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1

Efficiency of producing additional power in units of nuclear power stations containing water-cooled-water-moderated reactors  

Microsoft Academic Search

The authors discuss the possibility of raising the maximum power output and fuel efficiency of nuclear power plants using WWER-type reactors by analyzing fuel burnup and reactor kinetics considerations and conclude that this can be achieved by lowering the coefficient of the energy-release nonuniformity in the reactor core. Calculations are presented which describe appropriate safety margins under various peak load

R. Z. Aminov; V. A. Khrustalev; A. A. Serdobintsev; A. S. Dukhovenskii; A. I. Osadchii

1987-01-01

2

BURNUP OF FUEL IN WATER-MODERATED WATER-COOLED POWER REACTORS AND URANIUM WATER LATTICE EXPERIMENTS  

Microsoft Academic Search

The method and the results are reported of numerical calculations of ; fuel burning in ordinary water-cooled and -moderated reactors with a homogeneous ; core which use fresh slightly enriched fuel. The point of departure of the ; method is the notion of stationary conditions at which the process is maintained ; in the reactor as a result of a

S. M. Feinberg; E. S.. Antsiferov

1959-01-01

3

Neutronics analyses of natural uranium fueled, light water cooled, heavy water moderated and graphite reflected nuclear reactors  

Microsoft Academic Search

The work presented in this paper was conducted to validate the computer codes such as WIMS-D\\/4 and CITATION for the criticality analyses of natural uranium fueled, light water cooled, heavy water moderated and graphite reflected reactors such as National Experimental Reactor (NRX) and Canadian Indian Reactor (CIR). These codes are then used to search a proliferation resistant reactor core. It

M. J Khan; Aslam; N Ahmad

2004-01-01

4

Seismicity and seismic response of the Soviet-designed VVER (Water-cooled, Water moderated Energy Reactor) reactor plants  

SciTech Connect

On March 4, 1977, a strong earthquake occurred at Vrancea, Romania, about 350 km from the Kozloduy plant in Bulgaria. Subsequent to this event, construction of the unit 2 of the Armenia plant was delayed over two years while seismic features were added. On December 7, 1988, another strong earthquake struck northwest Armenia about 90 km north of the Armenia plant. Extensive damage of residential and industrial facilities occurred in the vicinity of the epicenter. The earthquake did not damage the Armenia plant. Following this event, the Soviet government announced that the plant would be shutdown permanently by March 18, 1989, and the station converted to a fossil-fired plant. This paper presents the results of the seismic analyses of the Soviet-designed VVER (Water-cooled, Water moderated Energy Reactor) plants. Also presented is the information concerning seismicity in the regions where VVERs are located and information on seismic design of VVERs. The reference units are the VVER-440 model V230 (similar to the two units of the Armenia plant) and the VVER-1000 model V320 units at Kozloduy in Bulgaria. This document provides an initial basis for understanding the seismicity and seismic response of VVERs under seismic events. 1 ref., 9 figs., 3 tabs.

Ma, D.C.; Gvildys, J.; Wang, C.Y.; Spencer, B.W.; Sienicki, J.J.; Seidensticker, R.W.; Purvis, E.E. III

1989-01-01

5

Department of Energy's team's analyses of Soviet designed VVERs (water-cooled water-moderated atomic energy reactors)  

SciTech Connect

This document contains apprendices A through P of this report. Topics discussed are: a cronyms and technical terms, accident analyses reactivity control; Soviet safety regulations; radionuclide inventory; decay heat; operations and maintenance; steam supply system; concrete and concrete structures; seismicity; site information; neutronic parameters; loss of electric power; diesel generator reliability; Soviet codes and standards; and comparisons of PWR and VVER features. (FI)

Not Available

1989-09-01

6

Water Cooling of High Power Light Emitting Diode Henrik Srensen  

E-print Network

becomes comparable in magnitude with e.g. a nuclear reactions [1]. The high rate of heat generatedWater Cooling of High Power Light Emitting Diode Henrik Sørensen Department of Energy Technology light. High power LEDs has problems with low efficiency, and together with a high current this leads

Berning, Torsten

7

Development Project of Supercritical-water Cooled Power Reactor  

Microsoft Academic Search

A Supercritical-water Cooled Power Reactor (SCPR) development project (Feb. 2001- Mar. 2005) is being performed by a joint team consisting of Japanese universities and nuclear venders with a national fund. The main objective of this project is to provide technical information essential to demonstration of SCPR technologies through concentrating three sub-themes: 'plant conceptual design', 'thermohydraulics', and 'material and water chemistry'.

K. Kataoka; S. Shiga; K. Moriya; Y. Oka; S. Yoshida; H. Takahashi

2002-01-01

8

78 FR 64029 - Cost-Benefit Analysis for Radwaste Systems for Light-Water-Cooled Nuclear Power Reactors  

Federal Register 2010, 2011, 2012, 2013

...components for light water nuclear power reactors. ADDRESSES...Burton@nrc.gov, U.S. Nuclear Regulatory Commission, Washington...Technical Direction to Revise Radiation Protection Regulations and...Material in Light-Water-Cooled Nuclear Power Reactor...

2013-10-25

9

Numerical analysis on the beam quality improvements of high power chemical laser system with water cooled mirrors  

Microsoft Academic Search

Chemical laser is one of the most widely used high power infrared sources. Thermal deformation of mirrors in a resonator is a key factor which hinders the improvement of the beam quality in high power chemical lasers, and it has been a matter of the utmost concern in the design of high power chemical laser systems. Water-cooled technique is one

Kai Han; Bin Li; Xiao-Jun Xu

2011-01-01

10

HEAVY WATER MODERATED POWER REACTORS. Quarterly Progress Report for November 1958 through January 1959  

Microsoft Academic Search

Experimental work this quarter in the study of natural-uranium-fueled, D\\/; sub 2\\/O-moderated power reactors featured the successful fabrication of nine ; Zircaloy-clad U-2 wt.% Zr fuel tubes, a major advance in the extrusion of thin-; walled zirconium components, the startup of the high temperature exponential ; facility, continuation of the irradiation testing of prototype fuel elements, and ; additional work

Isakoff

1959-01-01

11

Optimization of power-cycle arrangements for Supercritical Water cooled Reactors (SCWRs)  

NASA Astrophysics Data System (ADS)

The world energy demand is continuously rising due to the increase of both the world population and the standard of life quality. Further, to assure both a healthy world economy as well as adequate social standards, in a relatively short term, new energy-conversion technologies are mandatory. Within this framework, a Generation IV International Forum (GIF) was established by the participation of 10 countries to collaborate for developing nuclear power reactors that will replace the present technology by 2030. The main goals of these nuclear-power reactors are: economic competitiveness, sustainability, safety, reliability and resistance to proliferation. As a member of the GIF, Canada has decided to orient its efforts towards the design of a CANDU-type Super Critical Water-cooled Reactor (SCWR). Such a system must run at a coolant outlet temperature of about 625C and at a pressure of 25 MPa. It is obvious that at such conditions the overall efficiency of this kind of Nuclear Power Plant (NPP) will compete with actual supercritical water-power boilers. In addition, from a heat-transfer viewpoint, the use of a supercritical fluid allows the limitation imposed by Critical Heat Flux (CHF) conditions, which characterize actual technologies, to be removed. Furthermore, it will be also possible to use direct thermodynamic cycles where the supercritical fluid expands right away in a turbine without the necessity of using intermediate steam generators and/or separators. This work presents several thermodynamic cycles that could be appropriate to run SCWR power plants. Improving both thermal efficiency and mechanical power constitutes a multi-objective optimization problem and requires specific tools. To this aim, an efficient and robust evolutionary algorithm, based on genetic algorithm, is used and coupled to an appropriate power plant thermodynamic simulation model. The results provide numerous combinations to achieve a thermal efficiency higher than 50% with a mechanical power of 1200 MW. It is observed that in most cases the landscape of Pareto's front is mostly controlled only by few key parameters. These results may be very useful for future plant design engineers. Furthermore, some calculations for pipe sizing and temperature variation between coolant and fuel have been carried out to provide an idea on their order of magnitude.

Lizon-A-Lugrin, Laure

12

Water-cooled electronics  

Microsoft Academic Search

LHC experiments demand on cooling of electronic instrumentation will be extremely high. A large number of racks will be located in underground caverns and counting rooms, where cooling by conventional climatisation would be prohibitively expensive. A series of tests on the direct water cooling of VMEbus units and of their standard power supplies is reported. A maximum dissipation of 60W

G. Dumont; Ph. Fontaine Vive Roux; B. Righini

2000-01-01

13

Water-cooled grid support for high-power irradiation with thin target windows  

Microsoft Academic Search

A new thin window support system for the accelerator production of positron emitters (e.g. 17F, 18F 11C, 15O) has been developed. The integrated support grid and cooling design has been optimized for 613MeV protons or deuterons. The water-cooled support grid regularly operated at >100?A of 6MeV deuterons and protons. The grid performed without failure at ?50?A of 13MeV protons on

T. E Barnhart; A. K Converse; K. A Dabbs; R. J Nickles; K Buckley; S Jivan; T. J Ruth; A. D Roberts

2003-01-01

14

Hydraulic design of a re-circulating water cooling system of a combined cycle power plant in Thailand  

SciTech Connect

The paper describes the hydraulic design and hydraulic transient analysis of the re-circulating water cooling system of the combined cyclo Sipco power cogeneration plant in Thailand. The power plant of 450 MW total capacity is proposed to be built in two stages. Stage one will produce 300 MW of power and will consist of two gas turbine generators (GTG) and one steam turbine generator (STG). Stage two will produce 150 MW of power and will consist of one GTG and one STG. The cooling system will consist of one GTG and one STG. The cooling system will consist of cooling towers, a combined collecting basin and pump intake sump, pumps and motors, and separate conveyance systems and condensers for the generator units in the two stages. In a re-circulating water cooling system, cold water is pumped from the pump intake sump to the condensers through the conveyance system and hot water from the condensers is carried through the returning pipeline system to the cooling towers, whence the water after cooling is drained into the sump at the base of the towers. Total cooling water requirement for the system in stage one is estimated to be 112,000 gallons per minute (GPM), and that in stage two, 56,000 GPM. The sump is designed using the computer program HEC-2, developed by the US Army Corps of Engineers (COE) and the pump intake basin, following the recommendations of the Hydraulic Institute. The pumps were sized by computing the head loss in the system, and, the steady state and transient performances (during pump start-up and shut-down procedures and due to possible power or mechanical failure of one or all pumps) of the system were analyzed by mathematically modeling the system using the computer program WHAMO (Water Hammer nd Mass Oscillations), also developed by the COE.

Sarkar, C.K.; Pandit, D.R. [Parsons Infrastructure and Technology Group, Boston, MA (United States); Kwon, S.G. [Kolon Engineering and Construction Co., Ltd., Seoul (Korea, Republic of)

1998-12-31

15

Water-cooled 2kW calorimeter for laser power measurement. Final report  

Microsoft Academic Search

To meet the growing need for reliable monitoring of industrial high-power CO lasers, a calorimeter was designed to be both easily used, reliable, and accurate. A maximum continuous power input of 2 kilowatts was specified in order to handle commonly used CO lasers. Two different measurement methods are discussed. First results indicate a sensitivity of 7.8 W\\/mV. The 1\\/e response

P. A. Simpson; R. W. Zimmerer

1981-01-01

16

Natural Circulation in Water Cooled Nuclear Power Plants Phenomena, models, and methodology for system reliability assessments  

SciTech Connect

In recent years it has been recognized that the application of passive safety systems (i.e., those whose operation takes advantage of natural forces such as convection and gravity), can contribute to simplification and potentially to improved economics of new nuclear power plant designs. In 1991 the IAEA Conference on ''The Safety of Nuclear Power: Strategy for the Future'' noted that for new plants the use of passive safety features is a desirable method of achieving simplification and increasing the reliability of the performance of essential safety functions, and should be used wherever appropriate''.

Jose Reyes

2005-02-14

17

Feasibility Study of Supercritical Light Water Cooled Fast Reactors for Actinide Burning and Electric Power Production  

SciTech Connect

The use of supercritical temperature and pressure light water as the coolant in a direct-cycle nuclear reactor offers potential for considerable plant simplification and consequent capital and O&M cost reduction compared with current light water reactor (LWR) designs. Also, given the thermodynamic conditions of the coolant at the core outlet (i.e. temperature and pressure beyond the water critical point), very high thermal efficiencies of the power conversion cycle are possible (i.e. up to 46%). Because no change of phase occurs in the core, the need for steam separators and dryers as well as for BWR-type recirculation pumps is eliminated, which, for a given reactor power, results in a substantially shorter reactor vessel than the current BWRs. Furthermore, in a direct cycle the steam generators are not needed. If a tight fuel rod lattice is adopted, it is possible to significantly reduce the neutron moderation and attain fast neutron energy spectrum conditions. In this project a supercritical water reactor concept with a simple, blanket-free, pancake-shaped core will be developed. This type of core can make use of either fertile or fertile-free fuel and retain the hard spectrum to effectively burn plutonium and minor actinides from LWR spent fuel while efficiently generating electricity.

Mac Donald, Philip Elsworth; Buongiorno, Jacopo; Davis, Cliff Bybee; Weaver, Kevan Dean

2002-01-01

18

ADVANCED COURSE ON FUEL ELEMENTS FOR WATER COOLED POWER REACTORS, ORGANIZED BY THE NETHERLANDS'NORWEGIAN REACTOR SCHOOL AT INSTITUTT FOR ATOMENERGI, KJELLER, NORWAY, 22nd AUGUST3rd SEPTEMBER,1960. VOLUME III  

Microsoft Academic Search

A series of lectures on fuel elements for water-cooled power reactors are presented. Topics covered include fabrication, properties, cladding, radiation damage, design, cycling, storage and transpont, and reprocessing. Separate records have been prepared for each section.

S. Aas; T. J. Barendregt; A. Chesne; J. M. Fletcher; K. P. Lindland

1960-01-01

19

Some neutron-physics considerations of improving the fuel use in water-cooled thermal vver and RBMK power reactors  

SciTech Connect

The exploitation of the fuel in water-cooled reactors can be improved by changing the design and the operational conditions of the reactor and also by replacing in those reactors the uranium dioxide by other types of fuel, e.g., by uranium fuel of increased density. In the modernization of reactors (without fuel replacement) one can reduce the consumption of natural uranium fed to the reactor in stationary operation by about 20%. A method is presented of calculating the conversion coefficient and the neutron balance. Results are presented.

Lyovina, I.K.; Sidorenko, V.A.

1986-10-01

20

Feasibility Study of Supercritical Light Water Cooled Reactors for Electric Power Production, Progress Report for Work Through September 2003, 2nd Annual/8th Quarterly Report  

SciTech Connect

The supercritical water-cooled reactor (SCWR) is one of the six reactor technologies selected for research and development under the Generation-IV program. SCWRs are promising advanced nuclear systems because of their high thermal efficiency (i.e., about 45% vs. about 33% efficiency for current Light Water Reactors, LWRs) and considerable plant simplification. SCWRs are basically LWRs operating at higher pressure and temperatures with a direct once-through cycle. Operation above the critical pressure eliminates coolant boiling, so the coolant remains single-phase throughout the system. Thus the need for recirculation and jet pumps, a pressurizer, steam generators, steam separators and dryers is eliminated. The main mission of the SCWR is generation of low-cost electricity. It is built upon two proven technologies, LWRs, which are the most commonly deployed power generating reactors in the world, and supercritical fossil-fired boilers, a large number of which is also in use around the world.

Philip E. MacDonald

2003-09-01

21

Water cooled steam jet  

DOEpatents

A water cooled steam jet for transferring fluid and preventing vapor lock, or vaporization of the fluid being transferred, has a venturi nozzle and a cooling jacket. The venturi nozzle produces a high velocity flow which creates a vacuum to draw fluid from a source of fluid. The venturi nozzle has a converging section connected to a source of steam, a diffuser section attached to an outlet and a throat portion disposed there between. The cooling jacket surrounds the venturi nozzle and a suction tube through which the fluid is being drawn into the venturi nozzle. Coolant flows through the cooling jacket. The cooling jacket dissipates heat generated by the venturi nozzle to prevent vapor lock. 2 figs.

Wagner, E.P. Jr.

1999-01-12

22

10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors  

Code of Federal Regulations, 2011 CFR

...containment of direct-cycle boiling water power reactors. ...to the Total time and Point-to-Point methods described...isolation valve seal-water system fluid inventory...secondary containments for boiling water reactors and shield...

2011-01-01

23

10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors  

Code of Federal Regulations, 2013 CFR

...containment of direct-cycle boiling water power reactors. ...to the Total time and Point-to-Point methods described...isolation valve seal-water system fluid inventory...secondary containments for boiling water reactors and shield...

2013-01-01

24

10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors  

Code of Federal Regulations, 2010 CFR

10 Energy 1 2010-01-01...Appendix J to Part 50 Energy NUCLEAR REGULATORY COMMISSION...for other types of nuclear power reactors...radioactivity to the environment. B. Containment...controls intended to effect containment...

2010-01-01

25

Water cooled garments: A review  

Microsoft Academic Search

Water cooled garments have found a variety of applications in aerospace and industrial settings since 1962 and the pertinent literature is widely scattered. This review includes a brief look at human thermoregulation followed by a history of water cooled garment (WCG) development and a description of current suits in the U.S. and U.K. Discussion includes variables affecting WCG design and

Sarah A. Nunneley

1970-01-01

26

Feasibility Study of Supercritical Light Water Cooled Fast Reactors for Actinide Burning and Electric Power Production, 3rd Quarterly Report  

SciTech Connect

The use of light water at supercritical pressures as the coolant in a nuclear reactor offers the potential for considerable plant simplification and consequent capital and O&M cost reduction compared with current light water reactor (LWR) designs. Also, given the thermodynamic conditions of the coolant at the core outlet (i.e. temperature and pressure beyond the water critical point), very high thermal efficiencies of the power conversion cycle are possible (i.e. up to about 45%). Because no change of phase occurs in the core, the need for steam separators and dryers as well as for BWR-type re-circulation pumps is eliminated, which, for a given reactor power, results in a substantially shorter reactor vessel and smaller containment building than the current BWRs. Furthermore, in a direct cycle the steam generators are not needed.

