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Field Measurements of Heating System Efficiency in Nine Electrically-Heated Manufactured Homes.

Description: This report presents the results of field measurements of heating efficiency performed on nine manufactured homes sited in the Pacific Northwest. The testing procedure collects real-time data on heating system energy use and heating zone temperatures, allowing direct calculation of heating system efficiency.
Date: July 1, 1996
Creator: Davis, Bob; Siegel, J.; Palmiter, L. & Baylon, D.
Partner: UNT Libraries Government Documents Department

Electric co-heating in the ASHRAE standard method of test for thermal distribution efficiency: Test results on two New York State homes

Description: Electric co-heating tests on two single-family homes with forced-air heating systems were carried out in March 1995. The goal of these tests was to evaluate procedures being considered for incorporation in a Standard Method of Test for thermal distribution system efficiency now being developed by ASHRAE. Thermal distribution systems are the ductwork, piping, or other means used to transport heat or cooling effect from the building equipment that produces this thermal energy to the spaces in which it is used. Furthering the project goal, the first objective of the tests was to evaluate electric co-heating as a means of measuring system efficiency. The second objective was to investigate procedures for obtaining the distribution efficiency, using system efficiency as a base. Distribution efficiencies of 0.63 and 0.70 were obtained for the two houses.
Date: October 1, 1995
Creator: Andrews, J.W.; Krajewski, R.F. & Strasser, J.J.
Partner: UNT Libraries Government Documents Department

Design and characterization of microscale heater structures for test die and sensor applications

Description: The authors describe a class of microscale heaters fabricated with CMOS processes on silicon wafers. These heaters were designed to produce localized high temperatures above 400 C for test and sensor applications. The temperature levels produced for various input powers and the thermal profiles surrounding the heater for packaged and wafer-level heater structures were studied to guide the placement of microelectronics integrated with the heater structures on the same die. To show the performance of the design, they present resistance sensor measurements, IR temperature profiles, and results from a 3D thermal model of the die. This effort demonstrates that it is possible to successfully operate both a microscale heater and microcircuits on the same die.
Date: May 1, 1998
Creator: Benson, D.A.; Bowman, D.; Filter, W.; Mitchell, R. & Perry, J.
Partner: UNT Libraries Government Documents Department

Comparison of an impedance heating system to mineral insulated heat trace for power tower applications

Description: A non-conventional type of heating system is being tested at Sandia National Laboratories for solar thermal power tower applications. In this system, called impedance heating, electric current flows directly through the pipe to maintain the desired temperature. The pipe becomes the resistor where the heat is generated. Impedance heating has many advantages over previously used mineral insulated (MI) heat trace. An impedance heating system should be much more reliable than heat trace cable since delicate junctions and cabling are not used and the main component, a transformer, is inherently reliable. A big advantage of impedance heating is the system can be sized to rapidly heat up the piping to provide rapid response times necessary in cyclic power plants such as solar power towers. In this paper, experimental results from testing an impedance heating system are compared to MI heat trace. The authors found impedance heating was able to heat piping rapidly and effectively. There were not significant stray currents and impedance heating did not affect instrumentation.
Date: March 1, 1997
Creator: Pacheco, J.E. & Kolb, W.J.
Partner: UNT Libraries Government Documents Department

Parametric assessments of current rampup by Lower Hybrid Current Drive in TFCX

Description: A lower hybrid current drive code has been developed from two previous existing codes which incorporates the eikonal (WKB) approximation in toroidal canonical variables and an analytic treatment of quasi-linear absorption. Ray-tracing is performed for a 5 to 9 ray spectrum in a nonuniform, circular plasma with the local warm plasma dispersion relation. A parameter study in n/sub e/, T/sub e/, n/sub parallel/, and frequency is being carried out for two startup scenarios (i.e., expanding radius at the outboard midplane and full radius startup on the toroidal axis) for the superconducting toroidal field coil TFCX device. Driven current profiles and current drive efficiencies for both a Maxwellian background plasma and an electron distribution with an rf-enhanced tail are presented.
Date: January 1, 1984
Creator: Freije, S.A. & Peng, Y.K.M.
Partner: UNT Libraries Government Documents Department

Testing and analysis of the Semiscale Mod-1 heater rod design

Description: The use of electrically heated nuclear fuel rod simulators in the Semiscale Program is traced from a historical viewpoint. The design of the Semiscale Mod-1 electrical heater rod and core simulator is discussed. Heater rod thermal response during transient thermal-hydraulic depressurization experiments conducted in the Mod-1 system, and analysis techniques and tests conducted to help quantify heater rod characteristics and behavior are presented.
Date: January 1, 1980
Creator: Larson, T.K.
Partner: UNT Libraries Government Documents Department

