describes progress in the design, development, and testing of the absorber/radiator and evaporation cooling garment. New design concepts and fabrication approaches will significantly reduce the mass of the absorber/radiator. We have also identified materials and demonstrated fabrication approaches for production of a flexible evaporation cooling garment. Data from tests of the absorber/radiator s modular components have validated the design models and allowed predictions of the size and weight of a complete system.

  3. Advanced radiator concepts utilizing honeycomb panel heat pipes (stainless steel)

    NASA Astrophysics Data System (ADS)

    Fleischman, G. L.; Tanzer, H. J.

    1985-08-01

    The feasibility of fabricating and processing moderate temperature range heat pipes in a low mass honeycomb sandwich panel configuration for highly efficient radiator fins for the NASA space station was investigated. A variety of honeycomb panel facesheet and core-ribbon wick concepts were evaluated within constraints dictated by existing manufacturing technology and equipment. Concepts evaluated include: type of material, material and panel thicknesses, wick type and manufacturability, liquid and vapor communication among honeycomb cells, and liquid flow return from condenser to evaporator facesheet areas. In addition, the overall performance of the honeycomb panel heat pipe was evaluated analytically.

  4. Advanced radiator concepts utilizing honeycomb panel heat pipes (stainless steel)

    NASA Technical Reports Server (NTRS)

    Fleischman, G. L.; Tanzer, H. J.

    1985-01-01

    The feasibility of fabricating and processing moderate temperature range heat pipes in a low mass honeycomb sandwich panel configuration for highly efficient radiator fins for the NASA space station was investigated. A variety of honeycomb panel facesheet and core-ribbon wick concepts were evaluated within constraints dictated by existing manufacturing technology and equipment. Concepts evaluated include: type of material, material and panel thicknesses, wick type and manufacturability, liquid and vapor communication among honeycomb cells, and liquid flow return from condenser to evaporator facesheet areas. In addition, the overall performance of the honeycomb panel heat pipe was evaluated analytically.

  5. Advanced Computational Methods for Thermal Radiative Heat Transfer

    SciTech Connect

    Tencer, John; Carlberg, Kevin Thomas; Larsen, Marvin E.; Hogan, Roy E.

    2016-10-01

    Participating media radiation (PMR) in weapon safety calculations for abnormal thermal environments are too costly to do routinely. This cost may be s ubstantially reduced by applying reduced order modeling (ROM) techniques. The application of ROM to PMR is a new and unique approach for this class of problems. This approach was investigated by the authors and shown to provide significant reductions in the computational expense associated with typical PMR simulations. Once this technology is migrated into production heat transfer analysis codes this capability will enable the routine use of PMR heat transfer in higher - fidelity simulations of weapon resp onse in fire environments.

  6. Electrically tunable near-field radiative heat transfer via ferroelectric materials

    SciTech Connect

    Huang, Yi; Boriskina, Svetlana V.; Chen, Gang

    2014-12-15

    We explore ways to actively control near-field radiative heat transfer between two surfaces that relies on electrical tuning of phonon modes of ferroelectric materials. Ferroelectrics are widely used for tunable electrical devices, such as capacitors and memory devices; however, their tunable properties have not yet been examined for heat transfer applications. We show via simulations that radiative heat transfer between two ferroelectric materials can be enhanced by over two orders of magnitude over the blackbody limit in the near field, and can be tuned as much as 16.5% by modulating the coupling between surface phonon polariton modes at the two surfaces via varying external electric fields. We then discuss how to maximize the modulation contrast for tunable thermal devices using the studied mechanism.

  7. Advanced batteries for electric vehicles-A status report

    SciTech Connect

    Walsh, W.J.

    1981-01-01

    The candidate battery systems for electric vehicles have been evaluated on a common basis. The batteries with the highest probability of successful development and commercialization appear to be lead-acid, nickel-iron, nickel-zinc, zinc-chlorine, lithium-metal sulfide, and sodium sulfur. The relative development risk was assessed and compared to the desirability of the corresponding batteries.

  8. Advanced Electric Distribution, Switching, and Conversion Technology for Power Control

    NASA Technical Reports Server (NTRS)

    Soltis, James V.

    1998-01-01

    The Electrical Power Control Unit currently under development by Sundstrand Aerospace for use on the Fluids Combustion Facility of the International Space Station is the precursor of modular power distribution and conversion concepts for future spacecraft and aircraft applications. This unit combines modular current-limiting flexible remote power controllers and paralleled power converters into one package. Each unit includes three 1-kW, current-limiting power converter modules designed for a variable-ratio load sharing capability. The flexible remote power controllers can be used in parallel to match load requirements and can be programmed for an initial ON or OFF state on powerup. The unit contains an integral cold plate. The modularity and hybridization of the Electrical Power Control Unit sets the course for future spacecraft electrical power systems, both large and small. In such systems, the basic hybridized converter and flexible remote power controller building blocks could be configured to match power distribution and conversion capabilities to load requirements. In addition, the flexible remote power controllers could be configured in assemblies to feed multiple individual loads and could be used in parallel to meet the specific current requirements of each of those loads. Ultimately, the Electrical Power Control Unit design concept could evolve to a common switch module hybrid, or family of hybrids, for both converter and switchgear applications. By assembling hybrids of a common current rating and voltage class in parallel, researchers could readily adapt these units for multiple applications. The Electrical Power Control Unit concept has the potential to be scaled to larger and smaller ratings for both small and large spacecraft and for aircraft where high-power density, remote power controllers or power converters are required and a common replacement part is desired for multiples of a base current rating.

  9. An assessment of research and development leadership in advanced batteries for electric vehicles

    SciTech Connect

    Bruch, V.L.

    1994-02-01

    Due to the recently enacted California regulations requiring zero emission vehicles be sold in the market place by 1998, electric vehicle research and development (R&D) is accelerating. Much of the R&D work is focusing on the Achilles` heel of electric vehicles -- advanced batteries. This report provides an assessment of the R&D work currently underway in advanced batteries and electric vehicles in the following countries: Denmark, France, Germany, Italy, Japan, Russia, and the United Kingdom. Although the US can be considered one of the leading countries in terms of advanced battery and electric vehicle R&D work, it lags other countries, particularly France, in producing and promoting electric vehicles. The US is focusing strictly on regulations to promote electric vehicle usage while other countries are using a wide variety of policy instruments (regulations, educational outreach programs, tax breaks and subsidies) to encourage the use of electric vehicles. The US should consider implementing additional policy instruments to ensure a domestic market exists for electric vehicles. The domestic is the largest and most important market for the US auto industry.

  10. A Course in Advanced Topics in Heat and Mass Transfer.

    ERIC Educational Resources Information Center

    Shaeiwitz, Joseph A.

    1983-01-01

    A three or four semester-hour graduate course was designed to provide basic instruction in heat/mass transfer topics relevant to chemical engineering problems and to train students to develop mathematical descriptions for new situations encountered in problem-solving. Course outline and list of references used in the course are provided. (JM)

  11. Test Method Designed to Evaluate Cylinder Liner-Piston Ring Coatings for Advanced Heat Engines

    NASA Technical Reports Server (NTRS)

    Radil, Kevin C.

    1997-01-01

    Research on advanced heat engine concepts, such as the low-heat-rejection engine, have shown the potential for increased thermal efficiency, reduced emissions, lighter weight, simpler design, and longer life in comparison to current diesel engine designs. A major obstacle in the development of a functional advanced heat engine is overcoming the problems caused by the high combustion temperatures at the piston ring/cylinder liner interface, specifically at top ring reversal (TRR). Therefore, advanced cylinder liner and piston ring materials are needed that can survive under these extreme conditions. To address this need, researchers at the NASA Lewis Research Center have designed a tribological test method to help evaluate candidate piston ring and cylinder liner materials for advanced diesel engines.

  12. Thermal conductivity, electrical conductivity and specific heat of copper-carbon fiber composite

    NASA Technical Reports Server (NTRS)

    Kuniya, Keiichi; Arakawa, Hideo; Kanai, Tsuneyuki; Chiba, Akio

    1988-01-01

    A new material of copper/carbon fiber composite is developed which retains the properties of copper, i.e., its excellent electrical and thermal conductivity, and the property of carbon, i.e., a small thermal expansion coefficient. These properties of the composite are adjustable within a certain range by changing the volume and/or the orientation of the carbon fibers. The effects of carbon fiber volume and arrangement changes on the thermal and electrical conductivity, and specific heat of the composite are studied. Results obtained are as follows: the thermal and electrical conductivity of the composite decrease as the volume of the carbon fiber increases, and were influenced by the fiber orientation. The results are predictable from a careful application of the rule of mixtures for composites. The specific heat of the composite was dependent, not on fiber orientation, but on fiber volume. In the thermal fatigue tests, no degradation in the electrical conductivity of this composite was observed.

  13. Monitoring radio-frequency heating of contaminated soils using electrical resistance tomography

    SciTech Connect

    Ramirez, A.L.; Daily, W.D.

    1993-09-01

    Electrical resistance tomography (ERT) was used to monitor a radio-frequency heating process for the insitu remediation of volatile organic compounds from subsurface water and soil at the Savannah River Site, near Aiken, South Carolina. A dipole antenna located in a horizontal well in the unsaturated zone was used to heat a contaminated clay layer. The heat-induced changes were tomographically imaged by their effects on the formation electrical resistivity. The resistivity changes observed appear to be related to heating and vaporization of the pore water, formation of steam condensate, and infiltration of rainwater through the heated zones and adjacent areas. There is a clear asymmetry downward in the resistivity decreases associated with the heating process. The resistivity decreases observed in the vicinity of the heating well are believed to be caused by the heating and downward migration of warm water originally located within a radius of a few feet around the heating well; the magnitude of the change is between 10--20%. The decreasing resistivity implies an increasing rate of radio wave attenuation as heating progressed; therefore, the rate of energy deposition around the heating well increased while the penetration distance of the radio waves decreased. Saturation changes in the clay near the antenna during heating were estimated to be 50--55% based on the observed resistivity decreases. Resistivity changes observed at distances greater than 3 meters to one side of the antenna appear to be related to rainwater infiltration. We propose that gaps in near surface clay layers allow rainwater to migrate downward and reach the top of clay rich zone penetrated by the antenna borehole. The water may then accumulate along the top of the clay.

  14. Electric current heating calibration of a laser holographic nondestructive test system

    NASA Technical Reports Server (NTRS)

    Liu, H.-K.; Kurtz, R. L.

    1975-01-01

    Holographic NDT was used to measure small surface displacements controlled by electric heating by detecting the difference of the interference fringe patterns as viewed through the hologram on a real time basis. A perforated aluminum test plate, with the holes used to position thin metal foils, was used in the experiment. One of the foils was connected to an electric power source and small displacements of the foil were caused and controlled by Ohmic heating. An He-Ne laser was used to perform the holography.

  15. Electrocaloric cooling: The importance of electric-energy recovery and heat regeneration

    NASA Astrophysics Data System (ADS)

    Plaznik, U.; Vrabelj, M.; Kutnjak, Z.; Malič, B.; Poredoš, A.; Kitanovski, A.

    2015-09-01

    Here we explore the effect of electric-energy recovery and heat regeneration on the energy efficiency of an electrocaloric-cooling system. Furthermore, the influence of the polarization-electric field hysteresis on the energy efficiency of the system is analysed. For the purposes of the analysis, the properties of (1 - x)Pb(Mg1/3Nb2/3)O3-x PbTiO3 (PMN-100xPT) with x = 0, x=0.1 , and x=0.35 are characterized. We show that if no heat is regenerated, even small irreversibilities in the electric circuit used to recover the electric energy can cause a significant drop in the achievable energy efficiency. On the other hand, when a heat regeneration process is considered and a realistic value for the degree of electric-energy recovery equal to 80% is assumed, the limit for the energy efficiency of a system employing PMN ceramics is estimated to be equal to 81% of the efficiency of a Carnot heat pump.

  16. Influence of electrical and hybrid heating on bread quality during baking.

    PubMed

    Chhanwal, N; Ezhilarasi, P N; Indrani, D; Anandharamakrishnan, C

    2015-07-01

    Energy efficiency and product quality are the key factors for any food processing industry. The aim of the study was to develop energy and time efficient baking process. The hybrid heating (Infrared + Electrical) oven was designed and fabricated using two infrared lamps and electric heating coils. The developed oven can be operated in serial or combined heating modes. The standardized baking conditions were 18 min at 220°C to produce the bread from hybrid heating oven. Effect of baking with hybrid heating mode (H-1 and H-2, hybrid oven) on the quality characteristics of bread as against conventional heating mode (C-1, pilot scale oven; C-2, hybrid oven) was studied. The results showed that breads baked in hybrid heating mode (H-2) had higher moisture content (28.87%), higher volume (670 cm(3)), lower crumb firmness value (374.6 g), and overall quality score (67.0) comparable to conventional baking process (68.5). Moreover, bread baked in hybrid heating mode showed 28% reduction in baking time.

  17. Direct Electricity from Heat: A Solution to Assist Aircraft Power Demands

    NASA Technical Reports Server (NTRS)

    Goldsby, Jon C.

    2010-01-01

    A thermionic device produces an electrical current with the application of a thermal gradient whereby the temperature at one electrode provides enough thermal energy to eject electrons. The system is totally predicated on the thermal gradient and the work function of the electrode collector relative to the emitter electrode. Combined with a standard thermoelectric device high efficiencies may result, capable of providing electrical energy from the waste heat of gas turbine engines.

  18. Diesel particulate filter (DPF) regeneration by electrical heating of resistive coatings

    DOEpatents

    Williamson, Weldon S.; Gonze, Eugene V.

    2008-12-30

    An exhaust system that processes exhaust generated by an engine includes a diesel particulate filter (DPF) that is disposed downstream of the engine and that filters particulates from the exhaust. An electrical heater is integrally formed in an upstream end of the DPF and selectively heats the exhaust to initiate combustion of the particulates within the exhaust as it passes therethrough. Heat generated by combustion of the particulates induces combustion of particulates within the DPF.

  19. Electrically heated tube investigation of cooling channel geometry effects

    NASA Technical Reports Server (NTRS)

    Meyer, Michael L.

    1995-01-01

    The results of an experimental investigation on the combined effects of cooling channel aspect ratio and curvature for rocket engines are presented. Symmetrically heated tubes with average heat fluxes up to 1.7 MW/m(exp 2) were used. The coolant was gaseous nitrogen at an inlet temperature of 280 K (500 R) and inlet pressures up to 1.0 x 10(exp 7) N/m(exp 2) (1500 psia). Two different tube geometries were tested: a straight, circular cross-section tube, and an aspect-ratio 10 cross-section tube with a 45 deg bend. The circular tube results are compared to classical models from the literature as validation of the system. The curvature effect data from the curved aspect-ratio 10 tube compare favorably to the empirical equations available in the literature for low aspect ratio tubes. This latter results suggest that thermal stratification of the coolant due to diminished curvature effect mixing may not be an issue for high aspect-ratio cooling channels.

  20. Micro-Cogeneration Incl. The Conversion of Chemical Energy of Biomass to Electric Energy and the Low Potential Heat

    NASA Astrophysics Data System (ADS)

    Huzvar, Jozef; Kapjor, Andrej

    2011-06-01

    This article deals with combined production of heat and electricity for small premises, such as households, where energy consumption is around few kilowatts. This proposal of micro co-generation unit uses as a heat source an automatic burner for combustion of wood pellets. Construction of an equipment for the heat transport can be designed using different basic ways of heat transfer. Electricity is produced by the two-stroke steam engine and the generator.

  1. Combustion and Heat Transfer Studies Utilizing Advanced Diagnostics: Combustion Studies

    DTIC Science & Technology

    1992-11-01

    Appendices D, E, and F). The two main modeling approaches that enabled the calculation of stability from thermochemistry considera- tions are those of...Parallel TEACH -1Te Code Using an Approximately Implicit Algorithm." Proc. Tie prime authors of this report (G. Sturgess, D. Ballal S"ym Recem Advances and

  2. Comparison of advanced battery technologies for electric vehicles

    SciTech Connect

    Dickinson, B.E.; Lalk, T.R.; Swan, D.H.

    1993-12-31

    Battery technologies of different chemistries, manufacture and geometry were evaluated as candidates for use in Electric Vehicles (EV). The candidate batteries that were evaluated include four single cell and seven multi-cell modules representing four technologies: Lead-Acid, Nickel-Cadmium, Nickel-Metal Hydride and Zinc-Bromide. A standard set of testing procedures for electric vehicle batteries, based on industry accepted testing procedures, and any tests which were specific to individual battery types were used in the evaluations. The batteries were evaluated by conducting performance tests, and by subjecting them to cyclical loading, using a computer controlled charge--discharge cycler, to simulate typical EV driving cycles. Criteria for comparison of batteries were: performance, projected vehicle range, cost, and applicability to various types of EVs. The four battery technologies have individual strengths and weaknesses and each is suited to fill a particular application. None of the batteries tested can fill every EV application.

  3. Protection of Advanced Electrical Power Systems from Atmospheric Electromagnetic Hazards.

    DTIC Science & Technology

    1981-12-01

    transients on the electrical systems of aircraft with metal or composite structures. These transients will be higher than the equipment inherent hardness...following circuits and components were surveyed. (The asterisk indicates cirucits for which the impact of substituting composite structure for metal ...4) C-14 VERTICAL STABILIZER ACTUATOR This circuit model is applicable to a C-14 with a non- metallic composite toe ramp. For a metal toe ramp, the

  4. Advances in Optimizing Weather Driven Electric Power Systems.

    NASA Astrophysics Data System (ADS)

    Clack, C.; MacDonald, A. E.; Alexander, A.; Dunbar, A. D.; Xie, Y.; Wilczak, J. M.

    2014-12-01

    The importance of weather-driven renewable energies for the United States (and global) energy portfolio is growing. The main perceived problems with weather-driven renewable energies are their intermittent nature, low power density, and high costs. The National Energy with Weather System Simulator (NEWS) is a mathematical optimization tool that allows the construction of weather-driven energy sources that will work in harmony with the needs of the system. For example, it will match the electric load, reduce variability, decrease costs, and abate carbon emissions. One important test run included existing US carbon-free power sources, natural gas power when needed, and a High Voltage Direct Current power transmission network. This study shows that the costs and carbon emissions from an optimally designed national system decrease with geographic size. It shows that with achievable estimates of wind and solar generation costs, that the US could decrease its carbon emissions by up to 80% by the early 2030s, without an increase in electric costs. The key requirement would be a 48 state network of HVDC transmission, creating a national market for electricity not possible in the current AC grid. These results were found without the need for storage. Further, we tested the effect of changing natural gas fuel prices on the optimal configuration of the national electric power system. Another test that was carried out was an extension to global regions. The extension study shows that the same properties found in the US study extend to the most populous regions of the planet. The extra test is a simplified version of the US study, and is where much more research can be carried out. We compare our results to other model results.

  5. Molten Glass for Thermal Storage: Advanced Molten Glass for Heat Transfer and Thermal Energy Storage

    SciTech Connect

    2012-01-01

    HEATS Project: Halotechnics is developing a high-temperature thermal energy storage system using a new thermal-storage and heat-transfer material: earth-abundant and low-melting-point molten glass. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night—when the sun is not out—to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. Halotechnics new thermal storage material targets a price that is potentially cheaper than the molten salt used in most commercial solar thermal storage systems today. It is also extremely stable at temperatures up to 1200°C—hundreds of degrees hotter than the highest temperature molten salt can handle. Being able to function at high temperatures will significantly increase the efficiency of turning heat into electricity. Halotechnics is developing a scalable system to pump, heat, store, and discharge the molten glass. The company is leveraging technology used in the modern glass industry, which has decades of experience handling molten glass.

  6. Recent Advances in Electrical Resistance Preheating of Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed Mahmoud; Kvande, Halvor

    2017-02-01

    There are two mainpreheating methods that are used nowadays for aluminum reduction cells. One is based on electrical resistance preheating with a thin bed of small coke and/or graphite particles between the anodes and the cathode carbon blocks. The other is flame preheating, where two or more gas or oil burners are used. Electrical resistance preheating is the oldest method, but is still frequently used by different aluminum producers. Many improvements have been made to this method by different companies over the last decade. In this paper, important points pertaining to the preparation and preheating of these cells, as well as measurements made during the preheating process and evaluation of the performance of the preheating, are illustrated. The preheating times of these cells were found to be between 36 h and 96 h for cell currents between 176 kA and 406 kA, while the resistance bed thickness was between 13 mm and 60 mm. The average cathode surface temperature at the end of the preheating was usually between 800°C and 950°C. The effect of the preheating methods on cell life is unclear and no quantifiable conclusions can be drawn. Some works carried out in the mathematical modeling area are also discussed. It is concluded that there is a need for more studies with real situations for preheated cells on the basis of actual measurements. The expected development in electrical resistance preheating of aluminum reduction cells is also summarized.

  7. Recent Advances in Electrical Resistance Preheating of Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed Mahmoud; Kvande, Halvor

    2016-06-01

    ABSTRACT There are two mainpreheating methods that are used nowadays for aluminum reduction cells. One is based on electrical resistance preheating with a thin bed of small coke and/or graphite particles between the anodes and the cathode carbon blocks. The other is flame preheating, where two or more gas or oil burners are used. Electrical resistance preheating is the oldest method, but is still frequently used by different aluminum producers. Many improvements have been made to this method by different companies over the last decade. In this paper, important points pertaining to the preparation and preheating of these cells, as well as measurements made during the preheating process and evaluation of the performance of the preheating, are illustrated. The preheating times of these cells were found to be between 36 h and 96 h for cell currents between 176 kA and 406 kA, while the resistance bed thickness was between 13 mm and 60 mm. The average cathode surface temperature at the end of the preheating was usually between 800°C and 950°C. The effect of the preheating methods on cell life is unclear and no quantifiable conclusions can be drawn. Some works carried out in the mathematical modeling area are also discussed. It is concluded that there is a need for more studies with real situations for preheated cells on the basis of actual measurements. The expected development in electrical resistance preheating of aluminum reduction cells is also summarized.

  8. Low Temperature Heat Source Utilization Current and Advanced Technology

    SciTech Connect

    Anderson, James H. Jr.; Dambly, Benjamin W.

    1992-06-01

    Once a geothermal heat source has been identified as having the potential for development, and its thermal, physical, and chemical characteristics have been determined, a method of utilization must be decided upon. This compendium will touch upon some of these concerns, and hopefully will provide the reader with a better understanding of technologies being developed that will be applicable to geothermal development in East Africa, as well as other parts of the world. The appendices contain detailed reports on Down-the-Well Turbo Pump, The Vapor-Turbine Cycle for Geothermal Power Generation, Heat Exchanger Design for Geothermal Power Plants, and a Feasibility Study of Combined Power and Water Desalting Plant Using Hot Geothermal Water. [DJE-2005

  9. New latent heat storage system with nanoparticles for thermal management of electric vehicles

    NASA Astrophysics Data System (ADS)

    Javani, N.; Dincer, I.; Naterer, G. F.

    2014-12-01

    In this paper, a new passive thermal management system for electric vehicles is developed. A latent heat thermal energy storage with nanoparticles is designed and optimized. A genetic algorithm method is employed to minimize the length of the heat exchanger tubes. The results show that even the optimum length of a shell and tube heat exchanger becomes too large to be employed in a vehicle. This is mainly due to the very low thermal conductivity of phase change material (PCM) which fills the shell side of the heat exchanger. A carbon nanotube (CNT) and PCM mixture is then studied where the probability of nanotubes in a series configuration is defined as a deterministic design parameter. Various heat transfer rates, ranging from 300 W to 600 W, are utilized to optimize battery cooling options in the heat exchanger. The optimization results show that smaller tube diameters minimize the heat exchanger length. Furthermore, finned tubes lead to a higher heat exchanger length due to more heat transfer resistance. By increasing the CNT concentration, the optimum length of the heat exchanger decreases and makes the improved thermal management system a more efficient and competitive with air and liquid thermal management systems.

  10. Advanced k-epsilon modeling of heat transfer

    NASA Technical Reports Server (NTRS)

    Kwon, Okey; Ames, Forrest E.

    1995-01-01

    This report describes two approaches to low Reynolds-number k-epsilon turbulence modeling which formulate the eddy viscosity on the wall-normal component of turbulence and a length scale. The wall-normal component of turbulence is computed via integration of the energy spectrum based on the local dissipation rate and is bounded by the isotropic condition. The models account for the anisotropy of the dissipation and the reduced mixing length due to the high strain rates present in the near-wall region. The turbulent kinetic energy and its dissipation rate were computed from the k and epsilon transport equations of Durbin. The models were tested for a wide range of turbulent flows and proved to be superior to other k-epsilon models, especially for nonequilibrium anisotropic flows. For the prediction of airfoil heat transfer, the models included a set of empirical correlations for predicting laminar-turbulent transition and laminar heat transfer augmentation due to the presence of freestream turbulence. The predictions of surface heat transfer were generally satisfactory.

  11. Proceedings of the 1987 coatings for advanced heat engines workshop

    SciTech Connect

    Not Available

    1987-01-01

    This Workshop was conducted to enhance communication among those involved in coating development for improved heat engine performance and durability. We were fortunate to have Bill Goward review the steady progress and problems encountered along the way in the use of thermal barrier coatings (TBC) in aircraft gas turbine engines. Navy contractors discussed their work toward the elusive goal of qualifying TBC for turbine airfoil applications. In the diesel community, Caterpillar and Cummins are developing TBC for combustion chamber components as part of the low heat rejection diesel engine concept. The diesel engine TBC work is based on gas turbine technology with a goal of more than twice the thickness used on gas turbine engine components. Adoption of TBC in production for diesel engines could justify a new generation of plasma spray coating equipment. Increasing interests in tribology were evident in this Workshop. Coatings have a significant role in reducing friction and wear under greater mechanical loadings at higher temperatures. The emergence of a high temperature synthetic lubricant could have an enormous impact on diesel engine design and operating conditions. The proven coating processes such as plasma spray, electron-beam physical vapor deposition, sputtering, and chemical vapor deposition have shown enhanced capabilities, particularly with microprocessor controls. Also, the newer coating schemes such as ion implantation and cathodic arc are demonstrating intriguing potential for engine applications. Coatings will play an expanding role in higher efficiency, more durable heat engines.

  12. Circulation in the high-latitude thermosphere due to electric fields and Joule heating

    NASA Technical Reports Server (NTRS)

    Heaps, M. G.; Megill, L. R.

    1975-01-01

    Electric fields in the earth's upper atmosphere are capable of setting the neutral atmosphere in motion via ion-neutral collisions as well as pressure gradients from resultant Joule heating. By means of simple models for the high-latitude thermosphere and electric fields a simplified set of coupled equations is solved which show that moderate electric fields, when present for a period of several hours, are capable of displacing the neutral atmosphere of the order of 50 km in the vertical, a few hundred kilometers in the north-south direction and over 1000 km in the east-west direction.

  13. Heating the sun's lower transition region with fine-scale electric currents

    NASA Technical Reports Server (NTRS)

    Rabin, D.; Moore, R.

    1984-01-01

    Analytical and observational data are presented to show that the lower transition zone, a 100 km thick region at 10,000-200,000 K between the solar chromosphere and corona, is heated by local electric currents. The study was spurred by correlations between the enhanced atmospheric heating and magnetospheric flux in the chromospheric network and active regions. Field aligned current heated flux loops are asserted to mainly reside in and make up most of the transition region. It is shown that thermal conduction from the sides of hot gas columns generated by the current dissipation is the source of the observed temperature distribution in the transition regions.

  14. Electrical performances of pyroelectric bimetallic strip heat engines describing a Stirling cycle

    NASA Astrophysics Data System (ADS)

    Arnaud, A.; Boughaleb, J.; Monfray, S.; Boeuf, F.; Cugat, O.; Skotnicki, T.

    2015-12-01

    This paper deals with the analytical modeling of pyroelectric bimetallic strip heat engines. These devices are designed to exploit the snap-through of a thermo-mechanically bistable membrane to transform a part of the heat flowing through the membrane into mechanical energy and to convert it into electric energy by means of a piezoelectric layer deposited on the surface of the bistable membrane. In this paper, we describe the properties of these heat engines in the case when they complete a Stirling cycle, and we evaluate the performances (available energy, Carnot efficiency...) of these harvesters at the macro- and micro-scale.

  15. High performance heat curing copper-silver powders filled electrically conductive adhesives

    NASA Astrophysics Data System (ADS)

    Cui, Hui-Wang; Jiu, Jin-Ting; Sugahara, Tohru; Nagao, Shijo; Suganuma, Katsuaki; Uchida, Hiroshi

    2015-03-01

    In this study, high performance electrically conductive adhesives were fabricated from a vinyl ester resin, a thermal initiator, silver coated copper powders, and pure silver powders, without using any other coupling agent, dispersing agent, and reducing agent. The heat cured copper-silver powders filled electrically conductive adhesives presented low bulk resistivity (e.g., 4.53 × 10-5 Ω·cm) due to the silver powders that had given high electrical conductivity to the adhesives, and high shear strength (e.g., 16.22 MPa) provided by the crosslinked structures of vinyl ester resin. These high performance copper-silver powders filled electrically conductive adhesives have lower cost than those filled by pure silver powders, which can be well used in the electronic packaging and can enlarge the application prospects of electrically conductive adhesives. [Figure not available: see fulltext.

  16. Electrical heating of soils using high efficiency electrode patterns and power phases

    DOEpatents

    Buettner, Harley M.

    1999-01-01

    Powerline-frequency electrical (joule) heating of soils using a high efficiency electrode configuration and power phase arrangement. The electrode configuration consists of several heating or current injection electrodes around the periphery of a volume of soil to be heated, all electrodes being connected to one phase of a multi-phase or a single-phase power system, and a return or extraction electrode or electrodes located inside the volume to be heated being connected to the remaining phases of the multi-phase power system or to the neutral side of the single-phase power source. This electrode configuration and power phase arrangement can be utilized anywhere where powerline frequency soil heating is applicable and thus has many potential uses including removal of volatile organic compounds such as gasoline and tricholorethylene (TCE) from contaminated areas.

  17. Design of an advanced absorption heat pump for minimum payback period

    NASA Astrophysics Data System (ADS)

    Patterson, M. R.; Perez-Blanco, H.

    1985-11-01

    Absorption heat pumps of the type analyzed here provide process heat from waste heat. A simulation model with optimization capability is now operational for an advanced sodium hydroxide-water absorption heat pump with a regenerative loop. In this type of heat pump, increasing the area of the heat exchangers increases the dollar value of the process heat output, but it also increases the capital cost. The designer is then faced with the decision of how to allocate the heat exchanger area among the several heat pump components for optimal economic benefits. The optimization feature of the program allows the user to minimize the payback period for recovery of the capital investment in the heat pump. The computer program employs proprietary software for the optimization. The program is relatively short, about 400 lines of FORTRAN, and can readily be used with different optimization subroutines if desired. Results from the model indicate that the payback period is short, about 1 to 2 years for the standard case. These predictions make this regenerative-loop heat pump an attractive cycle for further investigation.