Mac Donald, Philip Elsworth

2002-06-01

27

Feasibility Study of Supercritical Light Water Cooled Fast Reactors for Actinide Burning and Electric Power Production, Progress Report for Work Through September 2002, 4th Quarterly Report  

SciTech Connect

The use of light water at supercritical pressures as the coolant in a nuclear reactor offers the potential for considerable plant simplification and consequent capital and O&M cost reduction compared with current light water reactor (LWR) designs. Also, given the thermodynamic conditions of the coolant at the core outlet (i.e. temperature and pressure beyond the water critical point), very high thermal efficiencies of the power conversion cycle are possible (i.e. up to about 45%). Because no change of phase occurs in the core, the need for steam separators and dryers as well as for BWR-type re-circulation pumps is eliminated, which, for a given reactor power, results in a substantially shorter reactor vessel and smaller containment building than the current BWRs. Furthermore, in a direct cycle the steam generators are not needed. If no additional moderator is added to the fuel rod lattice, it is possible to attain fast neutron energy spectrum conditions in a supercritical water-cooled reactor (SCWR). This type of core can make use of either fertile or fertile-free fuel and retain a hard spectrum to effectively burn plutonium and minor actinides from LWR spent fuel while efficiently generating electricity. One can also add moderation and design a thermal spectrum SCWR. The Generation IV Roadmap effort has identified the thermal spectrum SCWR (followed by the fast spectrum SCWR) as one of the advanced concepts that should be developed for future use. Therefore, the work in this NERI project is addressing both types of SCWRs.

Mac Donald, Philip Elsworth

2002-09-01

28

Wetland Water Cooling Partnership: The Use of Constructed Wetlands to Enhance Thermoelectric Power Plant Cooling and Mitigate the Demand of Surface Water Use  

SciTech Connect

Through the Phase I study segment of contract #DE-NT0006644 with the U.S. Department of Energys National Energy Technology Laboratory, Applied Ecological Services, Inc. and Sterling Energy Services, LLC (the AES/SES Team) explored the use of constructed wetlands to help address stresses on surface water and groundwater resources from thermoelectric power plant cooling and makeup water requirements. The project objectives were crafted to explore and develop implementable water conservation and cooling strategies using constructed wetlands (not existing, naturally occurring wetlands), with the goal of determining if this strategy has the potential to reduce surface water and groundwater withdrawals of thermoelectric power plants throughout the country. Our teams exploratory work has documented what appears to be a significant and practical potential for augmenting power plant cooling water resources for makeup supply at many, but not all, thermoelectric power plant sites. The intent is to help alleviate stress on existing surface water and groundwater resources through harvesting, storing, polishing and beneficially re-using critical water resources. Through literature review, development of conceptual created wetland plans, and STELLA-based modeling, the AES/SES team has developed heat and water balances for conventional thermoelectric power plants to evaluate wetland size requirements, water use, and comparative cooling technology costs. The ecological literature on organism tolerances to heated waters was used to understand the range of ecological outcomes achievable in created wetlands. This study suggests that wetlands and water harvesting can provide a practical and cost-effective strategy to augment cooling waters for thermoelectric power plants in many geographic settings of the United States, particularly east of the 100th meridian, and in coastal and riverine locations. The study concluded that constructed wetlands can have significant positive ancillary socio-economic, ecosystem, and water treatment/polishing benefits when used to complement water resources at thermoelectric power plants. Through the Phase II pilot study segment of the contract, the project team partnered with Progress Energy Florida (now Duke Energy Florida) to quantify the wetland water cooling benefits at their Hines Energy Complex in Bartow, Florida. The project was designed to test the wetlands ability to cool and cleanse power plant cooling pond water while providing wildlife habitat and water harvesting benefits. Data collected during the monitoring period was used to calibrate a STELLA model developed for the site. It was also used to inform management recommendations for the demonstration site, and to provide guidance on the use of cooling wetlands for other power plants around the country. As a part of the pilot study, Duke Energy is scaling up the demonstration project to a larger, commercial scale wetland instrumented with monitoring equipment. Construction is expected to be finalized in early 2014.

Apfelbaum, Steven; Duvall, Kenneth; Nelson, Theresa; Mensing, Douglas; Bengtson, Harlan; Eppich, John; Penhallegon, Clayton; Thompson, Ry

2013-09-30

29

Chilled Water Cooling Coil Models from Empirical to Fundamental  

Microsoft Academic Search

Computer simulation is a very powerful tool in the study of heat transfer equipment and process dynamics. In the field of air-conditioning, a range of computer models of cooling coils has been developed. This article gives a brief review of the chilled water cooling coil models introduced in past decades. Following the development trend, it is suggested that while semiempirical

T. T. Chow

1997-01-01

30

Effect of heat release in the coolant on the stability of a water-cooled-water-moderated reactor  

Microsoft Academic Search

The authors use exact kinetic equations in order to estimate the effect of heat release on the coolant. The authors found that the instantaneous release of even an insignificant part of the heat in the coolant exerts a significant stabilizing effect on the stability of a boiling reactor, especially in the case of a high steam content at the core

S. I. Vdovin; E. F. Sabaev

1985-01-01

31

Electrochemistry of Water-Cooled Nuclear Reactors  

SciTech Connect

This project developed a comprehensive mathematical and simulation model for calculating thermal hydraulic, electrochemical, and corrosion parameters, viz. temperature, fluid flow velocity, pH, corrosion potential, hydrogen injection, oxygen contamination, stress corrosion cracking, crack growth rate, and other important quantities in the coolant circuits of water-cooled nuclear power plants, including both Boiling Water Reactors (BWRs) and Pressurized Water Reactors (PWRs). The model is being used to assess the three major operational problems in Pressurized Water Reactors (PWR), which include mass transport, activity transport, and the axial offset anomaly, and provide a powerful tool for predicting the accumulation of SCC damage in BWR primary coolant circuits as a function of operating history. Another achievement of the project is the development of a simulation tool to serve both as a training tool for plant operators and as an engineering test-bed to evaluate new equipment and operating strategies (normal operation, cold shut down and others). The development and implementation of the model allows us to estimate the activity transport or "radiation fields" around the primary loop and the vessel, as a function of the operating parameters and the water chemistry.

Dgiby Macdonald; Mirna Urquidi-Macdonald; John Mahaffy, Amit Jain, Han Sang Kim, Vishisht Gupta; Jonathan Pitt

2006-08-08

32

Stability analysis of supercritical water cooled reactors  

E-print Network

The Supercritical Water-Cooled Reactor (SCWR) is a concept for an advanced reactor that will operate at high pressure (25MPa) and high temperature (500C average core exit). The high coolant temperature as it leaves the ...

Zhao, Jiyun, Ph. D. Massachusetts Institute of Technology

2005-01-01

33

Feasibility Study of Supercritical Light Water Cooled Fast Reactors for Actinide Burning and Electric Power Production Progress Report for Year 1, Quarter 2 (January - March 2002)  

SciTech Connect

The use of light water at supercritical pressures as the coolant in a nuclear reactor offers the potential for considerable plant simplification and consequent capital and O&M cost reduction compared with current light water reactor (LWR) designs. Also, given the thermodynamic conditions of the coolant at the core outlet (i.e. temperature and pressure beyond the water critical point), very high thermal efficiencies of the power conversion cycle are possible (i.e. up to about 45%). Because no change of phase occurs in the core, the need for steam separators and dryers as well as for BWR-type re-circulation pumps is eliminated, which, for a given reactor power, results in a substantially shorter reactor vessel and smaller containment building than the current BWRs. Furthermore, in a direct cycle the steam generators are not needed.

Mac Donald, Philip Elsworth; Buongiorno, Jacopo; Davis, Cliff Bybee; Weaver, Kevan Dean

2002-03-01

34

Preliminary studies on the heat exchanger option for S-CO{sub 2} power conversion cycle coupled to water cooled SMR  

SciTech Connect

For more than a half century, the steam Rankine cycle had been the major power conversion cycle for a nuclear power plant. However, as the interest on the next generation reactors grows, a variety of alternative power conversion systems have been studied. Among them, the S-CO{sub 2} cycle (Supercritical carbon dioxide Brayton cycle) is considered as a promising candidate due to several benefits such as 1) Relatively high thermal efficiency at relatively low turbine inlet temperature, 2) High efficiency with simple lay-out 3) Compactness of turbo-machineries. 4) Compactness of total cycle combined with PCHE (Printed Circuit Heat Exchanger). According to the conventional classification of heat exchangers (HE), there are three kind of HE, 1) Tubular HEs, 2) Plate-type HEs, 3) Extended surface HEs. So far, the researcher has mostly assumed PCHE type HE for the S-CO{sub 2} cycle due to its compactness with reasonably low pressure drop. However, PCHE is currently one of the most expensive components in the cycle, which can have a negative effect on the economics of the cycle. Therefore, an alternative for the HE should be seriously investigated. By comparing the operating condition (pressure and temperature) there are three kind of HE in the S-CO{sub 2} cycle, 1) IHX (Intermediate Heat exchanger) 2) Recuperator and 3) Pre-cooler. In each heat exchanger, hot side and cold side coolants are different, i.e. reactor coolant to S-CO{sub 2} (IHX), S-CO{sub 2} to S-CO{sub 2}(Recuperator), S-CO{sub 2} to water (Pre-cooler). By considering all the attributes mentioned above, all existing types of heat exchangers are compared to find a possible alternative to PCHE. The comparing factors are 1) Size(volume), 2) Cost. Plate fin type HEs are considered to be the most competitive heat exchanger regarding the size and the cost after some improvements on the design limit are made. (authors)

Ahn, Y.; Lee, J. [Dept. of Nuclear and Quantum Engineering, Korea Advanced Inst. of Science and Technology, 373-1 Guseong-dong Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Lee, J. I. [Dept. of Nuclear and Quantum Engineering, Korea Advanced Inst. of Science and Technology, 373-1 Guseong-dong Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Dept. of Nuclear Engineering, Khalifa Univ. of Science, Technology and Research (KUSTAR), P.O.Box 127788, Abu Dhabi (United Arab Emirates)

2012-07-01

35

Water cooling considerations for the SSC  

SciTech Connect

The purpose of this note is to specify parameters for hypothetical SSC water cooling systems, in order that the comparative advantages of these system can be studied. The various methods of heat rejection considered include: cooling towers, cooling ponds, ground water recharge system, water-to-air (dry) cooling towers, use of tunnel sump water, or some combination.

O'Meara, J.

1984-11-02

36

Thermal hydraulics of water cooled divertors  

Microsoft Academic Search

Divertors of several new machines, such as JT-60SU, FIRE, SST-1, ITER-RC and KSTAR, are water-cooled. This paper examines critical thermal hydraulic issues associated with the design of such divertors. The flow direction of coolant in the divertor can be either toroidal or poloidal. A quantitative evaluation shows that the poloidal flow direction is preferred, because the flow rate and pumping

C. B Baxi

2001-01-01

37

Feasibility Study of Supercritical Light Water Cooled Reactors for Electric Power Production, Nuclear Energy Research Initiative Project 2001-001, Westinghouse Electric Co. Grant Number: DE-FG07-02SF22533, Final Report  

SciTech Connect

The supercritical water-cooled reactor (SCWR) is one of the six reactor technologies selected for research and development under the Generation IV program. SCWRs are promising advanced nuclear systems because of their high thermal efficiency (i.e., about 45% versus about 33% efficiency for current Light Water Reactors [LWRs]) and considerable plant simplification. SCWRs are basically LWRs operating at higher pressure and temperatures with a direct once-through cycle. Operation above the critical pressure eliminates coolant boiling, so the coolant remains single-phase throughout the system. Thus, the need for a pressurizer, steam generators, steam separators, and dryers is eliminated. The main mission of the SCWR is generation of low-cost electricity. It is built upon two proven technologies: LWRs, which are the most commonly deployed power generating reactors in the world, and supercritical fossil-fired boilers, a large number of which are also in use around the world. The reference SCWR design for the U.S. program is a direct cycle system operating at 25.0 MPa, with core inlet and outlet temperatures of 280 and 500 C, respectively. The coolant density decreases from about 760 kg/m3 at the core inlet to about 90 kg/m3 at the core outlet. The inlet flow splits with about 10% of the inlet flow going down the space between the core barrel and the reactor pressure vessel (the downcomer) and about 90% of the inlet flow going to the plenum at the top of the rector pressure vessel, to then flow down through the core in special water rods to the inlet plenum. Here it mixes with the feedwater from the downcomer and flows upward to remove the heat in the fuel channels. This strategy is employed to provide good moderation at the top of the core. The coolant is heated to about 500 C and delivered to the turbine. The purpose of this NERI project was to assess the reference U.S. Generation IV SCWR design and explore alternatives to determine feasibility. The project was organized into three tasks: Task 1. Fuel-cycle Neutronic Analysis and Reactor Core Design Task 2. Fuel Cladding and Structural Material Corrosion and Stress Corrosion Cracking Task 3. Plant Engineering and Reactor Safety Analysis. moderator rods. materials.

Philip E. MacDonald

2005-01-01

38

Corrosion behavior of Ni-base alloys for advanced high temperature water-cooled nuclear plants  

Microsoft Academic Search

Due to the projected requirement for highly enhanced efficiency in power generation, the environment in advanced high temperature water-cooled nuclear systems becomes more rigorous compared to conventional fossil and nuclear power plants. The corrosion behavior of candidate alloys Inconel 617, 625, and 718 exposed to supercritical water was studied by a variety of analytical techniques. Grain boundary engineering (GBE) was

L. Tan; X. Ren; K. Sridharan; T. R. Allen

2008-01-01

39

Advanced water-cooled phosphoric acid fuel cell development  

NASA Astrophysics Data System (ADS)

The Advanced Water Cooled Phosphoric Acid Fuel Cell Development Program is being conducted by International Fuel Cells Corporation (IFC) to improve the performance and minimize the cost of water-cooled, electric utility phosphoric acid fuel cell stacks. The program adapts the existing on-site Configuration B cell design to electric utility operating conditions and introduces additional new design features. Task 1 consists of the conceptual design of a full-scale electric utility cell stack that meets program objectives. Tasks 2 and 3 develop the materials and processes required to fabricate the components that meet the program objective. The design of the small area and two 10-ft(exp 2) short stacks is conducted in task 4. The conceptual design also is updated to incorporate the results of material and process developments, as well as results of stack tests conducted in task 6. Fabrication and assembly of the short stacks are conducted in task 5 and subsequent tests are conducted in task 6. The Contractor expects to enter into a contract with the Electric Power Research Institute (EPRI) to assemble and endurance test the second 10-ft(exp 2) short stack. The management and reporting functions of task 7 provide DOE/METC with program visibility through required documentation and program reviews. This report describes the cell design and development effort that is being conducted to demonstrate, by subscale stack test, the technical achievements made toward the above program objectives.

1992-07-01

40

A non-water-cooled heat flux measurement system under concentrated solar radiation conditions  

Microsoft Academic Search

This paper presents a brief description of a direct heat flux measurement system to measure the concentrated solar power delivered by a heliostat field onto the flat aperture of solar central receiver prototypes. The main advantages of this device are the low measurement uncertainty and the non-requirement of water-cooling. This system has been designed, mounted and used successfully on top

Jesus Ballestrin

2002-01-01

41

Numerical analysis of heat transfer in supercritical water cooled flow channels  

Microsoft Academic Search

Research activities are ongoing worldwide to develop nuclear power plants with a supercritical water cooled reactor (SCWR) with the purpose to achieve a high thermal efficiency and to improve their economical competitiveness. However, there is still a big deficiency in understanding and prediction of heat transfer in supercritical fluids. In this paper, heat transfer of supercritical water has been investigated

X. Cheng; B. Kuang; Y. H. Yang

2007-01-01

42

Supercritical-pressure, light-water-cooled reactors for improving economy, safety, plutonium utilization and environment  

Microsoft Academic Search

The concepts of a direct-cycle supercritical-pressure, light-water-cooled reactors were developed. The conceptual design of the thermal and fast reactors was carried out. The plant system is identical among them. Breeding is possible in the tight lattice core. Waste problems are improved due to the high thermal efficiency. Power generation cost will be greatly reduced from the current LAIR.

Y Oka; S Koshizuka; T Jevremovic; Y Okano

1995-01-01

43

Conceptual design of compact supercritical water-cooled fast reactor with thermal hydraulic coupling  

Microsoft Academic Search

Fuel rod design for high power density supercritical water-cooled fast reactor was conducted with mixed-oxide (MOX) fuel and stainless steel (SUS304) cladding under the limiting cladding surface temperature of 650C. Fuel and cladding integrities, and flow-induced vibration were taken into account as design criteria. Designed fuel rod has the diameter of 7.6mm and is arranged in the fuel assembly with

Jaewoon Yoo; Yuki Ishiwatari; Yoshiaki Oka; Jie Liu

2006-01-01

44

Advanced water-cooled phosphoric acid fuel cell development  

NASA Astrophysics Data System (ADS)

This program is being conducted to improve the performance and minimize the cost of water cooled, electric utility phosphoric acid fuel cell stacks. The program adapts the existing on-site Configuration B cell design to electric utility operating conditions and introduces additional new design features. Task 1 consists of the conceptual design of a full-scale electric utility cell stack that meets program objectives. Tasks 2 and 3 develop the materials and processes requested to fabricate the components that meet the program objective. The design of the small area and two 10-ft(exp 2) short stacks is conducted in Task 4. The conceptual design also is updated to incorporate the results of material and process developments, as well as results of stack tests conducted in Task 6. Fabrication and assembly of the short stacks are conducted in Task 5 and subsequent tests are conducted in Task 6. The Contractor expects to enter into a contract with the Electric Power Research Institute (EPRI) to assemble and endurance test the second 10-ft(exp 2) short stack. The management and reporting functions of Task 7 provide DOE/METC with program visibility through required documentation and program reviews. This report describes the cell design and development effort that is being conducted to demonstrate, by subscale stack test, the technical achievements made toward the above program objectives.