Six phase soil heating. Innovative technology summary report

Description: Six Phase Soil Heating (SPSH) was developed to remediate soils contaminated with volatile and semi-volatile organic compounds. SPSH is designed to enhance the removal of contaminates from the subsurface during soil vapor extraction. The innovation combines an emerging technology, six-phase electric heating, with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation systems for difficult soil and/or contaminate applications. This document describes the technology and reports on field demonstrations conducted at Savannah River and the Hanford Reservation.
Date: April 1, 1995
Partner: UNT Libraries Government Documents Department


Description: All sodium piping and equipment is heat traced to maintain the sodium in a liquid state. The Pipe and Equipment Electrical Heating Control System controls the rate of heat application to sodium piping and equipment during heatup of empty systems prior to filling with sodium and to maintain heat in operating sodium systems. The Pipe and Equipment Electric Heating Control System is designed to aid in detecting malfunctions and failures within the system. The Control portion except for the control thermocouple is electrically independent of the alarm portion, thus providing a more reliable check on the overall system. Instrumentation is modular to provide for easy removal and replacement. Detailed maintenance procedures will be developed as a part of the detail design work and will be included in the Operation and Maintenance Manual. Procurement specifications will call for detailed maintenance and calibration procedures for each type of instrument.
Date: September 11, 1972
Creator: DA, GANTT
Partner: UNT Libraries Government Documents Department

Heater element design for electrically powered heater assemblies

Description: This invention is comprised of an apparatus for electrically simulating a nuclear reactor fuel assembly. It includes a heater assembly having a top end and a bottom end and a plurality of concentric heater tubes having electrical circuitry connected to a power source, and radially spaced from each other. An outer target tube and an inner target tube is concentric with the heater tubes and with each other, and the outer target tube surrounds and is radially spaced from the heater tubes. The inner target tube is surrounded by and radially spaced from the heater tubes and outer target tube. The top of the assembly is generally open to allow for the electrical power connection to the heater tubes, and the bottom of the assembly includes means for completing the electrical circuitry in the heater tubes to provide electrical resistance heating to simulate the power profile in a nuclear reactor. The embedded conductor elements in each heater tube is split into two halves for a substantial portion of its length and provided with electrical isolation such that each half of the conductor is joined at one end and is not joined at the other end.
Date: December 31, 1992
Creator: Berta, V. T.
Partner: UNT Libraries Government Documents Department

Prediction of single-component NAPL behavior for the TEVES Project using T2VOC

Description: Detailed simulations have been performed for the TEVES (Thermal Enhanced Vapor Extraction System) Project using the TOUGH2 code considering air, water, and a single-component NAPL. A critical parameter varied in the simulations is the borehole vacuum which directly affects air flow through the system and indirectly influences soil temperatures and water and NAPL fluid masses. Contaminant migration from the heated zone into the unheated soil can occur if the borehole vacuum, or borehole flow rate, is not sufficient. Under these conditions, evaporation of liquids (water and NAPL) due to the heating can cause flow from the heated zone into the unheated soil. Insufficient air sweep may be indicated by a vapor dominated mass flow rate into the borehole, at least for the present configuration. Sufficient air flow through the heated zone must be provided to contain the contaminants within the heated zone.
Date: April 1, 1995
Creator: Webb, S.W. & Phelan, J.M.
Partner: UNT Libraries Government Documents Department

Thermal simulation and economic assessment of unglazed transpired collector systems

Description: Unglazed transpired collectors (UTCs) have recently emerged as a new solar air heating technology. They are relatively inexpensive, efficient, and particularly suited to applications in which a high outdoor air requirement must be met. A TRNSYS model has been created for UTC systems. Annual simulations are performed for several representative buildings. The statewide economic potential of UTC systems is assessed for Wisconsin. UTC systems on existing buildings are competitive with electric heating systems but not with gas or oil heating. Electric heating is not widely used in most buildings that are well-suited for UTC systems, with the exception of large apartment buildings. Therefore, there is no significant statewide economic potential for retrofit of UTC systems on existing buildings except in the residential sector. However, UTC systems are cost effective for new buildings because their low first cost allows them to compete with gas and oil heating.
Date: October 1, 1996
Creator: Summers, D.N.; Mitchell, J.W.; Klein, S.A. & Beckman, W.A.
Partner: UNT Libraries Government Documents Department