  18. Applicability of advanced automotive heat engines to solar thermal power

    NASA Technical Reports Server (NTRS)

    Beremand, D. G.; Evans, D. G.; Alger, D. L.

    1981-01-01

    The requirements of a solar thermal power system are reviewed and compared with the predicted characteristics of automobile engines under development. A good match is found in terms of power level and efficiency when the automobile engines, designed for maximum powers of 65-100 kW (87 to 133 hp) are operated to the nominal 20-40 kW electric output requirement of the solar thermal application. At these reduced power levels it appears that the automotive gas turbine and Stirling engines have the potential to deliver the 40+ percent efficiency goal of the solar thermal program.

  19. Thermal evaluation of advanced solar dynamic heat receiver performance

    NASA Technical Reports Server (NTRS)

    Crane, Roger A.

    1989-01-01

    The thermal performance of a variety of concepts for thermal energy storage as applied to solar dynamic applications is discussed. It is recognized that designs providing large thermal gradients or large temperature swings during orbit are susceptible to early mechanical failure. Concepts incorporating heat pipe technology may encounter operational limitations over sufficiently large ranges. By reviewing the thermal performance of basic designs, the relative merits of the basic concepts are compared. In addition the effect of thermal enhancement and metal utilization as applied to each design provides a partial characterization of the performance improvements to be achieved by developing these technologies.

  20. Advanced Hall Electric Propulsion for Future In-space Transportation

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; Sankovic, John M.

    2001-01-01

    The Hall thruster is an electric propulsion device used for multiple in-space applications including orbit raising, on-orbit maneuvers, and de-orbit functions. These in-space propulsion functions are currently performed by toxic hydrazine monopropellant or hydrazine derivative/nitrogen tetroxide bi-propellant thrusters. The Hall thruster operates nominally in the 1500 sec specific impulse regime. It provides greater thrust to power than conventional gridded ion engines, thus reducing trip times and operational life when compared to that technology in Earth orbit applications. The technology in the far term, by adding a second acceleration stage, has shown promise of providing over 4000s Isp, the regime of the gridded ion engine and necessary for deep space applications. The Hall thruster system consists of three parts, the thruster, the power processor, and the propellant system. The technology is operational and commercially available at the 1.5 kW power level and 5 kW application is underway. NASA is looking toward 10 kW and eventually 50 kW-class engines for ambitious space transportation applications. The former allows launch vehicle step-down for GEO missions and demanding planetary missions such as Europa Lander, while the latter allows quick all-electric propulsion LEO to GEO transfers and non-nuclear transportation human Mars missions.

  1. Advanced radiator concepts utilizing honeycomb panel heat pipes

    NASA Technical Reports Server (NTRS)

    Fleischman, G. L.; Peck, S. J.; Tanzer, H. J.

    1987-01-01

    The feasibility of fabricating and processing moderate temperature range vapor chamber type heat pipes in a low mass honeycomb panel configuration for highly efficient radiator fins for potential use on the space station was investigated. A variety of honeycomb panel facesheet and core-ribbon wick concepts were evaluated within constraints dictated by existing manufacturing technology and equipment. Concepts evaluated include type of material, material and panel thickness, wick type and manufacturability, liquid and vapor communication among honeycomb cells, and liquid flow return from condenser to evaporator facesheet areas. A thin-wall all-welded stainless steel design with methanol as the working fluid was the initial prototype unit. It was found that an aluminum panel could not be fabricated in the same manner as a stainless steel panel due to diffusion bonding and resistance welding considerations. Therefore, a formed and welded design was developed. The prototype consists of ten panels welded together into a large panel 122 by 24 by 0.15 in., with a heat rejection capability of 1000 watts and a fin efficiency of essentially 1.0.

  2. Heat engine and electric motor torque distribution strategy for a hybrid electric vehicle

    DOEpatents

    Boberg, Evan S.; Gebby, Brian P.

    1999-09-28

    A method is provided for controlling a power train system for a hybrid electric vehicle. The method includes a torque distribution strategy for controlling the engine and the electric motor. The engine and motor commands are determined based upon the accelerator position, the battery state of charge and the amount of engine and motor torque available. The amount of torque requested for the engine is restricted by a limited rate of rise in order to reduce the emissions from the engine. The limited engine torque is supplemented by motor torque in order to meet a torque request determined based upon the accelerator position.

  3. Hot embossing of electrophoresis microchannels in PMMA substrates using electric heating wires.

    PubMed

    Gan, Zhibing; Yu, Zhengyin; Chen, Zhi; Chen, Gang

    2010-04-01

    A simple method based on electric heating wires has been developed for the rapid fabrication of poly(methyl methacrylate) (PMMA) electrophoresis microchips in ordinary laboratories without the need for microfabrication facilities. A piece of stretched electric heating wire placed across the length of a PMMA plate along its midline was sandwiched between two microscope slides under pressure. Subsequently, alternating current was allowed to pass through the wire to generate heat to emboss a separation microchannel on the PMMA separation channel plate at room temperature. The injection channel was fabricated using the same procedure on a PMMA sheet that was perpendicular to the separation channel. The complete microchip was obtained by bonding the separation channel plate to the injection channel sheet, sealing the channels inside. The electric heating wires used in this work not only generated heat; they also served as templates for embossing the microchannels. The prepared microfluidic microchips have been successfully employed in the electrophoresis separation and detection of ions in connection with contactless conductivity detection.

  4. Heat production in the windings of the stators of electric machines under stationary condition

    NASA Astrophysics Data System (ADS)

    Alebouyeh Samami, Behzad; Pieper, Martin; Breitbach, Gerd; Hodapp, Josef

    2014-12-01

    In electric machines due to high currents and resistive losses (joule heating) heat is produced. To avoid damages by overheating the design of effective cooling systems is required. Therefore the knowledge of heat sources and heat transfer processes is necessary. The purpose of this paper is to illustrate a good and effective calculation method for the temperature analysis based on homogenization techniques. These methods have been applied for the stator windings in a slot of an electric machine consisting of copper wires and resin. The key quantity here is an effective thermal conductivity, which characterizes the heterogeneous wire resin-arrangement inside the stator slot. To illustrate the applicability of the method, the analysis of a simplified, homogenized model is compared with the detailed analysis of temperature behavior inside a slot of an electric machine according to the heat generation. We considered here only the stationary situation. The achieved numerical results are accurate and show that the applied homogenization technique works in practice. Finally the results of simulations for the two cases, the original model of the slot and the homogenized model chosen for the slot (unit cell), are compared to experimental results.

  5. Advanced Redox Flow Batteries for Stationary Electrical Energy Storage

    SciTech Connect

    Li, Liyu; Kim, Soowhan; Xia, Guanguang; Wang, Wei; Yang, Zhenguo

    2012-03-19

    This report describes the status of the advanced redox flow battery research being performed at Pacific Northwest National Laboratories for the U.S. Department of Energy’s Energy Storage Systems Program. The Quarter 1 of FY2012 Milestone was completed on time. The milestone entails completion of evaluation and optimization of single cell components for the two advanced redox flow battery electrolyte chemistries recently developed at the lab, the all vanadium (V) mixed acid and V-Fe mixed acid solutions. All the single cell components to be used in future kW-scale stacks have been identified and optimized in this quarter, which include solution electrolyte, membrane or separator; carbon felt electrode and bi-polar plate. Varied electrochemical, chemical and physical evaluations were carried out to assist the component screening and optimization. The mechanisms of the battery capacity fading behavior for the all vanadium redox flow and the Fe/V battery were discovered, which allowed us to optimize the related cell operation parameters and continuously operate the system for more than three months without any capacity decay.

  6. Advanced batteries for electric vehicle applications: Nontechnical summary

    NASA Astrophysics Data System (ADS)

    Henriksen, G. L.

    This paper provides an overview of the performance characteristics of the most prominent batteries under development for electric vehicles (EV's) and compares these characteristics to the USABC Mid-Term and Long-Term criteria, as well as to typical vehicle-related battery requirements. Most of the battery performance information was obtained from independent tests, conducted using simulated driving power profiles, for DOE and EPRI at Argonne National Laboratory. The EV batteries are categorized as near-term, mid-term, and long-term technologies based on their relative development status, as well as our estimate of their potential availability as commercial EV batteries. Also, the performance capabilities generally increase in going from the near-term to the mid-term and on to the long-term technologies. To date, the USABC has chosen to fund a few selected mid-term and long-term battery technologies.

  7. Electric power processing, distribution and control for advanced aerospace vehicles.

    NASA Technical Reports Server (NTRS)

    Krausz, A.; Felch, J. L.

    1972-01-01

    The results of a current study program to develop a rational basis for selection of power processing, distribution, and control configurations for future aerospace vehicles including the Space Station, Space Shuttle, and high-performance aircraft are presented. Within the constraints imposed by the characteristics of power generation subsystems and the load utilization equipment requirements, the power processing, distribution and control subsystem can be optimized by selection of the proper distribution voltage, frequency, and overload/fault protection method. It is shown that, for large space vehicles which rely on static energy conversion to provide electric power, high-voltage dc distribution (above 100 V dc) is preferable to conventional 28 V dc and 115 V ac distribution per MIL-STD-704A. High-voltage dc also has advantages over conventional constant frequency ac systems in many aircraft applications due to the elimination of speed control, wave shaping, and synchronization equipment.

  8. Initial Determinations of Ionospheric Electric Fields and Joule Heating from MAVEN Observations

    NASA Astrophysics Data System (ADS)

    Fillingim, M. O.; Fogle, A. L.; Aleryani, O.; Dunn, P.; Lillis, R. J.; McFadden, J. P.; Connerney, J. E. P.; Mahaffy, P. R.; Andersson, L.; Ergun, R.

    2015-12-01

    MAVEN provides in-situ measurements of the neutral and ion species as well as the magnetic field throughout the ionosphere of Mars. By combining these measurements, we are able to calculate both the ionospheric currents and the ionospheric conductivity. It is then straightforward to determine the electric field in the collisional ionosphere from a simplified Ohm's law. In addition, we can also estimate the amount of Joule heating in the ionosphere from j · E. Here, we show initial determinations of both ionospheric electric fields and Joule heating using MAVEN data. The electric fields are highly variable from orbit-to-orbit suggesting that the ionospheric electrodynamics can change on timescales of several hours. These changes may be driven by changes in the upstream solar wind and IMF or may result from dynamical variations of thermospheric neutral winds.

  9. The Effect of Solution Heat Treatment on an Advanced Nickel-Base Disk Alloy

    NASA Technical Reports Server (NTRS)

    Gayda, J.; Gabb, T. P.; Kantzos, P. T.

    2004-01-01

    Five heat treat options for an advanced nickel-base disk alloy, LSHR, have been investigated. These included two conventional solution heat treat cycles, subsolvus/oil quench and supersolvus/fan cool, which yield fine grain and coarse grain microstructure disks respectively, as well as three advanced dual microstructure heat treat (DMHT) options. The DMHT options produce disks with a fine grain bore and a coarse grain rim. Based on an overall evaluation of the mechanical property data, it was evident that the three DMHT options achieved a desirable balance of properties in comparison to the conventional solution heat treatments for the LSHR alloy. However, one of the DMHT options, SUB/DMHT, produced the best set of properties, largely based on dwell crack growth data. Further evaluation of the SUB/DMHT option in spin pit experiments on a generic disk shape demonstrated the advantages and reliability of a dual grain structure at the component level.

  10. Advancement of Double Effect Absorption Cycle by Input of Low Temperature Waste Heat

    NASA Astrophysics Data System (ADS)

    Kojima, Hiroshi; Edera, Masaru; Nakamura, Makoto; Oka, Masahiro; Akisawa, Atsushi; Kashiwagi, Takao

    Energy conservation is becoming important for global environmental protection. New simple techniques of more efficient1y using the waste heat of gas co-generation systems for refrigerationare required. In first report, a new method of using the low temperature waste heat for refrigeration was proposed, and the basic characteristics of the promising methods of recovering waste heat were c1arified. In this report, the more detailed simulation model of the series flow type double effect absorption refrigerator with auxiliary heat exchanger was constructed and the static characteristics were investigated. Then experiments on this advanced absorption refrigerator were carried out, and the results of the calculation and experiments were compared and discussed. Moreover, the betterment of the simulation model of this advanced absorption refrigerator was carried out.

  11. Solid fossil-fuel recovery by electrical induction heating in situ - A proposal

    NASA Astrophysics Data System (ADS)

    Fisher, S.

    1980-04-01

    A technique, termed electrical induction heating, is proposed for in situ processes of energy production from solid fossil fuels, such as bitumen production from underground distillation of oil sand; oil by underground distillation of oil shale; petroleum from heavy oil by underground mobilization of heavy oil, from either residues of conventional liquid petroleum deposits or new deposits of viscous oil; methane and coal tar from lignite and coal deposits by underground distillation of coal; and generation of electricity by surface combustion of low calorific-value gas from underground coke gasification by combustion of the organic residue left from the underground distillation of coal by induction heating. A method of surface distillation of mined coking coal by induction heating to produce coke, methane, and coal tar is also proposed.

  12. Heat Shock Proteins in Dermatophytes: Current Advances and Perspectives

    PubMed Central

    Martinez-Rossi, Nilce M.; Jacob, Tiago R.; Sanches, Pablo R.; Peres, Nalu T.A.; Lang, Elza A.S.; Martins, Maíra P.; Rossi, Antonio

    2016-01-01

    Heat shock proteins (HSPs) are proteins whose transcription responds rapidly to temperature shifts. They constitute a family of molecular chaperones, involved in the proper folding and stabilisation of proteins under physiological and adverse conditions. HSPs also assist in the protection and recovery of cells exposed to a variety of stressful conditions, including heat. The role of HSPs extends beyond chaperoning proteins, as they also participate in diverse cellular functions, such as the assembly of macromolecular complexes, protein transport and sorting, dissociation of denatured protein aggregates, cell cycle control, and programmed cell death. They are also important antigens from a variety of pathogens, are able to stimulate innate immune cells, and are implicated in acquired immunity. In fungi, HSPs have been implicated in virulence, dimorphic transition, and drug resistance. Some HSPs are potential targets for therapeutic strategies. In this review, we discuss the current understanding of HSPs in dermatophytes, which are a group of keratinophilic fungi responsible for superficial mycoses in humans and animals. Computational analyses were performed to characterise the group of proteins in these dermatophytes, as well as to assess their conservation and to identify DNA-binding domains (5′-nGAAn-3′) in the promoter regions of the hsp genes. In addition, the quantification of the transcript levels of few genes in a pacC background helped in the development of an extended model for the regulation of the expression of the hsp genes, which supports the participation of the pH-responsive transcriptional regulator PacC in this process. PMID:27226766

  13. Rapid systemic up-regulation of genes after heat-wounding and electrical stimulation

    NASA Technical Reports Server (NTRS)

    Davies, E.; Vian, A.; Vian, C.; Stankovic, B.

    1997-01-01

    When one leaf of a tomato plant is electrically-stimulated or heat-wounded, proteinase inhibitor genes are rapidly up-regulated in distant leaves. The identity of the systemic wound signal(s) is not yet known, but major candidates include hormones transmitted via the phloem or the xylem, the electrically-stimulated self-propagating electrical signal in the phloem (the action potential, AP), or the heat-wound-induced surge in hydraulic pressure in the xylem evoking a local change in membrane potential in adjacent living cells (the variation potential, VP). In order to discriminate between these signals we have adopted two approaches. The first approach involves applying stimuli that evoke known signals and determining whether these signals have similar effects on the "model" transcripts for proteinase inhibitors (pin) and calmodulin (cal). Here we show that a heat wound almost invariably evokes a VP, while an electrical stimulation occasionally evokes an AP, and both of these signals induce accumulation of transcripts encoding proteinase inhibitors. The second approach involves identifying the array of genes turned on by heat-wounding. To this end, we have constructed a subtractive library for heat-wounded tissue, isolated over 800 putatively up-regulated clones, and shown that all but two of the fifty that we have analyzed by Northern hybridization are, indeed, up-regulated. Here we show the early kinetics of up-regulation of three of these transcripts in the terminal (4th) leaf in response to heat-wounding the 3rd leaf, about 5 cm away. Even though these transcripts show somewhat different time courses of induction, with one peaking at 30 min, another at 15 min, and another at 5 min after flaming of a distant leaf, they all exhibit a similar pattern, i.e., a transient period of transcript accumulation preceding a period of transcript decrease, followed by a second period of transcript accumulation.

  14. Pluto/Kuiper Missions with Advanced Electric Propulsion and Power

    NASA Technical Reports Server (NTRS)

    Oleson, S. R.; Patterson, M. J.; Schrieber, J.; Gefert, L. P.

    2001-01-01

    In response to a request by NASA Code SD Deep Space Exploration Technology Program, NASA Glenn Research center performed a study to identify advanced technology options to perform a Pluto/Kuiper mission without depending on a 2004 Jupiter Gravity Assist, but still arriving before 2020. A concept using a direct trajectory with small, sub-kilowatt ion thrusters and Stirling radioisotope power system was shown to allow the same or smaller launch vehicle class (EELV) as the chemical 2004 baseline and allow launch in any year and arrival in the 2014 to 2020 timeframe. With the nearly constant power available from the radioisotope power source such small ion propelled spacecraft could explore many of the outer planetary targets. Such studies are already underway. Additional information is contained in the original extended abstract.

  15. Investigation of the performance of the General Electric ADVANCE positron emission tomograph in 3D mode

    SciTech Connect

    Lewellen, T.K.; Kohlmyer, S.G.; Miyaoka, R.S.; Kaplan, M.S.; Stearns, C.W.; Schubert, S.F.

    1996-08-01

    Performance measurements of the General Electric ADVANCE Positron Emission Tomograph operating with the septa retracted (3D mode) were made. All reconstructions were performed with the GE ADVANCE 3D package. Performance tests were carried out with: the NEMA phantoms; a 3D Hoffman phantom; a Data Spectrum torso phantom with lung and cardiac inserts; and the Utah 3D evaluation phantom. Data collected included: transaxial and axial resolution, uniformity, recovery coefficients, count rate performance, dead time accuracy, and effect of scatter correction.

  16. High Temperature Solid Lubricant Materials for Heavy Duty and Advanced Heat Engines

    NASA Technical Reports Server (NTRS)

    Dellacorte, C.; Wood, J. C.

    1994-01-01

    Advanced engine designs incorporate higher mechanical and thermal loading to achieve efficiency improvements. This approach often leads to higher operating temperatures of critical sliding elements (e.g. piston ring/cylinder wall contacts and valve guides) which compromise the use of conventional and even advanced synthetic liquid lubricants. For these applications solid lubricants must be considered. Several novel solid lubricant composites and coatings designated PS/PM200 have been employed to dry and marginally oil lubricated contacts in advanced heat engines. These applications include cylinder kits of heavy duty diesels, and high temperature Stirling engines, sidewall seals of rotary engines, and various exhaust valve and exhaust component applications. This paper describes the tribological and thermophysical properties of these tribomaterials and reviews the results of applying them to engine applications. Other potential tribological materials and applications are also discussed with particular emphasis on heavy duty and advanced heat engines.

  17. Electric utility acid fuel cell stack technology advancement

    NASA Technical Reports Server (NTRS)

    Congdon, J. V.; Goller, G. J.; Greising, G. J.; Obrien, J. J.; Randall, S. A.; Sandelli, G. J.; Breault, R. D.; Austin, G. W.; Bopse, S.; Coykendall, R. D.

    1984-01-01

    The principal effort under this program was directed at the fuel cell stack technology required to accomplish the initial feasibility demonstrations of increased cell stack operating pressures and temperatures, increased cell active area, incorporation of the ribbed substrate cell configuration at the bove conditions, and the introduction of higher performance electrocatalysts. The program results were successful with the primary accomplishments being: (1) fabrication of 10 sq ft ribbed substrate, cell components including higher performing electrocatalysts; (2) assembly of a 10 sq ft, 30-cell short stack; and (3) initial test of this stack at 120 psia and 405 F. These accomplishments demonstrate the feasibility of fabricating and handling large area cells using materials and processes that are oriented to low cost manufacture. An additional accomplishment under the program was the testing of two 3.7 sq ft short stacks at 12 psia/405 F to 5400 and 4500 hours respectively. These tests demonstrate the durability of the components and the cell stack configuration to a nominal 5000 hours at the higher pressure and temperature condition planned for the next electric utility power plant.

  18. Automatic control of electric thermal storage (heat) under real-time pricing. Final report

    SciTech Connect

    Daryanian, B.; Tabors, R.D.; Bohn, R.E.

    1995-01-01

    Real-time pricing (RTP) can be used by electric utilities as a control signal for responsive demand-side management (DSM) programs. Electric thermal storage (ETS) systems in buildings provide the inherent flexibility needed to take advantage of variations in prices. Under RTP, optimal performance for ETS operations is achieved under market conditions where reductions in customers` costs coincide with the lowering of the cost of service for electric utilities. The RTP signal conveys the time-varying actual marginal cost of the electric service to customers. The RTP rate is a combination of various cost components, including marginal generation fuel and maintenance costs, marginal costs of transmission and distribution losses, and marginal quality of supply and transmission costs. This report describes the results of an experiment in automatic control of heat storage systems under RTP during the winter seasons of 1989--90 and 1990--91.

  19. Advanced thermal energy management: A thermal test bed and heat pipe simulation

    NASA Technical Reports Server (NTRS)

    Barile, Ronald G.

    1986-01-01

    Work initiated on a common-module thermal test simulation was continued, and a second project on heat pipe simulation was begun. The test bed, constructed from surplus Skylab equipment, was modeled and solved for various thermal load and flow conditions. Low thermal load caused the radiator fluid, Coolanol 25, to thicken due to its temperature avoided by using a regenerator-heat-exchanger. Other possible solutions modeled include a radiator heater and shunting heat from the central thermal bus to the radiator. Also, module air temperature can become excessive with high avionics load. A second preoject concerning advanced heat pipe concepts was initiated. A program was written which calculates fluid physical properties, liquid and vapor pressure in the evaporator and condenser, fluid flow rates, and thermal flux. The program is directed to evaluating newer heat pipe wicks and geometries, especially water in an artery surrounded by six vapor channels. Effects of temperature, groove and slot dimensions, and wick properties are reported.

  20. Advanced interface heat exchangers for the Space Station main thermal bus

    NASA Technical Reports Server (NTRS)

    Valenzuela, Javier A.

    1990-01-01

    Future evolution and growth of the Space Station will place increasing demands on the thermal management system by the addition of new payloads and from increased activity in the habitat modules. To meet this need, Creare is developing advanced evaporators, condensors, and single-phase heat exchangers for operation in microgravity. The objective is to achieve a several-fold increase in the heat flux capability of these components, while operating at the same temperature difference as specified for the present interface heat exchangers. Two prototype interface heat exchangers are presently being developed: one to interface the main thermal bus to a payload two-phase ammonia bus, and the other, to interface with the crew module single-phase water loop. The results achieved to date in the development of these heat exchangers are reviewed.

  1. Experimental Investigation of Pool Boiling Heat Transfer Enhancement in Microgravity in the Presence of Electric Fields

    NASA Technical Reports Server (NTRS)

    Herman, Cila

    1996-01-01

    Boiling is an effective mode of heat transfer since high heat flux levels are possible driven by relatively small temperature differences. The high heat transfer coefficients associated with boiling have made the use of these processes increasingly attractive to aerospace engineering. Applications of this type include compact evaporators in the thermal control of aircraft avionics and spacecraft environments, heat pipes, and use of boiling to cool electronic equipment. In spite of its efficiency, cooling based on liquid-vapor phase change processes has not yet found wide application in aerospace engineering due to specific problems associated with the low gravity environment. After a heated surface has reached the superheat required for the initiation of nucleate boiling, bubbles will start forming at nucleation sites along the solid interface by evaporation of the liquid. Bubbles in contact with the wall will continue growing by this mechanism until they detach. In terrestrial conditions, bubble detachment is determined by the competition between body forces (e.g. buoyancy) and surface tension forces that act to anchor the bubble along the three phase contact line. For a given body force potential and a balance of tensions along the three phase contact line, bubbles must reach a critical size before the body force can cause them to detach from the wall. In a low gravity environment the critical bubble size for detachment is much larger than under terrestrial conditions, since buoyancy is a less effective means of bubble removal. Active techniques of heat transfer enhancement in single phase and phase change processes by utilizing electric fields have been the subject of intensive research during recent years. The field of electrohydrodynamics (EHD) deals with the interactions between electric fields, flow fields and temperature fields. Previous studies indicate that in terrestrial applications nucleate boiling heat transfer can be increased by a factor of 50 as

  2. Thermodynamics of the interconversion of heat and work via plasma electric fields

    SciTech Connect

    Avinash, K.

    2010-12-15

    Thermodynamics of a system where a group of cold charged particles locally confined in a volume V{sub P} within a warm plasma of temperature T and volume V (V{sub P}heat and mechanical work via isothermal compression/expansion of plasma electric field (associated with charged particles) in a plasma heat pump and ES heat engine cycle is demonstrated. The efficiency of the plasma heat pump is discussed in terms of its power efficiency {eta}{sub P} and is shown to be close to unity

  3. Bench Testing Results for the Electrical PCM-Assisted Thermal Heating System (ePATHS)

    SciTech Connect

    LaClair, Tim J.; Gao, Zhiming; Abdelaziz, Omar

    2016-04-20

    Bench testing of the Electrical PCM-Assisted Thermal Heating System (ePATHS) was completed at the Building Technologies Research and Integration Center (BTRIC) at the Oak Ridge National Laboratory (ORNL). The ePATHS is a thermal energy storage device designed to reduce the energy required from the battery for cabin heating of electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs). ORNL s testing of the ePATHS assessed three main aspects of operation of the device: 1.ePATHS charging evaluation: measure the time to charge and the energy input needed to fully charge the PCM for a range of different ambient conditions. 2.ePATHS Discharge Evaluations: measure the energy provided by the PCM HX, both during mode 1 and mode 2 operation, and confirm the cabin heating duration that can be provided by the ePATHS. This is the primary evaluation to validate the system performance, and an array of multiple ambient conditions and operating scenarios were tested. 3.Evaluation of Thermal Losses from the ePATHS during Cold Soak: this test will evaluate the performance of the insulation system for the ePATHS. The charged ePATHS undergoes a long-term soak in cold ambient temperature conditions, and the heat losses will be evaluated to validate that the performance meets the maximum energy loss requirement.

  4. Advanced concepts and solutions for geothermal heating applied in Oradea, Romania

    NASA Astrophysics Data System (ADS)

    Antal, C.; Popa, F.; Mos, M.; Tigan, D.; Popa, B.; Muresan, V.

    2017-01-01

    Approximately 70% of the total population of Oradea benefits from centralized heating, about 55,000 apartments and 159,000 inhabitants are connected. The heating system of Oradea consists of: sources of thermal energy production (Combined heat and power (CHP) I Oradea and geothermal water heating plants); a transport network of heat; heat distribution network for heating and domestic hot water; substations, most of them equipped with worn and obsolete equipment. Recently, only a few heat exchangers were rehabilitated and electric valves were installed to control the water flow. After heat extraction, geothermal chilled waters from the Oradea area are: discharged into the sewer system of the city, paying a fee to the local water company which manages the city’s sewers; discharged into the small river Peta; or re-injected into the reservoir. In order to ensure environmental protection and a sustainable energy development in Oradea, renewable sources of energy have been promoted in recent years. In this respect, the creation of a new well for geothermal water re-injection into the reservoir limits any accidental thermal pollution of the environment, while ensuring the conservation properties of the aquifer by recharging with geothermal chilled water. The paper presents the achievements of such a project whose aim is to replace thermal energy obtained from coal with geothermal heating. The novelty consists in the fact that within the substation we will replace old heat exchangers, circulation pumps and valves with fully automated substations operating in parallel on both a geothermal system and on a primary heating system of a thermal plant.

  5. Advanced Space Robotics and Solar Electric Propulsion: Enabling Technologies for Future Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Kaplan, M.; Tadros, A.

    2017-02-01

    Obtaining answers to questions posed by planetary scientists over the next several decades will require the ability to travel further while exploring and gathering data in more remote locations of our solar system. Timely investments need to be made in developing and demonstrating solar electric propulsion and advanced space robotics technologies.

  6. Design options for automotive batteries in advanced car electrical systems

    NASA Astrophysics Data System (ADS)

    Peters, K.

    The need to reduce fuel consumption, minimize emissions, and improve levels of safety, comfort and reliability is expected to result in a much higher demand for electric power in cars within the next 5 years. Forecasts vary, but a fourfold increase in starting power to 20 kW is possible, particularly if automatic stop/start features are adopted to significantly reduce fuel consumption and exhaust emissions. Increases in the low-rate energy demand are also forecast, but the use of larger alternators may avoid unacceptable high battery weights. It is also suggested from operational models that the battery will be cycled more deeply. In examining possible designs, the beneficial features of valve-regulated lead-acid batteries made with compressed absorbent separators are apparent. Several of their attributes are considered. They offer higher specific power, improved cycling capability and greater vibration resistance, as well as more flexibility in packaging and installation. Optional circuits considered for dual-voltage supplies are separate batteries for engine starting (36 V) and low-power duties (12 V), and a universal battery (36 V) coupled to a d.c.-d.c. converter for a 12-V equipment. Battery designs, which can be made on commercially available equipment with similar manufacturing costs (per W h and per W) to current products, are discussed. The 36-V battery, made with 0.7 mm thick plates, in the dual-battery system weighs 18.5 kg and has a cold-cranking amp (CCA) rating of 790 A at -18°C to 21.6 V (1080 W kg -1 at a mean voltage of 25.4 V). The associated, cycleable 12-V battery, provides 1.5 kW h and weighs 24.6 kg. Thus, the combined battery weight is 43.1 kg. The single universal battery, with cycling capability, weighs 45.4 kg, has a CCA rating of 810 A (441 W kg -1 at a mean voltage of 24.7 V), and when connected to the d.c.-d.c. converter at 75% efficiency provides a low-power capacity of 1.5 kW h.

  7. Electric Ground Support Equipment Advanced Battery Technology Demonstration Project at the Ontario Airport

    SciTech Connect

    Tyler Gray; Jeremy Diez; Jeffrey Wishart; James Francfort

    2013-07-01

    The intent of the electric Ground Support Equipment (eGSE) demonstration is to evaluate the day-to-day vehicle performance of electric baggage tractors using two advanced battery technologies to demonstrate possible replacements for the flooded lead-acid (FLA) batteries utilized throughout the industry. These advanced battery technologies have the potential to resolve barriers to the widespread adoption of eGSE deployment. Validation testing had not previously been performed within fleet operations to determine if the performance of current advanced batteries is sufficient to withstand the duty cycle of electric baggage tractors. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. The demonstration project also grew the relationship with Southwest Airlines (SWA), our demonstration partner at Ontario International Airport (ONT), located in Ontario, California. The results of this study have encouraged a proposal for a future demonstration project with SWA.

  8. Advanced propulsion concepts study: Comparative study of solar electric propulsion and laser electric propulsion

    NASA Technical Reports Server (NTRS)

    Forward, R. L.