1992-05-01

45

Advanced water-cooled phosphoric acid fuel cell development  

NASA Astrophysics Data System (ADS)

This program was conducted to improve the performance and minimize the cost of existing water-cooled phosphoric acid fuel cell stacks for electric utility and on-site applications. The goals for the electric utility stack technology were a power density of at least 175 watts per square foot over a 40,000-hour useful life and a projected one-of-a-kind, full-scale manufactured cost of less than $400 per kilowatt. The program adapted the existing on-site Configuration-B cell design to electric utility operating conditions and introduced additional new design features. Task 1 consisted of the conceptual design of a full-scale electric utility cell stack that meets program objectives. The conceptual design was updated to incorporate the results of material and process developments in tasks 2 and 3, as well as results of stack tests conducted in task 6. Tasks 2 and 3 developed the materials and processes required to fabricate the components that meet the program objectives. The design of the small area and 10-sq. ft. stacks was conducted in task 4. Fabrication and assembly of the short stacks were conducted in task 5 and subsequent tests were conducted in task 6. The management and reporting functions of task 7 provided DOE/METC with program visibility through required documentation and program reviews. This report describes the cell design and development effort that was conducted to demonstrate, by subscale stack test, the technical achievements made toward the above program objectives.

1992-09-01

46

Water-cooled beam line components at LAMPF  

SciTech Connect

The beam line components that comprise the main experimental beam at the Clinton P. Anderson Meson Physics Facility (LAMPF) have been operating since February 1976. This paper will define the functions of the primary water-cooled elements, their design evolution, and our operating experience to the present time.

Grisham, D.L.; Lambert, J.E.

1981-01-01

47

Computational Simulation of a Water-Cooled Heat Pump  

NASA Technical Reports Server (NTRS)

A Fortran-language computer program for simulating the operation of a water-cooled vapor-compression heat pump in any orientation with respect to gravity has been developed by modifying a prior general-purpose heat-pump design code used at Oak Ridge National Laboratory (ORNL).

Bozarth, Duane

2008-01-01

48

Water cooled anode increases life of high temperature arc lamp  

NASA Technical Reports Server (NTRS)

Water cooling system increases the life of the anode of a high temperature compact arc lamp. A shaped water passage is provided through the tip or hottest point of the anode so that water will flow through it at a relatively high velocity.

Riise, H. N.

1967-01-01

49

MATERIALS CHALLENGES FOR THE SUPERCRITICAL WATER-COOLED REACTOR (SCWR)  

Microsoft Academic Search

This paper discusses the materials requirements of the Supercritical Water-cooled Reactor (SCWR) which arise from its severe expected operating conditions: (i) Outlet Temperature (to 650 C); (ii) Pressure of 25 MPa for the coolant containment, (iii) Thermochemical stress in the presence of supercritical water, and (iv) Radiative damage (up to 150 dpa for the fast spectrum variant). These operating conditions

Satyen Baindur

50

Summary of research and development effort on air and water cooling of gas turbine blades  

SciTech Connect

The review on air- and water-cooled gas turbines from the 1904 Lemale-Armengaud water-cooled gas turbine, the 1948 to 1952 NACA work, and the program at GE indicates that the potential of air cooling has been largely exploited in reaching temperatures of 1100/sup 0/C (approx. 2000/sup 0/F) in utility service and that further increases in turbine inlet temperature may be obtained with water cooling. The local heat flux in the first-stage turbine rotor with water cooling is very high, yielding high-temperature gradients and severe thermal stresses. Analyses and tests indicate that by employing a blade with an outer cladding of an approx. 1-mm-thick oxidation-resistant high-nickel alloy, a sublayer of a high-thermal-conductivity, high-strength, copper alloy containing closely spaced cooling passages approx. 2 mm in ID to minimize thermal gradients, and a central high-strength alloy structural spar, it appears possible to operate a water-cooled gas turbine with an inlet gas temperature of 1370/sup 0/C. The cooling-water passages must be lined with an iron-chrome-nickel alloy must be bent 90/sup 0/ to extend in a neatly spaced array through the platform at the base of the blade. The complex geometry of the blade design presents truly formidable fabrication problems. The water flow rate to each of many thousands of coolant passages must be metered and held to within rather close limits because the heat flux is so high that a local flow interruption of only a few seconds would lead to a serious failure.Heat losses to the cooling water will run approx. 10% of the heat from the fuel. By recoverying this waste heat for feedwater heating in a command cycle, these heat losses will give a degradation in the power plant output of approx. 5% relative to what might be obtained if no cooling were required. However, the associated power loss is less than half that to be expected with an elegant air cooling system.

Fraas, A.P.

1980-03-01

51

Corrosion mechanisms of candidate structural materials for supercritical water-cooled reactor  

Microsoft Academic Search

Nickel-based alloys, austenitic stainless steel, ferritic\\/martensitic heat-resistant steels, and oxide dispersion strengthened\\u000a steel are presently considered to be the candidate structural or fuel-cladding materials for supercritical water-cooled reactor\\u000a (SCWR), one of the promising generation IV reactor for large-scale electric power production. However, corrosion and stress\\u000a corrosion cracking of these candidate alloys still remain to be a major problem in the

Lefu Zhang; Fawen Zhu; Rui Tang

2009-01-01

52

Deployment Scenario of Heavy Water Cooled Thorium Breeder Reactor  

SciTech Connect

Deployment scenario of heavy water cooled thorium breeder reactor has been studied. We have assumed to use plutonium and thorium oxide fuel in water cooled reactor to produce {sup 233}U which will be used in thorium breeder reactor. The objective is to analysis the potential of water cooled Th-Pu reactor for replacing all of current LWRs especially in Japan. In this paper, the standard Pressurize Water Reactor (PWR) has been designed to produce 3423 MWt; (i) Th-Pu PWR, (ii) Th-Pu HWR (MFR = 1.0) and (iii) Th-Pu HWR (MFR 1.2). The properties and performance of the core were investigated by using cell and core calculation code. Th-Pu PWR or HWR produces {sup 233}U to introduce thorium breeder reactor. The result showed that to replace all (60 GWe) LWR by thorium breeder reactor within a period of one century, Th-Pu oxide fueled PWR has insufficient capability to produce necessary amount of {sup 233}U and Th-Pu oxide fueled HWR has almost enough potential to produce {sup 233}U but shows positive void reactivity coefficient.

Mardiansah, Deby; Takaki, Naoyuki [Course of Applied Science, School of Engineering, Tokai University (Japan)

2010-06-22

53

THE EFFECTS OF BERYLLIA REFLECTOR ELEMENTS ON A HIGHLY ENRICHED LIGHT-WATER MODERATED REACTOR  

Microsoft Academic Search

The performance and use of beryllium oxide reflector elements are ; described wlth respect to improvements made in a water moderated reactor ; utilizing the elements. Since beryllia does not absorb neutrons as markedly as ; water it may be used for filling the vacant spaces in the lattice plates, thereby ; giving the neutron currents more facility. Since beryllia

P. N. Cooper; W. M. Cooper; K. Firth; A. J. Salmon

1962-01-01

54

Improved water-cooled cyclone constructions in CFBs  

SciTech Connect

The construction of CFB boilers has advanced in comparison with early designs. One improvement has been the use of water or steam cooled cyclones, which allows the use of thin refractories and minimizes maintenance needs. Cooled cyclones are also tolerant of wide load variations when the main fuel is biologically based, and coal or some other fuel is used as a back-up. With uncooled cyclones, load changes with high volatile fuels can mean significant temperature transients in the refractory, due to post-combustion phenomena in the cyclone. Kvaerner's development of water-cooled cyclones for CFBs began in the early 1980s. The first boiler with this design was delivered in 1985 in Sweden. Since then, Kvaerner Pulping has delivered over twenty units with cooled cyclones, in capacity ranging from small units up to 400 MW{sub th}. Among these units, Kvaerner has developed unconventional solutions for CFBs, in order to simplify the constructions and to increase the reliability for different applications. The first of them was CYMIC{reg{underscore}sign}, which has its water-cooled cyclone built inside the boiler furnace. There are two commercial CYMIC boilers in operation and one in project stages. The largest CYMIC in operation is a 185 MW{sub th} industrial boiler burning various fuels. For even larger scale units Kvaerner developed the Integrated Cylindrical Cyclone and Loopseal (ICCL) assembly. One of these installations is in operation in USA, having steaming capacity of over 500 t/h. The design bases of these new solutions are quite different in comparison with conventional cyclones. Therefore, an important part of the development has been cold model testing and mathematical modeling of the cyclones. This paper reviews the state-of-the-art in water-cooled cyclone construction. The new solutions, their full-scale experience, and a comparison of the actual experience with the preliminary modeling work are introduced.

Alliston, M.G.; Luomaharju, T.; Kokko, A.

1999-07-01

55

Pink-Beam, Highly-Accurate Compact Water Cooled Slits  

NASA Astrophysics Data System (ADS)

Advanced Design Consulting, Inc. (ADC) has designed accurate compact slits for applications where high precision is required. The system consists of vertical and horizontal slit mechanisms, a vacuum vessel which houses them, water cooling lines with vacuum guards connected to the individual blades, stepper motors with linear encoders, limit (home position) switches and electrical connections including internal wiring for a drain current measurement system. The total slit size is adjustable from 0 to 15 mm both vertically and horizontally. Each of the four blades are individually controlled and motorized. In this paper, a summary of the design and Finite Element Analysis of the system are presented.

Lyndaker, Aaron; Deyhim, Alex; Jayne, Richard; Waterman, Dave; Caletka, Dave; Steadman, Paul; Dhesi, Sarnjeet

2007-01-01

56

Numerical analysis of thermal effects in semiconductor disk laser with water cooling  

NASA Astrophysics Data System (ADS)

This paper has established a thermal model of Vertical-external-cavity surface-emitting semiconductor laser (VECSELs) with water-cooled heatsink, calculated the distribution of temperature field with finite element method, and studied the effects of pumping light, heat transfer coefficient, and heatsink characteristics on the maximum temperature of the quantum well. Calculations show that there is an optimal heat transfer coefficient value interval, thermal conductivity of the VECSELs heatsink will have a significant impact on the maximum temperature of the quantum well, and increasing area of cooler heatsink would help to improve heat dissipation performance. It also shows that the maximum temperature of the quantum well has a linear relationship with pump power, and a nearly inverse relationship with the spot size. Due to thermal diffusion of water-cooled heatsink for VECSELs point heat source, the maximum temperature of quantum well is not sensitive to thickness and area of the heatsink, heat dissipation performance which uses a diamond heatsink is about 1.7 times the oxygen-free copper heatsink.

Zhu, Renjiang; Pan, Yingjun; Jiang, Maohua; Zhang, Peng

2014-11-01

57

Water cooled metal optics for the Advanced Light Source  

SciTech Connect

The program for providing water cooled metal optics for the Advanced Light Source at Berkeley is reviewed with respect to fabrication and metrology of the surfaces. Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from prototype mirrors and grating blanks will be presented, which show exceptionally low microroughness and mid-period error. We will briefly describe out improved version of the Long Trace Profiler, and its importance to out metrology program. We have completely redesigned the mechanical, optical and computational parts of the profiler system with the cooperation of Peter Takacs of Brookhaven, Continental Optical, and Baker Manufacturing. Most important is that one of our profilers is in use at the vendor to allow testing during fabrication. Metrology from the first water cooled mirror for an ALS beamline is presented as an example. The preplating processing and grinding and polishing were done by Tucson Optical. We will show significantly better surface microroughness on electroless nickel, over large areas, than has been reported previously.

McKinney, W.R.; Irick, S.C. [Lawrence Berkeley Lab., CA (United States); Lunt, D.L.J. [Tucson Optical Research Corp., AZ (United States)

1991-10-28

58

Research of a Supercritical Pressure Water Cooled Reactor in Korea  

SciTech Connect

In this paper the activities on the supercritical pressure water-cooled reactor (SCWR) in Korea are briefly introduced. Four projects on a SCWR are being conducted in Korea. Three of them are supported by the I-NERI program while one is by KAERI. Two of the I-NERI-supported projects concern suitable materials for supercritical pressure and temperature, and radiation environment. The other I-NERI-supported project surveys numerically and experimentally the proper turbulence modeling for the numerical calculation of heat transfer phenomena at a supercritical condition. Heat transfer at a supercritical condition is being studied at KAERI experimentally using carbon dioxide as a coolant. The test loop is to be completed by the end of 2004. (authors)

Bae, Yoon-Yeong; Joo, Hyung-Kook; Jang, Jinsung; Jeong, Yong-Hwan; Song, Jin-ho; Yoon, Han-Young [Korea Atomic Energy Research Institute, 150 Deokjin, Yuseong, Daejeon 305-353 (Korea, Republic of); Yoo, Jung-Yul [School of Mechanical and Aerospace Engineering, Seoul National University, San 56-1 Shinlim-dong, Kwanak-gu, Seoul 151-742 (Korea, Republic of)

2004-07-01

59

A dynamic mathematical model of a direct expansion (DX) water-cooled air-conditioning plant  

Microsoft Academic Search

A dynamic mathematical model for a direct expansion water-cooled air-conditioning plant typical to many actual installations in buildings has been developed. The system components modelled are a compressor, a thermostatic expansion valve, a water cooled condenser and a direct expansion evaporator which is also the cooling and dehumidifying coil in the air side. The evaporator (cooling coil) model consists of

Deng Shiming

2000-01-01

60

Study of a water-cooled fluidized bed for diesel particle agglomeration  

Microsoft Academic Search

A water-cooled fluidized bed particle trap has been built and tested for diesel particle agglomeration. A theoretical formula incorporating thermophoretic mechanisms into normal fluidized bed filtration has been derived to calculate particle removal efficiency in a water-cooled fluidized bed and validated with published data and measurements from this study. Reasonably good agreement between the measurements and model predictions is achieved.

Ji Ping Shi; Roy M. Harrison

2001-01-01

61

Neutronic potential of water cooled reactor with actinide closed fuel cycle  

Microsoft Academic Search

Neutronic potential of water-cooled reactor on the efficient use of Uranium by multiple recycling of all actinides have been examined after a brief-review of alternative coolants to sodium which are applicable for fast neutron reactors. The water-cooled reactor which was designed to have tight lattice and lower Hydrogen\\/Heavy-Metal number density ratio (H\\/HM

Naoyuki Takaki

2000-01-01

62

TRITIUM ANALYSIS OF A WATER-COOLED SOLID BREEDER BLANKET FOR ITER*  

E-print Network

TRITIUM ANALYSIS OF A WATER-COOLED SOLID BREEDER BLANKET FOR ITER* G. Federici, A.R. Raffray, M: This paper presents quantitativepredict,ionsfor the tritium release and inventory in a water-cooled solid microstructure, the purge ga. compositionand the operating burn and dwell times. INTRODUCTION A water

Abdou, Mohamed

63

Nitrogen-16 Generation and Transport and Associated Shielding Requirements in a Supercritical-Water-Cooled Reactor  

SciTech Connect

As a water-cooled nuclear system with a direct thermal cycle, the supercritical-water-cooled reactor (SCWR) shares with the boiling water reactor (BWR) the issue of coolant activation and transport of the coolant activation products to the turbine and balance of plant (BOP). Consistent with the BWR experience, the dominant nuclide contributing to the SCWR coolant radioactivity at full power is {sup 16}N, which is produced by an (n,p) reaction on {sup 16}O. In this paper the production and decay of {sup 16}N in the SCWR coolant circuit along with the shielding requirements imposed on the BOP are analyzed and compared with those in a BWR with a similar thermal power rating. A simple control-mass approach is adopted in which the {sup 16}N inventory in a unit mass of coolant is tracked as the coolant flows in the SCWR and BWR primary systems, which are divided into several compartments (e.g., core, lower plenum, downcomer, etc.) of known volume, mass flow rate, and neutron flux. The values of the neutron flux and (n,p) cross section in the SCWR and BWR cores are calculated by means of full-length radially reflected Monte Carlo eigenvalue models of the SCWR and BWR fuel assemblies. The results are as follows: The {sup 16}N activities in the steam lines of the BWR with normal water chemistry, in the BWR with hydrogen water chemistry, and in the SCWR are about 40, 180, and 380 {mu}Ci/g, respectively. The calculated BWR values compare well with the trends and ranges found in the literature. The SCWR {sup 16}N concentration is significantly higher than that in the BWR for the following four reasons:1. The coolant transit time in the SCWR core is about twice that in the BWR core.2. The neutron flux is higher in the SCWR because of the higher power density.3. The slow coolant pass in the water rods produces a significant {sup 16}N activity at the SCWR core inlet.4. In the SCWR all the {sup 16}N generated in the core is sent to the steam lines because there is no recirculation within the vessel.A simple gamma attenuation model shows that the higher {sup 16}N activity in the SCWR results in shielding requirements only up to 10% higher than for the BWR with hydrogen water chemistry. However, because of the higher SCWR electric power, the specific shielding costs per unit of electric power associated with {sup 16}N are expected to be similar to or better than that for BWRs.