State-of-the-Art in Residential and Small Commercial Air HandlerPerformance

Description: Although furnaces, air conditioners, and heat pumps have become significantly more efficient over the last couple of decades, residential air handlers have typical efficiencies of only 10% to 15% due to poor electric motor and aerodynamic performance. These low efficiencies indicate that there is significant room for improvement of air handler fans. The other 85-90% of the electricity used by air handlers is manifested as heat. This extra heat reduces air conditioning cooling and dehumidification performance and effectively acts as fuel switching for fossil fueled furnaces. For electric furnaces, this heat substitutes directly for the electric resistance heating elements. For heat pumps, this heat substitutes for compressor-based high COP heating and effectively reduces the COP of the heat pump. Using a combination of field observations and engineering judgment they can assemble a list of the problems that lead to low air handler efficiency and potential solutions to these problems, as shown. None of the problems require exotic or complex solutions and there are no technological barriers to adopting them. Some of the solutions are simple equipment swaps (using better electric motors), others require changes to the way the components are built (tighter tolerances) and other relate to HVAC equipment design (not putting large fans in small cabinets).
Date: March 1, 2005
Creator: Walker, Iain S.
Partner: UNT Libraries Government Documents Department

Railgun conductor heating from multiple current pulses

Description: A numerical technique for solving current- and thermal-diffusion problems in railgun conductors has been used to study joule heating in rails that are subject to multiple current pulses. Copper rails that are 25 mm high by the 12.5 mm wide with a 20-mm-square bore and a current pulse with 1-MA peak current and 1-ms pulse width at half maximum were assumed. This combination of parameters is sufficient to accelerate an 80-g projectile to 2-3 km/s with which current pulse. Three parameters were varied in the analysis: the repetition rate or current pulse frequency (3.3 to 100 Hz), the coolant heat-transfer coefficient (5 x 10/sup 4/ and 5 x 10/sup 5/ W/m/sup 2/ .K), and the coolant channel distribution in the rail. Detailed results are used to illustrate the acceptability or unacceptability of particular combinations of these parameters for operation at steady state. An uncooled rail was not acceptable for steady-state operation. Repetition rates of about 30 Hz were acceptable with the higher coolant heat-transfer coefficient and the best coolant-channel distribution; this included cooling the rail exterior surface.
Date: January 1, 1986
Creator: Kerrisk, J.F.
Partner: UNT Libraries Government Documents Department

Field Measurements of Heating Efficiency of Electric Forced-Air Furnaces in Six Manufactured Homes.

Description: This report presents the results of field measurements of heating efficiency for six manufactured homes in the Pacific Northwest heated with electric forced-air systems. This is the first in a series of regional and national efforts to measure in detail the heating efficiency of manufactured homes. Only six homes were included in this study because of budgetary constraints; therefore this is not a representative sample. These investigations do provide some useful information on the heating efficiency of these homes. Useful comparisons can be drawn between these study homes and site-built heating efficiencies measured with a similar protocol. The protocol used to test these homes is very similar to another Ecotope protocol used in the study conducted in 1992 and 1993 for the Bonneville Power Administration to test the heating efficiency of 24 homes. This protocol combined real-time power measurements of furnace energy usage with energy usage during co-heat periods. Accessory data such as house and duct tightness measurements and tracer gas measurements were used to describe these homes and their heating system efficiency. Ensuring that manufactured housing is constructed in an energy and resource efficient manner is of increasing concern to manufactured home builders and consumers. No comparable work has been done to measure the heating system efficiency of MCS manufactured homes, although some co-heat tests have been performed on manufactured homes heated with natural gas to validate HUD thermal standards. It is expected that later in 1994 more research of this kind will be conducted, and perhaps a less costly and less time-consuming method for testing efficiencies will be develops.
Date: July 26, 1994
Creator: Davis, Bob; Palmiter, Larry S. & Siegel, Jeff
Partner: UNT Libraries Government Documents Department

Spent-fuel dry-storage testing at E-MAD (March 1978-March 1982)

Description: From March 1978 through March 1982, spent fuel dry storage tests were conducted at the Engine Maintenance, Assembly and Disassembly (E-MAD) facility on the Nevada Test Site to confirm that commercial reactor spent fuel could be encapsulated and passively stored in one or more interim dry storage cell concepts. These tests were: electrically heated drywell, isolated and adjacent drywell, concrete silo, fuel assembly internal temperature measurement, and air-cooled vault. This document presents the test data and results as well as results from supporting test operations (spent fuel calorimetry and canister gas sampling).
Date: September 1, 1982
Creator: Unterzuber, R.; Milnes, R.D.; Marinkovich, B.A. & Kubancsek, G.M.
Partner: UNT Libraries Government Documents Department