    1975-01-01

    Solar electric propulsion (SEP) and laser electric propulsion (LEP) was compared. The LEP system configuration consists of an 80 kW visible laser source on earth, transmitting via an 8 m diameter adaptively controlled phased array through the atmosphere to a 4 m diameter synchronous relay mirror that tracks the LEP spacecraft. The only significant change in the SEP spacecraft for an LEP mission is the replacement of the two 3.7 m by 33.5 m solar cell arrays with a single 8 m diameter laser photovoltaic array. The solar cell array weight is decreased from 320 kg to 120 kg for an increase in payload of 200 kg and a decrease in specific mass of the power system from 20.5 kg/kW to 7.8 kg/kW.

  9. Influence of mashed potato dielectric properties and circulating water electric conductivity on radio frequency heating at 27 MHz.

    PubMed

    Wang, Jian; Olsen, Robert G; Tang, Juming; Tang, Zhongwei

    2008-01-01

    Experiments and computer simulations were conducted to systematically investigate the influence of mashed potato dielectric properties and circulating water electric conductivity on electromagnetic field distribution, heating rate, and heating pattern in packaged food during radio frequency (RF) heating processes in a 6 kW, 27 MHz laboratory scale RF heating system. Both experimental and simulation results indicated that for the selected food (mashed potato) in this study, the heating rate decreased with an increase of electric conductivity of circulating water and food salt content. Simplified analytical calculations were carried out to verify the simulation results, which further indicated that the electric field distribution in the mashed potato samples was also influenced by their dielectric properties and the electric conductivity of the surrounding circulating water. Knowing the influence of water electric conductivity and mashed potato dielectric properties on the heating rate and heating pattern is helpful in optimizing the radio frequency heating process by properly adjusting these factors. The results demonstrate that computer simulation has the ability to demonstrate influence on RF heat pattern caused by the variation of material physical properties and the potential to aid the improvement on construction and modification of RF heating systems.

  10. Heat dissipation due to ferromagnetic resonance in a ferromagnetic metal monitored by electrical resistance measurement

    SciTech Connect

    Yamanoi, Kazuto; Yokotani, Yuki; Kimura, Takashi

    2015-11-02

    The heat dissipation due to the resonant precessional motion of the magnetization in a ferromagnetic metal has been investigated. We demonstrated that the temperature during the ferromagnetic resonance can be simply detected by the electrical resistance measurement of the Cu strip line in contact with the ferromagnetic metal. The temperature change of the Cu strip due to the ferromagnetic resonance was found to exceed 10 K, which significantly affects the spin-current transport. The influence of the thermal conductivity of the substrate on the heating was also investigated.

  11. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Klaus, Kurt K.; Elsperman, M. S.; Rogers, F.

    2013-10-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  12. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Elsperman, M. S.; Klaus, K.; Rogers, F.

    2013-12-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  13. An advanced electric propulsion diagnostic (AEPD) platform for in-situ characterization of electric propulsion thrusters and ion beam sources

    NASA Astrophysics Data System (ADS)

    Bundesmann, Carsten; Eichhorn, Christoph; Scholze, Frank; Spemann, Daniel; Neumann, Horst; Pagano, Damiano; Scaranzin, Simone; Scortecci, Fabrizio; Leiter, Hans J.; Gauter, Sven; Wiese, Ruben; Kersten, Holger; Holste, Kristof; Köhler, Peter; Klar, Peter J.; Mazouffre, Stéphane; Blott, Richard; Bulit, Alexandra; Dannenmayer, Käthe

    2016-10-01

    Experimental characterization is an essential task in development, qualification and optimization process of electric propulsion thrusters or ion beam sources for material processing, because it can verify that the thruster or ion beam source fulfills the requested mission or application requirements, and it can provide parameters for thruster and plasma modeling. Moreover, there is a need for standardizing electric propulsion thruster diagnostics in order to make characterization results of different thrusters and also from measurements performed in different vacuum facilities reliable and comparable. Therefore, we have developed an advanced electric propulsion diagnostic (AEPD) platform, which allows a comprehensive in-situ characterization of electric propulsion thrusters (or ion beam sources) and could serve as a standard on-ground tool in the future. The AEPD platform uses a five-axis positioning system and provides the option to use diagnostic tools for beam characterization (Faraday probe, retarding potential analyzer, ExB probe, active thermal probe), for optical inspection (telemicroscope, triangular laser head), and for thermal characterization (pyrometer, thermocamera). Here we describe the capabilities of the diagnostic platform and provide first experimental results of the characterization of a gridded ion thruster RIT- μX.

  14. Assessment of impact of advanced energy transmission fluids on district heating and cooling systems (Phase 1)

    SciTech Connect

    Kasza, K.E.; Chen, M.M.

    1987-09-01

    Argonne National Laboratory (ANL), under sponsorship of the US Department of Energy (DOE) Office of Buildings and Community Systems, has embarked upon a comprehensive, long-range program to develop high-performance advanced energy transmission fluids for use in district heating and cooling (DHC) systems. ANL has the lead technical role in this DOE program. These advanced fluids will substantially reduce flow frictional losses and enhance energy transfer. In system enhancement scoping studies conducted by ANL, the fluids yielded potentially significant upfront capital equipment cost reductions by allowing the use of smaller pipes, pumps, heat exchangers, and storage tanks as well as reductions in operational costs. This report presents the first-phase results of assessment of impact of the advanced fluids on DHC systems. Future reports will focus on assessment of impact on hardware performance, capital eqiupment, and operation costs. 9 refs., 30 figs., 2 tab.

  15. Waste Heat Recovery from the Advanced Test Reactor Secondary Coolant Loop

    SciTech Connect

    Donna Post Guillen

    2012-11-01

    This study investigated the feasibility of using a waste heat recovery system (WHRS) to recover heat from the Advanced Test Reactor (ATR) secondary coolant system (SCS). This heat would be used to preheat air for space heating of the reactor building, thus reducing energy consumption, carbon footprint, and energy costs. Currently, the waste heat from the reactor is rejected to the atmosphere via a four-cell, induced-draft cooling tower. Potential energy and cost savings are 929 kW and $285K/yr. The WHRS would extract a tertiary coolant stream from the SCS loop and pump it to a new plate and frame heat exchanger, from which the heat would be transferred to a glycol loop for preheating outdoor air supplied to the heating and ventilation system. The use of glycol was proposed to avoid the freezing issues that plagued and ultimately caused the failure of a WHRS installed at the ATR in the 1980s. This study assessed the potential installation of a new WHRS for technical, logistical, and economic feasibility.

  16. Photo-chemical response of the night-time mesosphere to electric field heating

    NASA Astrophysics Data System (ADS)

    Kotovsky, D. A.; Moore, R. C.

    2015-12-01

    A zero-dimensional, photo-chemical model of the night-time mesosphere based upon the Mitra-Rowe scheme [Rowe et al., 1974] has been developed to examine the time dynamics of electron density changes produced by high-intensity, electric field heating. Additional negative- and positive-ion processes necessary to account for high electron temperatures (order of eV) have been included. Results of the model are compared to the time dynamics of lightning produced, early VLF scattering events. Among other results, we discuss co-operative mechanisms which lead to slow enhancements of electron densities (up to a few seconds) proceeding a single, shorter duration electric field heating pulse. Such mechanisms are capable of explaining all observations of early/slow VLF scattering events to date, including those associated with only a single observed radio atmospheric.

  17. Electric Drive Dynamic Thermal System Model for Advanced Vehicle Propulsion Technologies: Cooperative Research and Development Final Report, CRADA Number CRD-09-360

    SciTech Connect

    Bennion, K.

    2013-10-01

    Electric drive systems, which include electric machines and power electronics, are a key enabling technology for advanced vehicle propulsion systems that reduce the dependence of the U.S. transportation sector on petroleum. However, to penetrate the market, these electric drive technologies must enable vehicle solutions that are economically viable. The push to make critical electric drivesystems smaller, lighter, and more cost-effective brings respective challenges associated with heat removal and system efficiency. In addition, the wide application of electric drive systems to alternative propulsion technologies ranging from integrated starter generators, to hybrid electric vehicles, to full electric vehicles presents challenges in terms of sizing critical components andthermal management systems over a range of in-use operating conditions. This effort focused on developing a modular modeling methodology to enable multi-scale and multi-physics simulation capabilities leading to generic electric drive system models applicable to alternative vehicle propulsion configurations. The primary benefit for the National Renewable Energy Laboratory (NREL) is the abilityto define operating losses with the respective impact on component sizing, temperature, and thermal management at the component, subsystem, and system level. However, the flexible nature of the model also allows other uses related to evaluating the impacts of alternative component designs or control schemes depending on the interests of other parties.

  18. Development of Novel Alternative Technologies for Decontamination of Warfare Agents: Electric Heating with Intrinsically Conductive Polymers

    DTIC Science & Technology

    2007-11-02

    processibility [9,10]. In this work, dodecylbenzene sulfonic acid (DBSA) doped polyaniline (PANI-DBSA) was synthesized by chemical oxidative emulsion...the preparation of the PANI-DBSA solution. III-2. Polymerization Polyaniline -DBSA powder was synthesized by chemical oxidative emulsion...Joule)-heating with conducting polymers. The basic concept is that electrically conducting polymers, such as polyaniline , can be used as coatings or

  19. Resolving electrical conductivities from collisionally damped plasmons in isochorically heated warm dense aluminum

    SciTech Connect

    Sperling, P.; Fletcher, L. B.; Chung, H. -K.; Gamboa, E. J.; Lee, H. J.; Omarbakiyeva, Y.; Reinholz, H.; Ropke, G.; Rosmej, S.; Zastrau, U.; Glenzer, S. H.

    2016-03-29

    We measure the highly-resolved inelastic x-ray scattering spectrum of isochorically ultrafast heated aluminum. In the x-ray forward scattering spectra the electron temperature could be measured from the down- and upshifted plasmon, where the electron density of ne = 1:8 1023 cm3 is known a priori. We have studied the plasmon damping by applying electron-particle collision models beyond the Born approximation determining the electrical conductivity of warm dense aluminum.

  20. Impacts of Various Characteristics of Electricity and Heat Demand on the Optimal Configuration of a Microgrid

    NASA Astrophysics Data System (ADS)

    Bando, Shigeru; Watanabe, Hiroki; Asano, Hiroshi; Tsujita, Shinsuke

    A methodology was developed to design the number and capacity for each piece of equipment (e.g. gas engines, batteries, thermal storage tanks) in microgrids with combined heat and power systems. We analyzed three types of microgrids; the first one consists of an office building and an apartment, the second one consists of a hospital and an apartment, the third one consists of a hotel, office and retails. In the methodology, annual cost is minimized by considering the partial load efficiency of a gas engine and its scale economy, and the optimal number and capacity of each piece of equipment and the annual operational schedule are determined by using the optimal planning method. Based on calculations using this design methodology, it is found that the optimal number of gas engines is determined by the ratio of bottom to peak of the electricity demand and the ratio of heat to electricity demand. The optimal capacity of a battery required to supply electricity for a limited time during a peak demand period is auxiliary. The thermal storage tank for space cooling and space heating is selected to minimize the use of auxiliary equipment such as a gas absorption chiller.

  1. Dynamic thermal characteristics of heat pipe via segmented thermal resistance model for electric vehicle battery cooling

    NASA Astrophysics Data System (ADS)

    Liu, Feifei; Lan, Fengchong; Chen, Jiqing

    2016-07-01

    Heat pipe cooling for battery thermal management systems (BTMSs) in electric vehicles (EVs) is growing due to its advantages of high cooling efficiency, compact structure and flexible geometry. Considering the transient conduction, phase change and uncertain thermal conditions in a heat pipe, it is challenging to obtain the dynamic thermal characteristics accurately in such complex heat and mass transfer process. In this paper, a ;segmented; thermal resistance model of a heat pipe is proposed based on thermal circuit method. The equivalent conductivities of different segments, viz. the evaporator and condenser of pipe, are used to determine their own thermal parameters and conditions integrated into the thermal model of battery for a complete three-dimensional (3D) computational fluid dynamics (CFD) simulation. The proposed ;segmented; model shows more precise than the ;non-segmented; model by the comparison of simulated and experimental temperature distribution and variation of an ultra-thin micro heat pipe (UMHP) battery pack, and has less calculation error to obtain dynamic thermal behavior for exact thermal design, management and control of heat pipe BTMSs. Using the ;segmented; model, the cooling effect of the UMHP pack with different natural/forced convection and arrangements is predicted, and the results correspond well to the tests.

  2. Comparison of Advanced Residential Water Heating Technologies in the United States

    SciTech Connect

    Maguire, Jeff; Fang, Xia; Wilson, Eric

    2013-05-01

    In this study, gas storage, gas tankless, condensing, electric storage, heat pump, and solar water heaters were simulated in several different climates across the United States, installed in both conditioned and unconditioned space and subjected to several different draw profiles. While many pre-existing models were used, new models of condensing and heat pump water heaters were created specifically for this work. In each case modeled, the whole house was simulated along with the water heater to capture any interactions between the water heater and the space conditioning equipment.

  3. Development of portable measuring system for testing of electrical vehicle's heat energy recovery system

    NASA Astrophysics Data System (ADS)

    Sarvajcz, K.; Váradiné Szarka, A.

    2016-11-01

    Nowadays the consumer society applies a huge amount of energy in many fields including transportation sector. Internal combustion vehicles contribute substantially to the air pollution. An alternative solution for reducing energy consumption is replacing the internal combustion vehicles by electrical or hybrid vehicles. Today one of the biggest disadvantages of the electrical vehicles is the finite capacity of batteries. The research topic presented in this paper is the „Energy Harvesting”, and development of energy recovery system for electrical vehicles which largely contributes in increasing the driving range. At the current phase of the research efficiency analysis of the heat energy recovery devices are investigated in real driving circumstances. Computer based mobile and wireless measurement system for the analysis was developed, tested and installed in a real vehicle. Driving tests were performed and analysed in different circumstances.

  4. On the correlation of electrical conductivity and heat flow in Middle Valley, Juan de Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Webb, Spahr C.; Edwards, R. Nigel

    1995-11-01

    The near-surface electrical conductivity has been mapped within an area of Middle Valley, a sediment-filled axial valley at the northern end of the Juan de Fuca ridge. The conductivity in the uppermost 20 m of sediment was determined by analyzing the magnetic field signal transmitted between a source coil and a receiver that were towed along the seafloor. The instrument is a version of a time domain electromagnetic (TDEM) sounding system. The heat flow pattern within Middle Valley, with a large central anomaly above a basement high, is reproduced by the conductivity measurements, the result of enhanced pore fluid electrical conductivity due to higher near-surface temperatures in the high heat flow regions. The high correlation between heat flow and conductivity requires that porosity as inferred from Archie's law must be nearly uniform in the central part of the study area. Porosities derived from the conductivity measurements are in close agreement with measurements from the Ocean Drilling Project (ODP) boreholes. Higher near-surface porosities are required in the eastern part of the valley to match the observed heat flow, consistent with the higher porosity seen at ODP site 855. A small region of apparently lower porosity was detected to the west of the center of the valley.

  5. Thermal and electrical influences from bulk plasma in cathode heating modeling

    NASA Astrophysics Data System (ADS)

    Chen, Tang; Wang, Cheng; Zhang, Xiao-Ning; Zhang, Hao; Xia, Wei-Dong

    2017-02-01

    In this paper, a numerical calculation is performed for the purpose of estimating the thermal and electrical influences from bulk plasma in cathode heating modeling, in other words researching the necessity of a coupling bulk plasma in near-cathode layer modeling. The proposed model applied in the present work is an improved one from previous work. In this model, the near-cathode region is divided into two parts: the sheath and the ionization layer. The Schottky effect at the cathode surface is considered based on the analytic solution of a 1D sheath model. It is noted that the arc column is calculated simultaneously in the near-cathode region and the cathode bulk. An application is presented for an atmospheric free burning argon arc with arc currents of 50 A-600 A. The modeling results show three interesting points: (1) at the cathode surface, energy transport due to heat conduction of heavy particles and electrons is comparable to total heating flux, no matter whether the arc discharge is performed in a high (400 A) or low current (50 A) situation; (2) the electrical influence from bulk plasma on the cathode heating modeling becomes obvious in a high current situation (>400 A) for the spot mode; (3) the near-cathode layer voltage drop ({{U}\\text{tot}} ) is larger in the diffuse mode than in the spot mode for the same current, which is just the opposite to that for decoupled modeling.

  6. Investigation of austenitic alloys for advanced heat recovery and hot gas cleanup systems

    SciTech Connect

    Swindeman, R.W.; Ren, W.

    1996-06-01

    The objective of the research is to provide databases and design criteria to assist in the selection of optimum alloys for construction of components needed to contain process streams in advanced heat recovery and hot-gas cleanup systems. Typical components include: steam line piping and superheater tubing for low emission boilers (600 to 700{degrees}C), heat exchanger tubing for advanced steam cycles and topping cycle systems (650 to 800{degrees}C), foil materials for recuperators, on advanced turbine systems (700 to 750{degrees}C), and tubesheets for barrier filters, liners for piping, cyclones, and blowback system tubing for hot-gas cleanup systems (850 to 1000{degrees}C). The materials being examined fall into several classes, depending on which of the advanced heat recovery concepts is of concern. These classes include martensitic steels for service to 650{degrees}C, lean stainless steels and modified 25Cr-30Ni steels for service to 700{degrees}C, modified 25Cr-20Ni steels for service to 900{degrees}C, and high Ni-Cr-Fe or Ni-Cr-Co-Fe alloys for service to 1000{degrees}C.

  7. A Review of Recent Advances in Research on Extreme Heat Events

    NASA Technical Reports Server (NTRS)

    Horton, Radley M.; Mankin, Justin S.; Lesk, Corey; Coffel, Ethan; Raymond, Colin

    2016-01-01

    Reviewing recent literature, we report that changes in extreme heat event characteristics such as magnitude, frequency, and duration are highly sensitive to changes in mean global-scale warming. Numerous studies have detected significant changes in the observed occurrence of extreme heat events, irrespective of how such events are defined. Further, a number of these studies have attributed present-day changes in the risk of individual heat events and the documented global-scale increase in such events to anthropogenic-driven warming. Advances in process-based studies of heat events have focused on the proximate land-atmosphere interactions through soil moisture anomalies, and changes in occurrence of the underlying atmospheric circulation associated with heat events in the mid-latitudes. While evidence for a number of hypotheses remains limited, climate change nevertheless points to tail risks of possible changes in heat extremes that could exceed estimates generated from model outputs of mean temperature. We also explore risks associated with compound extreme events and nonlinear impacts associated with extreme heat.

  8. Conductive heating and microwave hydrolysis under identical heating profiles for advanced anaerobic digestion of municipal sludge.

    PubMed

    Mehdizadeh, Seyedeh Neda; Eskicioglu, Cigdem; Bobowski, Jake; Johnson, Thomas

    2013-09-15

    Microwave (2.45 GHz, 1200 W) and conventional heating (custom pressure vessel) pretreatments were applied to dewatered municipal waste sludge (18% total solids) using identical heating profiles that span a wide range of temperatures (80-160 °C). Fourteen lab-scale semi-continuous digesters were set up to optimize the energy (methane) output and sludge retention time (SRT) requirements of untreated (control) and thermally pretreated anaerobic digesters operated under mesophilic and thermophilic temperatures. Both pretreatment methods indicated that in the pretreatment range of 80-160 °C, temperature was a statistically significant factor (p-value < 0.05) for increasing solubilization of chemical oxygen demand and biopolymers (proteins, sugars, humic acids) of the waste sludge. However, the type of pretreatment method, i.e. microwave versus conventional heating, had no statistically significant effect (p-value >0.05) on sludge solubilization. With the exception of the control digesters at a 5-d SRT, all control and pretreated digesters achieved steady state at all three SRTs, corresponding to volumetric organic loading rates of 1.74-6.96 g chemical oxygen demand/L/d. At an SRT of 5 d, both mesophilic and thermophilic controls stopped producing biogas after 20 d of operation with total volatile fatty acids concentrations exceeding 1818 mg/L at pH <5.64 for mesophilic and 2853 mg/L at pH <7.02 for thermophilic controls, while the pretreated digesters continued producing biogas. Furthermore, relative (to control) organic removal efficiencies dramatically increased as SRT was shortened from 20 to 10 and then 5 d, indicating that the control digesters were challenged as the organic loading rate was increased. Energy analysis showed that, at an elevated temperature of 160 °C, the amount of methane recovered was not enough to compensate for the energy input. Among the digesters with positive net energy productions, control and pretreated digesters at 80 °C were more

  9. FY2010 Annual Progress Report for Advanced Power Electronics and Electric Motors

    SciTech Connect

    Rogers, Susan A.

    2011-01-01

    The Advanced Power Electronics and Electric Machines (APEEM) subprogram within the Vehicle Technologies Program provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE) and electric motor technologies that will leapfrog current on-the-road technologies. The research and development (R&D) is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency.

  10. FY2011 Advanced Power Electronics and Electric Motors Annual Progress Report

    SciTech Connect

    Rogers, Susan A.

    2012-01-31

    The Advanced Power Electronics and Electric Motors (APEEM) program within the DOE Vehicle Technologies Program (VTP) provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE), electric motor (EM), thermal management, and traction drive system technologies that will leapfrog current on-the-road technologies. The research and development (R&D) is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency.

  11. FY2012 Advanced Power Electronics and Electric Motors Annual Progress Report

    SciTech Connect

    Rogers, Susan A.

    2013-03-01

    The Advanced Power Electronics and Electric Motors (APEEM) program within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE), electric motor (EM), thermal management, and traction drive system technologies that will leapfrog current on-the-road technologies. The research and development is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow's automobiles will function as a unified system to improve fuel efficiency.

  12. Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

    NASA Astrophysics Data System (ADS)

    Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

    2015-11-01

    This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

  13. Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1990-01-01

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's.

  14. Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1990-01-01

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's

  15. Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Astrophysics Data System (ADS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's.

  16. Electric Power Generation Using Low Bandgap TPV Cells in a Gas-fired Heating Furnace

    NASA Astrophysics Data System (ADS)

    Qiu, K.; Hayden, A. C. S.

    2003-01-01

    Low bandgap TPV cells are preferred for electric power generation in TPV cogeneration systems. Recently, significant progress has been made in fabrication of low bandgap semiconductor TPV devices, such as InGaAsSb and InGaAs cells. However, it appears that only limited data are available in the literature with respect to the performance of these TPV cells in combustion-driven TPV systems. In the research presented in this paper, power generation using recently-developed InGaAsSb TPV cells has been investigated in a gas-fired space heating appliance. The combustion performance of the gas burner associated with a broadband radiator was evaluated experimentally. The radiant power density and radiant efficiency of the gas-heated radiator were determined at different degrees of exhaust heat recuperation. Heat recuperation is shown to have a certain effect on the combustion operation and radiant power output. The electric output characteristics of the InGaAsSb TPV devices were investigated under various combustion conditions. It was found that the cell short circuit density was greater than 1 A/cm2 at a radiator temperature of 930°C when an optical filter was used. An electric power density of 0.54 W/cm2 was produced at a radiator temperature of 1190°C. Furthermore, modeling calculations were carried out to reveal the influence of TPV cell bandgap and radiator temperature on power output and conversion efficiency. Finally, the design aspects of combustion-driven TPV systems were analyzed, showing that development of a special combustion device with high conversion level of fuel chemical energy to useful radiant energy is required, to improve further the system efficiency.

  17. Advanced Fuel Cycle Initiative - Projected Linear Heat Generation Rate and Burnup Calculations

    SciTech Connect

    Richard G. Ambrosek; Gray S. Chang; Debbie J. Utterbeck

    2005-02-01

    This report provides documentation of the physics analysis performed to determine the linear heat generation rate (LHGR) and burnup calculations for the Advanced Fuel Cycle Initiative (AFCI) tests, AFC-1D, AFC-1H, and AFC-1G. The AFC-1D and AFC-1H tests consists of low-fertile metallic fuel compositions and the AFC-1G test consists of non-fertile and low-fertile nitride compositions. These tests will be irradiated in the East Flux Trap (EFT) positions E1, E2, and E3, respectively, during Advanced Test Reactor (ATR) Cycle 135B.

  18. Electrical Equipment of Electrical Stations and Substations,

    DTIC Science & Technology

    1979-10-25

    possibility of the conversion of industry on the new, more advanced energy base . Thre-e-phasp current proved to be technically and economically more... energy up to large distances it was difficultly make as a result of the large heat losses in conduits/manifolds, then heat and power plants were...transmitted by the wires of smaller sections. Decrease energy losses in electric system. Since electric generators and receivers are constructed to the

  19. Advanced electric propulsion system concept for electric vehicles. Addendum 1: Voltage considerations

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Forbes, F. E.

    1980-01-01

    The two electric vehicle propulsion systems that best met cost and performance goals were examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 k W-hr. The highest battery specific energy (W-hr/kg) and the lowest cost ($/kW-hr) were obtained at the minimum voltage level. The flywheel system traction motor is a dc, mechanically commutated with shunt field control, and due to the flywheel the traction motor and the battery are not subject to extreme peaks of power demand. The basic system uses a permanent-magnet motor with electronic commutation supplied by an ac power control unit. In both systems battery cost were the major factor in system voltage selection, and a battery pack with the minimum voltage of 54 V produced the lowest life-cycle cost. The minimum life-cycle cost for the basic system with lead-acid batteries was $0.057/km and for the flywheel system was $0.037/km.

  20. Advanced Launch System (ALS): Electrical actuation and power systems improve operability and cost picture

    NASA Technical Reports Server (NTRS)

    Sundberg, Gale R.

    1990-01-01

    To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.

  1. Heating of Particulates by RF Magnetic Field and RF Electric Field

    NASA Astrophysics Data System (ADS)

    Tang, Wilkin; Bosman, Herman; Lau, Y. Y.; Gilgenbach, R. M.

    2004-11-01

    Microwave heating is an important industrial heating process for certain niche applications such as the sintering of ceramics and rubber vulcanization, and has potential uses in the treatment of mineral ores, heating of reagents and catalysts in chemical reactions, and regeneration of molecular sieves. Here, we examine microwave heating by placing a small, spherical particulate of a general complex permittivity and permeability at the center of a perfectly conducting spherical cavity. The dispersion relation for both the TE mode and TM mode is solved exactly. The damping rates of these modes immediately give the degree of absorption by the rf electric field and by the rf magnetic field, over a wide range of parameters, and from quasi-static to very high frequencies. It is found that, in general, whenever the resistive skin depth is much less than the radius of the particulate, heating by the rf magnetic field always dominates, whether the particulate is magnetic or nonmagnetic. Simple scaling laws have been derived and will be presented [H. Bosman et al., APL (to be published)].

  2. Dissolved gas exsolution to enhance gas production and transport during bench-scale electrical resistance heating

    NASA Astrophysics Data System (ADS)

    Hegele, P. R.; Mumford, K. G.

    2015-05-01

    Condensation of volatile organic compounds in colder zones can be detrimental to the performance of an in situ thermal treatment application for the remediation of chlorinated solvent source zones. A novel method to increase gas production and limit convective heat loss in more permeable, potentially colder, zones involves the injection and liberation of dissolved gas from solution during heating. Bench-scale electrical resistance heating experiments were performed with a dissolved carbon dioxide and sodium chloride solution to investigate exsolved gas saturations and transport regimes at elevated, but sub-boiling, temperatures. At sub-boiling temperatures, maximum exsolved gas saturations of Sg = 0.12 were attained, and could be sustained when the carbon dioxide solution was injected during heating rather than emplaced prior to heating. This gas saturation was estimated to decrease groundwater relative permeability to krw = 0.64. Discontinuous gas transport was observed above saturations of Sg = 0.07, demonstrating the potential of exsolved CO2 to bridge vertical gas transport through colder zones.

  3. Experimental Investigation of Pool Boiling Heat Transfer Enhancement in Microgravity in the Presence of Electric Fields

    NASA Technical Reports Server (NTRS)

    Herman, Cila

    1999-01-01

    In boiling high heat fluxes are possible driven by relatively small temperature differences, which make its use increasingly attractive in aerospace applications. The objective of the research is to develop ways to overcome specific problems associated with boiling in the low gravity environment by substituting the buoyancy force with the electric force to enhance bubble removal from the heated surface. Previous studies indicate that in terrestrial applications nucleate boiling heat transfer can be increased by a factor of 50, as compared to values obtained for the same system without electric fields. The goal of our research is to experimentally explore the mechanisms responsible for EHD heat transfer enhancement in boiling in low gravity conditions, by visualizing the temperature distributions in the vicinity of the heated surface and around the bubble during boiling using real-time holographic interferometry (HI) combined with high-speed cinematography. In the first phase of the project the influence of the electric field on a single bubble is investigated. Pool boiling is simulated by injecting a single bubble through a nozzle into the subcooled liquid or into the thermal boundary layer developed along the flat heater surface. Since the exact location of bubble formation is known, the optical equipment can be aligned and focused accurately, which is an essential requirement for precision measurements of bubble shape, size and deformation, as well as the visualization of temperature fields by HI. The size of the bubble and the frequency of bubble departure can be controlled by suitable selection of nozzle diameter and mass flow rate of vapor. In this approach effects due to the presence of the electric field can be separated from effects caused by the temperature gradients in the thermal boundary layer. The influence of the thermal boundary layer can be investigated after activating the heater at a later stage of the research. For the visualization experiments a

  4. Implications for Advanced Nursing Practice in the Patient with Heat Stress

    DTIC Science & Technology

    1993-05-01

    systemic vascular resistance), while elderly patients are hypodynamic (increased heart rate, decreased cardiac output and decreased systemic vascular...resistance). By the time elderly patients are seen, massive volume deficits may exist, requiring hemodynamic monitoring to differentiate pump...TITLE AND SUBTITLE 5. FUNDING NUMBERS Implications for Advanced Nursing Practice in the Patient with Heat Stress 6. AUTHOR(S) Patricia A Skelton S 7

  5. ECUT energy data reference series: high-temperature materials for advanced heat engines

    SciTech Connect

    Abarcar, R.B.; Hane, G.J.; Johnson, D.R.

    1984-07-01

    Information that describes the use of high-temperature materials in advanced heat engines for ground transportation applications is summarized. Applications discussed are: automobiles, light trucks, and medium and heavy trucks. The information provided on each of these modes includes descriptions of the average conversion efficiency of the engine, the capital stock, the amount of energy used, and the activity level as measured in ton-miles.

  6. Energy Savings and Economics of Advanced Control Strategies for Packaged Heat Pumps

    SciTech Connect

    Wang, Weimin; Huang, Yunzhi; Katipamula, Srinivas

    2012-10-31

    Pacific Northwest National Laboratory (PNNL), with funding from the U.S. Department of Energy’s (DOE’s) Building Technologies Program (BTP), evaluated a number of control strategies for packaged cooling equipment that can be implemented in an advanced controller, which can be retrofit into existing packaged heat pump units to improve their operational efficiency. This report documents the results of that analysis.