Fischer, Benjamin [University of Wisconsin at Madison (United States); Smolinski, Marci [University of Wisconsin at Madison (United States); Buongiorno, Jacopo [Idaho National Engineering and Environmental Laboratory (United States)

2004-08-15

64

Nitrogen-16 Generation, Transport and Associated Shielding Requirements in the Supercritical-Water-Cooled Reactor  

SciTech Connect

As a water-cooled nuclear system with a direct thermal cycle, the supercritical-water-cooled reactor (SCWR) shares with the boiling water reactor (BWR) the issue of coolant activation and transport of the coolant activation products to the turbine and balance of plant (BOP). Consistent with the BWR experience, the dominant nuclide contributing to the SCWR coolant radioactivity at full power is 16N, which is produced by an (n,p) reaction on 16O. In this paper the production and decay of 16N in the SCWR coolant circuit along with the shielding requirements imposed on the BOP are analyzed and compared with those in a BWR with a similar thermal power rating. A simple control-mass approach is adopted in which the 16N inventory in a unit mass of coolant is tracked as the coolant flows in the SCWR and BWR primary systems, which are divided into several compartments (e.g., core, lower plenum, downcomer, etc.) of known volume, mass flow rate, and neutron flux. The values of the neutron flux and (n,p) cross section in the SCWR and BWR cores are calculated by means of full-length radially reflected Monte Carlo eigenvalue models of the SCWR and BWR fuel assemblies. The results are as follows: The 16N activities in the steam lines of the BWR with normal water chemistry, in the BWR with hydrogen water chemistry, and in the SCWR are about 40, 180, and 380 Ci/g, respectively. The calculated BWR values compare well with the trends and ranges found in the literature. The SCWR 16N concentration is significantly higher than that in the BWR for the following four reasons: 1. The coolant transit time in the SCWR core is about twice that in the BWR core. 2. The neutron flux is higher in the SCWR because of the higher power density. 3. The slow coolant pass in the water rods produces a significant 16N activity at the SCWR core inlet. 4. In the SCWR all the 16N generated in the core is sent to the steam lines because there is no recirculation within the vessel. A simple gamma attenuation model shows that the higher 16N activity in the SCWR results in shielding requirements only up to 10% higher than for the BWR with hydrogen water chemistry. However, because of the higher SCWR electric power, the specific shielding costs per unit of electric power associated with 16N are expected to be similar to or better than that for BWRs.

Jacopo Buongiorno

2004-08-01

65

Passive cooling means for water cooled nuclear reactor plants  

SciTech Connect

This patent describes a water cooled, nuclear fission reactor plant having an improved auxiliary passive cooling system for dissipating heat produced during periods of other than normal operation, the nuclear fission reactor plant. It comprises the combination of: a reactor pressure vessel containing a core of heat producing fissionable fuel material provided with reciprocally removable fission control rods and having external steam and hot coolant water conduits extending out therefrom including a circulation loop passing through a heat exchanger comprising a steam driven turbine, the reactor pressure vessel and adjacent components being housed within an enclosing, substantially gas impermeable containment structure for retaining a gaseous atmosphere enveloping the reactor pressure vessel and adjacent components; a container retaining a pool of cooling water isolated from the atmosphere of the containment structure and positioned at a level within the containment structure above the reactor pressure vessel, the isolation container including a heat exchanger unit submerged in the retained pool of cooling water having an inlet which is in optional fluid communication with the interior of the reactor pressure vessel and with the atmosphere of the containment structure enveloping the pressure vessel; a suppression pool chamber containing a pool of cooling water for condensing steam positioned adjacent to the reactor pressure vessel and having a horizontal vent passing to an adjoining area which is in open communication to the atmosphere of the containment structure; a vent duct extending from an outlet of the heat exchanger unit submerged in the isolation container pool downward into the suppression pool chamber with its open end terminating below the surface of the cooling water pool and above the level of the horizontal vent passing an adjoining area.

Gluntz, D.M.; Oosterkamp, W.J.; van Kuijk, R.M.

1992-04-07

66

An economic analysis of a light and heavy water moderated reactor synergy: burning americium using recycled uranium  

SciTech Connect

An economic analysis is presented for a proposed synergistic system between 2 nuclear utilities, one operating light water reactors (LWR) and another running a fleet of heavy water moderated reactors (HWR). Americium is partitioned from LWR spent nuclear fuel (SNF) to be transmuted in HWRs, with a consequent averted disposal cost to the LWR operator. In return, reprocessed uranium (RU) is supplied to the HWRs in sufficient quantities to support their operation both as power generators and americium burners. Two simplifying assumptions have been made. First, the economic value of RU is a linear function of the cost of fresh natural uranium (NU), and secondly, plutonium recycling for a third utility running a mixed oxide (MOX) fuelled reactor fleet has been already taking place, so that the extra cost of americium recycling is manageable. We conclude that, in order for this scenario to be economically attractive to the LWR operator, the averted disposal cost due to partitioning americium from LWR spent fuel must exceed 214 dollars per kg, comparable to estimates of the permanent disposal cost of the high level waste (HLW) from reprocessing spent LWR fuel. (authors)

Wojtaszek, D.; Edwards, G. [Atomic Energy of Canada Ltd., Chalk River Laboratories, Chalk River, Ontario (Canada)

2013-07-01

67

Standard Guide for In-Service Annealing of Light-Water Moderated Nuclear Reactor Vessels  

E-print Network

1.1 This guide covers the general procedures to be considered for conducting an in-service thermal anneal of a light-water moderated nuclear reactor vessel and demonstrating the effectiveness of the procedure. The purpose of this in-service annealing (heat treatment) is to improve the mechanical properties, especially fracture toughness, of the reactor vessel materials previously degraded by neutron embrittlement. The improvement in mechanical properties generally is assessed using Charpy V-notch impact test results, or alternatively, fracture toughness test results or inferred toughness property changes from tensile, hardness, indentation, or other miniature specimen testing (1). 1.2 This guide is designed to accommodate the variable response of reactor-vessel materials in post-irradiation annealing at various temperatures and different time periods. Certain inherent limiting factors must be considered in developing an annealing procedure. These factors include system-design limitations; physical constrain...

American Society for Testing and Materials. Philadelphia

2003-01-01

68

Summary of experimental data for critical arrays of water moderated Fast Test Reactor fuel  

SciTech Connect

A research program, funded by the Consolidated Fuel Reprocessing Program (CFRP) of Oak Ridge National Laboratory (ORNL), was initiated at Battelle Pacific Northwest Laboratory (PNL) to acquire experimental data on heterogeneous water moderated arrays of Fast Test Reactor (FTR) fuel pins. The objective of this program is to provide critical experiment data for validating calculational techniques used in criticality assessments of reprocessing equipment containing FTR-type fuels. Consequently, the experiments were designed to permit accurate definition in Monte Carlo computer codes currently used in these assessments. Square and triangular pitched lattices of fuel have been constructed under a variety of conditions covering the range from undermoderated to overmoderated arrays. Experiments were conducted composed of arrays which were water reflected, partially concrete reflected, and arrays with interspersed solid neutron absorbers. The absorbers utilized were Boral, and cadmium plates and gadolinium cylindrical rods. Data from non-CFRP sponsored subcritical experiments (previously performed at Hanford) also are included.

Durst, B.M.; Bierman, S.R.; Clayton, E.D.; Mincey, J.F.; Primm, R.T. III

1981-05-01

69

Applying a Domestic Water-cooled Air-conditioner in Subtropical Cities  

E-print Network

Water-cooled air-conditioning systems (WACS) are in general more energy efficient than air-cooled air-conditioning systems (AACS), especially in subtropical climates where the outdoor air is hot and humid. Related studies focused on evaluating...

Lee, W.; Chen, H.

2006-01-01

70

A study on the energy performance of three schemes for widening application of water-cooled air-conditioning systems in Hong Kong  

Microsoft Academic Search

The Hong Kong Government intends to reduce greenhouse gases emissions from power stations through widening application of the more energy efficient water-cooled air-conditioning systems (WACS) in buildings. Consideration is being given to the development of centralized, district wide systems for supplying seawater for once-through condenser cooling (the CPSSCC scheme), or for make-up of water losses at cooling towers (the CPSSCT

F. W. H. Yik; J. Burnett; I. Prescott

2001-01-01

71

Modified conversion ratio measurement in light water-moderated UO{sub 2} lattices  

SciTech Connect

To investigate the accuracy of the neutronic calculations in various neutron spectra, the modified conversion ratios [(MCR): ratio of {sup 238}U capture rate-to-total fission rate] of four kinds of light water-moderated UO{sub 2} fuel lattices were measured. In the measurements, the relative reaction rates of {sup 238}U capture and total fission were obtained from the nondestructive gamma-ray spectrometry of {sup 239}Np and {sup 143}Ce, respectively, which accumulated in the fuel rod irradiated at the Tank-Type Critical Assembly. The moderator-to-fuel volume ratios V{sub m}/V{sub f} of the measured lattices were 1.50 (undermoderate) to 3.00 (overmoderate). The measured MCRs were 0.477 {+-} 0.014(V{sub m}/V{sub f} = 1.50), 0.434 {+-} 0.013(1.83), 0.383 {+-} 0.011(2.48), and 0.356 {+-} 0.011(3.00), respectively. The Monte Carlo calculation employing the JENDL-3 library showed good agreement with the experiments for all the cores, although they showed a tendency of overestimation for larger values of MCR, as shown in the case of UO{sub 2} tight lattices. Therefore, it was concluded that, for the cores investigated, the accuracy of the neutronic calculation method currently used was very good.

Nakajima, Ken; Akai, Masanori [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Dept. of Fuel Cycle Safety Research

1996-03-01

72

Thermal Aspects of Using Alternative Nuclear Fuels in Supercritical Water-Cooled Reactors  

NASA Astrophysics Data System (ADS)

A SuperCritical Water-cooled Nuclear Reactor (SCWR) is a Generation IV concept currently being developed worldwide. Unique to this reactor type is the use of light-water coolant above its critical point. The current research presents a thermal-hydraulic analysis of a single fuel channel within a Pressure Tube (PT)-type SCWR with a single-reheat cycle. Since this reactor is in its early design phase many fuel-channel components are being investigated in various combinations. Analysis inputs are: steam cycle, Axial Heat Flux Profile (AHFP), fuel-bundle geometry, and thermophysical properties of reactor coolant, fuel sheath and fuel. Uniform and non-uniform AHFPs for average channel power were applied to a variety of alternative fuels (mixed oxide, thorium dioxide, uranium dicarbide, uranium nitride and uranium carbide) enclosed in an Inconel-600 43-element bundle. The results depict bulk-fluid, outer-sheath and fuel-centreline temperature profiles together with the Heat Transfer Coefficient (HTC) profiles along the heated length of fuel channel. The objective is to identify the best options in terms of fuel, sheath material and AHFPS in which the outer-sheath and fuel-centreline temperatures will be below the accepted temperature limits of 850C and 1850C respectively. The 43-element Inconel-600 fuel bundle is suitable for SCWR use as the sheath-temperature design limit of 850C was maintained for all analyzed cases at average channel power. Thoria, UC2, UN and UC fuels for all AHFPs are acceptable since the maximum fuel-centreline temperature does not exceed the industry accepted limit of 1850C. Conversely, the fuel-centreline temperature limit was exceeded for MOX at all AHFPs, and UO2 for both cosine and downstream-skewed cosine AHFPs. Therefore, fuel-bundle modifications are required for UO2 and MOX to be feasible nuclear fuels for SCWRs.

Grande, Lisa Christine

73

Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors  

SciTech Connect

The irradiation of Th{sup 232} breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U{sup 238}. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in the Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction ?) for coolant voiding as standard NU fuel. (authors)

Bhatti, Zaki; Hyland, B.; Edwards, G.W.R. [Atomic Energy of Canada Limited, Chalk River Laboratories, 1 Plant Road, Chalk River, Ontario, K0J 1J0 (Canada)

2013-07-01

74

A water-cooled mirror system for synchrotron radiation  

SciTech Connect

This paper describes the design and performance of a directly-cooled soft x-ray mirror system which has been developed at Lawrence Berkeley Laboratory for synchrotron radiation beam lines in which mirror thermal distortion must be minimized for acceptable optical performance. Two similar mirror systems are being built: the first mirror has been installed and operated at the National Synchrotron Light Source on the X-17T mini-undulator beam line and will be moved to the permanent X-1 beam line when a new, more powerful undulator is installed there. The second system is being built for installation at the Stanford Synchrotron Radiation Laboratory on Beam Line VI, where the total absorbed power on the mirror may be as high as 2400 W with peak absorbed power density of 520 W/cm/sup 2/. Direct cooling by convection is achieved using internal water channels in a brazed, dispersion-strengthened copper and OFHC copper substrate with a polished electroless-nickel surface. A simple kinematic linkage and flexural pivot mounting provide for mirror positioning about two rotational axes that coincide with the optical surface. Surface figure metrology, optical configurations, and tolerancing are also discussed. 11 refs., 8 figs.

DiGennaro, R.; Gee, B.; Guigli, J.; Hogrefe, H.; Howells, M.; Rarback, H.

1987-06-01

75

Supercritical-pressure, Once-through Cycle Light Water Cooled Reactor Concept  

Microsoft Academic Search

The purpose of the study is to develop new reactor concepts for the innovation of light water reactors (LWR) and fast reactors. Concept of the once-through coolant cycle, supercritical-pressure light water cooled reactor was developed. Major aspects of reactor design and safety were analysed by the computer codes which were developed by ourselves. It includes core design of thermal and

Yoshiaki OKA; Seiichi KOSHIZUKA

2001-01-01

76

A numerical analysis of heat and mass transfer inside a reversibly used water cooling tower  

Microsoft Academic Search

In subtropical regions, a desuperheater heat recovery system for service hot-water heating can be applied. However, in colder seasons when building cooling load is reduced, a standard water-cooling tower may be reversibly used to extract free heat from ambient air to make up the reduction of heat source for water heating. Previous related work included developing an analytical method for

Kunxiong Tan; Shiming Deng

2003-01-01

77

Suboptimal onoff switching control strategies for chilled water cooling systems with storage  

Microsoft Academic Search

A dynamic model of vapour compression refrigeration system is developed. The overall model consists of the following basic components: a compressor, a condenser, an expansion valve, an evaporator, an evaporative cooler and a cool storage. The integrated system is referred to as chilled water cooling system with storage (CWCS). The mathematical modelling of the CWC system undertaken in this study

Wei-Ling Jian; M. Zaheeruddin

1998-01-01

78

Electromagnetic and thermal models of a water-cooled dipole radiating in a biological tissue  

Microsoft Academic Search

An insulated, water-cooled dipole, radiating in a biological tissue, is analyzed with a theoretical electromagnetic and thermal model. The SAR (specific absorption rate) and temperature distributions are calculated taking into account the effect of the water flowing inside the applicator. The steady-state temperatures in a dissipative medium, interacting with the dipole, are evaluated for several thicknesses of the external casing,

Guido Biffi Gentili; M. Leoncini; F. Gori

1991-01-01

79

Tritium analysis of a water-cooled solid breeder blanket for ITER  

Microsoft Academic Search

Quantitative predictions are presented for the tritium release and inventory in a water-cooled solid breeder blanket for the International Thermonuclear Experimental Reactor (ITER). The predictions were obtained from the tritium transport code MISTRAL, recently developed at UCLA. The blanket consists of a layout assembly of solid breeder and beryllium multiplier, with two layers of solid breeder in the outboard region

G. Federici; A. R. Raffray; M. A. Abdou

1989-01-01

80

Recent progress in safety assessments of Japanese water-cooled solid breeder test blanket module  

Microsoft Academic Search

This paper presents summary of preliminary safety assessment of the water-cooled solid breeder (WCSB) test blanket module (TBM) proposed by Japan for the ITER TBM test program. For the purpose of basic evaluation of source terms on nuclear heating and radioactivity generation, distribution of neutron flux, tritium breeding ratio, nuclear heating, decay heat and induced activity of radioactive waste are

Daigo Tsuru; Mikio Enoeda; Masato Akiba

2008-01-01

81

Understanding the Role Water-cooling Plays during Continuous Casting of Steel and Aluminum Alloys  

E-print Network

Understanding the Role Water-cooling Plays during Continuous Casting of Steel and Aluminum Alloys J Keywords: Steel, continuous casting, aluminum, Direct Chill casting, primary cooling, water the mold and solidifying metal during the continuous casting of steel and aluminum alloys

Thomas, Brian G.

82

Fuel Breeding and Core Behavior Analyses on In Core Fuel Management of Water Cooled Thorium Reactors  

Microsoft Academic Search

Thorium fuel cycle with recycled U-233 has been widely recognized having some contributions to improve the water-cooled breeder reactor program which has been shown by a feasible area of breeding and negative void reactivity which confirms that fissile of 233U contributes to better fuel breeding and effective for obtaining negative void reactivity coefficient as the main fissile material. The present

Sidik Permana; Hiroshi Sekimoto; Abdul Waris; Muhamad Nurul Subhki; Ismail

2010-01-01

83

A Qualitative Assessment of Thorium-Based Fuels in Supercritical Pressure Water Cooled Reactors  

Microsoft Academic Search

The requirements for the next generation of reactors include better economics and safety, waste minimization (particularly of the long-lived isotopes), and better proliferation resistance (both intrinsic and extrinsic). A supercritical pressure water cooled reactor has been chosen as one of the lead contenders as a Generation IV reactor due to the high thermal efficiency and compact\\/simplified plant design. In addition,

Kevan Dean Weaver; Philip Elsworth Mac Donald

2002-01-01

84

Evaluation of water cooled supersonic temperature and pressure probes for application to 1366 K flows  

NASA Technical Reports Server (NTRS)

Water cooled supersonic probes are developed to investigate total pressure, static pressure, and total temperature in high-temperature jet plumes and thereby determine the mean flow properties. Two probe concepts, designed for operation at up to 1366 K in a Mach 2 flow, are tested on a water cooled nozzle. The two probe designs - the unsymmetric four-tube cooling configuration and the symmetric annular cooling design - take measurements at 755, 1089, and 1366 K of the three parameters. The cooled total and static pressure readings are found to agree with previous test results with uncooled configurations. The total-temperature probe, however, is affected by the introduction of water coolant, and effect which is explained by the increased heat transfer across the thermocouple-bead surface. Further investigation of the effect of coolant on the temperature probe is proposed to mitigate the effect and calculate more accurate temperatures in jet plumes.