Description: In 1991, US and Polish officials signed a Memorandum of Understanding formally initiating and directing the Cracow Clean Fossil Fuels and Energy Efficiency Program. Developing a program approach for the most effective use of the available funds required considerable effort on the part of all project participants. The team recognized early that the cost of solving the low emissions problem even in only one city far exceeded the amount of available US funds. Economic conditions in Poland limited availability of local capital funds for environmental projects. Imposing environmental costs on struggling companies or city residents under difficult conditions of the early 1990's required careful consideration of the economic and political impacts. For all of these reasons the program sought to identify technologies for achieving air quality goals which, through improved efficiency and/or reduced fuel cost, could be so attractive economically as to lead to self-sustaining activities beyond the end of the formal project. The effort under this program has been focused into 5 main areas of interest as follows: (1) Energy Conservation and Extension of Central Station District Heating; (2) Replacement of Coal- and Coke-Fired Boilers with Natural Gas-Fired Boilers; (3) Replacement of Coal-Fired Home Stoves with Electric Heating Appliances; (4) Reduction of Emissions from Stoker-Fired Boiler Houses; and (5) Reduction of Emissions from Coal-Fired Home Heating Stoves.
Date: November 5, 1998
Partner: UNT Libraries Government Documents Department

Energy losses in conductors carrying very high currents

Description: Conductors carrying very high currents show losses of an electromagnetic and a shock compression nature. Electromagnetic losses (joule heating in the skin layer, magnetic flux diffusion) scale as H/sup 3/ or (I/a)/sup 3/, where H is the self magnetic field of the current and I/a is the current divided by conductor - periphery; shock losses scale as H/sup 4/ or H/sup 3/ ((I/a)/sup 4/ or (I/a)/sup 3/) depending on the magnitude of I. In experiments where electrical energy must be converged from a large pulsed power supply to a small load, these losses can account for half the orignal energy and limit the magnitude of the energy per unit volume in the load. These considerations may be important for the study of material properties at high energy density.
Date: January 1, 1981
Creator: Singer, S. & Hunter, R.O.
Partner: UNT Libraries Government Documents Department

Stable Heating and Burn Simulations of a Reversed-Field Pinch Reactor

Description: The reversed-field pinch provides three significant advantages as a fusion reactor: it can be ohmically heated, it operates at high ..beta.., and it is not restricted to a small aspect ratio. Experimentally, the best understood startup scenarios are self reversal, aided reversal and fast-field programming. On the basis of results from a one-dimensional transport and stability code, an ideal MHD stable startup and burn procedure is described in this paper. Pitch programming and a gas feed at the wall are used. This adiabatic startup is characterized by a high pitch near the minor axis and hollow current and pressure profiles. Ideally, it would be possible to have a reactor startup and burn without highly turbulent processes to deposit excessive amounts of energy on the wall Potential problems of resistive instabilities and plasma-wall interactions are discussed.
Date: January 1, 1980
Creator: Moses, R. W., Jr.; Nebel, R. A. & Miley, G. H.
Partner: UNT Libraries Government Documents Department

Advanced performance fusion engineering device based on low safety factor and current drive (FED-A)

Description: The FED-A study aims to quantify the potential improvement in cost-effectiveness of the Fusion Engineering Device (FED) by assuming low safety factor q at the plasma edge and noninductive current drive. The FED-A performance objectives (ignition, neutron wall load, and power-reactor-like operation) are set to be equal to or better than those of the FED Baseline. The results show that assuming magnetohydrodynamic (MHD) q/sub psi/ (edge) to be 1.8 permits reduction in device size and plasma current and leads to a 30% reduction in direct cost. A closely fitted, 1.5-cm-thick, continuous water-cooled shell made of the copper alloy AMAX-MZC (0.6 Cr, 0.1 Zr, 0.03 Mg) is proposed to provide a 0.5-s time constant, to help avoid disruption when q/sub psi/ passes near 2, and to mitigate disruption impact. The lower hybrid wave current drive in a cyclic density operation is proposed to achieve a quasi-steady-state operation permitting a design with low toroidal loop voltage and a 1000-s burn time.
Date: January 1, 1983
Creator: Peng, Y.K.M. & Rutherford, P.H.
Partner: UNT Libraries Government Documents Department