  7. ADVANCED HEAT TRANSFER TEST FACILITY, TRA666A. ELEVATIONS. ROOF FRAMING PLAN. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ADVANCED HEAT TRANSFER TEST FACILITY, TRA-666A. ELEVATIONS. ROOF FRAMING PLAN. CONCRETE BLOCK SIDING. SLOPED ROOF. ROLL-UP DOOR. AIR INTAKE ENCLOSURE ON NORTH SIDE. F.C. TORKELSON 842-MTR-666-A5, 8/1966. INL INDEX NO. 531-0666-00-851-152258, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  8. Life prediction methodology for ceramic components of advanced heat engines. Phase 1: Volume 2, Appendices

    SciTech Connect

    1995-03-01

    This volume presents the following appendices: ceramic test specimen drawings and schematics, mixed-mode and biaxial stress fracture of structural ceramics for advanced vehicular heat engines (U. Utah), mode I/mode II fracture toughness and tension/torsion fracture strength of NT154 Si nitride (Brown U.), summary of strength test results and fractography, fractography photographs, derivations of statistical models, Weibull strength plots for fast fracture test specimens, and size functions.

  9. Heat and mass transfer in a vertical double passage channel filled with electrically conducting fluid

    NASA Astrophysics Data System (ADS)

    Umavathi, Jawali C.; Kumar, J. Prathap; Sheremet, Mikhail A.

    2017-01-01

    This paper investigates the influence of first order chemical reaction in a vertical double passage channel in the presence of applied electric field. The wall and ambient medium are maintained at constant but different temperatures and concentrations and the heat and mass transfer occur from the wall to the medium. The channel is divided into two passages by means of a thin perfectly conducting baffle. The coupled non-linear ordinary differential equations are solved analytically by using regular perturbation method (PM) valid for small values of Brinkman number. To understand the flow structure for large values of Brinkman number the governing equations are also solved by differential transform method (DTM) which is a semi-analytical method. The effects of thermal Grashof number (GrT = 1 , 5 , 10 , 15), mass Grashof number (GrC = 1 , 5 , 10 , 15), Brinkman number (Br = 0 , 0.1 , 0.5 , 1), first order chemical reaction parameter (α = 0.1 , 0.5 , 1 , 1.5), Hartmann number (M = 4 , 6 , 8 , 10) and electrical field load parameter (E = - 2 , - 1 , 0 , 1 , 2) on the velocity, temperature and concentration profiles, volumetric flow rate, total heat rate, skin friction and Nusselt number are analyzed. It was found that the thermal Grashof number, mass Grashof number and Brinkman number enhances the flow whereas the Hartmann number and chemical reaction parameter suppresses the flow ​field. Also the obtained results have revealed that the heat transfer enhancement depends on the baffle position.

  10. Advanced Reactors-Intermediate Heat Exchanger (IHX) Coupling: Theoretical Modeling and Experimental Validation

    SciTech Connect

    Utgikar, Vivek; Sun, Xiaodong; Christensen, Richard; Sabharwall, Piyush

    2016-12-29

    The overall goal of the research project was to model the behavior of the advanced reactorintermediate heat exchange system and to develop advanced control techniques for off-normal conditions. The specific objectives defined for the project were: 1. To develop the steady-state thermal hydraulic design of the intermediate heat exchanger (IHX); 2. To develop mathematical models to describe the advanced nuclear reactor-IHX-chemical process/power generation coupling during normal and off-normal operations, and to simulate models using multiphysics software; 3. To develop control strategies using genetic algorithm or neural network techniques and couple these techniques with the multiphysics software; 4. To validate the models experimentally The project objectives were accomplished by defining and executing four different tasks corresponding to these specific objectives. The first task involved selection of IHX candidates and developing steady state designs for those. The second task involved modeling of the transient and offnormal operation of the reactor-IHX system. The subsequent task dealt with the development of control strategies and involved algorithm development and simulation. The last task involved experimental validation of the thermal hydraulic performances of the two prototype heat exchangers designed and fabricated for the project at steady state and transient conditions to simulate the coupling of the reactor- IHX-process plant system. The experimental work utilized the two test facilities at The Ohio State University (OSU) including one existing High-Temperature Helium Test Facility (HTHF) and the newly developed high-temperature molten salt facility.

  11. Energy-efficiency comparison of advanced ammonia heat-exchanger types

    SciTech Connect

    Panchal, C.; Rabas, T.

    1990-01-01

    Ammonia is the most cost-effective working fluid for many Rankine power cycles and is widely utilized in industrial refrigeration applications. For example, it was selected as the most advantageous working fluid for the comprehensive closed-cycle Ocean Thermal Energy Conversion investigations where the heat source and sink are the warm, surface seawater and the cold, deep seawater, respectively. An essential part of this investigation was to measure the performance of many advanced heat-exchanger types using ammonia as the working fluid and to compare these results with those for conventional shell-and-tube designs. This paper presents an overview of these experiments and their potential significance for improved energy efficiency for industrial refrigeration applications. The heat exchangers used for industrial refrigeration systems account for about 50% of the equipment cost. However, current practice is to use state-of-the-art designs -- the shell-and-tube type without enhanced tubes. Substantial energy savings are possible through the use of advanced ammonia evaporator and condenser heat-exchanger types. 31 refs., 10 figs., 6 tabs.

  12. Practical Considerations of Waste Heat Reuse for a Mars Mission Advanced Life Support System

    NASA Technical Reports Server (NTRS)

    Levri, Julie; Finn, Cory; Luna, Bernadette (Technical Monitor)

    2000-01-01

    Energy conservation is a key issue in design optimization of Advanced Life Support Systems (ALSS) for long-term space missions. By considering designs for conservation at the system level, energy saving opportunities arise that would otherwise go unnoticed. This paper builds on a steady-state investigation of system-level waste heat reuse in an ALSS with a low degree of crop growth for a Mars mission. In past studies, such a system has been defined in terms of technology types, hot and cold stream identification and stream energy content. The maximum steady-state potential for power and cooling savings within the system was computed via the Pinch Method. In this paper, several practical issues are considered for achieving a pragmatic estimate of total system savings in terms of equivalent system mass (ESM), rather than savings solely in terms of power and cooling. In this paper, more realistic ESM savings are computed by considering heat transfer inefficiencies during material transfer. An estimate of the steady-state mass, volume and crewtime requirements associated with heat exchange equipment is made by considering heat exchange equipment material type and configuration, stream flow characteristics and associated energy losses during the heat exchange process. Also, previously estimated power and cooling savings are adjusted to reflect the impact of such energy losses. This paper goes one step further than the traditional Pinch Method of considering waste heat reuse in heat exchangers to include ESM savings that occur with direct reuse of a stream. For example, rather than exchanging heat between crop growth lamp cooling air and air going to a clothes dryer, air used to cool crop lamps might be reused directly for clothes drying purposes. When thermodynamically feasible, such an approach may increase ESM savings by minimizing the mass, volume and crewtime requirements associated with stream routing equipment.

  13. Common station system for voltage and reactive power regulation at the Mosenergo TETs-27 heating and electric power plant

    SciTech Connect

    Krasnova, M. E.

    2009-05-15

    The system for common station regulation of the voltage and reactive power at the Mosenergo TETs-27 heating and electric power plant is described briefly. Features of the algorithms for this system, which uses programs and instrumentation from the automatic control system for the electrical equipment in the 450 MW power generation unit No. 3, are examined.

  14. Efficient, High-Torque Electric Vehicle Motor: Advanced Electric Vehicle Motors with Low or No Rare Earth Content

    SciTech Connect

    2012-01-01

    REACT Project: QM Power will develop a new type of electric motor with the potential to efficiently power future generations of EVs without the use of rare-earth-based magnets. Many of today’s EV motors use rare earth magnets to efficiently provide torque to the wheels. QM Power’s motors would contain magnets that use no rare earth minerals, are light and compact, and can deliver more power with greater efficiency and at reduced cost. Key innovations in this project include a new motor design with iron-based magnetic materials, a new motor control technique, and advanced manufacturing techniques that substantially reduce the cost of the motor. The ultimate goal of this project is to create a cost-effective EV motor that offers the rough peak equivalent of 270 horsepower.

  15. Advanced Energy and Water Recovery Technology from Low Grade Waste Heat

    SciTech Connect

    Dexin Wang

    2011-12-19

    The project has developed a nanoporous membrane based water vapor separation technology that can be used for recovering energy and water from low-temperature industrial waste gas streams with high moisture contents. This kind of exhaust stream is widely present in many industrial processes including the forest products and paper industry, food industry, chemical industry, cement industry, metal industry, and petroleum industry. The technology can recover not only the sensible heat but also high-purity water along with its considerable latent heat. Waste heats from such streams are considered very difficult to recover by conventional technology because of poor heat transfer performance of heat-exchanger type equipment at low temperature and moisture-related corrosion issues. During the one-year Concept Definition stage of the project, the goal was to prove the concept and technology in the laboratory and identify any issues that need to be addressed in future development of this technology. In this project, computational modeling and simulation have been conducted to investigate the performance of a nanoporous material based technology, transport membrane condenser (TMC), for waste heat and water recovery from low grade industrial flue gases. A series of theoretical and computational analyses have provided insight and support in advanced TMC design and experiments. Experimental study revealed condensation and convection through the porous membrane bundle was greatly improved over an impermeable tube bundle, because of the membrane capillary condensation mechanism and the continuous evacuation of the condensate film or droplets through the membrane pores. Convection Nusselt number in flue gas side for the porous membrane tube bundle is 50% to 80% higher than those for the impermeable stainless steel tube bundle. The condensation rates for the porous membrane tube bundle also increase 60% to 80%. Parametric study for the porous membrane tube bundle heat transfer

  16. Gas production and transport during bench-scale electrical resistance heating of water and trichloroethene.

    PubMed

    Hegele, P R; Mumford, K G

    2014-09-01

    The effective remediation of chlorinated solvent source zones using in situ thermal treatment requires successful capture of gas that is produced. Replicate electrical resistance heating experiments were performed in a thin bench-scale apparatus, where water was boiled and pooled dense non-aqueous phase liquid (DNAPL) trichloroethene (TCE) and water were co-boiled in unconsolidated silica sand. Quantitative light transmission visualization was used to assess gas production and transport mechanisms. In the water boiling experiments, nucleation, growth and coalescence of the gas phase into connected channels were observed at critical gas saturations of Sgc=0.233±0.017, which allowed for continuous gas transport out of the sand. In experiments containing a colder region above a target heated zone, condensation prevented the formation of steam channels and discrete gas clusters that mobilized into colder regions were trapped soon after discontinuous transport began. In the TCE-water experiments, co-boiling at immiscible fluid interfaces resulted in discontinuous gas transport above the DNAPL pool. Redistribution of DNAPL was also observed above the pool and at the edge of the vapor front that propagated upwards through colder regions. These results suggest that the subsurface should be heated to water boiling temperatures to facilitate gas transport from specific locations of DNAPL to extraction points and reduce the potential for DNAPL redistribution. Decreases in electric current were observed at the onset of gas phase production, which suggests that coupled electrical current and temperature measurements may provide a reliable metric to assess gas phase development.

  17. Gas production and transport during bench-scale electrical resistance heating of water and trichloroethene

    NASA Astrophysics Data System (ADS)

    Hegele, P. R.; Mumford, K. G.

    2014-09-01

    The effective remediation of chlorinated solvent source zones using in situ thermal treatment requires successful capture of gas that is produced. Replicate electrical resistance heating experiments were performed in a thin bench-scale apparatus, where water was boiled and pooled dense non-aqueous phase liquid (DNAPL) trichloroethene (TCE) and water were co-boiled in unconsolidated silica sand. Quantitative light transmission visualization was used to assess gas production and transport mechanisms. In the water boiling experiments, nucleation, growth and coalescence of the gas phase into connected channels were observed at critical gas saturations of Sgc = 0.233 ± 0.017, which allowed for continuous gas transport out of the sand. In experiments containing a colder region above a target heated zone, condensation prevented the formation of steam channels and discrete gas clusters that mobilized into colder regions were trapped soon after discontinuous transport began. In the TCE-water experiments, co-boiling at immiscible fluid interfaces resulted in discontinuous gas transport above the DNAPL pool. Redistribution of DNAPL was also observed above the pool and at the edge of the vapor front that propagated upwards through colder regions. These results suggest that the subsurface should be heated to water boiling temperatures to facilitate gas transport from specific locations of DNAPL to extraction points and reduce the potential for DNAPL redistribution. Decreases in electric current were observed at the onset of gas phase production, which suggests that coupled electrical current and temperature measurements may provide a reliable metric to assess gas phase development.

  18. Experimental demonstration of a multiphysics cloak: manipulating heat flux and electric current simultaneously.

    PubMed

    Ma, Yungui; Liu, Yichao; Raza, Muhammad; Wang, Yudong; He, Sailing

    2014-11-14

    Invisible cloaks have been widely explored in many different physical systems but usually for a single phenomenon for one device. In this Letter we make an experimental attempt to show a multidisciplinary framework that has the capability to simultaneously respond to two different physical excitations according to predetermined scenarios. As a proof of concept, we implement an electric-thermal bifunctional device that can guide both electric current and heat flux "across" a strong 'scatterer' (air cavity) and restore their original diffusion directions as if nothing exists along the paths, thus rendering dual cloaking effects for objects placed inside the cavity. This bifunctional cloaking performance is also numerically verified for a line-source nonuniform excitation. Our results and the fabrication technique presented here will help broaden the current research scope for multiple disciplines and may pave a way to manipulate multiple flows and create new functional devices, e.g., for on-chip applications.

  19. Heating-up Synthesis of MoS2 Nanosheets and Their Electrical Bistability Performance

    NASA Astrophysics Data System (ADS)

    Li, Xu; Tang, Aiwei; Li, Jiantao; Guan, Li; Dong, Guoyi; Teng, Feng

    2016-03-01

    Molybdenum disulfide (MoS2) nanosheets were synthesized by using a simple heating-up approach, in which 1-dodecanethiol (DDT) was used not only as a sulfur source but also as the surface ligand. The sheet-like morphology was confirmed by the transmission electron microscopy (TEM) and atomic force microscopy (AFM) results, and the X-ray diffraction (XRD) patterns and Raman spectrum were employed to characterize the structure of the as-synthesized MoS2 nanosheets. The as-obtained MoS2 nanosheets blending with a polymer could be used to fabricate an electrically bistable device through a simple spin-coating method, and the device exhibited an obvious electrical bistability in the I-V curve. The charge transport of the device was discussed based on the organic electronic models.

  20. The performance of solar thermal electric power systems employing small heat engines

    NASA Technical Reports Server (NTRS)

    Pons, R. L.

    1980-01-01

    The paper presents a comparative analysis of small (10 to 100 KWe) heat engines for use with a solar thermal electric system employing the point-focusing, distributed receiver (PF-DR) concept. Stirling, Brayton, and Rankine cycle engines are evaluated for a nominal overall system power level of 1 MWe, although the concept is applicable to power levels up to at least 10 MWe. Multiple concentrators are electrically connected to achieve the desired plant output. Best performance is achieved with the Stirling engine, resulting in a system Levelized Busbar Energy Cost of just under 50 mills/kWH and a Capital Cost of $900/kW, based on the use of mass-produced components. Brayton and Rankine engines show somewhat less performance but are viable alternatives with particular benefits for special applications. All three engines show excellent performance for the small community application.

  1. Numerical analysis of the electrical failure of a metallic nanowire mesh due to Joule heating.

    PubMed

    Li, Yuan; Tsuchiya, Kaoru; Tohmyoh, Hironori; Saka, Masumi

    2013-08-30

    To precisely examine the electrical failure behavior of a metallic nanowire mesh induced by Joule heating (i.e., melting), a previously developed numerical method was modified with regard to the maximum temperature in the mesh and the electrical resistivity of the nanowire. A sample case of an Ag nanowire mesh under specific working conditions was analyzed with highly accurate numerical results. By monitoring the temperature in the mesh, the current required to trigger the melting of a mesh segment (i.e., the melting current) could be obtained. The melting process of a mesh equipped with a current source during actual operation was predicted on the basis of the obtained relationship between the melting current and the corresponding melting voltage in the numerical melting process. Local unstable and stable melting could be precisely identified for both the current-controlled and voltage-controlled current sources in the present example.

  2. CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES: Electric-Current-Induced Heat Generation in Kondo Regime

    NASA Astrophysics Data System (ADS)

    Chen, Qiao; Zhang, Ya-Min

    2010-07-01

    Using the nonequilibrium Green's function technique, we investigate the current induced heat generation in Kondo regime. The Kondo effect influences the heat generation significantly. In the curve of heat generation versus the bias, a negative differential of the heat generation is exhibited. The symmetry of the heat generation is destroyed by the strong electron-electron interaction and the electron-phonon interaction.

  3. Balance mathematical model for the heat regime of cold rolling of electrical steel strips in a reversing mill

    NASA Astrophysics Data System (ADS)

    Garber, E. A.; Aleshin, A. E.; Degtev, S. S.; Traino, A. I.

    2013-11-01

    A mathematical model is developed to describe the heat regime of a reversing cold-rolling mill that takes into account the substantial differences between the heat processes occurring in reversing and continuous mills. Model and heat balance equations are used to calculate the strip temperature in passes and the temperature and the heat profile of rolls as functions of the rolling regime parameters and the heat-transfer coefficients that characterize the heat exchange between a strip, rolls, and lubricant-cooling agents and depend on the cooling system parameters of a mill. The model can be used to find a heat regime favorable for achieving the required final magnetic properties of electrical steel. The efficiency of the factors affecting the heat regime in rolling is studied.

  4. Thermomagnetic conversion of low-grade waste heat into electrical power

    NASA Astrophysics Data System (ADS)

    El Achkar, G.; Dianoux, A.; Kheiri, A.; Maillet, D.; Mazet, T.; Colasson, S.; Feidt, M.; Rado, C.; Servant, F.; Paul-Boncour, V.

    2016-09-01

    A theoretical study relying on the thermal modelling of a Curie wheel, used for the conversion of low-grade waste heat into electrical power, is presented in this paper. It allows understanding the thermal behaviour of a Curie wheel operating in steady state in order to optimise its design. To this end, a stationary one-dimensional analytical thermal model, based on a Lagrangian approach, was developed. It allows determining the local distribution over time of the temperature in the magnetocaloric material exposed to a periodic sinusoidal heat source. Thanks to this model, the effects of different parameters (nature of the magnetocaloric material, nature and temperature of the fluid) were highlighted and studied.

  5. Physical and chemical changes to rock near electrically heated boreholes at Spent Fuel Test-Climax

    SciTech Connect

    Beiriger, J.M.; Durham, W.B.; Ryerson, F.J.

    1985-01-01

    Sections of Climax Stock quartz monzonite taken from the vicinity of two electrically heated boreholes at Spent Fuel Test-Climax (SFT-C) have been studied by scanning electron microscopy and optical microscopy for signs of changes in crack structure and in mineralogy resulting from operations at SFT-C. The crack structure, as measured by density of cracks and average crack lengths was found not to have changed as a result of heating, regardless of distance from the heater hole. However, rock near the heater borehole sampled in the north heater drift was found to be more cracked than rock near the borehole sampled in the south heater drift. Mineralogically, the post-test samples are identical to the pre-test samples. No new phases have been formed as a result of the test. 10 refs., 6 figs., 8 tabs.

  6. Research on temperature control with numerical regulators in electric resistance furnaces with indirect heating

    NASA Astrophysics Data System (ADS)

    Diniş, C. M.; Popa, G. N.; Iagăr, A.

    2016-02-01

    The paper is an analysis of two-positions (hysteresis) regulators, self-tuned PID controller and PID controller for temperature control used for indirect heat resistance furnaces. For PID controller was used three methods of tuning: Ziegler-Nichols step response model, Cohen-Coon tuning rules and Ziegler-Nichols tuning rules. In experiments it used an electric furnace with indirect heating with active power of resistance of 1 kW/230V AC and a numerical temperature regulator AT-503 type (ANLY). It got a much better temperature control when using the Cohen-Coon tuning rules method than those of Ziegler-Nichols step response method and Ziegler-Nichols tuning rules method.

  7. Transverse eV ion heating by random electric field fluctuations in the plasmasphere

    NASA Astrophysics Data System (ADS)

    Artemyev, A. V.; Mourenas, D.; Agapitov, O. V.; Blum, L.

    2017-02-01

    Charged particle acceleration in the Earth inner magnetosphere is believed to be mainly due to the local resonant wave-particle interaction or particle transport processes. However, the Van Allen Probes have recently provided interesting evidence of a relatively slow transverse heating of eV ions at distances about 2-3 Earth radii during quiet times. Waves that are able to resonantly interact with such very cold ions are generally rare in this region of space, called the plasmasphere. Thus, non-resonant wave-particle interactions are expected to play an important role in the observed ion heating. We demonstrate that stochastic heating by random transverse electric field fluctuations of whistler (and possibly electromagnetic ion cyclotron) waves could explain this weak and slow transverse heating of H+ and O+ ions in the inner magnetosphere. The essential element of the proposed model of ion heating is the presence of trains of random whistler (hiss) wave packets, with significant amplitude modulations produced by strong wave damping, rapid wave growth, or a superposition of wave packets of different frequencies, phases, and amplitudes. Such characteristics correspond to measured characteristics of hiss waves in this region. Using test particle simulations with typical wave and plasma parameters, we demonstrate that the corresponding stochastic transverse ion heating reaches 0.07-0.2 eV/h for protons and 0.007-0.015 eV/h for O+ ions. This global temperature increase of the Maxwellian ion population from an initial Ti˜0.3 eV could potentially explain the observations.

  8. Indiana Advanced Electric Vehicle Training and Education Consortium (I-AEVtec)

    SciTech Connect

    Caruthers, James; Dietz, J.; Pelter, Libby; Chen, Jie; Roberson, Glen; McGinn, Paul; Kizhanipuram, Vinodegopal

    2013-01-31

    The Indiana Advanced Electric Vehicle Training and Education Consortium (I-AEVtec) is an educational partnership between six universities and colleges in Indiana focused on developing the education materials needed to support electric vehicle technology. The I-AEVtec has developed and delivered a number of degree and certificate programs that address various aspects of electric vehicle technology, including over 30 new or significantly modified courses to support these programs. These courses were shared on the SmartEnergyHub. The I-AEVtec program also had a significant outreach to the community with particular focus on K12 students. Finally, the evGrandPrix was established which is a university/college student electric go-kart race, where the students get hands-on experience in designing, building and racing electric vehicles. The evGrandPrix now includes student teams from across the US as well as from Europe and it is currently being held on Opening Day weekend for the Indy500 at the Indianapolis Motor Speedway.

  9. Heat and electricity from the sun using parabolic dish collector systems

    NASA Technical Reports Server (NTRS)

    Truscello, V. C.; Williams, A. N.

    1979-01-01

    The paper investigates point focus distributed receiver (PFDR) solar thermal technology for the production of electric power and of industrial process heat. Attention is given to a thermal systems project conducted by JPL under DOE sponsorship. It is reported that project emphasis is on the development of cost-effective systems which will accelerate the commercialization and industrialization of plants up to 10 MWe, using parabolic dish collectors. Also discussed are the characteristics of PFDR systems, the cost targets for major systems hardware, and markets for this technology. Finally, the present system status of the technology development effort is discussed.

  10. Historical Review of Electric Household Appliances using Induction-Heating and Future Challenging Trends

    NASA Astrophysics Data System (ADS)

    Hirota, Izuo; Yamashita, Hidekazu; Omori, Hideki; Nakaoka, Mutsuo

    This paper presents historical progress on technology evolution of the electric and electronic household appliances using the inverter, especially for Induction-Heating applications, which have been put in practical use as the desk-top cooker for the first time at home in 1974 until being applied to the rice cooker and the multi-burner cooking heater. It also describes the future innovative evolution of the power semiconductor switching devices and the inverter circuit topologies supporting its progressive developments. Looking back its progress, the future trends on consumer power electronics is discussed on the practical problem in the future.

  11. Effect of heat treatment on structure, surface composition, infrared emission and surface electrical properties of tourmaline

    NASA Astrophysics Data System (ADS)

    He, Dengliang; Liu, Shuxin

    2017-02-01

    Crystal structure, surface composition, infrared emission properties and surface electrical properties of tourmaline from Guangxi of China, when subjected to heat treatment in air atmosphere had been studied by some methods, including X-ray fluorescence spectrum (XRF), X-ray diffraction (XRD) meter, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), energy dispersion spectroscopy (EDS), scanning electron microscope (SEM) and Zeta potential analyzer, etc. Experimental results show that the unit cell of tourmaline would shrink during heat treatment because Fe2+ were oxidized. Moreover, the Fe3+/Fetotal inside tourmaline can be raised after treatment. Infrared normal total emissivity of tourmaline reaches 0.87, and infrared radiation energy density is 4.56 × 102W/m2. It can maintain excellent infrared emission properties at high temperature. Simultaneously, tourmaline presents negative Zeta potential in the aqueous solution, and its Zeta potential reaches ‑18.04 mV. Zeta potential of tourmaline was increased to ‑24.83 mV after heat treatment at 400∘C, and decrease to ‑11.78 mV after heat treatment at 600∘C. These findings may provide reference data for tourmaline’s application in the field of functional materials.

  12. Enhanced O2+ loss at Mars due to an ambipolar electric field from electron heating

    NASA Astrophysics Data System (ADS)

    Ergun, R. E.; Andersson, L. A.; Fowler, C. M.; Woodson, A. K.; Weber, T. D.; Delory, G. T.; Andrews, D. J.; Eriksson, A. I.; McEnulty, T.; Morooka, M. W.; Stewart, A. I. F.; Mahaffy, P. R.; Jakosky, B. M.

    2016-05-01

    Recent results from the MAVEN Langmuir Probe and Waves instrument suggest higher than predicted electron temperatures (Te) in Mars' dayside ionosphere above ~180 km in altitude. Correspondingly, measurements from Neutral Gas and Ion Mass Spectrometer indicate significant abundances of O2+ up to ~500 km in altitude, suggesting that O2+ may be a principal ion loss mechanism of oxygen. In this article, we investigate the effects of the higher Te (which results from electron heating) and ion heating on ion outflow and loss. Numerical solutions show that plasma processes including ion heating and higher Te may greatly increase O2+ loss at Mars. In particular, enhanced Te in Mars' ionosphere just above the exobase creates a substantial ambipolar electric field with a potential (eΦ) of several kBTe, which draws ions out of the region allowing for enhanced escape. With active solar wind, electron, and ion heating, direct O2+ loss could match or exceed loss via dissociative recombination of O2+. These results suggest that direct loss of O2+ may have played a significant role in the loss of oxygen at Mars over time.

  13. Development of Advanced Thermal and Environmental Barrier Coatings Using a High-Heat-Flux Testing Approach

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming; Miller, Robert A.

    2003-01-01

    The development of low conductivity, robust thermal and environmental barrier coatings requires advanced testing techniques that can accurately and effectively evaluate coating thermal conductivity and cyclic resistance at very high surface temperatures (up to 1700 C) under large thermal gradients. In this study, a laser high-heat-flux test approach is established for evaluating advanced low conductivity, high temperature capability thermal and environmental barrier coatings under the NASA Ultra Efficient Engine Technology (UEET) program. The test approach emphasizes the real-time monitoring and assessment of the coating thermal conductivity, which initially rises under the steady-state high temperature thermal gradient test due to coating sintering, and later drops under the cyclic thermal gradient test due to coating cracking/delamination. The coating system is then evaluated based on damage accumulation and failure after the combined steady-state and cyclic thermal gradient tests. The lattice and radiation thermal conductivity of advanced ceramic coatings can also be evaluated using laser heat-flux techniques. The external radiation resistance of the coating is assessed based on the measured specimen temperature response under a laser- heated intense radiation-flux source. The coating internal radiation contribution is investigated based on the measured apparent coating conductivity increases with the coating surface test temperature under large thermal gradient test conditions. Since an increased radiation contribution is observed at these very high surface test temperatures, by varying the laser heat-flux and coating average test temperature, the complex relation between the lattice and radiation conductivity as a function of surface and interface test temperature may be derived.

  14. DOE FreedomCAR and vehicle technologies program advanced power electronic and electrical machines annual review report

    SciTech Connect

    Olszewski, Mitch

    2006-10-11

    This report is a summary of the Review Panel at the FY06 DOE FreedomCAR and Vehicle Technologies (FCVT) Annual Review of Advanced Power Electronics and Electric Machine (APEEM) research activities held on August 15-17, 2006.

  15. High voltage-power frequency electrical heating in-situ conversion technology of oil shale

    NASA Astrophysics Data System (ADS)

    Sun, Youhong; Yang, Yang; Lopatin, Vladimir; Guo, Wei; Liu, Baochang; Yu, Ping; Gao, Ke; Ma, Yinlong

    2014-05-01

    With the depletion of conventional energy sources,oil shale has got much attention as a new type of energy resource,which is rich and widespread in the world.The conventional utilization of oil shale is mainly focused on resorting to produce shale oil and fuel gas with low extraction efficiency about one in a million due to many shortcomings and limitations.And the in-situ conversion of oil shale,more environmentally friendly,is still in the experimental stage.High voltage-power frequency electrical heating in-situ conversion of oil shale is a new type of in-situ pyrolysis technology.The main equipment includes a high voltage-power frequency generator and interior reactor. The high voltage-power frequency generator can provide a voltage between 220-8000 V which can be adjusted in real time according to the actual situation.Firstly,high voltage is used to breakdown the oil shale to form a dendritic crack between two electrodes providing a conductive channel inside the oil shale rock.And then the power frequency(220V) is used to generate the electric current for heating the internal surface of conductive channel,so that the energy can be transmitted to the surrounding oil shale.When the temperature reaches 350 degree,the oil shale begins to pyrolysis.In addition,the temperature in the conductive channel can be extremely high with high voltage,which makes the internal surface of conductive channel graphitization and improves its heat conduction performance.This technology can successfully make the oil shale pyrolysis, based on a lot of lab experiments,and also produce the combustible shale oil and fuel gas.Compared to other in-situ conversion technology,this method has the following advantages: high speed of heating oil shale,the equipment underground is simple,and easy to operate;it can proceed without the limitation of shale thickness, and can be used especially in the thin oil shale reservoir;the heating channel is parallel to the oil shale layers,which has more

  16. EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF NEW POWER CYCLES AND ADVANCED FALLING FILM HEAT EXCHANGERS

    SciTech Connect

    Arsalan Razani; Kwang J. Kim

    2001-12-01

    The final report for the DOE/UNM grant number DE-FG26-98FT40148 discusses the accomplishments of both the theoretical analysis of advanced power cycles and experimental investigation of advanced falling film heat exchangers. This final report also includes the progress report for the third year (period of October 1, 2000 to September 30, 2001). Four new cycles were studied and two cycles were analyzed in detail based on the second law of thermodynamics. The first cycle uses a triple combined cycle, which consists of a topping cycle (Brayton/gas), an intermediate cycle (Rankine/steam), and a bottoming cycle (Rankine/ammonia). This cycle can produce high efficiency and reduces the irreversibility of the Heat Recovery Steam Generator (HRSC) of conventional combined power cycles. The effect of important system parameters on the irreversibility distribution of all components in the cycle under reasonable practical constraints was evaluated. The second cycle is a combined cycle, which consists of a topping cycle (Brayton/gas) and a bottoming cycle (Rankine/ammonia) with integrated compressor inlet air cooling. This innovative cycle can produce high power and efficiency. This cycle is also analyzed and optimized based on the second the second law to obtain the irreversibility distribution of all components in the cycle. The results of the studies have been published in peer reviewed journals and ASME conference proceeding. Experimental investigation of advanced falling film heat exchangers was conducted to find effective additives for steam condensation. Four additives have been selected and tested in a horizontal tube steam condensation facility. It has been observed that heat transfer additives have been shown to be an effective way to increase the efficiency of conventional tube bundle condenser heat exchangers. This increased condensation rate is due to the creation of a disturbance in the liquid condensate surround the film. The heat transfer through such a film has

  17. Advances in series resonant inverter technology and its effect on spacecraft employing electric propulsion

    NASA Technical Reports Server (NTRS)

    Robson, R. R.