Lagen, Nicholas; Seiner, John M.

1990-01-01

85

Study of physics parameters in several water-moderated lattices of slightly enriched and natural uranium (LWBR Development Program)  

Microsoft Academic Search

The full-range Monte Carlo program RECAP was used in a consistent analysis of parameters measured in seven water-moderated uranium lattices: four were TRX lattices of slightly-enriched rods, and three were natural-uranium-slab lattices. The most important parameters were: epithermal-to-thermal ratios for ²³⁸U capture (rho²⁸) and for ²³⁵U fission (delta²⁵), ratio of ²³⁸U fission to ²³⁵U fission (delta²⁸), eigenvalue, integral fast\\/epithermal spectrum

J. Jr. Hardy; D. Klein; J. J. Volpe

1970-01-01

86

LD side-pumped Nd:YAG Q-switched laser without water cooling  

Microsoft Academic Search

A novel LD side-pumped Nd:YAG Q-switched solid-state laser, which made use of the special pumping strcture with conductive cooling instead of water cooling, was investigated.After selecting an appropriate length and diameter of Nd:YAG laser crystal rod and using three groups of laser diode centimeter bar which was composed by 12 laser diodes and uniformly arranged according to the angle of

Ming Ling; Guang-Yong Jin; Xue-Chun Tan; Zhi-Chao Wu; Zhu Liang

2009-01-01

87

Safety system consideration of a supercritical-water cooled fast reactor with simplified PSA  

Microsoft Academic Search

The probabilistic safety of the supercritical-water cooled fast reactor (SCFR) is evaluated with the simplified probabilistic safety assessment (PSA) methodology. SCFR has a once-through direct cycle where all feedwater flows through the core to the turbine at supercritical pressure. There are no recirculation loops in the once-through direct cycle system, which is the most important difference from the current light

J. H Lee; Y Oka; S Koshizuka

1999-01-01

88

Hydraulic activity of water-cooled slag and air-cooled slag at different temperatures  

Microsoft Academic Search

Water-cooled slag (WS) and air-cooled slag (AS) with similar chemical compositions and produced from the same blast furnace were investigated for their hydraulic activities at different temperatures. The kinetics of hydration of WSlime and ASlime pastes were investigated at room temperature, 100C, and 180C by the determination of unreacted lime and combined water. The hydration products were identified by XRD.

N. Y. Mostafa; S. A. S. El-Hemaly; E. I. Al-Wakeel; S. A. El-Korashy; P. W. Brown

2001-01-01

89

Water-cooled probe technique for the study of freeze lining formation  

Microsoft Academic Search

Furnace protection by water-cooled freeze linings becomes increasingly important as the metal producing industry attempts\\u000a to achieve higher process intensities. Systematic investigations of the growth and the resulting microstructure and compositional\\u000a profile of freeze linings are necessary to understand the behavior of freeze linings, their relation with the industrial process,\\u000a and their interaction with the wall cooling system. We have

Karel Verscheure; Mieke Campforts; Frederik Verhaeghe; Eddy Boydens; Bart Blanpain; Patrick Wollants; Maurits Van Camp

2006-01-01

90

Development of the EU water-cooled Pb17Li blanket  

Microsoft Academic Search

The reference concept of the EU water-cooled Pb-17Li DEMO blanket is essentially formed by a directly-cooled steel box having the function of Pb-17Li container and by a double-wall U-tube bundle, immersed in the liquid metal, in which the pressurised water-coolant flows. The structural material is martensitic steel. All blanket performances satisfy DEMO requirements, such as tritium breeding self-sufficiency, capability of

L. Giancarli; G. Benamati; M. Ftterer; G. Marbach; C. Nardi; J. Reimann

1998-01-01

91

Mathematical modeling of evaporative cooling of water films in water-cooling towers  

Microsoft Academic Search

A mathematical model of evaporative cooling of water films flowing down vertical guards in a chimney-type water-cooling tower\\u000a is developed. Results of a qualitative analysis of the nonlinear mathematical model are reported. Data obtained from a numerical\\u000a solution of a boundary-value problem for a system of ordinary differential equations are presented in the form of graphs.

A. I. Petruchik; S. P. Fisenko

1999-01-01

92

Solidification of aluminium alloys under ultrasonic irradiation using water-cooled resonator  

Microsoft Academic Search

The present investigation attempts to evaluate the effect of ultrasonic treatment using water-cooled resonator on the microstructure and properties of different commercial Al-based alloys. The effect of ultrasonic treatment on the as-cast alloy microstructure can be summarized as follows: reduction of mean grain size, variation of phase distribution and better material homogeneity and segregation control. Ultrasonically treated samples have elongation

V Abramov; O Abramov; V Bulgakov; F Sommer

1998-01-01

93

Development of a LOCA analysis code for the supercritical-pressure light water cooled reactors  

Microsoft Academic Search

The supercritical-pressure light water cooled reactors aim at cost reduction by system simplification and higher thermal efficiency, and have flexibility for the fuel cycle due to technical feasibility for various neutron spectrum reactors. Since loss-of-coolant accident (LOCA) behavior at supercritical pressure conditions cannot be analyzed with the existing codes for the current light water reactors, a LOCA analysis code for

Jong Ho Lee; Seiichi Koshizuka; Yoshiaki Oka

1998-01-01

94

Discrete-time VSS temperature control for a plastic extrusion process with water cooling systems  

Microsoft Academic Search

The plastic extrusion process with water cooling is a variable structure system in nature. To implement discrete-time variable structure control, three important problems are considered. They are: choice of dynamic sliding surface for a system with relative degree greater than one, computation of the discrete-time dynamic sliding surface variable (sk), and self-tuning of the switching control magnitude to reduce chatterings.

Wu-Chung Su; Ching-Chih Tsai

2001-01-01

95

Thermal-hydraulic performance of a water-cooled tungsten-rod target for a spallation neutron source  

SciTech Connect

A thermal-hydraulic (T-H) analysis is conducted to determine the feasibility and limitations of a water-cooled tungsten-rod target at powers of 1 MW and above. The target evaluated has a 10-cm x 10-cm cross section perpendicular to the beam axis, which is typical of an experimental spallation neutron source - both for a short-pulse spallation source and long-pulse spallation source. This report describes the T-H model and assumptions that are used to evaluate the target. A 1-MW baseline target is examined, and the results indicate that this target should easily handle the T-H requirements. The possibility of operating at powers >1 MW is also examined. The T-H design is limited by the condition that the coolant does not boil (actual limits are on surface subcooling and wall heat flux); material temperature limits are not approached. Three possible methods of enhancing the target power capability are presented: reducing peak power density, altering pin dimensions, and improving coolant conditions (pressure and temperature). Based on simple calculations, it appears that this target concept should have little trouble reaching the 2-MW range (from a purely T-H standpoint), and possibly much higher powers. However, one must keep in mind that these conclusions are based solely on thermal-hydraulics. It is possible, and perhaps likely, that target performance could be limited by structural issues at higher powers, particularly for a short-pulse spallation source because of thermal shock issues.

Poston, D.I.

1997-08-01

96

Annular seed-blanket thorium fuel core concepts for heavy water moderated reactors  

SciTech Connect

New reactor concepts to implement thorium-based fuel cycles have been explored to achieve maximum resource utilization. Pressure tube heavy water reactors (PT-HWR) are highly advantageous for implementing the use of thorium-based fuels because of their high neutron economy and on-line re-fuelling capability. The use of heterogeneous seed-blanket core concepts in a PT-HWR where higher-fissile-content seed fuel bundles are physically separate from lower-fissile-content blanket bundles allows more flexibility and control in fuel management to maximize the fissile utilization and conversion of fertile fuel. The lattice concept chosen is a 35-element bundle made with a homogeneous mixture of reactor grade Pu and Th, and with a central zirconia rod to help reduce coolant void reactivity. Several annular heterogeneous seed-blanket core concepts with plutonium-thorium-based fuels in a 700-MWe-class PT-HWR were analyzed, using a once-through thorium (OTT) cycle. Different combinations of seed and blanket fuel were tested to determine the impact on core-average burnup, fissile utilization, power distributions, and other performance parameters. It was found that the various core concepts can achieve a fissile utilization that is up to 30% higher than is currently achieved in a PT-HWR using conventional natural uranium fuel bundles. Up to 67% of the Pu is consumed; up to 43% of the energy is produced from thorium, and up to 363 kg/year of U-233 is produced. Seed-blanket cores with ?50% content of low-power blanket bundles may require power de-rating (?58% to 65%) to avoid exceeding maximum limits for peak channel power, bundle power and linear element ratings. (authors)

Bromley, B.P.; Hyland, B. [Atomic Energy of Canada Limited, Chalk River Laboratories, 1 Plant Road, Chalk River, Ontario, K0J 1J0 (Canada)

2013-07-01

97

Modification and Validation of a Universal Thermodynamic Chiller Model Used to Evaluate the Performance of Water-Cooled Centrifugal Chillers  

E-print Network

MODIFICATION AND VALIDATION OF A UNIVERSAL THERMODYNAMIC CHILLER MODEL USED TO EVALUATE THE PERFORMANCE OF WATER-COOLED CENTRIFUGAL CHILLERS Irene E. Figueroa, M.S. Engineer Bell Helicopter-Textron Hurs t. TX Mario A. Medina, Ph.D. Asst... that are commonly found in space cooling applications: the water-cooled centrifugal chiller. The "efficiency" of,chillers is expressed in terms of the coefficient of performance (COP), which is defined as the cooling capacity of the chiller (at the evaporator...

Figueroa, I. E.; Cathey, M.; Medina, M. A.; Nutter, D. W.

1998-01-01

98

Thermal Model and Behavior of a Totally-Enclosed-Water-Cooled Squirrel-Cage Induction Machine for Traction Applications  

Microsoft Academic Search

A thermal model of a totally enclosed water-cooled induction machine is presented. The axially and radially discretized physical regions of the machine are modeled in the object-oriented language Modelica. Additionally, the water-cooling jacket is modeled. The parameters of the thermal network are derived from geometric, physical, and empirical data. The main focus of the presented highly extensible model was to

Christian Kral; Anton Haumer; Thomas Bauml

2008-01-01

99

Checkerboard seed-blanket thorium fuel core concepts for heavy water moderated reactors  

SciTech Connect

New reactor concepts to implement thorium-based fuel cycles have been explored to achieve maximum resource utilization. Pressure tube heavy water reactors (PT-HWR) are highly advantageous for implementing the use of thorium-based fuels because of their high neutron economy and on-line re-fuelling capability. The use of heterogeneous seed-blanket core concepts in a PT-HWR where higher-fissile-content seed fuel bundles are physically separate from lower-fissile-content blanket bundles allows more flexibility and control in fuel management to maximize the fissile utilization and conversion of fertile fuel. The lattice concept chosen was a 35-element bundle made with a homogeneous mixture of reactor grade Pu (about 67 wt% fissile) and Th, and with a central zirconia rod to help reduce coolant void reactivity. Several checkerboard heterogeneous seed-blanket core concepts with plutonium-thorium-based fuels in a 700-MWe-class PT-HWR were analyzed, using a once-through thorium (OTT) cycle. Different combinations of seed and blanket fuel were tested to determine the impact on core-average burnup, fissile utilization, power distributions, and other performance parameters. It was found that various checkerboard core concepts can achieve a fissile utilization that is up to 26% higher than that achieved in a PT-HWR using more conventional natural uranium fuel bundles. Up to 60% of the Pu is consumed; up to 43% of the energy is produced from thorium, and up to 303 kg/year of Pa-233/U-233/U-235 are produced. Checkerboard cores with about 50% of low-power blanket bundles may require power de-rating (65% to 74%) to avoid exceeding maximum limits for channel and bundle powers and linear element ratings. (authors)

Bromley, B.P.; Hyland, B. [Atomic Energy of Canada Limited, Chalk River Laboratories, 1 Plant Road, Chalk River, Ontario, K0J 1J0 (Canada)

2013-07-01

100

Lattice cell and full core physics of internally cooled annular fuel in heavy water moderated reactors  

SciTech Connect

A program is underway at Atomic Energy of Canada Limited (AECL) to develop a new fuel bundle concept to enable greater burnups for PT-HWR (pressure tube heavy water reactor) cores. One option that AECL is investigating is an internally cooled annular fuel (ICAF) element concept. ICAF contains annular cylindrical pellets with cladding on the inner and outer diameters. Coolant flows along the outside of the element and through the centre. With such a concept, the maximum fuel temperature as a function of linear element rating is significantly reduced compared to conventional, solid-rod type fuel. The preliminary ICAF bundle concept considered in this study contains 24 half-metre long internally cooled annular fuel elements and one non-fuelled centre pin. The introduction of the non-fuelled centre pin reduces the coolant void reactivity (CVR), which is the increase in reactivity that occurs on voiding the coolant in accident scenarios. Lattice cell and full core physics calculations of the preliminary ICAF fuel bundle concept have been performed for medium burnups of approximately 18 GWd/tU using WIMS-AECL and reactor fuel simulation program (RFSP). The results will be used to assist in concept configuration optimization. The effects of radial and axial core power distributions, linear element power ratings, refuelling rates and operational power ramps have been analyzed. The results suggest that burnups of greater than 18 GWd/tU can be achieved in current reactor designs. At approximately 18 GWd/tU, expected maximum linear element ratings in a PT-HWR with online-refuelling are approximately 90 kW/m. These conditions would be prohibitive for solid-rod fuel, but may be possible in ICAF fuel given the reduced maximum fuel temperature as a function of linear element rating. (authors)

Armstrong, J.; Hamilton, H.; Hyland, B. [Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario, K0J 1J0 (Canada)

2013-07-01

101

Determination of the modified conversion ratio of light-water-moderated uranium-plutonium mixed-oxide-fuel lattice  

SciTech Connect

The modified conversion ratio (MCR) (the ratio of the {sup 238}U capture rate to the total fission rate) in a light-water-moderated uranium-plutonium mixed-oxide (MOX-) fuel lattice was measured for four types of lattices with different plutonium enrichment. In the current method, the relative reaction rates of {sup 238}U capture and total fission were obtained from nondestructive gamma-ray spectrometry of {sup 239}Np and fission products, respectively, which accumulated in the fuel rod irradiated at the Tank-Type Critical Assembly. The measured results of the fission rates derived from two different fission products agreed well with each other, and the measured MCRs showed good agreement with the results of the Monte Carlo calculation with the whole-core model. Therefore, the current nondestructive method is applicable to the MCR measurement of MOX fuel.

Nakajima, K.; Akai, Masanori; Suzaki, Takenori [Japan Atomic Energy Research Inst., Ibaraki (Japan). Dept. of Fuel Cycle Safety Research

1995-03-01

102

Soy-Based, Water-Cooled, TC W-III Two Cycle Engine Oil  

SciTech Connect

The objective of this project was to achieve technical approval and commercial launch for a biodegradable soy oil-based, environmentally safe, TC W-III performance, water-cooled, two cycle engine oil. To do so would: (1) develop a new use for RBD soybean oil; (2) increase soybean utilization in North America in the range of 500 K-3.0 MM bushels; and (3) open up supply opportunities of 1.5-5.0 MM bushels worldwide. These goals have been successfully obtained.

Scharf, Curtis R.; Miller, Mark E.

2003-08-30

103

RELAP5-3D Code for Supercritical-Pressure Light-Water-Cooled Reactors  

SciTech Connect

The RELAP5-3D computer program has been improved for analysis of supercritical-pressure, light-water-cooled reactors. Several code modifications were implemented to correct code execution failures. Changes were made to the steam table generation, steam table interpolation, metastable states, interfacial heat transfer coefficients, and transport properties (viscosity and thermal conductivity). The code modifications now allow the code to run slow transients above the critical pressure as well as blowdown transients (modified Edwards pipe and modified existing pressurized water reactor model) that pass near the critical point.

Riemke, Richard Allan; Davis, Cliff Bybee; Schultz, Richard Raphael

2003-04-01

104

Osteoid Osteoma: CT-Guided Radiofrequency Ablation Using a Water-Cooled Probe  

Microsoft Academic Search

BackgroundThe purpose of this study was to assess the safety and efficacy of computed tomography (CT) guided percutaneous radiofrequency\\u000a (RF) ablation of osteoid osteoma by using the water-cooled probe.\\u000a \\u000a \\u000a \\u000a MethodsDuring the period from July 2002 to February 2006, fifty-one patients with osteoid osteomas localized in femur (29), tibia\\u000a (10), calcaneus (2), talus (2), metatarsus (2), humerus (1), sacrum (1), scapula

A. Peyser; Y. Applbaum; A. Khoury; M. Liebergall; K. Atesok

2007-01-01

105

Fuel Breeding and Core Behavior Analyses on In Core Fuel Management of Water Cooled Thorium Reactors  

NASA Astrophysics Data System (ADS)

Thorium fuel cycle with recycled U-233 has been widely recognized having some contributions to improve the water-cooled breeder reactor program which has been shown by a feasible area of breeding and negative void reactivity which confirms that fissile of 233U contributes to better fuel breeding and effective for obtaining negative void reactivity coefficient as the main fissile material. The present study has the objective to estimate the effect of whole core configuration as well as burnup effects to the reactor core profile by adopting two dimensional model of fuel core management. About more than 40 months of cycle period has been employed for one cycle fuel irradiation of three batches fuel system for large water cooled thorium reactors. All position of fuel arrangement contributes to the total core conversion ratio which gives conversion ratio less than unity of at the BOC and it contributes to higher than unity (1.01) at the EOC after some irradiation process. Inner part and central part give the important part of breeding contribution with increasing burnup process, while criticality is reduced with increasing the irradiation time. Feasibility of breeding capability of water-cooled thorium reactors for whole core fuel arrangement has confirmed from the obtained conversion ratio which shows higher than unity. Whole core analysis on evaluating reactivity change which is caused by the change of voided condition has been employed for conservative assumption that 100% coolant and moderator are voided. It obtained always a negative void reactivity coefficient during reactor operation which shows relatively more negative void coefficient at BOC (fresh fuel composition), and it becomes less negative void coefficient with increasing the operation time. Negative value of void reactivity coefficient shows the reactor has good safety properties in relation to the reactivity profile which is the main parameter in term of criticality safety analysis. Therefore, this evaluation has confirmed that breeding condition and negative coefficient can be obtained simultaneously for water-cooled thorium reactor obtains based on the whole core fuel arrangement.