Confinement requirements for ohmic-compressive ignition of a Spheromak plasma

Description: The Moving Plasmoid Reactor (MPR) is an attractive alternative magnetic fusion scheme in which Spheromak plasmoids are envisioned to be formed, compressed, burned, and expanded as the plasmoids translate through a series of linear reactor modules. Although auxiliary heating of the plasmoids may be possible, the MPR scenario would be especially interesting if ohmic decay and compression alone is sufficient to heat the plasmoids to an ignition temperature. In the present work, we examine the transport conditions under which a Spheromak plasmoid can be expected to reach ignition via a combination of ohmic and compression heating.
Date: January 1, 1981
Creator: Olson, R.E. & Miley, G.H.
Partner: UNT Libraries Government Documents Department

Physical and numerical modeling of Joule-heated melters

Description: The Joule-heated ceramic-lined melter is an integral part of the high level waste immobilization process under development by the US Department of Energy. Scaleup and design of this waste glass melting furnace requires an understanding of the relationships between melting cavity design parameters and the furnace performance characteristics such as mixing, heat transfer, and electrical requirements. Developing empirical models of these relationships through actual melter testing with numerous designs would be a very costly and time consuming task. Additionally, the Pacific Northwest Laboratory (PNL) has been developing numerical models that simulate a Joule-heated melter for analyzing melter performance. This report documents the method used and results of this modeling effort. Numerical modeling results are compared with the more conventional, physical modeling results to validate the approach. Also included are the results of numerically simulating an operating research melter at PNL. Physical Joule-heated melters modeling results used for qualiying the simulation capabilities of the melter code included: (1) a melter with a single pair of electrodes and (2) a melter with a dual pair (two pairs) of electrodes. The physical model of the melter having two electrode pairs utilized a configuration with primary and secondary electrodes. The principal melter parameters (the ratio of power applied to each electrode pair, modeling fluid depth, electrode spacing) were varied in nine tests of the physical model during FY85. Code predictions were made for five of these tests. Voltage drops, temperature field data, and electric field data varied in their agreement with the physical modeling results, but in general were judged acceptable. 14 refs., 79 figs., 17 tabs.
Date: October 1, 1985
Creator: Eyler, L.L.; Skarda, R.J.; Crowder, R.S. III; Trent, D.S.; Reid, C.R. & Lessor, D.L.
Partner: UNT Libraries Government Documents Department

Compound sawtooth study in ohmically heated TFTR plasmas

Description: Compound sawtooth activity has been observed in ohmically heated, high current, high density TFTR plasmas. Commonly called ''double sawteeth,'' such sequences consist of a repetitive series of subordinate relaxations followed by a main relaxation with a different inversion radius. The period of such compound sawteeth can be as long as 100 msec. In other cases, however, no compound sawteeth or bursts of them can be observed in discharges with essentially the same parameters.
Date: September 1, 1985
Creator: Yamada, H.; McGuire, K.; Colchin, D.; Efthimion, P.C.; Fredrickson, E.; Hill, K. et al.
Partner: UNT Libraries Government Documents Department

Current drive and heating systems based on high-energy (1- to 3-MeV) negative ion beams

Description: This paper describes a concept for a current drive system based on negative ions with beam energy > 1 MeV. Preliminary physics calculations show that the core current necessary for stability enhancement can best be achieved by beams with energy ranging from 1 to 4 MeV. Further study and experiments will better define the optimum energy. Work under way at Oak Ridge National Laboratory (ORNL) and at collaborating institutes in Canada and the Federal Republic of Germany is defining a system, its elements, a configuration and operational scenarios deemed appropriate for such devices as ITER and other future steady-state tokamaks, and the requisite research and development to provide such a system. 7 refs., 2 figs.
Date: January 1, 1988
Creator: Becraft, W.R.; Akerman, M.A.; Haselton, H.H.; Murphy, B.D.; Lousteau, D.C.; Ryan, P.M. et al.
Partner: UNT Libraries Government Documents Department

Comparison of tokamak burn cycle options

Description: Experimental confirmation of noninductive current drive has spawned a number of suggestions as to how this technique can be used to extend the fusion burn period and improve the reactor prospects of tokamaks. Several distinct burn cycles, which employ various combinations of Ohmic and noninductive current generation, are possible, and we will study their relative costs and benefits for both a commerical reactor as well as an INTOR-class device. We begin with a review of the burn cycle options.
Date: January 1, 1985
Creator: Ehst, D.A.; Brooks, J.N.; Cha, Y.; Evans, K. Jr.; Hassanein, A.M.; Kim, S. et al.
Partner: UNT Libraries Government Documents Department