    1982-01-01

    The efficiency of transistorized Series Resonant Inverters (SRIs), which is higher than that of silicon-controlled rectifier alternatives, reduces spacecraft radiator requirements by 40% and may eliminate the need for heat pipes on 30-cm ion thruster systems. Recently developed 10- and 25-kW inverters have potential applications in gas thrusters, and represent the first spaceborne SRI designs for such power levels. Attention is given to the design and control system approaches employed in these inverter designs to improve efficiency and reduce weight, along with the impact of such improved parameters on electric propulsion systems.

  18. Factors affecting gas migration and contaminant redistribution in heterogeneous porous media subject to electrical resistance heating.

    PubMed

    Munholland, Jonah L; Mumford, Kevin G; Kueper, Bernard H

    2016-01-01

    A series of intermediate-scale laboratory experiments were completed in a two-dimensional flow cell to investigate gas production and migration during the application of electrical resistance heating (ERH) for the removal of dense non-aqueous phase liquids (DNAPLs). Experiments consisted of heating water in homogeneous silica sand and heating 270 mL of trichloroethene (TCE) and chloroform (CF) DNAPL pools in heterogeneous silica sands, both under flowing groundwater conditions. Spatial and temporal distributions of temperature were measured using thermocouples and observations of gas production and migration were collected using front-face image capture throughout the experiments. Post-treatment soil samples were collected and analyzed to assess DNAPL removal. Results of experiments performed in homogeneous sand subject to different groundwater flow rates showed that high groundwater velocities can limit subsurface heating rates. In the DNAPL pool experiments, temperatures increased to achieve DNAPL-water co-boiling, creating estimated gas volumes of 131 and 114 L that originated from the TCE and CF pools, respectively. Produced gas migrated vertically, entered a coarse sand lens and subsequently migrated laterally beneath an overlying capillary barrier to outside the heated treatment zone where 31-56% of the original DNAPL condensed back into a DNAPL phase. These findings demonstrate that layered heterogeneity can potentially facilitate the transport of contaminants outside the treatment zone by mobilization and condensation of gas phases during ERH applications. This underscores the need for vapor phase recovery and/or control mechanisms below the water table during application of ERH in heterogeneous porous media during the co-boiling stage, which occurs prior to reaching the boiling point of water.

  19. Factors affecting gas migration and contaminant redistribution in heterogeneous porous media subject to electrical resistance heating

    NASA Astrophysics Data System (ADS)

    Munholland, Jonah L.; Mumford, Kevin G.; Kueper, Bernard H.

    2016-01-01

    A series of intermediate-scale laboratory experiments were completed in a two-dimensional flow cell to investigate gas production and migration during the application of electrical resistance heating (ERH) for the removal of dense non-aqueous phase liquids (DNAPLs). Experiments consisted of heating water in homogeneous silica sand and heating 270 mL of trichloroethene (TCE) and chloroform (CF) DNAPL pools in heterogeneous silica sands, both under flowing groundwater conditions. Spatial and temporal distributions of temperature were measured using thermocouples and observations of gas production and migration were collected using front-face image capture throughout the experiments. Post-treatment soil samples were collected and analyzed to assess DNAPL removal. Results of experiments performed in homogeneous sand subject to different groundwater flow rates showed that high groundwater velocities can limit subsurface heating rates. In the DNAPL pool experiments, temperatures increased to achieve DNAPL-water co-boiling, creating estimated gas volumes of 131 and 114 L that originated from the TCE and CF pools, respectively. Produced gas migrated vertically, entered a coarse sand lens and subsequently migrated laterally beneath an overlying capillary barrier to outside the heated treatment zone where 31-56% of the original DNAPL condensed back into a DNAPL phase. These findings demonstrate that layered heterogeneity can potentially facilitate the transport of contaminants outside the treatment zone by mobilization and condensation of gas phases during ERH applications. This underscores the need for vapor phase recovery and/or control mechanisms below the water table during application of ERH in heterogeneous porous media during the co-boiling stage, which occurs prior to reaching the boiling point of water.

  20. Studies of dynamic contact of ceramics and alloys for advanced heat engines. Final report

    SciTech Connect

    Gaydos, P.A.; Dufrane, K.F.

    1993-06-01

    Advanced materials and coatings for low heat rejection engines have been investigated for almost a decade. Much of the work has concentrated on the critical wear interface between the piston ring and cylinder liner. Simplified bench tests have identified families of coatings with high temperature wear performance that could meet or exceed that of conventional engine materials at today`s operating temperatures. More recently, engine manufacturers have begun to optimize material combinations and manufacturing processes so that the materials not only have promising friction and wear performance but are practical replacements for current materials from a materials and manufacturing cost standpoint. In this study, the advanced materials supplied by major diesel engine manufacturers were evaluated in an experimental apparatus that simulates many of the in-cylinder conditions of a low heat rejection diesel engine. Results include ring wear factors and average dynamic friction coefficients measured at intervals during the test. These results are compared with other advanced materials tested in the past as well as the baseline wear of current engines. Both fabricated specimens and sections of actual ring and cylinder liners were used in the testing. Observations and relative friction and wear performance of the individual materials are provided.

  1. Yeast cell inactivation related to local heating induced by low-intensity electric fields with long-duration pulses.

    PubMed

    Guyot, Stéphane; Ferret, Eric; Boehm, Jean-Baptiste; Gervais, Patrick

    2007-01-25

    The effects of electric field (EF) treatments on Saccharomyces cerevisiae viability were investigated using a PG200 electroporator (Hoefer Scientific Instrument, San Fransisco, CA, USA) with specific attention to induced thermal effects on cell death. Lethal electric fields (1.5 kV cm(-1) for 5 s) were shown to cause heat variations in the cell suspension medium (water+glycerol), while corresponding classical thermal treatments at equivalent temperatures had no effect on the cells viability. Variations of the electrical conductivity of the intra- and extracellular matrix caused by ions and solutes transfer across the membrane were shown to be involved in the observed heating. The results permitted to build a theoretical model for the temperature variations induced by electric fields. Using this model and the electrical conductivity of the different media, a plausible explanation of the cell death induced by low-intensity electric fields with long-duration pulses has been proposed. Indeed, cell mortality could in part be caused by direct and indirect effects of electric fields. Direct effects are related to well known electromechanical phenomena, whereas indirect effects are related to secondary thermal stress caused by plasma membrane thermoporation. This thermoporation was attributed to electrical conductivity variations and the corresponding intracellular heating.

  2. The effects of regional insolation differences upon advanced solar thermal electric power plant performance and energy costs

    NASA Technical Reports Server (NTRS)

    Latta, A. F.; Bowyer, J. M.; Fujita, T.; Richter, P. H.

    1979-01-01

    The performance and cost of the 10 MWe advanced solar thermal electric power plants sited in various regions of the continental United States were determined. The regional insolation data base is discussed. A range for the forecast cost of conventional electricity by region and nationally over the next several cades are presented.

  3. FY2013 Advanced Power Electronics and Electric Motors R&D Annual Progress Report

    SciTech Connect

    Rogers, Susan A.

    2014-02-01

    The Advanced Power Electronics and Electric Motors (APEEM) technology area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE), electric motor, and traction drive system (TDS) technologies that will leapfrog current on-the-road technologies, leading to lower cost and better efficiency in transforming battery energy to useful work. The research and development (R&D) is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency through research in more efficient TDSs.

  4. Performance and life evaluation of advanced battery technologies for electric vehicle applications

    NASA Astrophysics Data System (ADS)

    Deluca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F.; Webster, C. E.

    Advanced battery technology evaluations are performed under simulated electric vehicle (EV) operating conditions at the Argonne Analysis and Diagnostic Laboratory (ADL). The ADL provides a common basis for both performance characterization and life evaluation with unbiased application of tests and analyses. This paper summarizes the performance characterizations and life evaluations conducted in 1990 on nine single cells and fifteen 3- to 360-cell modules that encompass six technologies: (Na/S, Zn/Br, Ni/Fe, Ni/Cd, Ni-metal hydride, and lead-acid). These evaluations were performed for the Department of Energy and Electric Power Research Institute. The results provide battery users, developers, and program managers an interim measure of the progress being made in battery R and D programs, a comparison of battery technologies, and a source of basic data for modelling and continuing R and D.

  5. Performance and life evaluation of advanced battery technologies for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Gillie, K.R.; Kulaga, J.E.; Smaga, J.A.; Tummillo, A.F.; Webster, C.E.

    1991-01-01

    Advanced battery technology evaluations are performed under simulated electric vehicle (EV) operating conditions at the Argonne Analysis Diagnostic Laboratory (ADL). The ADL provides a common basis for both performance characterization and life evaluation with unbiased application of tests and analyses. This paper summarizes the performance characterizations and life evaluations conducted in 1990 on nine single cells and fifteen 3- to 360-cell modules that encompass six technologies (Na/S, Zn/Br, Ni/Fe, Ni/Cd, Ni-metal hydride, and lead-acid). These evaluations were performed for the Department of Energy and Electric Power Research Institute. The results provide battery users, developers, and program managers an interim measure of the progress being made in battery R D programs, a comparison of battery technologies, and a source of basic data for modelling and continuing R D. 1 ref., 4 figs., 2 tabs.

  6. EXPERIMENTAL AND THEORETICAL INVESTIGATIONS OF NEW POWER CYCLES AND ADVANCED FALLING FILM HEAT EXCHANGERS

    SciTech Connect

    Arsalan Razani; Kwang J. Kim

    2000-10-28

    The annual progress report for the period of October 1, 1999 to September 30, 2000 on DOE/UNM grant number DE-FG26-98FT40148 discusses the progress on both the theoretical analysis of advanced power cycles and the experimental investigation of advanced falling film heat exchangers. The previously developed computer program for the triple cycle, based on the air standard cycle assumption, was modified to include actual air composition (%77.48 N{sub 2}, %20.59 O{sub 2}, %1.9 H{sub 2}O, and %0.03 CO{sub 2}). The actual combustion products were used in exergy analysis of the triple cycle. The effect of steam injection into the combustion chamber on its irreversibility, and the irreversibility of the entire cycle, was evaluated. A more practical fuel inlet condition and a better position of the feedwater heater in the steam cycle were used in the modified cycle. The effect of pinch point and the temperature difference between the combustion products, as well as the steam in the heat recovery steam generator on irreversibility of the cycle were evaluated. Design, construction, and testing of the multitube horizontal falling film condenser facility were completed. Two effective heat transfer additives (2-ethyl-1-hexanol and alkyl amine) were identified and tested for steam condensation. The test results are included. The condenser was designed with twelve tubes in an array of three horizontals and four verticals, with a 2-inch horizontal and 1.5-inch vertical in-line pitch. By using effective additives, the condensation heat transfer rate can be augmented as much as 30%, as compared to a heat transfer that operated without additives under the same operating condition. When heat transfer additives function effectively, the condensate-droplets become more dispersed and have a smaller shape than those produced without additives. These droplets, unlike traditional turbulence, start at the top portion of the condenser tubes and cover most of the tubes. Such a flow behavior can

  7. Technology Development Roadmap for the Advanced High Temperature Reactor Secondary Heat Exchanger

    SciTech Connect

    P. Sabharwall; M. McCllar; A. Siahpush; D. Clark; M. Patterson; J. Collins

    2012-09-01

    This Technology Development Roadmap (TDRM) presents the path forward for deploying large-scale molten salt secondary heat exchangers (MS-SHX) and recognizing the benefits of using molten salt as the heat transport medium for advanced high temperature reactors (AHTR). This TDRM will aid in the development and selection of the required heat exchanger for: power production (the first anticipated process heat application), hydrogen production, steam methane reforming, methanol to gasoline production, or ammonia production. This TDRM (a) establishes the current state of molten salt SHX technology readiness, (b) defines a path forward that systematically and effectively tests this technology to overcome areas of uncertainty, (c) demonstrates the achievement of an appropriate level of maturity prior to construction and plant operation, and (d) identifies issues and prioritizes future work for maturing the state of SHX technology. This study discusses the results of a preliminary design analysis of the SHX and explains the evaluation and selection methodology. An important engineering challenge will be to prevent the molten salt from freezing during normal and off-normal operations because of its high melting temperature (390°C for KF ZrF4). The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The need for efficiency, compactness, and safety challenge the capabilities of existing heat exchanger technology. The description of potential heat exchanger configurations or designs (such as printed circuit, spiral or helical coiled, ceramic, plate and fin, and plate type) were covered in an earlier report (Sabharwall et al. 2011). Significant future work, much of which is suggested in this report, is needed before the benefits and full potential of the AHTR can be realized. The execution of this TDRM will focuses

  8. Do Membranes Dream of Electric Tubes? Advanced Membranes Using Carbon Nanotube - Polymer Nanocomposites

    NASA Astrophysics Data System (ADS)

    de Lannoy, Charles-Francois Pedro Claude Karolek Ghislain

    Membrane technologies represent an energy efficient, effective solution for treating municipal and commercial waters/wastewaters. Membranes are predominantly polymer-based and despite steady advances in polymeric materials, they continue to suffer from operational problems including biofouling and breakages. This work addresses these two disparate problems by developing novel CNT-polymer nanocomposite materials that contain variously functionalized carbon nanotubes (fCNTs) in low quantities (<0.5wt%). Several strategies have been employed to achieve highly functional CNT-polymer nanocomposite membranes including blend mixing, ionic charge association, and covalent cross-linking with monomer and oligomer constituents. These CNT-polymer nanocomposite membranes were compared to traditional polymer membranes across various properties including increased Young's Modulus, changes in surface hydrophilicity, fine control over molecular weight cut-off and flux, and surface electrical conductivity. Membranes with high surface electrical conductivity were further tested for their anti-biofouling properties. Finally, CNT stability and polymer compatibility were evaluated throughout membrane manufacture, use, and cleaning. The incorporation of CNTs mixed in bulk phase and linked through ionic associations in polymer matrices showed significant (50%) increases in Young's modulus for certain CNT functionalizations and derivatization percent. Membranes formed with high surface electrical conductivity demonstrated almost complete resistance to biofouling (> 95%) in long-term bacterially challenged experiments. CNTs and polymer mixtures that lacked covalent or ionic bonds were susceptible to significant (up to 10%) loss of CNTs during membrane non-solvent gelation and aggressive chemical cleaning treatment. Functionalized carbon nanotubes endow polymer membranes with their unique strength and electrically conductive properties. These added properties were demonstrated to greatly

  9. Advanced computer techniques for inverse modeling of electric current in cardiac tissue

    SciTech Connect

    Hutchinson, S.A.; Romero, L.A.; Diegert, C.F.

    1996-08-01

    For many years, ECG`s and vector cardiograms have been the tools of choice for non-invasive diagnosis of cardiac conduction problems, such as found in reentrant tachycardia or Wolff-Parkinson-White (WPW) syndrome. Through skillful analysis of these skin-surface measurements of cardiac generated electric currents, a physician can deduce the general location of heart conduction irregularities. Using a combination of high-fidelity geometry modeling, advanced mathematical algorithms and massively parallel computing, Sandia`s approach would provide much more accurate information and thus allow the physician to pinpoint the source of an arrhythmia or abnormal conduction pathway.

  10. Closing the Energy Budget: Advances in assessing heat fluxes into shallow lakes and ponds (Invited)

    NASA Astrophysics Data System (ADS)

    Tyler, S. W.; Hausner, M. B.; Suarez, F. I.; Selker, J. S.

    2009-12-01

    While soil heat flux is traditionally directly measured in any land surface energy study, measuring heat flux into and out of lakes and ponds is complicated by water column mixing processes, differing radiation adsorption coefficients, turbidity variation and heat flux through the sediment-water interface. High resolution thermal profile, to assess heat storage changes in aquatic systems is both time consuming and challenging using traditional thermister or thermocouple strings or casts. Recent advances in Raman spectra distributed temperature sensing (DTS) offer the opportunity to measure, at high spatial and temporal resolution, the thermal storage changes occurring in lakes and ponds. Measurements of thermal storage using DTS are presented from two distinct environments; a strongly density stratified solar pond and a deep cavern system (Devils Hole in Death Valley National Park), demonstrating the effectiveness of high resolution temperature measurements. In the solar pond environment, closure of the energy budget using direct measurements of evaporation and net radiation was greatly improved by incorporating transient thermal measurements, and the development of a cooling boundary layer easily shown. At Devils Hole, variations in shading of the water surface produced small but measureable horizontal gradients in water column temperature for short periods of the day, which impact both pool evaporation and the metabolism and behavior of aquatic organisms

  11. An advanced model of heat and mass transfer in the protective clothing - verification

    NASA Astrophysics Data System (ADS)

    Łapka, P.; Furmański, P.

    2016-09-01

    The paper presents an advanced mathematical and numerical models of heat and mass transfer in the multi-layers protective clothing and in elements of the experimental stand subjected to either high surroundings temperature or high radiative heat flux emitted by hot objects. The model included conductive-radiative heat transfer in the hygroscopic porous fabrics and air gaps as well as conductive heat transfer in components of the stand. Additionally, water vapour diffusion in the pores and air spaces as well as phase transition of the bound water in the fabric fibres (sorption and desorption) were accounted for. The thermal radiation was treated in the rigorous way e.g.: semi-transparent absorbing, emitting and scattering fabrics were assumed a non-grey and all optical phenomena at internal or external walls were modelled. The air was assumed transparent. Complex energy and mass balance as well as optical conditions at internal or external interfaces were formulated in order to find exact values of temperatures, vapour densities and radiation intensities at these interfaces. The obtained highly non-linear coupled system of discrete equation was solve by the in-house iterative algorithm which was based on the Finite Volume Method. The model was then successfully partially verified against the results obtained from commercial software for simplified cases.

  12. Progress on advanced dc and ac induction drives for electric vehicles

    NASA Technical Reports Server (NTRS)

    Schwartz, H. J.

    1982-01-01

    Progress is reported in the development of complete electric vehicle propulsion systems, and the results of tests on the Road Load Simulator of two such systems representative of advanced dc and ac drive technology are presented. One is the system used in the DOE's ETV-1 integrated test vehicle which consists of a shunt wound dc traction motor under microprocessor control using a transistorized controller. The motor drives the vehicle through a fixed ratio transmission. The second system uses an ac induction motor controlled by transistorized pulse width modulated inverter which drives through a two speed automatically shifted transmission. The inverter and transmission both operate under the control of a microprocessor. The characteristics of these systems are also compared with the propulsion system technology available in vehicles being manufactured at the inception of the DOE program and with an advanced, highly integrated propulsion system upon which technology development was recently initiated.

  13. Advanced launch system (ALS) - Electrical actuation and power systems improve operability and cost picture

    NASA Technical Reports Server (NTRS)

    Sundberg, Gale R.

    1990-01-01

    To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrrical power system and controls for all aviation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a sdpecific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military ans civilian aircraft, lunar/Martian vehicles, and a multitude of comercial applications.

  14. Modeling of lung's electrical impedance using fractional calculus for analysis of heat generation during RF-ablation.

    PubMed

    Yamazaki, Nozomu; Kobayashi, Yo; Kikuchi, Hayato; Isobe, Yosuke; Lu, XiaoWei; Miyashita, Tomoyuki; Fujie, Masakatsu G

    2014-01-01

    Recently, Radio Frequency Ablation (RFA) is becoming a popular therapy for various cancers such as liver, breast, or lung cancer. RFA is one kinds of thermal therapy. However, it has been often reported about excessive ablation or non-ablation due to difficult control of ablation energy. In order to solve these difficulties, we have been proposed robotized RF-ablation system for precise cancer treatment. We have been tried to control heat energy by control of electromagnetic-wave frequency. In this paper, we reported about relation among electrical impedance of lung, lung's internal air volumes, and heat energy by use of electromagnetic-wave. In case of RFA for lung cancer, heat energy depends on electrical impedance and lung's internal air volumes. Electrical impedance has the dependence of electromagnetic-wave frequency and the dependence of lung's internal air volumes. Therefore, firstly we considered about fractional calculus model between lung's internal air volumes and electrical impedance. Secondly, we measured electric impedance frequency characteristic of lung with change of lung's internal air volumes. The measured and modeled results showed that use of fractional calculus realized high accurate model for electrical impedance of lung. And, from the results of numerical analysis of heat energy, it is supposed that control of electromagnetic-wave frequency has a small effectiveness for lung tissue ablation even if lung includes abundant air.

  15. Advanced design nuclear power plants: Competitive, economical electricity. An analysis of the cost of electricity from coal, gas and nuclear power plants

    SciTech Connect

    Not Available

    1992-06-01

    This report presents an updated analysis of the projected cost of electricity from new baseload power plants beginning operation around the year 2000. Included in the study are: (1) advanced-design, standardized nuclear power plants; (2) low emissions coal-fired power plants; (3) gasified coal-fired power plants; and (4) natural gas-fired power plants. This analysis shows that electricity from advanced-design, standardized nuclear power plants will be economically competitive with all other baseload electric generating system alternatives. This does not mean that any one source of electric power is always preferable to another. Rather, what this analysis indicates is that, as utilities and others begin planning for future baseload power plants, advanced-design nuclear plants should be considered an economically viable option to be included in their detailed studies of alternatives. Even with aggressive and successful conservation, efficiency and demand-side management programs, some new baseload electric supply will be needed during the 1990s and into the future. The baseload generating plants required in the 1990s are currently being designed and constructed. For those required shortly after 2000, the planning and alternatives assessment process must start now. It takes up to ten years to plan, design, license and construct a new coal-fired or nuclear fueled baseload electric generating plant and about six years for a natural gas-fired plant. This study indicates that for 600-megawatt blocks of capacity, advanced-design nuclear plants could supply electricity at an average of 4.5 cents per kilowatt-hour versus 4.8 cents per kilowatt-hour for an advanced pulverized-coal plant, 5.0 cents per kilowatt-hour for a gasified-coal combined cycle plant, and 4.3 cents per kilowatt-hour for a gas-fired combined cycle combustion turbine plant.

  16. Production of general purpose heat source (GPHS) using advanced manufacturing methods

    NASA Astrophysics Data System (ADS)

    Miller, Roger G.

    1996-03-01

    Mankind will continue to explore the stars through the use of unmanned space craft until the technology and costs are compatible with sending travelers to the outer planets of our solar system and beyond. Unmanned probes of the present and future will be necessary to develop the necessary technologies and obtain information that will make this travel possible. Because of the significant costs incurred, the use of modern manufacturing technologies must be used to lower the investment needed even when shared by international partnerships. For over the last 30 years, radioisotopes have provided the heat from which electrical power is extracted. Electric power for future spacecraft will be provided by either Radioisotope Thermoelectric Generators (RTG), Radioisotopic Thermophotovoltaic systems (RTPV), radioisotope Stirling systems, or a combination of these. All of these systems will be thermally driven by General Purpose Heat Source (GPHS) fueled clad in some configuration. The GPHS clad contains a 238PuO2 pellet encapsulated in an iridium alloy container. Historically, the fabrication of the iridium alloy shells has been performed at EG&G Mound and Oak Ridge National Laboratory (ORNL), and girth welding at Westinghouse Savannah River Corporation (WSRC) and Los Alamos National Laboratory (LANL). This paper will describe the use of laser processing for welding, drilling, cutting, and machining with other manufacturing methods to reduce the costs of producing GPHS fueled clad components and compléted assemblies. Incorporation of new quality technologies will compliment these manufacturing methods to reduce cost.

  17. Local and transient structural changes in stratum corneum at high electric fields: contribution of Joule heating.

    PubMed

    Pliquett, U; Gallo, S; Hui, S W; Gusbeth, Ch; Neumann, E

    2005-09-01

    Electroporation of skin is accompanied by local heating, such that thermally induced structural changes of the stratum corneum (SC) accompany the field effect. Comparing on the time scale, the local changes in structure, temperature and conductance of the SC, during and after the pulse, it is seen that Joule heating also facilitates the subsequent molecular transport. It is found that the transport of medium-sized, ionic molecules occurs through localized transport regions (LTR). The size of a LTR increases with the pulse length, whereas the density of the LTRs increases with increasing voltage, for instance at U(SC=)80 V, the LTR cover approximately 0.02--1% of the surface area. The state of low resistance within the LTR is long-lived. During high voltage application, the center of the LTR is heated above the phase transition temperature of the SC lipids (70 degrees C) and the heat front propagates outwards. Inside the SC, the pulse causes aggregates of small-sized vesicles. At a higher temperature, the aggregate formation and their disappearance are delayed. Multiple pulses with the applied voltage of U(appl)=80 V induce the formation of long-lasting vesicle aggregates with a diameter of slashed circle=1--30 microm, covering 0.05--0.5% of the total sample area. The electric energy dissipated within the LTR during high voltage application is apparently sufficient to raise the temperature well above the phase transition temperature of the lipids of the SC, accounting for the conformational changes from the multi-lamella to the vesicular structures.

  18. Novel Direct Steelmaking by Combining Microwave, Electric Arc, and Exothermal Heating Technologies

    SciTech Connect

    Dr. Xiaodi Huang; Dr. J. Y. Hwang

    2005-03-28

    Steel is a basic material broadly used by perhaps every industry and individual. It is critical to our nation's economy and national security. Unfortunately, the American steel industry is losing competitiveness in the world steel production field. There is an urgent need to develop the next generation of steelmaking technology for the American steel industry. Direct steelmaking through the combination of microwave, electric arc, and exothermal heating is a revolutionary change from current steelmaking technology. This technology can produce molten steel directly from a shippable agglomerate, consisting of iron oxide fines, powdered coal, and ground limestone. This technology is projected to eliminate many current intermediate steelmaking steps including coking, pellet sintering, blast furnace (BF) ironmaking, and basic oxygen furnace (BOF) steelmaking. This technology has the potential to (a) save up to 45% of the energy consumed by conventional steelmaking; (b) dramatically reduce the emission of CO{sub 2}, SO{sub 2}, NO{sub x}, VOCs, fine particulates, and air toxics; (c) substantially reduce waste and emission control costs; (d) greatly lower capital cost; and (e) considerably reduce steel production costs. This technology is based on the unique capability of microwaves to rapidly heat steelmaking raw materials to elevated temperature, then rapidly reduce iron oxides to metal by volumetric heating. Microwave heating, augmented with electric arc and exothermal reactions, is capable of producing molten steel. This technology has the components necessary to establish the ''future'' domestic steel industry as a technology leader with a strong economically competitive position in world markets. The project goals were to assess the utilization of a new steelmaking technology for its potential to achieve better overall energy efficiency, minimize pollutants and wastes, lower capital and operating costs, and increase the competitiveness of the U.S. steel industry. The

  19. Low Cost Advanced Thermoelectric (TE) Technology for Automotive Waste Heat Recovery

    NASA Astrophysics Data System (ADS)

    Meisner, G. P.

    2014-03-01

    Low cost, fully integrated TE generators (TEGs) to recover waste heat from vehicle exhaust will reduce transportation sector energy consumption and emissions. TEGs will be the first application of high-temperature TE materials for high-volume use and establish new industrial sectors with scaled up production capability of TEG materials and components. We will create a potential supply chain for practical automotive TEGs and identify manufacturing and assembly processes for large scale production of TEG materials and components. Our work focusses on several innovative R&D paths: (1) enhanced TE material performance by doping and compositional tuning, (2) optimized TE material fabrication and processing to reduce thermal conductivity and improve fracture strength, (3) high volume production for successful skutterudite commercialization, (4) new material, nanostructure, and nanoscale approaches to reduce thermal interface and electrical contact resistances, (5) innovative heat exchangers for high efficiency heat flows and optimum temperature profiles despite highly variable exhaust gas operating conditions, (6) new modeling and simulation tools, and (7) inexpensive materials for thermal insulation and coatings for TE encapsulation. Recent results will be presented. Supported by the U.S. DOE Vehicle Technology Program.

  20. Effect of heat treatments on the tensile and electrical properties of high-strength, high-conductivity copper alloys

    SciTech Connect

    Zinkle, S.J.; Eatherly, W.S.

    1997-08-01

    The unirradiated tensile properties of CuCrZr produced by two different vendors have been measured following different heat treatments. Room temperature electrical resistivity measurements were also performed in order to estimate the thermal conductivity of these specimens. The thermomechanical conditions studied included solution quenched, solution quenched and aged (ITER reference heat treatment), simulated slow HIP thermal cycle ({approximately}1{degrees}C/min cooling from solutionizing temperature) and simulated fast HIP thermal cycle ({approximately}100{degrees}C/min cooling from solutionizing temperature). Specimens from the last two heat treatments were tested in both the solution-cooled condition and after subsequent precipitate aging at 475{degrees}C for 2 h. Both of the simulated HIP thermal cycles caused a pronounced decreases in the strength and electrical conductivity of CuCrZr. The tensile and electrical properties were unchanged by subsequent aging in the slow HIP thermal cycles caused a pronounced decrease in the strength and electrical conductivity of CuCrZr. The tensile and electrical properties were unchanged by subsequent aging in the slow HIP thermal cycle specimens, whereas the strength and conductivity following aging in the fast HIP thermal cycle improved to {approximately}65% of the solution quenched and aged CuCrZr values. Limited tensile and electrical resistivity measurements were also made on two new heats of Hycon 3HP CuNiBe. High strength but poor uniform and total elongations were observed at 500{degrees}C on one of these new heats of CuNiBe, similar to that observed in other heats.

  1. Recent Advances in Regional Climate System Modeling and ClimateChange Analyses of Extreme Heat

    SciTech Connect

    Miller, Norman L.

    2004-09-24

    During the period May 2003 to May 2004, there were two CEC/PIER funded primary research activities by the Atmosphere and Ocean Sciences Group/Earth Science Division at LBNL. These activities are the implementation and testing of the National Center for Atmospheric Research Community Land Model (CLM) into MM5, and the analysis of extreme heat days under a new set of climate simulations. The new version of MM5,MM5-CLM, has been tested for a 90 day snowmelt period in the northwestern U.S. Results show that this new code upgrade, as compared to the MM5-NOAH, has improved snowmelt, temperature, and precipitation when compared to observations. These are due in part to a subgrid scheme,advanced snow processes, and advanced vegetation. The climate change analysis is the upper and lower IPCC Special Report on Emission Scenarios, representing fossil fuel intensive and energy conserving future emission scenarios, and medium and low sensitivity Global Climate Models. Results indicate that California cities will see increases in the number of heat wave and temperature threshold days from two to six times.These results may be viewed as potential outcomes based on today's decisions on emissions.