Permana, Sidik; Sekimoto, Hiroshi; Waris, Abdul; Subhki, Muhamad Nurul; Ismail

2010-12-01

106

Preparation of semi-solid aluminum alloy slurry poured through a water-cooled serpentine channel  

NASA Astrophysics Data System (ADS)

A water-cooled serpentine channel pouring process was invented to produce semi-solid A356 aluminum alloy slurry for rheocasting, and the effects of pouring temperature and circulating cooling water flux on the microstructure of the slurry were investigated. The results show that at the pouring temperature of 640-680C and the circulating cooling water flux of 0.9 m3/h, the semi-solid A356 aluminum alloy slurry with spherical primary ?(Al) grains can be obtained, whose shape factors are between 0.78 and 0.86 and the grain diameter can reach 48-68 ?m. When the pouring temperatures are at 660-680C, only a very thin solidified shell remains inside the serpentine channel and can be removed easily. When the serpentine channel is cooled with circulating water, the microstructure of the semi-solid slurry can be improved, and the serpentine channel is quickly cooled to room temperature after the completion of one pouring. In terms of the productivity of the special equipment, the water-cooled serpentine channel is economical and efficient.

Chen, Zheng-Zhou; Mao, Wei-Min; Wu, Zong-Chuang

2012-01-01

107

IAEA coordinated research project on thermal-hydraulics of Supercritical Water-Cooled Reactors (SCWRs)  

SciTech Connect

The Supercritical Water-Cooled Reactor (SCWR) is an innovative water-cooled reactor concept, which uses supercritical pressure water as reactor coolant. It has been attracting interest of many researchers in various countries mainly due to its benefits of high thermal efficiency and simple primary systems, resulting in low capital cost. The IAEA started in 2008 a Coordinated Research Project (CRP) on Thermal-Hydraulics of SCWRs as a forum to foster the exchange of technical information and international collaboration in research and development. This paper summarizes the activities and current status of the CRP, as well as major progress achieved to date. At present, 15 institutions closely collaborate in several tasks. Some organizations have been conducting thermal-hydraulics experiments and analysing the data, and others have been participating in code-to-test and/or code-to-code benchmark exercises. The expected outputs of the CRP are also discussed. Finally, the paper introduces several IAEA activities relating to or arising from the CRP. (authors)

Yamada, K. [Vienna International Centre, P.O. Box 100, 1400 Vienna (Austria); Aksan, S. N. [International Atomic Energy Agency, 1400 Vienna (Austria)

2012-07-01

108

Improvement in understanding of natural circulation phenomena in water cooled nuclear power plants  

Microsoft Academic Search

The IAEA has organized a coordinated research project (CRP) on Natural Circulation Phenomena, Modelling, and Reliability of Passive Systems That Utilize Natural Circulation. Specific objectives of CRP were to (i) establish the status of knowledge: reactor start-up and operation, passive system initiation and operation, flow stability, 3-D effects, and scaling laws, (ii) investigate phenomena influencing reliability of passive natural circulation

Jong-Ho Choi; John Cleveland; Nusret Aksan

2011-01-01

109

Feasibility Study of Supercritical Light Water Cooled Reactors for Electric Power Production  

SciTech Connect

The supercritical water reactor (SCWR) has been the object of interest throughout the nuclear Generation IV community because of its high potential: a simple, direct cycle, compact configuration; elimination of many traditional LWR components, operation at coolant temperatures much higher than traditional LWRs and thus high thermal efficiency. It could be said that the SWR was viewed as the water counterpart to the high temperature gas reactor.

Philip MacDonald; Jacopo Buongiorno; James Sterbentz; Cliff Davis; Robert Witt; Gary Was; J. McKinley; S. Teysseyre; Luca Oriani; Vefa Kucukboyaci; Lawrence Conway; N. Jonsson: Bin Liu

2005-02-13

110

Passive decay heat removal system for water-cooled nuclear reactors  

DOEpatents

A passive decay-heat removal system for a water-cooled nuclear reactor employs a closed heat transfer loop having heat-exchanging coils inside an open-topped, insulated box located inside the reactor vessel, below its normal water level, in communication with a condenser located outside of containment and exposed to the atmosphere. The heat transfer loop is located such that the evaporator is in a position where, when the water level drops in the reactor, it will become exposed to steam. Vapor produced in the evaporator passes upward to the condenser above the normal water level. In operation, condensation in the condenser removes heat from the system, and the condensed liquid is returned to the evaporator. The system is disposed such that during normal reactor operations where the water level is at its usual position, very little heat will be removed from the system, but during emergency, low water level conditions, substantial amounts of decay heat will be removed.

Forsberg, Charles W. (Oak Ridge, TN)

1991-01-01

111

Molecular Dynamics Simulations of Aqueous and Confined Systems Relevant to the Supercritical Water Cooled Nuclear Reactor  

NASA Astrophysics Data System (ADS)

Supercritical water (SCW) is the intended heat transfer fluid and potential neutron moderator in the proposed GEN-IV Supercritical Water Cooled Reactor (SCWR). The oxidative environment poses challenges in choosing appropriate design materials, and the behaviour of SCW within crevices of the passivation layer is needed for developing a corrosion control strategy to minimize corrosion. Molecular Dynamics simulations have been employed to obtain diffusion coefficients, coordination number and surface density characteristics, of water and chloride in nanometer-spaced iron hydroxide surfaces. Diffusion models for hydrazine are evaluated along with hydration data. Results demonstrate that water is more likely to accumulate on the surface at low density conditions. The effect of confinement on the water structure diminishes as the gap size increases. The diffusion coefficient of chloride decreases with larger surface spacing. Clustering of water at the surface implies that the SCWR will be most susceptible to pitting corrosion and stress corrosion cracking.

Kallikragas, Dimitrios Theofanis

112

A Qualitative Assessment of Thorium-Based Fuels in Supercritical Pressure Water Cooled Reactors  

SciTech Connect

The requirements for the next generation of reactors include better economics and safety, waste minimization (particularly of the long-lived isotopes), and better proliferation resistance (both intrinsic and extrinsic). A supercritical pressure water cooled reactor has been chosen as one of the lead contenders as a Generation IV reactor due to the high thermal efficiency and compact/simplified plant design. In addition, interest in the use of thorium-based fuels for Generation IV reactors has increased based on the abundance of thorium, and the minimization of transuranics in a neutron flux; as plutonium (and thus the minor actinides) is not a by-product in the thorium chain. In order to better understand the possibility of the combination of these concepts to meet the Generation IV goals, the qualitative burnup potential and discharge isotopics of thorium and uranium fuel were studied using pin cell analyses in a supercritical pressure water cooled reactor environment. Each of these fertile materials were used in both nitride and metallic form, with light water reactor grade plutonium and minor actinides added. While the uranium-based fuels achieved burnups that were 1.3 to 2.7 times greater than their thorium-based counterparts, the thorium-based fuels destroyed 2 to 7 times more of the plutonium and minor actinides. The fission-to-capture ratio is much higher in this reactor as compared to PWRs and BWRs due to the harder neutron spectrum, thus allowing more efficient destruction of the transuranic elements. However, while the uranium-based fuels do achieve a net depletion of plutonium and minor actinides, the breeding of these isotopes limits this depletion; especially as compared to the thorium-based fuels.

Weaver, Kevan Dean; Mac Donald, Philip Elsworth

2002-10-01

113

The effectiveness of power-generating complexes constructed on the basis of nuclear power plants combined with additional sources of energy determined taking risk factors into account  

NASA Astrophysics Data System (ADS)

The effectiveness of combining nuclear power plants equipped with water-cooled water-moderated power-generating reactors (VVER) with other sources of energy within unified power-generating complexes is analyzed. The use of such power-generating complexes makes it possible to achieve the necessary load pickup capability and flexibility in performing the mandatory selective primary and emergency control of load, as well as participation in passing the night minimums of electric load curves while retaining high values of the capacity utilization factor of the entire power-generating complex at higher levels of the steam-turbine part efficiency. Versions involving combined use of nuclear power plants with hydrogen toppings and gas turbine units for generating electricity are considered. In view of the fact that hydrogen is an unsafe energy carrier, the use of which introduces additional elements of risk, a procedure for evaluating these risks under different conditions of implementing the fuel-and-hydrogen cycle at nuclear power plants is proposed. Risk accounting technique with the use of statistical data is considered, including the characteristics of hydrogen and gas pipelines, and the process pipelines equipment tightness loss occurrence rate. The expected intensities of fires and explosions at nuclear power plants fitted with hydrogen toppings and gas turbine units are calculated. In estimating the damage inflicted by events (fires and explosions) occurred in nuclear power plant turbine buildings, the US statistical data were used. Conservative scenarios of fires and explosions of hydrogen-air mixtures in nuclear power plant turbine buildings are presented. Results from calculations of the introduced annual risk to the attained net annual profit ratio in commensurable versions are given. This ratio can be used in selecting projects characterized by the most technically attainable and socially acceptable safety.

Aminov, R. Z.; Khrustalev, V. A.; Portyankin, A. V.

2015-02-01

114

Fabrication of gas turbine water-cooled composite nozzle and bucket hardware employing plasma spray process  

DOEpatents

In the method for fabrication of water-cooled composite nozzle and bucket hardware for high temperature gas turbines, a high thermal conductivity copper alloy is applied, employing a high velocity/low pressure (HV/LP) plasma arc spraying process, to an assembly comprising a structural framework of copper alloy or a nickel-based super alloy, or combination of the two, and overlying cooling tubes. The copper alloy is plamsa sprayed to a coating thickness sufficient to completely cover the cooling tubes, and to allow for machining back of the copper alloy to create a smooth surface having a thickness of from 0.010 inch (0.254 mm) to 0.150 inch (3.18 mm) or more. The layer of copper applied by the plasma spraying has no continuous porosity, and advantageously may readily be employed to sustain a pressure differential during hot isostatic pressing (HIP) bonding of the overall structure to enhance bonding by solid state diffusion between the component parts of the structure.

Schilke, Peter W. (4 Hempshire Ct., Scotia, NY 12302); Muth, Myron C. (R.D. #3, Western Ave., Amsterdam, NY 12010); Schilling, William F. (301 Garnsey Rd., Rexford, NY 12148); Rairden, III, John R. (6 Coronet Ct., Schenectady, NY 12309)

1983-01-01

115

Improvement in Stability of SPring-8 Standard X-Ray Monochromators with Water-Cooled Crystals  

SciTech Connect

SPring-8 standard double-crystal monochromators containing water-cooled crystals were stabilized to a sufficient level to function as a part of optics components to supply stable microfocused x-ray beams, by determining causes of the instability and then removing them. The instability was caused by two factors--thermal deformation of fine stepper stages in the monochromator, which resulted in reduction in beam intensity with time, and vibrations of coolant supply units and vacuum pumps, which resulted in fluctuation in beam intensity. We remodeled the crystal holders to maintain the stage temperatures constant with water, attached x-ray and electron shields to the stages in order to prevent their warming up, introduced accumulators in the water circuits to absorb pressure pulsation, used polyurethane tubes to stabilize water flow, and placed rubber cushions under scroll vacuum pumps. As a result, the intensity reduction rate of the beam decreased from 26% to 1% per hour and the intensity fluctuation from 13% to 1%. The monochromators were also modified to prevent radiation damage to the crystals, materials used as a water seal, and motor cables.

Yamazaki, Hiroshi; Shimizu, Nobtaka; Kumasaka, Takashi; Koganezawa, Tomoyuki; Sato, Masugu; Hirosawa, Ichiro; Senba, Yasunori; Ohashi, Haruhiko; Goto, Shunji [Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1, Kouto, Sayo-cho, Hyogo 679-5198 (Japan); Shimizu, Yasuhiro; Miura, Takanori; Tanaka, Masayuki; Kishimoto, Hikaru; Matsuzaki, Yasuhisa [Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1, Kouto, Sayo-cho, Hyogo 679-5198 (Japan); SPring-8 Service Co., Ltd., 2-23-1, Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1205 (Japan); Kawano, Yoshiaki; Yamamoto, Masaki; Ishikawa, Tetsuya [RIKEN SPring-8 Center, 1-1-1, Kouto, Sayo-cho, Hyogo 679-5148 (Japan)

2010-06-23

116

Pacific Northwest Power Supply Adequacy Assessment  

E-print Network

plants. The majority of potential future problems are short-term capacity shortfalls. The most critical from 3,200 to 1,700 megawatts, mainly due to the retirement of coastal water-cooled thermal power

117

Heat-transfer phenomena in water-cooled zinc-fuming furnace jackets  

NASA Astrophysics Data System (ADS)

In the zinc slag-fuming process, zinc is removed from lead blast furnace slag by reduction with a coal-air mixture injected into the slag through submerged tuyeres. The furnace is constructed of water-cooled jackets which freeze a slag layer and contain the bath. This greatly reduces vessel wear caused by the violently agitated and corrosive bath. The jackets, however, fail due to the formation of cracks which grow from the slag face through the working face of the jacket to the water channel. In this study, in-plant measurements and mathematical modeling of heat transfer in the jackets have been combined to elucidate the mechanism of failure. The working face of a water jacket was instrumented with thermocouples and installed in a fuming furnace at the Trail smelter of Cominco Ltd., Trail, BC. Measurements revealed the presence of large thermal transients or temperature spikes in the panel in the region immediately above the tuyeres. These were generally observed during charging and tapping of the furnace and are likely associated with disturbances on the surface of the bath or gas injection effects when the liquid level is low. Temperatures at the midthickness were seen to rise by as much as 180 C above the steady-state level. Under these conditions, low-cycle fatigue may lead to crack formation and propagation. A mathematical modeling analysis of the transient freezing phenomena indicates that the temperature spikes are associated with sudden slag falloff and direct contact of molten slag on the jacket. In order to reduce slag falloff, an increased number of anchoring fins should be used in critical areas.

Scholey, K. E.; Richards, G. G.; Samarasekera, I. V.

1991-04-01

118

A Cu-Cr alloy with nano and microscale Cr particles produced in a water-cooled copper mold  

Microsoft Academic Search

Microstructures have profound effects on the hardness and strength of Cu-Cr alloys. The microstructures of a Cu-Cr alloy cast\\u000a in a water-cooled copper mold were studied in the present work. The scanning electron microscopy (SEM) results show that there\\u000a are the copper matrix saturated with chromium, spherical precipitates of chromium separated from liquid phase during cooling\\u000a before the initiation of

Seyyed Mohammd Hossein Hejazi; Fatemeh Majidi; Gholam Hossein Akbari

2010-01-01

119

Characterization and evaluation of the hydraulic activity of water-cooled slag and air-cooled slag  

Microsoft Academic Search

Water-cooled slag (WS) and air-cooled slag (AS) were characterized chemically and mineralogically and a comparative study of their reactivities with 10% and 20% lime was conducted using an accelerated chemical method. Both types of slag have the same chemical composition, but WS is completely vitreous materials and the main mineral composition of AS is gehlenite. The kinetics of the WSlime

N. Y Mostafa; S. A. S El-Hemaly; E. I Al-Wakeel; S. A El-Korashy; P. W Brown

2001-01-01

120

Correlations for Predicting the Air-Side Nusselt Numbers and Friction Factors in Chilled-Water Cooling Coils  

Microsoft Academic Search

An experimental study was conducted to determine Nusselt numbers and friction factors on the air side of wavy-finned, chilled-water cooling coils. General correlations of the dry-surface Nusselt numbers and friction factors were developed from the data obtained from five different cooling coils. A comparison of the Nusselt number correlation to data from the literature revealed that the correlation was generally

D. R. Mirth; S. Ramadhyani

1994-01-01

121

Hepatic resections using a water-cooled, high-density, monopolar device: a new technology for safer surgery  

Microsoft Academic Search

Several techniques and devices have recently been developed in an effort to allow safer liver resections and avoid intraoperative blood loss. The aim of this study was to analyze our initial experience with hepatic resections using a new water-cooled, high-density, monopolar devicethe Tissuelink Monopolar Floating Ball (Tissuelink Medical, Inc., Dover, NH)in order to avoid bleeding during hepatic surgery. We analyzed

Isidoro Di Carlo; Francesco Barbagallo; Adriana Toro; Maria Sofia; Tommaso Guastella; Ferdinando Latteri

2004-01-01

122

Prediction of critical heat flux in water-cooled plasma facing components using computational fluid dynamics.  

SciTech Connect

Several commercial computational fluid dynamics (CFD) codes now have the capability to analyze Eulerian two-phase flow using the Rohsenow nucleate boiling model. Analysis of boiling due to one-sided heating in plasma facing components (pfcs) is now receiving attention during the design of water-cooled first wall panels for ITER that may encounter heat fluxes as high as 5 MW/m2. Empirical thermalhydraulic design correlations developed for long fission reactor channels are not reliable when applied to pfcs because fully developed flow conditions seldom exist. Star-CCM+ is one of the commercial CFD codes that can model two-phase flows. Like others, it implements the RPI model for nucleate boiling, but it also seamlessly transitions to a volume-of-fluid model for film boiling. By benchmarking the results of our 3d models against recent experiments on critical heat flux for both smooth rectangular channels and hypervapotrons, we determined the six unique input parameters that accurately characterize the boiling physics for ITER flow conditions under a wide range of absorbed heat flux. We can now exploit this capability to predict the onset of critical heat flux in these components. In addition, the results clearly illustrate the production and transport of vapor and its effect on heat transfer in pfcs from nucleate boiling through transition to film boiling. This article describes the boiling physics implemented in CCM+ and compares the computational results to the benchmark experiments carried out independently in the United States and Russia. Temperature distributions agreed to within 10 C for a wide range of heat fluxes from 3 MW/m2 to 10 MW/m2 and flow velocities from 1 m/s to 10 m/s in these devices. Although the analysis is incapable of capturing the stochastic nature of critical heat flux (i.e., time and location may depend on a local materials defect or turbulence phenomenon), it is highly reliable in determining the heat flux where boiling instabilities begin to dominate. Beyond this threshold, higher heat fluxes lead to the boiling crisis and eventual burnout. This predictive capability is essential in determining the critical heat flux margin for the design of complex 3d components.