  2. Electric power and the global economy: Advances in database construction and sector representation

    NASA Astrophysics Data System (ADS)

    Peters, Jeffrey C.

    The electricity sector plays a crucial role in the global economy. The sector is a major consumer of fossil fuel resources, producer of greenhouse gas emissions, and an important indicator and correlate of economic development. As such, the sector is a primary target for policy-makers seeking to address these issues. The sector is also experiencing rapid technological change in generation (e.g. renewables), primary inputs (e.g. horizontal drilling and hydraulic fracturing), and end-use efficiency. This dissertation seeks to further our understanding of the role of the electricity sector as part of the dynamic global energy-economy, which requires significant research advances in both database construction and modeling techniques. Chapter 2 identifies useful engineering-level data and presents a novel matrix balancing method for integrating these data in global economic databases. Chapter 3 demonstrates the relationship between matrix balancing method and modeling results, and Chapter 4 presents the full construction methodology for GTAP-Power, the foremost, publicly-available global computable general equilibrium database. Chapter 5 presents an electricity-detailed computational equilibrium model that explicitly and endogenously captures capacity utilization, capacity expansion, and their interdependency - important aspects of technological substitution in the electricity sector. The individual, but interrelated, research contributions to database construction and electricity modeling in computational equilibrium are placed in the context of analyzing the US EPA Clean Power Plan (CPP) CO 2 target of 32 percent reduction of CO2 emissions in the US electricity sector from a 2005 baseline by 2030. Assuming current fuel prices, the model predicts an almost 28 percent CO2 reduction without further policy intervention. Next, a carbon tax and investment subsidies for renewable technologies to meet the CPP full targets are imposed and compared (Chapter 6). The carbon tax

  3. Evaluation of non-thermal effects of electricity on ascorbic acid and carotenoid degradation in acerola pulp during ohmic heating.

    PubMed

    Jaeschke, Débora Pez; Marczak, Ligia Damasceno Ferreira; Mercali, Giovana Domeneghini

    2016-05-15

    The effect of electric field on ascorbic acid and carotenoid degradation in acerola pulp during ohmic heating was evaluated. Ascorbic acid kinetic degradation was evaluated at 80, 85, 90 and 95°C during 60 min of thermal treatment by ohmic and conventional heating. Carotenoid degradation was evaluated at 90 and 95°C after 50 min of treatment. The different temperatures evaluated showed the same effect on degradation rates. To investigate the influence of oxygen concentration on the degradation process, ohmic heating was also carried out under rich and poor oxygen modified atmospheres at 90°C. Ascorbic acid and carotenoid degradation was higher under a rich oxygen atmosphere, indicating that oxygen is the limiting reagent of the degradation reaction. Ascorbic acid and carotenoid degradation was similar for both heating technologies, demonstrating that the presence of the oscillating electric field did not influence the mechanisms and rates of reactions associated with the degradation process.

  4. Control and gating of kinesin-microtubule motility on electrically heated thermo-chips.

    PubMed

    Ramsey, Laurence; Schroeder, Viktor; van Zalinge, Harm; Berndt, Michael; Korten, Till; Diez, Stefan; Nicolau, Dan V

    2014-06-01

    First lab-on-chip devices based on active transport by biomolecular motors have been demonstrated for basic detection and sorting applications. However, to fully employ the advantages of such hybrid nanotechnology, versatile spatial and temporal control mechanisms are required. Using a thermo-responsive polymer, we demonstrated a temperature controlled gate that either allows or disallows the passing of microtubules through a topographically defined channel. The gate is addressed by a narrow gold wire, which acts as a local heating element. It is shown that the electrical current flowing through a narrow gold channel can control the local temperature and as a result the conformation of the polymer. This is the first demonstration of a spatially addressable gate for microtubule motility which is a key element of nanodevices based on biomolecular motors.

  5. Induced electric fields in workers near low-frequency induction heating machines.

    PubMed

    Kos, Bor; Valič, Blaž; Kotnik, Tadej; Gajšek, Peter

    2014-04-01

    Published data on occupational exposure to induction heating equipment are scarce, particularly in terms of induced quantities in the human body. This article provides some additional information by investigating exposure to two such machines-an induction furnace and an induction hardening machine. Additionally, a spatial averaging algorithm for measured fields we developed in a previous publication is tested on new data. The human model was positioned at distances where measured values of magnetic flux density were above the reference levels. All human exposure was below the basic restriction-the lower bound of the 0.1 top percentile induced electric field in the body of a worker was 0.193 V/m at 30 cm from the induction furnace.

  6. On-demand hydrogen generation using nanosilicon: splitting water without light, heat, or electricity.

    PubMed

    Erogbogbo, Folarin; Lin, Tao; Tucciarone, Phillip M; LaJoie, Krystal M; Lai, Larry; Patki, Gauri D; Prasad, Paras N; Swihart, Mark T

    2013-02-13

    We demonstrate that nanosize silicon (~10 nm diameter) reacts with water to generate hydrogen 1000 times faster than bulk silicon, 100 times faster than previously reported Si structures, and 6 times faster than competing metal formulations. The H(2) production rate using 10 nm Si is 150 times that obtained using 100 nm particles, dramatically exceeding the expected effect of increased surface to volume ratio. We attribute this to a change in the etching dynamics at the nanoscale from anisotropic etching of larger silicon to effectively isotropic etching of 10 nm silicon. These results imply that nanosilicon could provide a practical approach for on-demand hydrogen production without addition of heat, light, or electrical energy.

  7. Diagnosis of the heating effect on the electrical resistivity of Ouargla (Algeria) dunes sand using XRD patterns and FTIR spectra

    NASA Astrophysics Data System (ADS)

    Mechri, Mohammed Laïd; Chihi, Smaïl; Mahdadi, Naouia; Beddiaf, Samiha

    2017-01-01

    XRD patterns and FTIR spectra have shown that dunes sand of Ouargla's region, in its natural state, is formed of a high percentage of quartz, gypsum and very low percentage of kaolinite and hematite, in addition to some organic compounds. The electrical resistivity of the natural sand has been measured, it was 6 × 1014 Ω cm. Six samples of the sand were heated separately at 200, 400, 600, 800, 1000 and 1200 °C. The XRD patterns and FTIR spectra of these samples were carried out. On the other hand, the electrical resistivities of these samples have been measured. The change of the electrical resistivity with heat shows a nonlinear behavior. The heated sample of sand at 200 °C has lost some water. Most of the gypsum in the 200 °C heated sample has transformed into anhydrite, and the rest has transformed into bassanite, and its electrical resistivity has fallen down to 3.5 × 1014 Ω cm. By heating at 400 °C, the gypsum has lost all its water and it has transformed entirely to anhydrite, and its electrical resistivity became 6.75 × 1012 Ω cm, it has the lowest measured resistivity. At 600 °C and 800 °C, in addition to anhydrite, the kaolinite transformed to meta-kaolin due to the continuous breaking of OH bond and formation of water vapor, and the electrical resistivity increased to (1.5-1.9) × 1014 Ω cm. Heating at 1000 °C leads to the initiation of the interaction between anhydrite and quartz, the wollastonite appears, and the meta-kaolin transforms to aluminum-silicon and cristobalite. The wollastonite is a good electrical insulator. It raises the electrical resistivity of sand to 2.6 × 1014 Ω cm. The heating at 1200 °C makes all anhydrite to interact with quartz due to the increasing of volume of wollastonite, the anhydrite disappears completely, the quartz transforms into cristobalite. The cristobalite increases due to the dissociation of aluminium-silicon into mullite and cristobalite, as well as the transformation of quartz into cristobalite at

  8. An electrical-heating and self-sensing shape memory polymer composite incorporated with carbon fiber felt

    NASA Astrophysics Data System (ADS)

    Gong, Xiaobo; Liu, Liwu; Liu, Yanju; Leng, Jinsong

    2016-03-01

    Shape memory polymers (SMPs) have the ability to adjust their stiffness, lock a temporary shape, and recover the permanent shape upon imposing an appropriate stimulus. They have found their way into the field of morphing structures. The electrically Joule resistive heating of the conductive composite can be a desirable stimulus to activate the shape memory effect of SMPs without external heating equipment. Electro-induced SMP composites incorporated with carbon fiber felt (CFF) were explored in this work. The CFF is an excellent conductive filler which can easily spread throughout the composite. It has a huge advantage in terms of low cost, simple manufacturing process, and uniform and tunable temperature distribution while heating. A continuous and compact conductive network made of carbon fibers and the overlap joints among them was observed from the microscopy images, and this network contributes to the high conductive properties of the CFF/SMP composites. The CFF/SMP composites can be electrical-heated rapidly and uniformly, and its’ shape recovery effect can be actuated by the electrical resistance Joule heating of the CFF without an external heater. The CFF/SMP composite get higher modulus and higher strength than the pure SMP without losing any strain recovery property. The high dependence of temperature and strain on the electrical resistance also make the composite a good self-sensing material. In general, the CFF/SMP composite shows great prospects as a potential material for the future morphing structures.

  9. Emission of terahertz radiation from GaN/AlGaN heterostructure under electron heating in lateral electric field

    NASA Astrophysics Data System (ADS)

    Shalygin, V. A.; Vorobjev, L. E.; Firsov, D. A.; Sofronov, A. N.; Melentyev, G. A.; Lundin, W. V.; Sakharov, A. V.; Tsatsulnikov, A. F.

    2013-12-01

    Spontaneous emission of terahertz radiation from modulation-doped AlGaN/GaN heterostructure under conditions of heating of a two-dimensional electron gas in the lateral electric field has been studied. The experimental data on the field dependence of the integral intensity of THz emission is compared with the theoretical simulation of blackbody-like emission from hot 2D electrons. Complementary transport measurements have been carried out to determine the dependence of effective electron temperature on electric field.

  10. The mathematical models of electromagnetic field dynamics and heat transfer in closed electrical contacts including Thomson effect

    NASA Astrophysics Data System (ADS)

    Kharin, Stanislav; Sarsengeldin, Merey; Kassabek, Samat

    2016-08-01

    We represent mathematical models of electromagnetic field dynamics and heat transfer in closed symmetric and asymmetric electrical contacts including Thomson effect, which are essentially nonlinear due to the dependence of thermal and electrical conductivities on temperature. Suggested solutions are based on the assumption of identity of equipotentials and isothermal surfaces, which agrees with experimental data and valid for both linear and nonlinear cases. Well known Kohlrausch temperature-potential relation is analytically justified.

  11. Advances in the Lightweight Air-Liquid Composite Heat Exchanger Development for Space Exploration Applications

    NASA Technical Reports Server (NTRS)

    Shin, E. Eugene; Johnston, J. Chris; Haas, Daniel

    2011-01-01

    An advanced, lightweight composite modular Air/Liquid (A/L) Heat Exchanger (HX) Prototype for potential space exploration thermal management applications was successfully designed, manufactured, and tested. This full-scale Prototype consisting of 19 modules, based on recommendations from its predecessor Engineering Development unit (EDU) but with improved thermal characteristics and manufacturability, was 11.2 % lighter than the EDU and achieves potentially a 42.7% weight reduction from the existing state-of-the-art metallic HX demonstrator. However, its higher pressure drop (0.58 psid vs. 0.16 psid of the metal HX) has to be mitigated by foam material optimizations and design modifications including a more systematic air channel design. Scalability of the Prototype design was validated experimentally by comparing manufacturability and performance between the 2-module coupon and the 19-module Prototype. The Prototype utilized the thermally conductive open-cell carbon foam material but with lower density and adopted a novel high-efficiency cooling system with significantly increased heat transfer contact surface areas, improved fabricability and manufacturability compared to the EDU. Even though the Prototype was required to meet both the thermal and the structural specifications, accomplishing the thermal requirement was a higher priority goal for this first version. Overall, the Prototype outperformed both the EDU and the corresponding metal HX, particularly in terms of specific heat transfer, but achieved 93.4% of the target. The next generation Prototype to achieve the specification target, 3,450W would need 24 core modules based on the simple scaling factor. The scale-up Prototype will weigh about 14.7 Kg vs. 21.6 Kg for the metal counterpart. The advancement of this lightweight composite HX development from the original feasibility test coupons to EDU to Prototype is discussed in this paper.

  12. Heating of the solar middle chromosphere by large-scale electric currents

    NASA Technical Reports Server (NTRS)

    Goodman, M. L.

    1995-01-01

    A global resistive, two-dimensional, time-dependent magnetohydrodynamic (MHD) model is used to introduce and support the hypothesis that the quiet solar middle chromosphere is heated by resistive dissipation of large-scale electric currents which fill most of its volume. The scale height and maximum magnitude of the current density are 400 km and 31.3 m/sq m, respectively. The associated magnetic field is almost horizontal, has the same scale height as the current density, and has a maximum magnitude of 153 G. The current is carried by electrons flowing across magnetic field lines at 1 m/s. The resistivity is the electron contribution to the Pedersen resitivity for a weakly ionized, strongly magnetized, hydrogen gas. The model does not include a driving mechanism. Most of the physical quantities in the model decrease exponentially with time on a resistive timescale of 41.3 minutes. However, the initial values and spatial; dependence of these quantities are expected to be essentially the same as they would be if the correct driving mechanism were included in a more general model. The heating rate per unit mass is found to be 4.5 x 10(exp 9) ergs/g/s, independent of height and latitude. The electron density scale height is found to be 800 km. The model predicts that 90% of the thermal energy required to heat the middle chromosphere is deposited in the height range 300-760 km above the temperature minimum. It is shown to be consistent to assume that the radiation rate per unit volume is proportional to the magnetic energy density, and then it follows that the heating rate per unit volume is also proportional to the energy from the photosphere into the overlying chromosphere are briefly discussed as possible driving mechanisms for establishing and maintaining the current system. The case in which part of or all of the current is carried by protons and metal ions, and the contribution of electron-proton scattering to the current are also considered, with the conclusion

  13. A Thermally-Regenerative Ammonia-Based Flow Battery for Electrical Energy Recovery from Waste Heat.

    PubMed

    Zhu, Xiuping; Rahimi, Mohammad; Gorski, Christopher A; Logan, Bruce

    2016-04-21

    Large amounts of low-grade waste heat (temperatures <130 °C) are released during many industrial, geothermal, and solar-based processes. Using thermally-regenerative ammonia solutions, low-grade thermal energy can be converted to electricity in battery systems. To improve reactor efficiency, a compact, ammonia-based flow battery (AFB) was developed and tested at different solution concentrations, flow rates, cell pairs, and circuit connections. The AFB achieved a maximum power density of 45 W m(-2) (15 kW m(-3) ) and an energy density of 1260 Wh manolyte (-3) , with a thermal energy efficiency of 0.7 % (5 % relative to the Carnot efficiency). The power and energy densities of the AFB were greater than those previously reported for thermoelectrochemical and salinity-gradient technologies, and the voltage or current could be increased using stacked cells. These results demonstrated that an ammonia-based flow battery is a promising technology to convert low-grade thermal energy to electricity.

  14. Two-dimensional steady-state analysis of an electrically heated thermionic fuel element

    SciTech Connect

    Huimin Xue; El-Genk, M.S.; Paramonov, D. )

    1993-01-20

    A two-dimensional transient model of a single cell, long Thermionic Fuel Element (TFE) is developed and its predictions are compared with published calculations and experimental data on steady-state operation of electrically heated, TOPAZ-II type TFEs. The operation parameters of the TFE, such as axial distributions of the emitter temperature, emission current density, and the electrode voltage are calculated and discussed. Results show that despite the excellent agreement between the model predictions of the axial distribution of the emitter temperature, its predictions of the maximum emission current density was lower by about 17%. This difference is attributed primarily to the J-V characteristics in the model, which could be different than those of the TOPAZ-II TFE, hence additional data on the latter is needed. When compared with experimental data, the model predictions of the electric power output are in excellent agreement with the data at thermal power input of 3.5 kW or higher, but within 10% of the data at lower thermal power.

  15. Measurements and Electrical Equivalent Model of Polymer PTC as a Function of Joule Heating Energy

    NASA Astrophysics Data System (ADS)

    Abubaker, Zawam; Maeyama, Mitsuaki

    In this paper, experiments were conducted to study the electrical I-V characteristics of the polymer Positive Temperature Coefficient (PTC)resistor as a function of joule heating due to I2R. More than 80short-circuit tests were carried out on four samples (rated 60V/40A), and the results show that all PTC samples tripped when the thresholdinput energy nearly equaled 20 J. We propose a new mathematical modelfor the PTC in the fault current condition, a PTC-TACS (Transient Analysis of Control Systems) model, by using the Electro-Magnetic Transient Program (EMTP), which is a function of the input joule heatingenergy. A comparison between the experimental results and EMTPsimulation results has shown that the PTC-TACS model is valid and veryeffective to investigate the PTC under fault current conditions inelectrical circuits and to design an over-current limiter based on PTCmaterials for industrial applications. In the discussion about radiationpower loss in case that the applied voltage is greater than 50V or thetripped time is less than 4ms, it is shown that the radiation powerloss can be neglected and the PTC resistance can be expressed only bythe input joule heating energy.

  16. Observation of Ion Cyclotron Heating in a Fast-flowing Plasma for an Advanced Plasma Thruster

    NASA Astrophysics Data System (ADS)

    Ando, Akira; Hatanaka, Motoi; Shibata, Masaki; Tobari, Hiroyuki; Hattori, Kunihiko; Inutake, Masaaki

    2004-11-01

    In the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) project in NASA, the combined system of the ion cyclotron heating and the magnetic nozzle is proposed to control a ratio of specific impulse to thrust at constant power. In order to establish the advanced plasma thruster, experiments of an ion heating and plasma acceleration by a magnetic nozzle are performed in a fast-flowing plasma in the HITOP device. A fast-flowing He plasma is produced by Magneto-Plasma-Dynamic Arcjet (MPDA) operated with an externally-applied magnetic field up to 1kG. RF waves with an ion cyclotron range of frequency (f=20-300kHz) is excited by a helically-wound antenna located downstream of the MPDA. Increases of an ion temperature and plasma stored energy measured by a diamagnetic coil clearly observed during the RF pulse. The heating efficiency is compared for various magnetic field configurations and strengths. There appears no indication of cyclotron resonance in a high density plasma where the ratio of ion cyclotron frequency to ion-ion collision one is below unity, because an ion-ion collisional effect is dominant. When the density becomes low and the ratio of ion cyclotron frequency to ion-ion collision one becomes high, features of ion cyclotron resonance are clearly appeared. The optimum magnetic field strength for the ion heating is slightly lower than that of the cyclotron resonance, which is caused by the Doppler effect due to the fast-flowing plasma. An ion energy distribution function is measured at a magnetic nozzle region by an electrostatic analyzer and increase of the parallel velocity is also observed.

  17. Evaluation of the need for emergency heat exchangers for long term emergency cooling of the Advanced Neutron Source Reactor

    SciTech Connect

    Khayat, M.I.; Anderson, J.L.; Battle, R.E.; March-Leuba, J.

    1994-05-01

    This report summarizes the work performed to evaluate the heat transferred to the light water pools from the primary piping system for the Advanced Neutron Source reactor (ANSR) conceptual design. It has been determined that the ANSR primary piping system will remove sufficient heat from the primary coolant system to the pools for certain design basis event accidents without the emergency heat exchangers if the design parameters, such as pool volumes and pipe sizes (length and surface area), are selected appropriately. Based on this analysis, the emergency heat exchangers might be removed, and their function can be performed by the primary piping passing through the light water pools described in the conceptual design report. This study also shows that connecting the pipe chase pool and the heat exchanger pools improve performance for ANSR emergency heat removal.

  18. Advanced heat-pipe heat exchanger and microprocessor-based modulating burner controls development. Final report, January 1985-December 1987

    SciTech Connect

    Lowenstein, A.; Cohen, B.; Feldman, S.; Marsala, J.; Spatz, M.

    1988-02-01

    The work presented in the report includes: (1) the development of a heat-pipe condensing heat exchanger; (2) the development of a nominal 100,000-Btu/hr modulating air/gas valve; (3) the experimental performance studies of water/copper thermosyphons; (4) the field operation of a six-zone warm-air heating system; (5) the adaptation of a conventional venturi-type burner to modulation; and (6) the results of a one-day workshop for manufacturers of HVAC equipment on heat-pipe heat exchangers. Several of the accomplishments of the project included: A unique air/gas valve was adapted to furnaces with heat-pipe and drum-type heat exchangers, providing these furnaces with over a 5-to-1 turndown capability. A six-zone warm-air heating system was tested for two winters with the modulating furnaces previously described. A data base for the application of copper/water thermosyphons was started. A ten-tube heat-pipe heat exchanger was incorporated into a conventional clam-shell furnace as its second-stage condensing heat exchanger with only a small increase in the furnace's dimensions.

  19. Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

    SciTech Connect

    Williams, R.M.; Jeffries-Nakamura, B.; Underwood, M.L.; Ryan, M.A.; O'Connor, D.; Kikkert, S.

    1991-01-01

    Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of the alkali metal, and low electrical resistance, other high temperature components of the cell face equally demanding requirements. The beta{double prime} alumina solid electrolyte (BASE), the seal between the BASE ceramic and its metallic transition to the hot alkali metal (liquid or vapor) source, and metallic components of the device are exposed to hot liquid alkali metal. Modification of AMTEC components may also be useful in optimizing the device for particular operating conditions. In particular, a potassium AMTEC may be expected to operate more efficiently at lower temperatures.

  20. Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

    SciTech Connect

    Williams, R.M.; Jeffries-Nakamura, B.; Underwood, M.L.; Ryan, M.A.; O`Connor, D.; Kikkert, S.

    1991-12-31

    Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of the alkali metal, and low electrical resistance, other high temperature components of the cell face equally demanding requirements. The beta{double_prime} alumina solid electrolyte (BASE), the seal between the BASE ceramic and its metallic transition to the hot alkali metal (liquid or vapor) source, and metallic components of the device are exposed to hot liquid alkali metal. Modification of AMTEC components may also be useful in optimizing the device for particular operating conditions. In particular, a potassium AMTEC may be expected to operate more efficiently at lower temperatures.

  1. Hawaiian Electric Advanced Inverter Grid Support Function Laboratory Validation and Analysis

    SciTech Connect

    Nelson, Austin; Nagarajan, Adarsh; Prabakar, Kumar; Gevorgian, Vahan; Lundstrom, Blake; Nepal, Shaili; Hoke, Anderson; Asano, Marc; Ueda, Reid; Shindo, Jon; Kubojiri, Kandice; Ceria, Riley; Ifuku, Earle

    2016-12-01

    The objective for this test plan was to better understand how to utilize the performance capabilities of advanced inverter functions to allow the interconnection of distributed energy resource (DER) systems to support the new Customer Self-Supply, Customer Grid-Supply, and other future DER programs. The purpose of this project was: 1) to characterize how the tested grid supportive inverters performed the functions of interest, 2) to evaluate the grid supportive inverters in an environment that emulates the dynamics of O'ahu's electrical distribution system, and 3) to gain insight into the benefits of the grid support functions on selected O'ahu island distribution feeders. These goals were achieved through laboratory testing of photovoltaic inverters, including power hardware-in-the-loop testing.

  2. On the physical interconnection of Seismic Electric Signals with seismicity: Recent advances

    NASA Astrophysics Data System (ADS)

    Sarlis, Nicholas; Skordas, Efthimios; Lazaridou, Mary; Varotsos, Panayiotis

    2013-04-01

    We review the recent advances on Seismic Electric Signals (SES) which are low frequency (˜ 1Hz) signals that precede earthquakes [1-3]. Since the 1980's Varotsos and Alexopoulos proposed [4] that SES are generated in the future focal area when the stress reaches a critical value, thus causing a cooperative orientation of the electric dipoles that anyhow exist in the focal area due to lattice imperfections in the ionic constituents of the rocks. A series of such signals within a short time are termed SES activity [5] and usually appear before major earthquakes. The combination of their physical properties enable the determination of the epicentral region and the magnitude well in advance. Natural time analysis introduced a decade ago [6, 7] may uncover novel dynamic features hidden behind time series in complex systems [8]. By employing this analysis, several advances have been made towards a better understanding of the SES properties. For example, it has been found [6, 8] that the natural time analysis of the seismicity subsequent to the initiation of a SES activity enables the determination of the occurrence time of an impending major mainshock within a time window of around one week. On this basis, predictions -including the magnitude, epicenter and time window of the expected event- have been documented well in advance for all five mainshocks with M_w×6.4 in Greece since 2001 [8, 9]. In addition, by applying natural time analysis to the time series of earthquakes, we recently found [10] that the order parameter of seismicity exhibits a unique change approximately at the date at which SES activities have been reported to initiate. This is the first time that before the occurrence of major earthquakes, anomalous changes are found to appear almost simultaneously in two different geophysical observables. 1. P. Varotsos and K. Alexopoulos, Tectonophysics 110, 73-98, 1984a. 2. P. Varotsos and K. Alexopoulos, Tectonophysics 110, 99-125, 1984b. 3. P.A. Varotsos, N

  3. Enhancement of Pool Boiling Heat Transfer and Control of Bubble Motion in Microgravity Using Electric Fields (BCOEL)

    NASA Technical Reports Server (NTRS)

    Herman, Cila; Iacona, Estelle; Acquaviva, Tom; Coho, Bill; Grant, Nechelle; Nahra, Henry; Taylor, Al; Julian, Ed; Robinson, Dale; VanZandt, Dave

    2001-01-01

    The BCOEL project focuses on improving pool boiling heat transfer and bubble control in microgravity by exposing the fluid to electric fields. The electric fields induce a body force that can replace gravity in the low gravity environment, and enhance bubble removal from the heated surface. A better understanding of microgravity effects on boiling with and without electric fields is critical to the proper design of the phase-change-heat-removal equipment for use in spacebased applications. The microgravity experiments will focus on the visualization of bubble formation and shape during boiling. Heat fluxes on the boiling surface will be measured, and, together with the measured driving temperature differences, used to plot boiling curves for different electric field magnitudes. Bubble formation and boiling processes were found to be extremely sensitive to g-jitter. The duration of the experimental run is critical in order to achieve steady state in microgravity experiments. The International Space Station provides conditions suitable for such experiments. The experimental apparatus to be used in the study is described in the paper. The apparatus will be tested in the KC-135 first, and microgravity experiments will be conducted on board of the International Space Station using the Microgravity Science Glovebox as the experimental platform.

  4. Vocational-Technical Physics Project. Thermometers: I. Temperature and Heat, II. Expansion Thermometers, III. Electrical Thermometers. Field Test Edition.

    ERIC Educational Resources Information Center

    Forsyth Technical Inst., Winston-Salem, NC.

    This vocational physics individualized student instructional module on thermometers consists of the three units: Temperature and heat, expansion thermometers, and electrical thermometers. Designed with a laboratory orientation, experiments are included on linear expansion; making a bimetallic thermometer, a liquid-in-gas thermometer, and a gas…

  5. Enhancement of Pool Boiling Heat Transfer and Control of Bubble Motion in Microgravity Using Electric Fields - BCOEL

    NASA Technical Reports Server (NTRS)

    Herman, Cila; Iacona, Estelle; Acquaviva, Tom; Coho, Bill; Grant, Nechelle; Nahra, Henry; Sankaran, Subramanian; Taylor, Al; Julian, Ed; Robinson, Dale; VanZandt, Dave

    2001-01-01

    The BCOEL project focuses on improving pool boiling heat transfer and bubble control in microgravity by exposing the fluid to electric fields. The electric fields induce a body force that can replace gravity in the low gravity environment, and enhance bubble removal from thc heated surface. A better understanding of microgravity effects on boiling with and without electric fields is critical to the proper design of the phase-change-heat-removal equipment for use in space-based applications. The microgravity experiments will focus on the visualization of bubble formation and shape during boiling. Heat fluxes on the boiling surface will be measured, and, together with the measured driving temperature differences, used to plot boiling curvcs for different electric field magnitudes. Bubble formation and boiling processes were found to be extremely sensitive to g-jitter. The duration of the experimental run is critical in order to achieve steady state in microgravity experiments. The International Space Station provides conditions suitable for such experiments. The experimental appararus to be used in the study is described in the paper. The apparatus will be tested in the KC-135 first, and microgravity experiments will be conducted on board of the International Space Station using the Microgravity Science Glovebox as the experimental platform.

  6. High temperature setup for measurements of Seebeck coefficient and electrical resistivity of thin films using inductive heating

    NASA Astrophysics Data System (ADS)

    Adnane, L.; Williams, N.; Silva, H.; Gokirmak, A.

    2015-10-01

    We have developed an automated setup for simultaneous measurement of Seebeck coefficient S(T) and electrical resistivity ρ(T) of thin film samples from room temperature to ˜650 °C. S and ρ are extracted from current-voltage (I-V) measurements obtained using a semiconductor parameter analyzer and temperature measurements obtained using commercial thermocouples. The slope and the x-axis intercept of the I-V characteristics represent the sample conductance G and the Seebeck voltage, respectively. The measured G(T) can be scaled to ρ(T) by the geometry factor obtained from the room temperature resistivity measurement of the film. The setup uses resistive or inductive heating to control the temperature and temperature gradient on the sample. Inductive heating is achieved with steel plates that surround the test area and a water cooled copper pipe coil underneath that generates an AC magnetic field. The measurements can be performed using resistive heating only or inductive heating only, or a combination of both depending on the desired heating ranges. Inductive heating provides a more uniform heating of the test area, does not require contacts to the sample holder, can be used up to the Curie temperature of the particular magnetic material, and the temperature gradients can be adjusted by the relative positions of the coil and sample. Example results obtained for low doped single-crystal silicon with inductive heating only and with resistive heating only are presented.

  7. Effects of temperature dependence of electrical and thermal conductivities on the heating of a one dimensional conductor

    NASA Astrophysics Data System (ADS)

    Antoulinakis, Foivos; Zhang, Peng; Lau, Y. Y.; Chernin, David

    2016-10-01

    Dependence of electrical conductivity on temperature gives rise to electrotheramal instability, an important instability for Z-pinches. In other areas, ohmic heating limits the operation of nanoscale circuits such as graphene electronics, carbon nanofiber based field emitters, and nanolasers. For many applications, it is important to consider the temperature dependence of the thermal and electrical conductivities when calculating the effects of ohmic heating. We examine the effects of linear temperature dependence of the electrical and thermal conductivities on the heating of a one-dimensional conductor by solving the coupled non-linear steady state electrical and thermal conduction equations. We find that there are conditions under which no steady state solution exists. In the special case in which the temperature dependence of the electrical conductivity may be neglected, we have obtained explicit expressions for these conditions. The maximum temperature and its location within the conductor are examined for various boundary conditions. We note that the absence of a steady state solution may indicate the possibility of thermal runaway. Work supported by AFOSR No. FA9550-14-1-0309, and by L-3 Communications.

  8. Investigation of austenitic alloys for advanced heat recovery and hot gas cleanup systems

    SciTech Connect

    Swindeman, R.W.; Ren, W.

    1996-08-01

    Materials properties were collected for the design and construction of structural components for use in advanced heat recovery and hot gas cleanup systems. Alloys systems included 9Cr-1Mo-V steel, modified 316 stainless steel, modified type 310 stainless steel, modified 20Cr-25Ni-Nb stainless steel, modified alloy 800, and two sulfidation resistant alloys: HR160 and HR120. Experimental work was undertaken to expand the databases for potentially useful alloys. Types of testing included creep, stress-rupture, creep-crack growth, fatigue, and post-exposure short-time tensile tests. Because of the interest in relatively inexpensive alloys for service at 700{degrees}C and higher, research emphasis was placed on a modified type 310 stainless steel and a modified 20Cr-25Ni-Nb stainless steel. Both steels were found to have useful strength to 925{degrees}C with good weldability and ductility.

  9. Investigation of austenitic alloys for advanced heat recovery and hot gas cleanup systems

    SciTech Connect

    Swindeman, R.W.; Ren, W.

    1995-08-01

    Alloys for design and construction of structural components needed to contain process streams and provide internal structures in advanced heat recovery and hot gas cleanup systems were examined. Emphasis was placed on high-strength, corrosion-resistant alloys for service at temperatures above 1000 {degrees}F (540{degrees}C). Data were collected that related to fabrication, joining, corrosion protection, and failure criteria. Alloys systems include modified type 310 and 20Cr-25Ni-Nb steels and sulfidation-resistance alloys HR120 and HR160. Types of testing include creep, stress-rupture, creep crack growth, fatigue, and post-exposure short-time tensile. Because of the interest in relatively inexpensive alloys for high temperature service, a modified type 310 stainless steel was developed with a target strength of twice that for standard type 310 stainless steel.

  10. Investigation of austenitic alloys for advanced heat recovery and hot-gas cleanup systems

    SciTech Connect

    Swindeman, R.W.

    1997-12-01

    Materials properties were collected for the design and construction of structural components for use in advanced heat recovery and hot gas cleanup systems. Alloys systems included 9Cr-1Mo-V steel, modified 316 stainless steel, modified type 310 stainless steel, modified 20Cr-25Ni-Nb stainless steel, and modified alloy 800. Experimental work was undertaken to expand the databases for potentially useful alloys. Types of testing included creep, stress-rupture, creep-crack growth, fatigue, and post-exposure short-time tensile tests. Because of the interest in relatively inexpensive alloys for service at 700 C and higher, research emphasis was placed on a modified type 310 stainless steel and a modified 20Cr-25Ni-Nb stainless steel. Both steels were found to have useful strength to 925 C with good weldability and ductility.

  11. Integration of Americium Heat Source into the Advanced Stirling Radioisotope Generator

    NASA Astrophysics Data System (ADS)

    Schulze, Erich; Quinn, Richard

    2014-08-01

    The Lockheed Martin developed Advanced Stirling Radioisotope Generator (ASRG) design uses similar technology as proposed for the European Space Agency (ESA) Radioisotope Power System (RPS) development program but different isotopes. The RPS uses americium, 241Am isotope, while the ASRG uses plutonium, 238Pu isotope. The 238Pu isotope provides four times greater thermal output per kilogram than the 241Am isotope. Lockheed Martin performed an internally funded feasibility assessment that determined integration of a 241Am fueled heat source into the ASRG is achievable with no changes to ASRG technology and only structural and volumetric design considerations required. Lockheed Martin is interested in developing collaborative partnerships with the United Kingdom (UK) for the ESA RPS development program.

  12. Heat, electricity, or transportation? The optimal use of residual and waste biomass in Europe from an environmental perspective.

    PubMed

    Steubing, Bernhard; Zah, Rainer; Ludwig, Christian

    2012-01-03

    The optimal use of forest energy wood, industrial wood residues, waste wood, agricultural residues, animal manure, biowaste, and sewage sludge in 2010 and 2030 was assessed for Europe. An energy system model was developed comprising 13 principal fossil technologies for the production of heat, electricity, and transport and 173 bioenergy conversion routes. The net environmental benefits of substituting fossil energy with bioenergy were calculated for all approximately 1500 combinations based on life cycle assessment (LCA) results. An optimization model determines the best use of biomass for different environmental indicators within the quantified EU-27 context of biomass availability and fossil energy utilization. Key factors determining the optimal use of biomass are the conversion efficiencies of bioenergy technologies and the kind and quantity of fossil energy technologies that can be substituted. Provided that heat can be used efficiently, optimizations for different environmental indicators almost always indicate that woody biomass is best used for combined heat and power generation, if coal, oil, or fuel oil based technologies can be substituted. The benefits of its conversion to SNG or ethanol are significantly lower. For non-woody biomass electricity generation, transportation, and heating yield almost comparable benefits as long as high conversion efficiencies and optimal substitutions are assured. The shares of fossil heat, electricity, and transportation that could be replaced with bioenergy are also provided.

  13. The effects of regional insolation differences upon advanced solar thermal electric power plant performance and energy costs

    NASA Technical Reports Server (NTRS)

    Latta, A. F.; Bowyer, J. M.; Fujita, T.

    1979-01-01

    This paper presents the performance and cost of four 10-MWe advanced solar thermal electric power plants sited in various regions of the continental United States. Each region has different insolation characteristics which result in varying collector field areas, plant performance, capital costs, and energy costs. The paraboloidal dish, central receiver, cylindrical parabolic trough, and compound parabolic concentrator (CPC) comprise the advanced concepts studied. This paper contains a discussion of the regional insolation data base, a description of the solar systems' performances and costs, and a presentation of a range for the forecast cost of conventional electricity by region and nationally over the next several decades.

  14. Electrical lysis: dynamics revisited and advances in On-chip operation.

    PubMed

    Morshed, Bashir; Shams, Maitham; Mussivand, Tofy

    2013-01-01

    Electrical lysis (EL) is the process of breaking the cell membrane to expose the internal contents under an applied high electric field. Lysis is an important phenomenon for cellular analysis, medical treatment, and biofouling control. This paper aims to review, summarize, and analyze recent advancements on EL. Major databases including PubMed, Ei Engineering Village, IEEE Xplore, and Scholars Portal were searched using relevant keywords. More than 50 articles published in English since 1997 are cited in this article. EL has several key advantages compared to other lysis techniques such as chemical, mechanical, sonication, or laser, including rapid speed of operation, ability to control, miniaturization, low cost, and low power requirement. A variety of cell types have been investigated for including protoplasts, E. coli, yeasts, blood cells, and cancer cells. EL has been developed and applied for decontamination, cytology, genetics, single-cell analysis, cancer treatment, and other applications. On-chip EL is a promising technology for multiplexed automated implementation of cell-sample preparation and processing with micro- or nanoliter reagents.

  15. Advanced single permanent magnet axipolar ironless stator ac motor for electric passenger vehicles

    NASA Technical Reports Server (NTRS)

    Beauchamp, E. D.; Hadfield, J. R.; Wuertz, K. L.

    1983-01-01

    A program was conducted to design and develop an advanced-concept motor specifically created for propulsion of electric vehicles with increased range, reduced energy consumption, and reduced life-cycle costs in comparison with conventional systems. The motor developed is a brushless, dc, rare-earth cobalt, permanent magnet, axial air gap inductor machine that uses an ironless stator. Air cooling is inherent provided by the centrifugal-fan action of the rotor poles. An extensive design phase was conducted, which included analysis of the system performance versus the SAE J227a(D) driving cycle. A proof-of-principle model was developed and tested, and a functional model was developed and tested. Full generator-level testing was conducted on the functional model, recording electromagnetic, thermal, aerodynamic, and acoustic noise data. The machine demonstrated 20.3 kW output at 1466 rad/s and 160 dc. The novel ironless stator demonstated the capability to continuously operate at peak current. The projected system performance based on the use of a transistor inverter is 23.6 kW output power at 1466 rad/s and 83.3 percent efficiency. Design areas of concern regarding electric vehicle applications include the inherently high windage loss and rotor inertia.

  16. Domestic olivine versus magnesite as a thermal energy storage material: Performance comparisons for electrically heated room-size units in accordance with ASHRAE standard 94.2

    NASA Astrophysics Data System (ADS)

    Laster, W. R.; Schoenhals, R. J.; Gay, B. M.; Palmour, H., III

    1982-05-01

    Electrically heated thermal energy storage (TES) heaters employing high heat capacity ceramic refractories for sensible heat storage have been in use in Europe for several years. With these heaters, low cost off peak electrical energy is stored by heating a storage core composed of ceramic material to approximately 800 C. During the peak period, no electrical energy is used as the building heating needs are supplied by extracting the stored heat from the core by forced air circulation. Recently significant interest in the use of off peak TES units in the US has occurred, leading to the search for a domestic supply of high heat capacity ceramic refractory material. North Carolina's extensive but under utilized supply of refractory grade olivine has been proposed as a source of storage material for these units. In this paper, the suitability of North Carolina olivine for heat storage applications is assessed by comparing its thermal performance with that of European materials.

  17. A randomised controlled trial of the electric heating pad vs forced-air warming for preventing hypothermia during laparotomy.

    PubMed

    Leung, K K; Lai, A; Wu, A

    2007-06-01

    A randomised controlled trial was conducted to compare the efficacy of upper body forced-air warming (Bair Hugger, Augustine Medical model 500/OR, Prairie, MN) with that of an electric heating pad (Operatherm 202, KanMed, Bromma, Sweden) for maintenance of intra-operative body temperature in 60 patients undergoing laparotomy under general anaesthesia. The nasopharyngeal temperature was recorded throughout the operative period. The mean (SD) final temperatures were 36.2 (0.4) degrees C with forced-air warming and 35.5 (1.0) degrees C with electric heating pad (p < 0.01). Upper body forced-air warming is more effective than the heating pad for maintenance of body temperature during laparotomy.

  18. Application of multi-model switching predictive functional control on the temperature system of an electric heating furnace.

    PubMed

    Xu, Weide; Zhang, Junfeng; Zhang, Ridong

    2017-02-06

    A method of multi-model switching based predictive functional control is proposed and applied to the temperature control system of an electric heating furnace. The control strategies provide the effective and independent control modes of the electric heating furnace temperature in order to obtain improved control performance. The method depends on conventional implementation of the multi-model switching state, which requires some endeavors to tune the switching model in the model predictive control and allows a reduction of the calculation compared with the weighted multiple model algorithms. In order to test the advantage of the proposed method, experimental equipment is set up and experiments are done on the temperature process of a heating furnace, which verify the validity and effectiveness of the proposed algorithm.

  19. Heat Transfer and Thermal Stability Research for Advanced Hydrocarbon Fuel Technologies

    NASA Technical Reports Server (NTRS)

    DeWitt, Kenneth; Stiegemeier, Benjamin

    2005-01-01

    In recent years there has been increased interest in the development of a new generation of high performance boost rocket engines. These efforts, which will represent a substantial advancement in boost engine technology over that developed for the Space Shuttle Main Engines in the early 1970s, are being pursued both at NASA and the United States Air Force. NASA, under its Space Launch Initiative s Next Generation Launch Technology Program, is investigating the feasibility of developing a highly reliable, long-life, liquid oxygen/kerosene (RP-1) rocket engine for launch vehicles. One of the top technical risks to any engine program employing hydrocarbon fuels is the potential for fuel thermal stability and material compatibility problems to occur under the high-pressure, high-temperature conditions required for regenerative fuel cooling of the engine combustion chamber and nozzle. Decreased heat transfer due to carbon deposits forming on wetted fuel components, corrosion of materials common in engine construction (copper based alloys), and corrosion induced pressure drop increases have all been observed in laboratory tests simulating rocket engine cooling channels. To mitigate these risks, the knowledge of how these fuels behave in high temperature environments must be obtained. Currently, due to the complexity of the physical and chemical process occurring, the only way to accomplish this is empirically. Heated tube testing is a well-established method of experimentally determining the thermal stability and heat transfer characteristics of hydrocarbon fuels. The popularity of this method stems from the low cost incurred in testing when compared to hot fire engine tests, the ability to have greater control over experimental conditions, and the accessibility of the test section, facilitating easy instrumentation. These benefits make heated tube testing the best alternative to hot fire engine testing for thermal stability and heat transfer research. This investigation

  20. Response to waste electrical and electronic equipments in China: legislation, recycling system, and advanced integrated process.

    PubMed

    Zhou, Lei; Xu, Zhenming

    2012-05-01

    Over the past 30 years, China has been suffering from negative environmental impacts from distempered waste electrical and electronic equipments (WEEE) recycling activities. For the purpose of environmental protection and resource reusing, China made a great effort to improve WEEE recycling. This article reviews progresses of three major fields in the development of China's WEEE recycling industry: legal system, formal recycling system, and advanced integrated process. Related laws concerning electronic waste (e-waste) management and renewable resource recycling are analyzed from aspects of improvements and loopholes. The outcomes and challenges for existing formal recycling systems are also discussed. The advantage and deficiency related to advanced integrated recycling processes for typical e-wastes are evaluated respectively. Finally, in order to achieve high disposal rates of WEEE, high-quantify separation of different materials in WEEE and high added value final products produced by separated materials from WEEE, an idea of integrated WEEE recycling system is proposed to point future development of WEEE recycling industry.

  1. Initial high-power testing of the ATF (Advanced Toroidal Facility) ECH (electron cyclotron heating) system

    SciTech Connect

    White, T.L.; Bigelow, T.S.; Kimrey, H.D. Jr.

    1987-01-01

    The Advanced Toroidal Facility (ATF) is a moderate aspect ratio torsatron that will utilize 53.2 GHz 200 kW Electron Cyclotron Heating (ECH) to produce nearly current-free target plasmas suitable for subsequent heating by strong neutral beam injection. The initial configuration of the ECH system from the gyrotron to ATF consists of an optical arc detector, three bellows, a waveguide mode analyzer, two TiO/sub 2/ mode absorbers, two 90/sup 0/ miter bends, two waveguide pumpouts, an insulating break, a gate valve, and miscellaneous straight waveguide sections feeding a launcher radiating in the TE/sub 02/ mode. Later, a focusing Vlasov launcher will be added to beam the ECH power to the saddle point in ATF magnetic geometry for optimum power deposition. The ECH system has several unique features; namely, the entire ECH system is evacuated, the ECH system is broadband, forward power is monitored by a newly developed waveguide mode analyzer, phase correcting miter bends will be employed, and the ECH system will be capable of operating short pulse to cw. Initial high-power tests show that the overall system efficiency is 87%. The waveguide mode analyzer shows that the gyrotron mode output consists of 13% TE/sub 01/, 82.6% TE/sub 02/, 2.5% TE/sub 03/, and 1.9% TE/sub 04/. 4 refs.

  2. Non-linear advanced control of the LHC inner triplet heat exchanger test unit

    NASA Astrophysics Data System (ADS)

    Viñuela, E. Blanco; Cubillos, J. Casas; de Prada Moraga, C.; Cristea, S.

    2002-05-01

    The future Large Hadron Collider (LHC) at CERN will include eight interaction region final focus magnet systems, the so-called "Inner Triplet," one on each side of the four beam collision points. The Inner Triplets will be cooled in a static bath of pressurized He II nominally at 1.9 K. This temperature is a control parameter and has very severe constraints in order to avoid the transition from the superconducting to normal resistive state. The main difference in these special zones with respect to a regular LHC cell is higher dynamic heat load unevenly distributed which modifies largely the process characteristics and hence the controller performance. Several control strategies have already been tested at CERN in a pilot plant (LHC String Test) which reproduced a LHC half-cell. In order to validate a common control structure along the whole LHC ring, a Nonlinear Model Predictive Control (NMPC) has been developed and implemented in the Inner Triplet Heat Exchanger Unit (IT-HXTU) at CERN. Automation of the Inner Triplet setup and the advanced control techniques deployed based on the Model Based Predictive Control (MBPC) principle are presented.

  3. Advanced development of the boundary element method for steady-state heat conduction

    NASA Technical Reports Server (NTRS)

    Dargush, G. F.; Banerjee, Prasanta K.

    1989-01-01

    Considerable progress has been made in recent years toward advancing the state-of-the-art in solid mechanics boundary element technology. In the present work, much of this new technology is applied in the development of a general-purpose boundary element method (BEM) for steady-state heat conduction. In particular, the BEM implementation involves the use of higher-order conforming elements, self-adaptive integration and multi-region capability. Two- and three-dimensional, as well as axisymmetric analysis, are incorporated within a unified framework. In addition, techniques are introduced for the calculation of boundary flux, and for the inclusion of thermal resistance across interfaces. As a final extension, an efficient formulation is developed for the analysis of solid three-dimensional bodies with embedded holes. For this last class of problems, the new BEM formulation is particularly attractive, since use of the alternatives (i.e. finite element or finite difference methods) is not practical. A number of detailed examples illustrate the suitability and robustness of the present approach for steady-state heat conduction.

  4. Lessons learned in acquiring new regulations for shipping advanced electric vehicle batteries

    NASA Astrophysics Data System (ADS)

    Henriksen, Gary; Hammel, Carol; Altemos, Edward A.

    1994-12-01

    In 1990, the Electric and Hybrid Propulsion Division of the US Department of Energy established its ad hoc EV Battery Readiness Working Group to identify regulatory barriers to the commercialization of advanced EV battery technologies and facilitate the removal of these barriers. A Shipping Sub-Working Group (SSWG) was formed to address the regulatory issues associated with the domestic and international shipment of these new battery technologies. The SSWG invites major industrial developers of advanced battery technologies to join as members and work closely with appropriate domestic and international regulatory authorities to develop suitable regulations and procedures for the safe transport of these new battery technologies. This paper describes the domestic and international regulatory processes for the transport of dangerous goods; reviews the status of shipping regulations for sodium-beta and lithium batteries; and delineates the lessons learned to date in this process. The sodium-beta battery family was the first category of advanced EV batteries to be addressed by the SSWG. It includes both sodium/sulfur and sodium/metal chloride batteries. Their efforts led to the establishment of a UN number (UN 3292) in the UN Recommendations, for cold cells and batteries, and establishment of a US Department of Transportation general exemption (DOT-E-10917) covering cold and hot batteries, as well as cold cells. The lessons learned for sodium-beta batteries, over the period of 1990--94, are now being applied to the development of regulations for shipping a new generation of lithium battery technologies (lithium-polymer and lithium-aluminum/iron sulfide batteries).

  5. Heritability and genetic advance among chili pepper genotypes for heat tolerance and morphophysiological characteristics.

    PubMed

    Usman, Magaji G; Rafii, M Y; Ismail, M R; Malek, M A; Abdul Latif, Mohammad

    2014-01-01

    High temperature tolerance is an important component of adaptation to arid and semiarid cropping environment in chili pepper. Two experiments were carried out to study the genetic variability among chili pepper for heat tolerance and morphophysiological traits and to estimate heritability and genetic advance expected from selection. There was a highly significant variation among the genotypes in response to high temperature (CMT), photosynthesis rate, plant height, disease incidence, fruit length, fruit weight, number of fruits, and yield per plant. At 5% selection intensity, high genetic advance as percent of the mean (>20%) was observed for CMT, photosynthesis rate, fruit length, fruit weight, number of fruits, and yield per plant. Similarly, high heritability (>60%) was also observed indicating the substantial effect of additive gene more than the environmental effect. Yield per plant showed strong to moderately positive correlations (r = 0.23-0.56) at phenotypic level while at genotypic level correlation coefficient ranged from 0.16 to 0.72 for CMT, plant height, fruit length, and number of fruits. Cluster analysis revealed eight groups and Group VIII recorded the highest CMT and yield. Group IV recorded 13 genotypes while Groups II, VII, and VIII recorded one each. The results showed that the availability of genetic variance could be useful for exploitation through selection for further breeding purposes.

  6. ELECTRICAL RESISTANCE HEATING OF SOILS AT C-REACTOR AT THE SAVANNAH RIVER SITE

    SciTech Connect

    Blundy, R; Michael Morgenstern, M; Joseph Amari, J; Annamarie MacMurray, A; Mark Farrar, M; Terry Killeen, T

    2007-09-10

    Chlorinated solvent contamination of soils and groundwater is an endemic problem at the Savannah River Site (SRS), and originated as by-products from the nuclear materials manufacturing process. Five nuclear reactors at the SRS produced special nuclear materials for the nation's defense program throughout the cold war era. An important step in the process was thorough degreasing of the fuel and target assemblies prior to irradiation. Discharges from this degreasing process resulted in significant groundwater contamination that would continue well into the future unless a soil remediation action was performed. The largest reactor contamination plume originated from C-Reactor and an interim action was selected in 2004 to remove the residual trichloroethylene (TCE) source material by electrical resistance heating (ERH) technology. This would be followed by monitoring to determine the rate of decrease in concentration in the contaminant plume. Because of the existence of numerous chlorinated solvent sources around SRS, it was elected to generate in-house expertise in the design and operation of ERH, together with the construction of a portable ERH/SVE system that could be deployed at multiple locations around the site. This paper describes the waste unit characteristics, the ERH system design and operation, together with extensive data accumulated from the first deployment adjacent to the C-Reactor building. The installation heated the vadose zone down to 62 feet bgs over a 60 day period during the summer of 2006 and raised soil temperatures to over 200 F. A total of 730 lbs of trichloroethylene (TCE) were removed over this period, and subsequent sampling indicated a removal efficiency of 99.4%.

  7. THE POTENTIAL OF NANOPARTICLE ENHANCED IONIC LIQUIDS (NEILS) AS ADVANCED HEAT TRANSFER FLUIDS

    SciTech Connect

    Fox, E.; Bridges, N.; Visser, A.

    2011-09-14

    Interest in capturing the energy of the sun is rising as demands for renewable energy sources increase. One area of developing research is the use of concentrating solar power (CSP), where the solar energy is concentrated by using mirrors to direct the sunlight towards a collector filled with a heat transfer fluid (HTF). The HTF transfers the collected energy into pressurized steam, which is used to generate energy. The greater the energy collected by the HTF, the more efficent the electrical energy production is, thus the overall efficiency is controlled by the thermal fluid. Commercial HTFs such as Therminol{reg_sign} (VP-1), which is a blend of biphenyl and diphenyl oxide, have a significant vapor pressure, especially at elevated temperatures. In order for these volatile compounds to be used in CSP systems, the system either has to be engineered to prevent the phase change (i.e., volatilization and condensation) through pressurization of the system, or operate across the phase change. Over thirty years ago, a class of low-melting organic compounds were developed with negligible vapor pressure. These compounds are referred to as ionic liquids (ILs), which are organic-based compounds with discrete charges that cause a significant decrease in their vapor pressure. As a class, ILs are molten salts with a melting point below 100 C and can have a liquidus range approaching 400 C, and in several cases freezing points being below 0 C. Due to the lack of an appreciable vapor pressure, volatilization of an IL is not possible at atmospheric pressure, which would lead to a simplification of the design if used as a thermal fluid and for energy storage materials. Though the lack of a vapor pressure does not make the use of ILs a better HTF, the lack of a vapor pressure is a compliment to their higher heat capacity, higher volummetric density, and thus higher volumetric heat capacity. These favorable physical properties give ILs a pontential advantage over the current

  8. Citrate-capped gold nanoparticle electrophoretic heat production in response to a time-varying radiofrequency electric-field

    PubMed Central

    Corr, Stuart J.; Raoof, Mustafa; Mackeyev, Yuri; Phounsavath, Sophia; Cheney, Matthew A.; Cisneros, Brandon T.; Shur, Michael; Gozin, Michael; McNally, Patrick J.; Wilson, Lon J.; Curley, Steven A.

    2013-01-01

    The evaluation of heat production from gold nanoparticles (AuNPs) irradiated with radiofrequency (RF) energy has been problematic due to Joule heating of their background ionic buffer suspensions. Insights into the physical heating mechanism of nanomaterials under RF excitations must be obtained if they are to have applications in fields such as nanoparticle-targeted hyperthermia for cancer therapy. By developing a purification protocol which allows for highly-stable and concentrated solutions of citrate-capped AuNPs to be suspended in high-resistivity water, we show herein, for the first time, that heat production is only evident for AuNPs of diameters ≤ 10 nm, indicating a unique size-dependent heating behavior not previously observed. Heat production has also shown to be linearly dependent on both AuNP concentration and total surface area, and severely attenuated upon AuNP aggregation. These relationships have been further validated using permittivity analysis across a frequency range of 10 MHz to 3 GHz, as well as static conductivity measurements. Theoretical evaluations suggest that the heating mechanism can be modeled by the electrophoretic oscillation of charged AuNPs across finite length scales in response to a time-varying electric field. It is anticipated these results will assist future development of nanoparticle-assisted heat production by RF fields for applications such as targeted cancer hyperthermia. PMID:23795228

  9. Design of a pool boiler heat transport system for a 25 kWe advanced Stirling conversion system

    NASA Technical Reports Server (NTRS)

    Anderson, W. G.; Rosenfeld, J. H.; Noble, J.; Kesseli, J.

    1991-01-01

    The overall operating temperature and efficiency of solar-powered Stirling engines can be improved by adding a heat transport system to more uniformly supply heat to the heater head tubes. One heat transport system with favorable characteristics is an alkali metal pool boiler. An alkali metal pool boiler heat transport system was designed for a 25-kW advanced Stirling conversion system (ASCS). Solar energy concentrated on the absorber dome boils a eutectic mixture of sodium and potassium. The alkali metal vapors condense on the heater head tubes, supplying the Stirling engine with a uniform heat flux at a constant temperature. Boiling stability is achieved with the use of an enhanced boiling surface and noncondensible gas.

  10. Observations of compound sawteeth in ion cyclotron resonant heating plasma using ECE imaging on experimental advanced superconducting tokamak

    NASA Astrophysics Data System (ADS)

    Hussain, Azam; Zhao, Zhenling; Xie, Jinlin; Zhu, Ping; Liu, Wandong; Ti, Ang

    2016-04-01

    The spatial and temporal evolutions of compound sawteeth were directly observed using 2D electron cyclotron emission imaging on experimental advanced superconducting tokamak. The compound sawtooth consists of partial and full collapses. After partial collapse, the hot core survives as only a small amount of heat disperses outwards, whereas in the following full collapse a large amount of heat is released and the hot core dissipates. The presence of two q = 1 surfaces was not observed. Instead, the compound sawtooth occurs mainly at the beginning of an ion cyclotron resonant frequency heating pulse and during the L-H transition phase, which may be related to heat transport suppression caused by a decrease in electron heat diffusivity.

  11. Heat-Pipe Development for Advanced Energy Transport Concepts Final Report Covering the Period January 1999 through September 2001

    SciTech Connect

    R.S.Reid; J.F.Sena; A.L.Martinez

    2002-10-01

    This report summarizes work in the Heat-pipe Technology Development for the Advanced Energy Transport Concepts program for the period January 1999 through September 2001. A gas-loaded molybdenum-sodium heat pipe was built to demonstrate the active pressure-control principle applied to a refractory metal heat pipe. Other work during the period included the development of processing procedures for and fabrication and testing of three types of sodium heat pipes using Haynes 230, MA 754, and MA 956 wall materials to assess the compatibility of these materials with sodium. Also during this period, tests were executed to measure the response of a sodium heat pipe to the penetration of water.

  12. Mitsubishi iMiEV: An Electric Mini-Car in NREL's Advanced Technology Vehicle Fleet (Fact Sheet)

    SciTech Connect

    Not Available

    2011-10-01

    This fact sheet highlights the Mitsubishi iMiEV, an electric mini-car in the advanced technology vehicle fleet at the National Renewable Energy Laboratory (NREL). In support of the U.S. Department of Energy's fast-charging research efforts, NREL engineers are conducting charge and discharge performance testing on the vehicle. NREL's advanced technology vehicle fleet features promising technologies to increase efficiency and reduce emissions without sacrificing safety or comfort. The fleet serves as a technology showcase, helping visitors learn about innovative vehicles that are available today or are in development. Vehicles in the fleet are representative of current, advanced, prototype, and emerging technologies.

  13. Environmental tobacco smoke (ETS) evaluation of a third-generation electrically heated cigarette smoking system (EHCSS).

    PubMed

    Frost-Pineda, Kimberly; Zedler, Barbara K; Liang, Qiwei; Roethig, Hans J

    2008-11-01

    This sub-study of a randomized, controlled, forced-switching, open-label, parallel-group, clinical study compared environmental tobacco smoke (ETS) produced when 60 male and female adult smokers switched to a third-generation electrically heated cigarette smoking system (EHCSS), continued to smoke a conventional cigarette (CC), or stopped smoking (No-smoking). Concentrations of air constituents including respirable suspended particulate (RSP), carbon monoxide (CO), ammonia and total volatile organic compounds (TVOCs) and ETS markers including solanesol-related particulate matter (Sol-PM), ultraviolet absorbing particulate matter (UVPM), fluorescent particulate matter (FPM), nicotine and 3-ethenyl pyridine (3-EP) were measured in a ventilated, furnished conference room over a 2-h period on separate occasions for each smoking condition. When the EHCSS was used, concentrations of CO and most ETS markers were in the same range as during no-smoking. Concentrations of ammonia were reduced by 41% and concentrations of other selected constituents of ETS were reduced by 87-99% in the air of a room in which EHCSS cigarettes were smoked as compared to concentrations in the same room when conventional cigarettes were smoked. Switching from conventional cigarette smoking to the EHCSS resulted in substantial reductions in concentrations of several markers of environmental tobacco smoke.

  14. Investigation of an Electrically Heated Airplane Windshield for Ice Prevention, Special Report

    NASA Technical Reports Server (NTRS)

    Rodert, Lewis A.

    1939-01-01

    A study was made at the National Advisory Committee for Aeronautics Laboratory of the operation of an electrically heated glass panel, which simulated a segment of an airplane windshield, to determine if ice formations, which usually result in the loss of visibility, could be prevented. Tests were made in the 7- by 3-foot ice tunnel, and in flight, under artificially created ice-forming conditions. Ice was prevented from forming on the windshield model in the tunnel by 1.25 watts of power per square inch with the air temperature at 23 F and a velocity of 80 miles per hour. Using an improved model in flight, ice was prevented by 1.43 watts of power per square inch of protected area and 2 watts per inch concentrated in the rim, with the air temperature at 26 F and a velocity of 120 miles per hour. The removal of a preformed ice cap was effected to a limited extent in the tunnel by the use of 1.89 watts of power per square inch when the temperature and velocity were 25 F and 80 miles per hour, respectively. The results indicate that service tests with an improved design are justified.

  15. Solar-assisted electric clothes dryer using a home attic as a heat source

    SciTech Connect

    Stana, J. M.