Bullock, James H.; Youchison, Dennis Lee; Ulrickson, Michael Andrew

2010-11-01

123

Compatibility of water-cooled chromia-containing refractories with a high iron oxide acidic coal-ash slag at 1575 C  

Microsoft Academic Search

Sixteen water-cooled refractories were exposed to a synthetic high iron oxide acidic coal slag at 1575 C. The importance\\u000a of high chromia content and density in minimizing corrosive attack was evident. The beneficial effect of water cooling was\\u000a also clearly demonstrated by the difference in corrosion and penetration between full- and 1\\/2- length specimens. All of the\\u000a refractories were found

Christopher R. Kennedy

1981-01-01

124

Standardisation of water-moderated 241Am-Be neutron source using De Pangher neutron long counter: experimental and Monte Carlo modelling.  

PubMed

A convenient neutron source is made for calibration of neutron survey instruments and personal dosimeters that are used in various nuclear installations such as fuel reprocessing, waste management, fuel fabrication and oil and well logging facilities, etc. This source consists of a bare (241)Am-Be neutron source placed at the centre of a 15-cm radius stainless steel spherical shell filled with distilled water. This paper describes the standardisation of the source at Bhabha Atomic Research Centre, using De Pangher neutron long counter both experimentally and using the Monte Carlo simulation. The ratio of neutron yield of water moderated to the bare (241)Am-Be neutron source was found to be 0.573. From the simulation, the neutron-fluence-weighted average energy of water-moderated (241)Am-Be source (fluence-weighted average energy of 2.25 MeV, dose-weighted average energy of 3.55 MeV) was found to be nearly the same as that of a (252)Cf source (fluence-weighted average energy of 2.1 MeV, dose-weighted average energy of 2.3 MeV). This source can be used for calibration in addition to (252)Cf, to study the variation in response of neutron monitoring instruments. PMID:21498862

Ghodke, Shobha; Kumari, Sujatha; Singh, Yashoda; Sathian, V; Mahant, A K; Sharma, D N

2012-02-01

125

Optimization of water-cooled chiller system with load-based speed control  

Microsoft Academic Search

This study investigates the energy performance of chiller and cooling tower systems integrated with variable condenser water flow and optimal speed control for tower fans and condenser water pumps. Thermodynamic-behaviour chiller and cooling tower models were developed to assess how different control methods of cooling towers and condenser water pumps influence the trade-off between the chiller power, pump power, fan

F. W. Yu; K. T. Chan

2008-01-01

126

Fabrication of water-cooled laser silicon mirror by direct laser sintering.  

PubMed

Coppery heat sink with micro pores and Sub-millimeter channel has been fabricated by direct laser sintering on the back of the silicon mirror. To verify the heat dissipation capability of the fabricated heat sink, a Twyman-Green interferometer was employed to measure the thermal deformation of the silicon mirror radiated by a high power laser. It is shown that the thermal deformation of the mirror increases with the irradiating time and laser intensity. The heat balance can be achieved after several seconds of laser irradiation even when the net absorbed laser power density is up to 5.3 10(5) W/m(2). The time for reaching the heat balance also increases with the laser intensity. The maximum thermal deformation of the mirror is 0.65 m if the net absorbed laser power density is 5.3 10(5) W/m(2). PMID:24787872

He, Chongwen; Zhu, Haihong; Hu, Panpan

2014-04-21

127

Spent nuclear fuel project cold vacuum drying facility tempered water and tempered water cooling system design description  

SciTech Connect

This document provides the System Design Description (SDD) for the Cold Vacuum Drying Facility (CVDF) Tempered Water (TW) and Tempered Water Cooling (TWC) System . The SDD was developed in conjunction with HNF-SD-SNF-SAR-002, Safety Analysis Report for the Cold Vacuum Drying Facility, Phase 2, Supporting Installation of Processing Systems (Garvin 1998), The HNF-SD-SNF-DRD-O02, 1998, Cold Vacuum Drying Facility Design Requirements, and the CVDF Design Summary Report. The SDD contains general descriptions of the TW and TWC equipment, the system functions, requirements and interfaces. The SDD provides references for design and fabrication details, operation sequences and maintenance. This SOD has been developed for the SNFP Operations Organization and shall be updated, expanded, and revised in accordance with future design, construction and startup phases of the CVDF until the CVDF final ORR is approved.

IRWIN, J.J.

1998-11-30

128

Online adaptive control for optimizing variable-speed pumps of indirect water-cooled chilling systems  

Microsoft Academic Search

An online control strategy is developed to optimize the speed of variable speed condenser cooling water pumps by resetting their pressure set-point, which includes an adaptive and a derivative control strategy. Optimal control is achieved by adjusting the pressure set-point according to the estimated derivative of the total power with respect to pressure. The adaptive strategy identifies the changes of

Shengwei Wang; John Burnett

2001-01-01

129

Nuclear and Thermal Analyses of Supercritical-water-cooled Solid Breeder Blanket for Fusion DEMO Reactor  

Microsoft Academic Search

Within a design study of a fusion DEMO reactor aiming at demonstrating technologies of fusion power plant, supercritical water is applied as a coolant of solid breeder blanket to attain high thermal efficiency. The blanket has multi-layer composed of solid breeder pebbles (Li2O) and neutron multiplier pebbles (Be) which are radially separated by cooling panels. The first wall and the

Yoshihiko YANAGI; Satoshi SATO; Mikio ENOEDA; Toshihisa HATANO; Shigeto KIKUCHI; Toshimasa KURODA; Yasuo KOSAKU; Yoshihiro OHARA

2001-01-01

130

10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors  

...leakage through all potential leakage paths including containment welds, valves, fittings, and components which penetrate containment...rate through all tested leakage paths, including containment welds, valves, fittings, and components that penetrate the...

2014-01-01

131

10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors  

Code of Federal Regulations, 2012 CFR

...leakage through all potential leakage paths including containment welds, valves, fittings, and components which penetrate containment...rate through all tested leakage paths, including containment welds, valves, fittings, and components that penetrate the...

2012-01-01

132

Nuclear characteristics of a fissioning uranium plasma test reactor with light-water cooling  

NASA Technical Reports Server (NTRS)

An analytical study was performed to determine a design configuration for a cavity test reactor. Test section criteria were that an average flux of 10 to the 15th power neutrons/sq cm/sec (E less than or equal to 0.12 eV) be supplied to a 61-cm-diameter spherical cavity at 200-atm pressure. Design objectives were to minimize required driver power, to use existing fuel-element technology, and to obtain fuel-element life of 10 to 100 full-power hours. Parameter calculations were made on moderator region size and material, driver fuel arrangement, control system, and structure in order to determine a feasible configuration. Although not optimized, a configuration was selected which would meet design criteria. The driver fuel region was a cylindrical annular region, one element thick, of 33 MTR-type H2O-cooled elements (Al-U fuel plate configuration), each 101 cm long. The region between the spherical test cavity and the cylindrical driver fuel region was Be (10 vol. % H2O coolant) with a midplane dimension of 8 cm. Exterior to the driver fuel, the 25-cm-thick cylindrical and axial reflectors were also Be with 10 vol. % H2O coolant. The entire reactor was contained in a 10-cm-thick steel pressure vessel, and the 200-atm cavity pressure was equalized throughout the driver reactor. Fuel-element life was 50 hr at the required driver power of 200 MW. Reactor control would be achieved with rotating poison drums located in the cylindrical reflector region. A control range of about 18 percent delta k/k was required for reactor operation.

Whitmarsh, C. L., Jr.

1973-01-01

133

Prototype of electric vehicle drive with twin water-cooled wheel direct drive motors  

Microsoft Academic Search

The availability of new high-energy permanent magnets at a reasonable cost has opened up the possibility of developing very compact brushless permanent magnet motors with substantially improved overload capability for wheel direct drive applications. Concerning the development of an electric propulsion system for a newly-conceived dual-power city car, this paper discusses the design, construction and laboratory testing of a twin

F. Caricchi; F. Crescimbini; A. Di Napoli; M. Marcheggiani

1996-01-01

134

High-enthalpy, water-cooled and thin-walled ICP sources characterization and MHD optimization  

NASA Astrophysics Data System (ADS)

The development of the inductively driven plasma wind tunnel PWK3, which enables the electrodeless generation of high-enthalpy plasmas for the development of heat shield materials required for space vehicles performing entry manoeuvres in the atmospheres of Venus, Earth and Mars, is described. The facility with its modular inductive plasma generators allows operation with gases such as carbon dioxide, air, oxygen and nitrogen and was qualified for thermal plasma powers up to 60 kW. Previously developed models for determining plasma properties and plasma source related characteristics enable a maximum plasma power in combination with long operational periods using different operational gases and gas mixtures. This is achieved by an optimization using the optimum operational frequency, a minimization of field losses using very thin plasma tube wall thicknesses and the successful application of MHD effects. Based on the solved cylinder problem for ICPs, a one-dimensional model for radial Lorentz forces and magnetic pressure has been developed. Here, a synthesis of previously published data and works is made where the new algebraic model for the calculation of Lorentz forces and magnetic pressures in an ICP was used and applied to experimental data. In addition, results from the model using the experimental data are shown to be consistent and, in addition, a comparison with a simpler model based on the well-known exponential approach for ICPs showed that the simpler model is covered without fail by the new model. The new model also states that there is a maximum of the Lorentz forces over the damping parameter d/? (plasma diameter divided by skin depth) which almost corresponds with the position of the maximum plasma power of the cylindric model for ICPs. For the magnetic pressure the position of the maximum pressure is identical to the value for d/? for the maximum plasma power.

Herdrich, G.; Petkow, D.

2008-06-01

135

Structure and Performance of a 600MWe Supercritical CFB Boiler with Water Cooled Panels  

NASA Astrophysics Data System (ADS)

The circulating fluidized bed (CFB) combustion technology is one of the approved clean combustion technologies, and the power supply efficiency can be improved combining with the supercritical technology. A 600MWe supercritical CFB boiler is introduced in this paper. This boiler is designed based on the success of 300 MWe CFB boilers, which has a single furnace with three cyclones without external heat exchangers. There are twin furnaces and twin air distributors in the boiler. The water walls of the twin furnace above dense bed combines to a common fence wall with some channels to balance the pressure of the two furnaces. The smooth tubes are adopted in membrane water wall with mixing header. Six cyclones are located beside the furnace as well as six loopseals and six external heat exchangers. The hydrodynamic characteristic of water wall is available with the modeling prediction. And the performance of the 600MWe supercritical CFB boiler is also investigated.

Li, Y.; Nie, L.; Hu, X. K.; Yue, G. X.; Li, W. K.; We, Y. X.; Lu, J. F.; Che, D. F.

136

Melting Mechanism of Water-Cooled Billet-Type Bottom Electrode of Direct Current Arc Furnace: A Numerical Approach  

NASA Astrophysics Data System (ADS)

The direct current (DC) furnace, the earliest type of the electric arc furnace (EAF), was popularized at the end of the 1980s. Even in its heyday, there were always doubts about its superiority due to some imperfections of the DC furnace ( e.g., the problems of the bottom electrode system). The water-cooled billet electrode, which is classified as one of the four types of the bottom electrodes, has been in use for more than two decades. However, so far its melting mechanism has not been well understood. A sophisticated numerical model was thus constructed by coupling the heat transfer and the fluid flow, and taking into account the electromagnetic effect as well as the influence of the gap between the billet and the copper jacket. The observed phenomena could readily be explained using the model. The computed results show that the axial component of the electromagnetic force plays an essential role in driving the strong flow within the electrode hole, and that the Joule effect does not contribute the majority of the heat taken away by cooling water. An important conclusion is reached that there is a double-edged effect by changing the billet diameter. Accordingly, a modification of the billet shape is suggested, i.e., a diameter-variable structure, which should greatly assist in improving the thermal state of the billet.

Liu, X.; Zhou, J. P.; Shi, H. Z.; Yang, Y. L.; Yang, B. Q.; Hu, A. M.; Du, Z. H.; Yuan, F.; Wang, Y. P.

2008-10-01

137

RESONANCE CONTROL FOR THE COUPLED CAVITY LINAC AND DRIFT TUBE LINAC STRUCTURES OF THE SPALLATION NEUTRON SOURCE LINAC USING A CLOSED-LOOP WATER COOLING SYSTEM  

SciTech Connect

The Spallation Neutron Source (SNS) is a facility being designed for scientific and industrial research and development. SNS will generate and use neutrons as a diagnostic tool for medical purposes, material science, etc. The neutrons will be produced by bombarding a heavy metal target with a high-energy beam of protons, generated and accelerated with a linear particle accelerator, or linac. The low energy end of the linac consists of two room temperature copper structures, the drift tube linac (DTL), and the coupled cavity linac (CCL). Both of these accelerating structures use large amounts of electrical energy to accelerate the protons to an energy of 185 MeV. Approximately 60-80% of the electrical energy is dissipated in the copper structure and must be removed. This is done using specifically designed water cooling passages within the linac's copper structure. Cooling water is supplied to these cooling passages by specially designed resonance control and water cooling systems.

Bernardin, J. D. (John D.); Brown, R. L. (Richard L.); Brown, S. K. (Stanley K.); Bustos, G. R. (Gerald R.); Crow, M.L. (Martin L.); Gregory, W. S.; Hood, M. E. (Michael E.); Jurney, J. D. (James D.); Medalen, I. (Ivan); Owen, A. C. (Albert C.); Weiss, Robert E.

2001-01-01

138

Ground Water Cooling System  

E-print Network

Based on a thorough study of products and anticipated growth, the Turbine and Generator Division of Westinghouse Canada Inc. concluded that a component feeder plant for fabrication and machining of turbine components was required. This facility now...

Greaves, K.; Chave, G. H.

1984-01-01

139

Jet-type, water-cooled heat sink that yields 255-W continuous-wave laser output at 808 nm from a 1-cm laser diode bar  

Microsoft Academic Search

A newly designed jet-type, water-cooled heat sink (the funryu heat sink, meaning fountain flow in Japanese) yielded 255-W cw laser output at 808 nm from a 1-cm bar made from InGaAsP\\/InGaP quantum-well active layers with a 67% fill factor [70 quantum-well laser diode (LD) array along the 1-cm bar]. A funryu heat sink measuring 1.1 mm in thickness gave the

Hirofumi Miyajima; Hirofumi Kan; Takeshi Kanzaki; Shin-Ichi Furuta; Masanobu Yamanaka; Yasukazu Izawa; Sadao Nakai

2004-01-01

140

Microstructural characteristics and thermal stability of a NiAl-based near-eutectic alloy fabricated by water-cooled copper mold method  

Microsoft Academic Search

The microstructural characteristics and thermal stability of a rapidly solidified NiAlCr(Mo)Hf near-eutectic alloy fabricated by water-cooled copper mold method were investigated by SEM, EDAX, TEM, and HIP treatment. Rapid solidification resulted in the following effects which encompass refinement of the microstructure: cell size, lamellar spacing and precipitates, deviation from the equilibrium composition, solubility extension, and a transition from a Heusler

Hu-tian Li; Jian-ting Guo; Kai-wen Huai; Heng-qiang Ye

2007-01-01

141

Experimental Study on Temperature Coefficient of Reactivity in Light-Water-Moderated and Heavy-Water-Reflected Cylindrical Core Loaded with Highly-Enriched-Uranium or Medium-Enriched-Uranium Fuel  

Microsoft Academic Search

By using the Kyoto University Critical Assembly (KUCA), a series of critical experiments was performed to measure the temperature coefficient of reactivity in a light-water-moderated and heavy-water-reflected cylindrical core loaded with highly-enriched-uranium (HEU) or medium- enriched-uranium (MEU) fuel. The measurement was performed for the approximately 20 to 70C range to examine the effects of the size of light-water region in

Seiji SHIROYA; Masaaki MORI; Tsuyoshi MISAWA; Masatoshi HAYASHI; Keiji KOBAYASHI; Keiji KANDA

1995-01-01

142

Actively cooled plasma facing components for long pulse high power operation  

Microsoft Academic Search

This paper reviews the development of heat removal technology for plasma facing components (PFCs) and focuses on water-cooled PFCs for near term, high power applications and the use of the tungsten (W), carbon (C), and beryllium (Be) as the preferred armor materials. There are also brief summaries of developments in helium-cooled PFCs and applications of free liquid surfaces. Water-cooled PFCs

R. E. Nygren

2002-01-01

143

Water Powered Tools  

NASA Technical Reports Server (NTRS)

Space Spin-Offs, Inc. under a contract with Lewis Research Center and Marshall Space Flight Center produced a new water-powered saw that cuts through concrete and steel plate reducing danger of explosion or electric shock in rescue and other operations. In prototype unit efficient water-powered turbine drives an 8 inch diameter grinding disk at 6,600 rpm. Exhaust water cools disk and workpiece quenching any sparks produced by cutting head. At maximum power, tool easily cuts through quarter inch steel plate. Adapter heads for chain saws, impact wrenches, heavy duty drills, and power hack saws can be fitted.