    1983-01-01

    This study was undertaken to determine the suitability of using a southeastern home attic as a means of reducing the energy consumption of an electric clothes dryer. An inexpensive duct (duplicable for $25) was constructed to collect hot attic air from the peak of a south facing roof and introduce it into the dryer inlet. Instrumentation was added to measure inlet temperatures and operating time/energy consumption of the dryer. Standardized test loads, in addition to normal laundry, were observed over the period of one year. The heat-on time of the dryer tested was shown to be reduced .16 to .35 minutes per /sup 0/C rise in inlet temperature. Inlet temperatures produced by the attic duct peaked at 56/sup 0/C(133/sup 9/F) in May/June and 40/sup 0/C(104/sup 0/F) in February. Based on peak temperatures available between 2 and 4 pm each month, a potential 20% yearly average savings could be realized. Economic viability of the system, dependant primarily on dryer usage, can be computed using a formula derived from the test results and included in the report.

  16. Heat and electricity from the Sun using parabolic dish collector systems

    NASA Technical Reports Server (NTRS)

    Truscello, V. C.; Williams, A. N.

    1980-01-01

    Point focus distributed receiver solar thermal technology for the production of electric power and of industrial process heat is addressed. The thermal power systems project which emphasizes the development of cost effective systems which will accelerate the commercialization and industrialization of plants up to 10 MWe, using parabolic dish collectors is described. The projected size of the isolated load market in the 1990-2000 time period is 300 to 1000 MW/year. Although this market is small in comparison to the grid connected utility market, it is indicated that by assuming only a 20 percent market penetration, up to 10,000 power modules per year would be required to meet this need. At a production rate of 25,000 units/year and assuming no energy storage, levelized bus bar energy costs of 75 mills/kWeh are projected. These numbers are based on what is believed to be a conservative estimate regarding engine-generator conversion efficiency (40 percent) for the 1990 time period. With a more optimistic estimate of efficiency (i.e., 45 percent), the bus bar cost decreases to about 67 mills/kWeh. At very large production rates (400,000 modules/years), the costs decrease to 58 mills/kWeh. Finally, the present status of the technology development effort is discussed.

  17. Demonstration of Combined Zero-Valent Iron and Electrical Resistance Heating for In Situ Trichloroethene Remediation

    SciTech Connect

    Truex, Michael J.; Macbeth, Tamzen; Vermeul, Vincent R.; Fritz, Brad G.; Mendoza, Donaldo P.; Mackley, Rob D.; Wietsma, Thomas W.; Sandberg, Greg; Powell, Thomas; Powers, Jeff; Pitre, Emile; Michalsen, Mandy M.; Ballock-Dixon, Sage; Zhong, Lirong; Oostrom, Martinus

    2011-06-27

    The effectiveness of in situ treatment using zero-valent iron to remediate sites with non-aqueous phase or significant sediment-associated contaminant mass can be limited by relatively low rates of mass transfer to bring contaminants in contact with the reactive media. For a field test in a trichloroethene source area, combining moderate-temperature (maximum 50oC) subsurface electrical resistance heating with in situ ZVI treatment was shown to accelerate dechlorination and dissolution rates by a factor of 4 to 6 based on organic daughter products and a factor 8-16 using a chloride concentrations. A mass-discharge-based analysis was used to evaluate reaction, dissolution, and volatilization at ambient groundwater temperature (~10oC) and as temperature was increased up to about 50oC. Increased reaction and contaminant dissolution were observed with increased temperature, but volatilization was minimal during the test because in situ reactions maintained low aqueous-phase TCE concentrations.

  18. Recent advances in eye-safe Er:YAG solid-state heat-capacity technology

    NASA Astrophysics Data System (ADS)

    Eichhorn, Marc; Bigotta, Stefano; Ibach, Thierry

    2012-11-01

    In order to address the question of the possibility of a high energy laser with an emission in the "eye-safe" wavelength range, various architectures may be considered. To provide a truly scalable and efficient laser source, however, only bulk solid-state lasers using resonantly diode-pumped erbium show the necessary properties, when coupled with the solid-state heat-capacity (SSHCL) principle of operation. Although seen as nearly being impossible to realize, such a quasi-three-level laser medium can be used in heat-capacity operation. In this operation mode, the laser medium is not cooled during lasing in order to avoid the thermal lensing occurring in bulk lasers, which, in actively cooled operation, would result in a low beam quality, destabilize the laser cavity or would even cause crystal fracture. In heat-capacity mode, the laser medium will substantially heat up during operation, which will cause an increase in re-absorption for a quasi-three-level laser medium, resulting in a general drop in output power over time. However, theoretical and experimental investigations have proven that this effectis of no concern for an Er3+:YAG SSHCL. This paper presents an overview on the theoretical background of the Er3+:YAG SSHCL, experimental results including recent advances in output power and efficiency, an investigation on the laser scaling properties and recent results on intra-cavity adaptive optics for beam-quality enhancement. The effect of fluorescence re-absorption on the laser properties, especially on threshold and laser efficiency will also be discussed. Up to 4.65 kW and 440 J in less than 800 ms are achieved using optimized doping levels for upconversion reduction in this resonantly-diode-pumped Er3+:YAG SSHCL, representing the current world record in eye-safe diode-pumped solid-state laser technology. Optical-to-optical efficiencies of over 41% and slope efficiencies of over 51% are obtained with respect to the incident pump power.

  19. Measurement and simulation of Joule heating during treatment of B-16 melanoma tumors in mice with nanosecond pulsed electric fields.

    PubMed

    Pliquett, Uwe; Nuccitelli, Richard

    2014-12-01

    Experimental evidence shows that nanosecond pulsed electric fields (nsPEF) trigger apoptosis in skin tumors. We have postulated that the energy delivered by nsPEF is insufficient to impart significant heating to the treated tissue. Here we use both direct measurements and theoretical modeling of the Joule heating in order to validate this assumption. For the temperature measurement, thermo-sensitive liquid crystals (TLC) were used to determine the surface temperature while a micro-thermocouple (made from 30 μm wires) was used for measuring the temperature inside the tissue. The calculation of the temperature distribution used an asymptotic approach with the repeated calculation of the electric field, Joule heating and heat transfer, and the subsequent readjustment of the electrical tissue conductivity. This yields a temperature distribution both in space and time. It can be shown that for the measured increase in temperature an unexpectedly high electrical conductivity of the tissue would be required, which was indeed found by using voltage and current monitoring during the experiment. Using impedance measurements within t(after)=50 μs after the pulse revealed a fast decline of the high conductivity state when the electric field ceases. The experimentally measured high conductance of a skin fold (mouse) between plate electrodes was about 5 times higher than those of the maximally expected conductance due to fully electroporated membrane structures (G(max)/G(electroporated))≈5. Fully electroporated membrane structure assumes that 100% of the membranes are conductive which is estimated from an impedance measurement at 10 MHz where membranes are capacitively shorted. Since the temperature rise in B-16 mouse melanoma tumors due to equally spaced (Δt=2 s) 300 ns-pulses with E=40 kV/cm usually does not exceed ΔΤ=3 K at all parts of the skin fold between the electrodes, a hyperthermic effect on the tissue can be excluded.

  20. Determination of thermophysical characteristics of solid materials by electrical modelling of the solutions to the inverse problems in nonsteady heat conduction

    NASA Technical Reports Server (NTRS)

    Kozdoba, L. A.; Krivoshei, F. A.

    1985-01-01

    The solution of the inverse problem of nonsteady heat conduction is discussed, based on finding the coefficient of the heat conduction and the coefficient of specific volumetric heat capacity. These findings are included in the equation used for the electrical model of this phenomenon.

  1. Thermoelectric Conversion of Waste Heat to Electricity in an IC Engine Powered Vehicle

    SciTech Connect

    2012-01-31

    The thermoelectric generator shorting system provides the capability to monitor and short-out individual thermoelectric couples in the event of failure. This makes the series configured thermoelectric generator robust to individual thermoelectric couple failure. Open circuit detection of the thermoelectric couples and the associated short control is a key technique to ensure normal functionality of the TE generator under failure of individual TE couples. This report describes a five-year effort whose goal was the understanding the issues related to the development of a thermoelectric energy recovery device for a Class-8 truck. Likely materials and important issues related to the utility of this generator were identified. Several prototype generators were constructed and demonstrated. The generators developed demonstrated several new concepts including advanced insulation, couple bypass technology and the first implementation of skutterudite thermoelectric material in a generator design. Additional work will be required to bring this system to fruition. However, such generators offer the possibility of converting energy that is otherwise wasted to useful electric power. Uur studies indicate that this can be accomplished in a cost-effective manner for this application.

  2. Effects of high-latitude ionospheric electric field variability on the estimation of global thermospheric Joule heating

    NASA Astrophysics Data System (ADS)

    Matsuo, Tomoko

    One of the outstanding problems in modeling of the magnetosphere-ionosphere-thermosphere system is the quantitative bias systematically seen in simulated thermosphere and ionosphere responses to magnetospheric forcing. This systematic bias is considered to be attributed largely to insufficient Joule heating. In this study, effects of high-latitude ionospheric electric field variability on the estimation of Joule heating are investigated by incorporating the characteristics of electric field variability derived from observations into the forcing of a thermosphere-ionosphere-electrodynamic general circulation model (TIEGCM). First, the magnitude of the variability is quantified as the sample standard deviation of plasma drift measurements from the Dynamics Explorer (DE-2) satellite. The spatial distribution of the standard deviation over the area poleward of 45° magnetic latitude and its climatological behavior with respect to the magnitude and orientation of the interplanetary magnetic field (IMF) and the dipole tilt angle (season) are examined. In general, the magnitude of the standard deviation exceeds the strength of the mean electric field in most of the polar area, especially under northward IMF conditions. The analysis reveals that electric field variability varies with magnetic-latitude, magnetic-local-time, IMF, and season in a manner distinct from that of the climatological electric field. Second, we characterize dominant modes of high-latitude electric field variability as a set of two-dimensional empirical orthogonal functions (EOFs), based on a sequential non-linear regression analysis of the electric field derived from DE-2 data. Together with the mean fields, 11 EOFs are capable of representing 68% of the squared electric field, leaving only a fairly random component as a residual. Third, the temporal coherence of electric field variability whose spatial coherence can be represented in the form of EOFs is estimated for the storm period of January 9

  3. THE NONLINEAR OHM'S LAW: PLASMA HEATING BY STRONG ELECTRIC FIELDS AND ITS EFFECTS ON THE IONIZATION BALANCE IN PROTOPLANETARY DISKS

    SciTech Connect

    Okuzumi, Satoshi; Inutsuka, Shu-ichiro

    2015-02-10

    The ionization state of the gas plays a key role in the magnetohydrodynamics (MHD) of protoplanetary disks. However, the ionization state can depend on the gas dynamics, because electric fields induced by MHD turbulence can heat up plasmas and thereby affect the ionization balance. To study this nonlinear feedback, we construct an ionization model that includes plasma heating by electric fields and impact ionization by heated electrons, as well as charging of dust grains. We show that when plasma sticking onto grains is the dominant recombination process, the electron abundance in the gas decreases with increasing electric field strength. This is a natural consequence of electron-grain collisions whose frequency increases with the electron's random velocity. The decreasing electron abundance may lead to a self-regulation of MHD turbulence. In some cases, not only the electron abundance but also the electric current decreases with increasing field strength in a certain field range. The resulting N-shaped current-field relation violates the fundamental assumption of the non-relativistic MHD that the electric field is uniquely determined by the current density. At even higher field strengths, impact ionization causes an abrupt increase of the electric current as expected by previous studies. We find that this discharge current is multi-valued (i.e., the current-field relation is S-shaped) under some circumstances, and that the intermediate branch is unstable. The N/S-shaped current-field relations may yield hysteresis in the evolution of MHD turbulence in some parts of protoplanetary disks.

  4. The Nonlinear Ohm's Law: Plasma Heating by Strong Electric Fields and its Effects on the Ionization Balance in Protoplanetary Disks

    NASA Astrophysics Data System (ADS)

    Okuzumi, Satoshi; Inutsuka, Shu-ichiro

    2015-02-01

    The ionization state of the gas plays a key role in the magnetohydrodynamics (MHD) of protoplanetary disks. However, the ionization state can depend on the gas dynamics, because electric fields induced by MHD turbulence can heat up plasmas and thereby affect the ionization balance. To study this nonlinear feedback, we construct an ionization model that includes plasma heating by electric fields and impact ionization by heated electrons, as well as charging of dust grains. We show that when plasma sticking onto grains is the dominant recombination process, the electron abundance in the gas decreases with increasing electric field strength. This is a natural consequence of electron-grain collisions whose frequency increases with the electron's random velocity. The decreasing electron abundance may lead to a self-regulation of MHD turbulence. In some cases, not only the electron abundance but also the electric current decreases with increasing field strength in a certain field range. The resulting N-shaped current-field relation violates the fundamental assumption of the non-relativistic MHD that the electric field is uniquely determined by the current density. At even higher field strengths, impact ionization causes an abrupt increase of the electric current as expected by previous studies. We find that this discharge current is multi-valued (i.e., the current-field relation is S-shaped) under some circumstances, and that the intermediate branch is unstable. The N/S-shaped current-field relations may yield hysteresis in the evolution of MHD turbulence in some parts of protoplanetary disks.

  5. In-line application of electric field in capillary separation systems: Joule heating, pH and conductivity.

    PubMed

    Eriksson, Björn O; Skuland, Inger Lill; Marlin, Nicola D; Andersson, Magnus B O; Blomberg, Lars G

    2008-03-15

    This study concerns the technique electric field-assisted capillary liquid chromatography. In this technique, an electric field is applied over the separation capillary in order to provide an additional selectivity. In this technique, the electric field is applied in-line in the separation capillary and here the electric current is the factor limiting the magnitude of applied electric field. The influence of Joule heating and other factors on the current in such systems has been investigated. The temperature in the capillary was first measured within a standard CE set-up, as function of effect per unit of length. Then the same cooling system was applied to an in-line set-up, to replicate the conditions between the two systems, and thus the temperature. Thus Joule heating effects could then be calculated within the in-line system. It was found that for systems applying an electric field in line, the direct influence from Joule heating was only relatively small. The pH in the capillary was measured in the in-line set-up using cresol red/TRIS solutions as pH probe. Significant changes in pH were observed and the results suggested that electrolysis of water is the dominant electrode reaction in the in-line system. In summary, the observed conductivity change in in-line systems was found to be mainly due to the pH change by hydrolysis of water, but primarily not due the temperature change in the capillary column.

  6. Experimental investigation on heat pipe cooling for Hybrid Electric Vehicle and Electric Vehicle lithium-ion battery

    NASA Astrophysics Data System (ADS)

    Tran, Thanh-Ha; Harmand, Souad; Sahut, Bernard

    2014-11-01

    In this work, we explored the use of heat pipe as cooling device for a specific HEV lithium-ion battery module. The evaporator blocks of heat pipe modules were fixed to a copper plate which played the role of the battery cooling wall. A flat heater was glued to the other surface of the copper plate and reproduced heat generated by the battery. The temperature at the cooper plate/heater interface corresponds to that of the battery module wall. An AMESim model of the battery was developed to estimate the cells' temperature within the battery. In inclined positions, a very slender evolution of the cooper plate/heater interface temperature was noticed, which means heat pipe works efficiently under different grade road conditions. Even though natural convection and chimney effect are not enough, coupling heat pipes with a confined ventilation structure is an efficient way to keep cells' temperature within its optimal range with an even temperature distribution. Furthermore, only low rate ventilation is necessary, which helps avoid parasitic power consumption and noise level in the vehicle.

  7. Convective Heat Transfer Coefficients of Automatic Transmission Fluid Jets with Implications for Electric Machine Thermal Management: Preprint

    SciTech Connect

    Bennion, Kevin; Moreno, Gilberto

    2015-09-29

    Thermal management for electric machines (motors/ generators) is important as the automotive industry continues to transition to more electrically dominant vehicle propulsion systems. Cooling of the electric machine(s) in some electric vehicle traction drive applications is accomplished by impinging automatic transmission fluid (ATF) jets onto the machine's copper windings. In this study, we provide the results of experiments characterizing the thermal performance of ATF jets on surfaces representative of windings, using Ford's Mercon LV ATF. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients. Fluid temperatures were varied from 50 degrees C to 90 degrees C to encompass potential operating temperatures within an automotive transaxle environment. The jet nozzle velocities were varied from 0.5 to 10 m/s. The experimental ATF heat transfer coefficient results provided in this report are a useful resource for understanding factors that influence the performance of ATF-based cooling systems for electric machines.

  8. Evaluation of non-thermal effects of electricity on anthocyanin degradation during ohmic heating of jaboticaba (Myrciaria cauliflora) juice.

    PubMed

    Mercali, Giovana Domeneghini; Gurak, Poliana Deyse; Schmitz, Frederico; Marczak, Ligia Damasceno Ferreira

    2015-03-15

    This study investigated the non-thermal effects of electricity on anthocyanin degradation during ohmic heating of jaboticaba juice. For this, temperature profiles during conventional and ohmic heating processes were matched, and the degradation kinetics of anthocyanins were compared at temperatures ranging from 70 to 90°C. The monomeric anthocyanin content was quantified by UV-Visible spectroscopy using the pH-differential method. Anthocyanin degradation was fitted to a first-order model. The rate constants ranged from 1.7 to 7.5 × 10(-3)min(-1) and from 1.8 to 7.6 × 10(-3)min(-1) for ohmic and conventional heating, respectively. The analysis of variance (α=0.05) showed no significant differences between rate constants of the ohmic and conventional heating at the same temperatures. All kinetic and thermodynamic parameters evaluated showed similar values for both technologies. These results indicate that the presence of the oscillating electric field did not affect the degradation rates of anthocyanins during ohmic heating.

  9. High thermally conductive and electrically insulating 2D boron nitride nanosheet for efficient heat dissipation of high-power transistors

    NASA Astrophysics Data System (ADS)

    Lin, Ziyuan; Liu, Chunru; Chai, Yang

    2016-12-01

    High-power transistors suffer greatly from inefficient heat dissipation of the hotspots, which elevate the local temperature and significantly degrade the performance and reliability of the high-power devices. Although various thermal management methods at package-level have been demonstrated, the heat dissipation from non-uniform hotspots at micro/nanoscale still persist in the high power transistors. Here, we develop a method for local thermal management using thermally conductive and electrical insulating few-layer hexagonal boron nitride (h-BN) as heat spreaders and thick counterpart as heat sinks. The electrically insulating characteristic of h-BN nanosheet allows it to be intimately contacted with the hotspot region that is located at the gate electrode edge near the drain side of a high-electron-mobility transistor (HEMT). The high thermal conductivity of h-BN nanosheet, which is quantitatively measured by Raman thermography, reduces the temperature of the hotspot by introducing an additional heat transporting pathway. Our DC and radio-frequency characterizations of the HEMT show the improvement of saturation current, cut-off frequency and maximum oscillation frequency. The finite element simulations show a temperature decrease of ∼32 °C at the hotspot with the use of h-BN nanosheet. This method can be further extended for the micro/nanoscale thermal management of other high-power devices.

  10. The dependence of radiofrequency induced pacemaker lead tip heating on the electrical conductivity of the medium at the lead tip.

    PubMed

    Langman, Deborah A; Goldberg, Ira B; Judy, Jack; Paul Finn, J; Ennis, Daniel B

    2012-08-01

    Radiofrequency induced pacemaker lead tip heating is one of the main reasons magnetic resonance imaging (MRI) is contraindicated for patients with pacemakers. The objective of this work was to evaluate the dependence of pacemaker lead tip heating during MRI scanning on the electrical conductivity of the medium surrounding the pacemaker lead tip. The effect of conductivity was measured using hydroxyethyl cellulose, polyacrylic acid, and saline with conductivities ranging from 0 to 3 S/m which spans the range of human tissue conductivity. The maximum lead tip heating observed in polyacrylic acid was 50.4 °C at 0.28 S/m, in hydroxyethyl cellulose the maximum was 36.8 °C at 0.52 S/m, and in saline the maximum was 12.5 °C at 0.51 S/m. The maximum power transfer theorem was used to calculate the relative power deposited in the solution based on the characteristic impedance of the pacemaker lead and test solution impedance. The results demonstrate a strong correlation between the relative power deposited and pacemaker lead tip heating for hydroxyethyl cellulose and saline solutions. Maximum power deposition occurred when the impedance of the solution matched the pacemaker lead impedance. Pacemaker lead tip heating is dependent upon the electrical conductivity of the solution at the lead tip and should be considered when planning in vitro gel or saline experiments.

  11. Advanced two-photon photolithography for patterning of transparent, electrically conductive ionic liquid-polymer nanostructures

    NASA Astrophysics Data System (ADS)

    Bakhtina, Natalia A.; MacKinnon, Neil; Korvink, Jan G.

    2016-04-01

    A key challenge in micro- and nanotechnology is the direct patterning of functional structures. For example, it is highly desirable to possess the ability to create three-dimensional (3D), conductive, and optically transparent structures. Efforts in this direction have, to date, yielded less than optimal results since the polymer composites had low optical transparency over the visible range, were only slightly conductive, or incompatible with high resolution structuring. We have previously presented the novel cross-linkable, conductive, highly transparent composite material based on a photoresist (IP-L 780, OrmoComp, or SU-8) and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. Material patterning by conventional and two-photon photolithography has been demonstrated as proof-of-concept. Aiming to increase the resolution and to extend the spectrum of exciting applications we continued our research into identifying new ionic liquid - polymer composites. In this paper, we report the precise 3D single-step structuring of optically transparent and electrically conductive ionic liquid - polymer nanostructures with the highest spatial resolution (down to 150 nm) achieved to date. This was achieved via the development of novel cross-linkable composite based on the photoresist IP-G 780 and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. The successful combination of the developed material with the advanced direct laser writing technique enabled the time- and cost-saving direct manufacturing of transparent, electrically conductive components. We believe that the excellent characteristics of the structured material will open a wider range of exciting applications.

  12. Advances in three-dimensional field analysis and evaluation of performance parameters of electrical machines

    NASA Astrophysics Data System (ADS)

    Sivasubramaniam, Kiruba

    This thesis makes advances in three dimensional finite element analysis of electrical machines and the quantification of their parameters and performance. The principal objectives of the thesis are: (1)the development of a stable and accurate method of nonlinear three-dimensional field computation and application to electrical machinery and devices; and (2)improvement in the accuracy of determination of performance parameters, particularly forces and torque computed from finite elements. Contributions are made in two general areas: a more efficient formulation for three dimensional finite element analysis which saves time and improves accuracy, and new post-processing techniques to calculate flux density values from a given finite element solution. A novel three-dimensional magnetostatic solution based on a modified scalar potential method is implemented. This method has significant advantages over the traditional total scalar, reduced scalar or vector potential methods. The new method is applied to a 3D geometry of an iron core inductor and a permanent magnet motor. The results obtained are compared with those obtained from traditional methods, in terms of accuracy and speed of computation. A technique which has been observed to improve force computation in two dimensional analysis using a local solution of Laplace's equation in the airgap of machines is investigated and a similar method is implemented in the three dimensional analysis of electromagnetic devices. A new integral formulation to improve force calculation from a smoother flux-density profile is also explored and implemented. Comparisons are made and conclusions drawn as to how much improvement is obtained and at what cost. This thesis also demonstrates the use of finite element analysis to analyze torque ripples due to rotor eccentricity in permanent magnet BLDC motors. A new method for analyzing torque harmonics based on data obtained from a time stepping finite element analysis of the machine is

  13. Physics-Based Modeling of Electric Operation, Heat Transfer, and Scrap Melting in an AC Electric Arc Furnace

    NASA Astrophysics Data System (ADS)

    Opitz, Florian; Treffinger, Peter

    2016-04-01

    Electric arc furnaces (EAF) are complex industrial plants whose actual behavior depends upon numerous factors. Due to its energy intensive operation, the EAF process has always been subject to optimization efforts. For these reasons, several models have been proposed in literature to analyze and predict different modes of operation. Most of these models focused on the processes inside the vessel itself. The present paper introduces a dynamic, physics-based model of a complete EAF plant which consists of the four subsystems vessel, electric system, electrode regulation, and off-gas system. Furthermore the solid phase is not treated to be homogenous but a simple spatial discretization is employed. Hence it is possible to simulate the energy input by electric arcs and fossil fuel burners depending on the state of the melting progress. The model is implemented in object-oriented, equation-based language Modelica. The simulation results are compared to literature data.

  14. Influence of the thermo-electric coupling on the heat transfer in cylindrical annulus with a dielectric fluid under microgravity

    NASA Astrophysics Data System (ADS)

    Travnikov, Vadim; Crumeyrolle, Olivier; Mutabazi, Innocent

    2016-12-01

    The present note gives the result of direct numerical simulations of the convective flow induced by the dielectric force in a cylindrical annulus under microgravity conditions. A dielectric fluid confined between two coaxial cylinders is subject to a high-frequency tension and a radial temperature gradient. The resulting buoyancy force creates a supercritical convective flow when the critical value of the electric Rayleigh number is exceeded. This flow is made of stationary helicoidal vortices. The effect of the thermo-electric coupling is sensitive for large values of the radius ratio: it stabilizes the conductive state and reduces the slope of the increase of the heat transfer and of the kinetic energy.

  15. High Efficiency Water Heating Technology Development Final Report. Part I, Lab/Field Performance Evaluation and Accelerated Life Testing of a Hybrid Electric Heat Pump Water Heater (HPWH)

    SciTech Connect

    Baxter, Van D.; Murphy, Richard W.; Rice, C. Keith; Linkous, Randall Lee

    2016-04-01

    DOE has supported efforts for many years with the objective of getting a water heater that uses heat pump technology (aka a heat pump water heater or HPWH) successfully on the residential equipment market. The most recent previous effort (1999-2002) produced a product that performed very well in ORNL-led accelerated durability and field tests. The commercial partner for this effort, Enviromaster International (EMI), introduced the product to the market under the trade name Watter$aver in 2002 but ceased production in 2005 due to low sales. A combination of high sales price and lack of any significant infrastructure for service after the sale were the principal reasons for the failure of this effort. What was needed for market success was a commercial partner with the manufacturing and market distribution capability necessary to allow economies of scale to lead to a viable unit price together with a strong customer service infrastructure. General Electric certainly meets these requirements, and knowing of ORNL s expertise in this area, approached ORNL with the proposal to partner in a CRADA to produce a high efficiency electric water heater. A CRADA with GE was initiated early in Fiscal Year, 2008. GE initially named its product the Hybrid Electric Water Heater (HEWH).

  16. Electricity

    SciTech Connect

    Sims, B.

    1983-01-01

    Historical aspects of electricity are reviewed with individual articles on hydroelectric dams, coal-burning power plants, nuclear power plants, electricity distribution, and the energy future. A glossary is included. (PSB)

  17. Development of heat transfer enhancement techniques for external cooling of an advanced reactor vessel

    NASA Astrophysics Data System (ADS)

    Yang, Jun

    Nucleate boiling is a well-recognized means for passively removing high heat loads (up to ˜106 W/m2) generated by a molten reactor core under severe accident conditions while maintaining relatively low reactor vessel temperature (<800 °C). With the upgrade and development of advanced power reactors, however, enhancing the nucleate boiling rate and its upper limit, Critical Heat Flux (CHF), becomes the key to the success of external passive cooling of reactor vessel undergoing core disrupture accidents. In the present study, two boiling heat transfer enhancement methods have been proposed, experimentally investigated and theoretically modelled. The first method involves the use of a suitable surface coating to enhance downward-facing boiling rate and CHF limit so as to substantially increase the possibility of reactor vessel surviving high thermal load attack. The second method involves the use of an enhanced vessel/insulation design to facilitate the process of steam venting through the annular channel formed between the reactor vessel and the insulation structure, which in turn would further enhance both the boiling rate and CHF limit. Among the various available surface coating techniques, metallic micro-porous layer surface coating has been identified as an appropriate coating material for use in External Reactor Vessel Cooling (ERVC) based on the overall consideration of enhanced performance, durability, the ease of manufacturing and application. Since no previous research work had explored the feasibility of applying such a metallic micro-porous layer surface coating on a large, downward facing and curved surface such as the bottom head of a reactor vessel, a series of characterization tests and experiments were performed in the present study to determine a suitable coating material composition and application method. Using the optimized metallic micro-porous surface coatings, quenching and steady-state boiling experiments were conducted in the Sub

  18. Bias induced modulation of electrical and thermal conductivity and heat capacity of BN and BN/graphene bilayers

    NASA Astrophysics Data System (ADS)

    Chegel, Raad

    2017-04-01

    By using the tight binding approximation and Green function method, the electronic structure, density of state, electrical conductivity, heat capacity of BN and BN/graphene bilayers are investigated. The AA-, AB1- and AB2- BN/graphene bilayers have small gap unlike to BN bilayers which are wide band gap semiconductors. Unlike to BN bilayer, the energy gap of graphene/BN bilayers increases with external field. The magnitude of the change in the band gap of BN bilayers is much higher than the graphene/BN bilayers. Near absolute zero, the σ(T) is zero for BN bilayers and it increases with temperature until reaches maximum value then decreases. The BN/graphene bilayers have larger electrical conductivity larger than BN bilayers. For both bilayers, the specific heat capacity has a Schottky anomaly.

  19. Comparison of forced-air warming and electric heating pad for maintenance of body temperature during total knee replacement.

    PubMed

    Ng, V; Lai, A; Ho, V

    2006-11-01

    We conducted a randomised controlled trial to compare the efficacy of forced-air warming (Bair Hugger(trade mark), Augustine Medical model 500/OR, Prairie, MN) with that of an electric heating pad (Operatherm 202, KanMed, Sweden) for maintenance of intra-operative body temperature in 60 patients undergoing total knee replacement under combined spinal-epidural anaesthesia. Intra-operative tympanic and rectal temperatures and verbal analogue score for thermal comfort were recorded. There were no differences in any measurements between the two groups, with mean (SD) final rectal temperatures of 36.8 (0.4) degrees C with forced-air warming and 36.9 (0.4) degrees C with the electric pad. The heating pad is as effective as forced-air warming for maintenance of intra-operative body temperature.

  20. A Soft-Switching Inverter for High-Temperature Advanced Hybrid Electric Vehicle Traction Motor Drives

    SciTech Connect

    Lai, Jason; Yu, Wensong; Sun, Pengwei; Leslie, Scott; Prusia, Duane; Arnet, Beat; Smith, Chris; Cogan, Art

    2012-03-31

    The state-of-the-art hybrid electric vehicles (HEVs) require the inverter cooling system to have a separate loop to avoid power semiconductor junction over temperatures because the engine coolant temperature of 105°C does not allow for much temperature rise in silicon devices. The proposed work is to develop an advanced soft-switching inverter that will eliminate the device switching loss and cut down the power loss so that the inverter can operate at high-temperature conditions while operating at high switching frequencies with small current ripple in low inductance based permanent magnet motors. The proposed tasks also include high-temperature packaging and thermal modeling and simulation to ensure the packaged module can operate at the desired temperature. The developed module will be integrated with the motor and vehicle controller for dynamometer and in-vehicle testing to prove its superiority. This report will describe the detailed technical design of the soft-switching inverters and their test results. The experiments were conducted both in module level for the module conduction and switching characteristics and in inverter level for its efficiency under inductive and dynamometer load conditions. The performance will be compared with the DOE original specification.