1976-01-01

144

State of metallic surfaces in systems of nuclear power plants with a series 1000 high-powered-water-cooled channel reactor after assembly  

Microsoft Academic Search

We investigated the state of the surfaces by examining, photographing, and collecting samples of surface contaminants at the open ends of piping system blocks. We performed a phase analysis of the samples taken in a 3,-resonance YaGRS-4M spectrometer. We determined the specific contamination of the inner surfaces of equipment and piping system by a weight method by mechanically removing oxides

V. M. Sedov; P. G. Krutikov; A. I. Grushanin; S. T. Zolotukhin; Yu. O. Zakharzhevskii; A. P. Eperin

1981-01-01

145

71 FR 12782 - Licenses, Certifications, and Approvals for Nuclear Power Plants  

Federal Register 2010, 2011, 2012, 2013

...programs and procedures. The manufactured...incorporate nuclear power facilities by...practice and procedure, Environmental...materials, Nuclear power plants and reactors...local zoning laws. For other than...light-water-cooled nuclear power reactors, the...shall identify procedures for...

2006-03-13

146

Analysis of regularly perturbed lattices and reaction rate distributions from TIC experiments for X7 lattices  

Microsoft Academic Search

Temporary International Collective (TIC) was established in 1972 by an agreement among seven countries, namely, Bulgaria, Czechoslovakia, Germany, Hungary, Poland, Romania and Union of Soviet Socialist Republics. The main objective of TIC was to provide the experimental data for the reactor physics analysis of water cooled and water moderated power reactors (WWER). Extensive experimental work for different core configurations was

A. Ramakrishna; V. Jagannathan; R. P. Jain

2011-01-01

147

Evaluation of coal-gasification - combustion-turbine power plants emphasizing low water consumption  

SciTech Connect

A cost and performance study was made of several integrated power plants using coal gasification technology now in advanced development and combustion turbines for power generation. The principal emphasis was placed on studying plants using air cooling and comparing costs and performance of those plants with water-cooled coal gasification-combined-cycle (GCC) and conventional coal-fired power plants. The major objective was to determine whether cost and performance penalties would be prohibitive for air-cooled plants that use yet-to-be-developed coal gasifiers and commercially available combustion turbines for topping cycle power. The results indicate the following: air-cooled GCC plants using conceptual designs of either the Texaco or the British Gas Corporation (BGC) slaging gasifier could have coal-to-net electric power efficiencies equivalent to that of a water-cooled conventional coal-fired plant; the air-cooled GCC plants could produce electricity at busbar cost 1 to 3 mills per kWh (1980 dollars) less than busbar cost in a water-cooled conventional plant and only up to 2 mills per kWh higher than busbar cost in a water-cooled Texaco GCC plant; and even a simple-cycle regenerative combustion turbine plant fueled with gas from the BGC gasifier could have a coal-to-net electric power efficiency of over 30% and a busbar cost competitive with that in a water cooled conventional plant. The principal reason that air-cooled power plants using combustion turbines could be competitive with conventional water-cooled, coal-fired steam plants is that a majority of net power is produced by the combustion turbines, which require no cooling water. This, in turn, leads to a reduced cost and performance penalty when bottoming steam-cycle condensers are air-cooled.

Cavazo, R.; Clemmer, A.B.; de la Mora, J.A.; Grisso, J.R.; Klumpe, H.W.; Meissner, R.E.; Musso, A.; Roszkowski, T.R.

1982-01-01

148

OSCAR Compiler and API for High Performance Low Power Multicores  

E-print Network

Supercomputers Earth Simulator:40TFLOPS, 2002, 5120 vector proc. BG/Q (A2:16cores) Water Cooled20PFLOPS, 3-4MW) Beside Subway Waseda Station, Near Waseda Univ. Main Campus 3 Hitachi SR16000: Power7 128coreSMP Fujitsu M9000 SPARC VII 256 core SMP #12;Cancer Treatment Carbon Ion Radiotherapy Environment Lives

Kasahara, Hironori

149

OSCAR Compiler for Automatic Parallelization and Power Reduction  

E-print Network

) Beside Subway Waseda Station, Near Waseda Univ. Main Campus 2 Hitachi SR16000: Power7 128coreSMP Fujitsu M9000 SPARC VII 256 core SMP #12;Cancer Treatment Carbon Ion Radiotherapy Environment Lives Supercomputers Earth Simulator:40TFLOPS, 2002, 5120 vector proc. BG/Q (A2:16cores) Water Cooled20PFLOPS, 3-4MW

Kasahara, Hironori

150

Modern HVDC thyristor valves for China's electric power system  

Microsoft Academic Search

The technology of HVDC thyristor valves available in China since the mid-1980s has been continually updated in line with international developments. The thyristor valves for the Guizhou-Guangdong HVDC Project combine direct-light-triggered thyristor (LTT) technology and a proven valve design featuring a minimized number of power components, corrosion free water cooling, and fire hardened components.

J. Holweg; H. P. Lips; B. Q. Tu; M. Uder; Peng Baoshu; Zhang Yeguang

2002-01-01

151

Feasibility study for use of the natural convection shutdown heat removal test facility (NSTF) for VHTR water-cooled RCCS shutdown.  

SciTech Connect

In summary, a scaling analysis of a water-cooled Reactor Cavity Cooling System (RCCS) system was performed based on generic information on the RCCS design of PBMR. The analysis demonstrates that the water-cooled RCCS can be simulated at the ANL NSTF facility at a prototypic scale in the lateral direction and about half scale in the vertical direction. Because, by necessity, the scaling is based on a number of approximations, and because no analytical information is available on the performance of a reference water-cooled RCCS, the scaling analysis presented here needs to be 'validated' by analysis of the steady state and transient performance of a reference water-cooled RCCS design. The analysis of the RCCS performance by CFD and system codes presents a number of challenges including: strong 3-D effects in the cavity and the RCCS tubes; simulation of turbulence in flows characterized by natural circulation, high Rayleigh numbers and low Reynolds numbers; validity of heat transfer correlations for system codes for heat transfer in the cavity and the annulus of the RCCS tubes; the potential of nucleate boiling in the tubes; water flashing in the upper section of the RCCS return line (during limiting transient); and two-phase flow phenomena in the water tanks. The limited simulation of heat transfer in cavities presented in Section 4.0, strongly underscores the need of experimental work to validate CFD codes, and heat transfer correlations for system codes, and to support the analysis and design of the RCCS. Based on the conclusions of the scaling analysis, a schematic that illustrates key attributes of the experiment system is shown in Fig. 4. This system contains the same physical elements as the PBMR RCCS, plus additional equipment to facilitate data gathering to support code validation. In particular, the prototype consists of a series of oval standpipes surrounding the reactor vessel to provide cooling of the reactor cavity during both normal and off-normal operating conditions. The standpipes are headered (in groups of four in the prototype) to water supply (header) tanks that are situated well above the reactor vessel to facilitate natural convection cooling during a loss of forced flow event. During normal operations, the water is pumped from a heat sink located outside the containment to the headered inlets to the standpipes. The water is then delivered to each standpipe through a centrally located downcomer that passes the coolant to the bottom of each pipe. The water then turns 180{sup o} and rises up through the annular gap while extracting heat from the reactor cavity due to a combination of natural convection and radiation across the gap between the reactor vessel and standpipes. The water exits the standpipes at the top where it is headered (again in groups of four) into a return line that passes the coolant to the top of the header tank. Coolant is drawn from each tank through a fitting located near the top of the tank where it flows to the heat rejection system located outside the containment. This completes the flow circuit for normal operations. During off-normal conditions, forced convection water cooling in the RCCS is presumed to be lost, as well as the ultimate heat sink outside the containment. In this case, water is passively drawn from an open line located at the bottom of the header tank. This line is orificed so that flow bypass during normal operations is small, yet the line is large enough to provide adequate flow during passive operations to remove decay heat while maintaining acceptable fuel temperatures. In the passive operating mode, water flows by natural convection from the bottom of the supply tank to the standpipes, and returns through the normal pathway to the top of the tanks. After the water reaches saturation and boiling commences, steam will pass through the top of the tanks and be vented to atmosphere. In the experiment system shown in Fig. 4, a steam condensation and collection system is included to quantify the boiling rate, thereby providing additional validation data. This sys

Tzanos, C.P.; Farmer, M.T.; Nuclear Engineering Division

2007-08-31

152

MEDIUM POWER 352 MHZ SOLID STATE PULSED RF AMPLIFIERS FOR THE CERN LINAC4 PROJECT  

E-print Network

MEDIUM POWER 352 MHZ SOLID STATE PULSED RF AMPLIFIERS FOR THE CERN LINAC4 PROJECT J. Broere, J linear pulsed RF amplifiers have recently been developed to be used for the three buncher cavities in the CERN Linac4. The amplifiers are water-cooled and can provide up to 33 kW pulsed RF Power, 1.5 ms pulse

Paris-Sud XI, Université de

153

Programme A. Nuclear Power Subprogramme A.4 Technology Development for Advanced Reactor Lines  

E-print Network

Programme A. Nuclear Power Subprogramme A.4 Technology Development for Advanced Reactor Lines Cycle and Materials Technologies Subprogramme B.2 Nuclear Power Reactor Fuel Engineering Project B.2 Project A.4.01: Technology advances in water cooled reactors for improvements in economics and safety CRP

De Cindio, Fiorella

154

An Integrated View on Plasma Power Exhaust and In-vessel Components  

E-print Network

kinetic energy and electromagnetic waves. In addition control power will be injected in the plasma core divertor plates able to remove 10 MW/m2 have been produced (ITER water cooled) or are under developmentAn Integrated View on Plasma Power Exhaust and In-vessel Components 20% of the energy produced

155

Transient performance investigation of a space power system heat pipe  

Microsoft Academic Search

Start-up, shut-down, and peak power tests have been conducted with a molybdenum-lithium heat pipe at temperatures to 1500 K. The heat pipe was radiation coupled to a water-cooled calorimeter for the tests with RF induction heating used for the input to the evaporator region. Maximum power throughout in the tests was 36.8 kW corresponding to a power density of 23

M. A. Merrigan; E. S. Keddy; J. T. Sena

1986-01-01

156

Achievements in the development of the Water Cooled Solid Breeder Test Blanket Module of Japan to the milestones for installation in ITER  

NASA Astrophysics Data System (ADS)

As the primary candidate of ITER Test Blanket Module (TBM) to be tested under the leadership of Japan, a water cooled solid breeder (WCSB) TBM is being developed. This paper shows the recent achievements towards the milestones of ITER TBMs prior to the installation, which consist of design integration in ITER, module qualification and safety assessment. With respect to the design integration, targeting the detailed design final report in 2012, structure designs of the WCSB TBM and the interfacing components (common frame and backside shielding) that are placed in a test port of ITER and the layout of the cooling system are presented. As for the module qualification, a real-scale first wall mock-up fabricated by using the hot isostatic pressing method by structural material of reduced activation martensitic ferritic steel, F82H, and flow and irradiation test of the mock-up are presented. As for safety milestones, the contents of the preliminary safety report in 2008 consisting of source term identification, failure mode and effect analysis (FMEA) and identification of postulated initiating events (PIEs) and safety analyses are presented.

Tsuru, Daigo; Tanigawa, Hisashi; Hirose, Takanori; Mohri, Kensuke; Seki, Yohji; Enoeda, Mikio; Ezato, Koichiro; Suzuki, Satoshi; Nishi, Hiroshi; Akiba, Masato

2009-06-01

157

THE THERMAL AND HYDRAULIC CHARACTERISTICS OF POWER REACTOR FUEL BUNDLE DESIGNS  

Microsoft Academic Search

The type of fuel bundle evolved for the various Canadian heavy water-; moderated power reactors is described. The data necessary for estimating the ; thermal and hydraulic characteristics of this type of fuel bundle are indicated. ; The calculations and experimentation undertaken in the general fields of fluid ; flow, heat transfer, and coolant mixing are then described. The future

G. T. Leaist; R. D. Page; R. J. Klock

1963-01-01

158

Pump Characteristic based optimization of a direct water cooling system for a 10kW\\/500kHz Vienna rectifier  

Microsoft Academic Search

An ultra high power density 10-kW\\/500-kHz three-phase pulse-width modulation rectifier (Vienna Rectifier) is under development at the Power Electronic Systems Laboratory, ETH Zurich. From preliminary measurements and numerical simulations the total efficiency is assumed to be 95% at full load, resulting in power losses of up to 150 W in each multichip power module that realizes a bridge leg of

Uwe Drofenik; Gerold Laimer; Johann W. Kolar

2005-01-01

159

High voltage solar cell power generating system  

NASA Technical Reports Server (NTRS)

A laboratory solar power system regulated by on-panel switches has been delivered for operating high power (3 kW), high voltage (15,000 volt) loads (communication tubes, ion thrusters). The modular system consists of 26 solar arrays, each with an integral light source and cooling system. A typical array contains 2,560 series-connected cells. Each light source consists of twenty 500-watt tungsten iodide lamps providing plus or minus 5 percent uniformity at one solar constant. An array temperature of less than 40 C is achieved using an infrared filter, a water-cooled plate, a vacuum hold-down system, and air flushing.

Levy, E., Jr.; Opjorden, R. W.; Hoffman, A. C.

1974-01-01

160

20 kW water-cooled prototype of a buck-boost bidirectional DC-DC converter topology for electrical vehicle motor drives  

Microsoft Academic Search

In brushless DC motor drives devoted to electric vehicles (EVs) a bi-directional DC-DC power converter can be used to control suitably both motoring and regenerative braking operations in order to improve the motor drive performance. In consideration of such an application, this paper deals with the experimental study of a buck-boost bi-directional DC-DC power converter topology which has been conceived

F. Caricchi; F. Crescimbini; A. Di Napoli

1995-01-01

161

Thrust stand for high-power electric propulsion devices  

NASA Technical Reports Server (NTRS)

This paper describes a new high-power thrust stand developed for use with high-power (up to 250 kW) magnetoplasmadynamic (MPD) thrusters, which is installed in a high-vacuum MPD facility at Lewis Research Center. The design of the stand is based on inverted pendulum configuration, with the result of large displacements and high resolution. Calibration results showed that thrust measurements were linear and repeatable to within a fraction of 1 percent. The thrust stand was used for testing water-cooled MPD thrusters at power levels up to 125 kW. The thruster, however, is quite well suited for testing other types of electric propulsion devices.

Haag, T. W.

1991-01-01

162

High power radio frequency attenuation device  

DOEpatents

A resistor device for attenuating radio frequency power includes a radio frequency conductor connected to a series of fins formed of high relative magnetic permeability material. The fins are dimensional to accommodate the skin depth of the current conduction therethrough, as well as an inner heat conducting portion where current does not travel. Thermal connections for air or water cooling are provided for the inner heat conducting portions of each fin. Also disclosed is a resistor device to selectively alternate unwanted radio frequency energy in a resonant cavity.

Kerns, Quentin A. (Bloomingdale, IL); Miller, Harold W. (Winfield, IL)

1984-01-01

163

Thermodynamic Analysis of the Use a Chemical Heat Pump to Link a Supercritical Water-Cooled Nuclear Reactor and a Thermochemical Water-Splitting Cycle for Hydrogen Production  

NASA Astrophysics Data System (ADS)

Increases in the power generation efficiency of nuclear power plants (NPPs) are mainly limited by the permissible temperatures in nuclear reactors and the corresponding temperatures and pressures of the coolants in reactors. Coolant parameters are limited by the corrosion rates of materials and nuclear-reactor safety constraints. The advanced construction materials for the next generation of CANDU reactors, which employ supercritical water (SCW) as a coolant and heat carrier, permit improved steam parameters (outlet temperatures up to 625C and pressures of about 25 MPa). An increase in the temperature of steam allows it to be utilized in thermochemical water splitting cycles to produce hydrogen. These methods are considered by many to be among the most efficient ways to produce hydrogen from water and to have advantages over traditional low-temperature water electrolysis. However, even lower temperature water splitting cycles (Cu-Cl, UT-3, etc.) require an intensive heat supply at temperatures higher than 550-600C. A sufficient increase in the heat transfer from the nuclear reactor to a thermochemical water splitting cycle, without jeopardizing nuclear reactor safety, might be effectively achieved by application of a heat pump, which increases the temperature of the heat supplied by virtue of a cyclic process driven by mechanical or electrical work. Here, a high-temperature chemical heat pump, which employs the reversible catalytic methane conversion reaction, is proposed. The reaction shift from exothermic to endothermic and back is achieved by a change of the steam concentration in the reaction mixture. This heat pump, coupled with the second steam cycle of a SCW nuclear power generation plant on one side and a thermochemical water splitting cycle on the other, increases the temperature of the nuclear heat and, consequently, the intensity of heat transfer into the water splitting cycle. A comparative preliminary thermodynamic analysis is conducted of the combined system comprising a SCW nuclear power generation plant and a chemical heat pump, which provides high-temperature heat to a thermochemical water splitting cycle for hydrogen production. It is concluded that the proposed chemical heat pump permits the utilization efficiency of nuclear energy to be improved by at least 2% without jeopardizing nuclear reactor safety. Based on this analysis, further research appears to be merited on the proposed advanced design of a nuclear power generation plant combined with a chemical heat pump, and implementation in appropriate applications seems worthwhile.

Granovskii, Mikhail; Dincer, Ibrahim; Rosen, Marc A.; Pioro, Igor

164

Water cooling of HVDC thyristor valves  

Microsoft Academic Search

It is generally accepted that water is a very effective medium to remove heat losses from any type of equipment. When used for HVDC thyristor valves, the fundamentals of electrolyte conduction and water chemistry need to be considered in the design of the cooling circuit. The characteristics of the materials used, in conjunction with high voltage stresses and circuit configuration,

H. P. Lips

1994-01-01

165

Microchannel water cooling for LTCC based microsystems  

Microsoft Academic Search

The heat dissipation of six different types of microchannel networks integrated in LTCC based microsystems has been investigated by experimental measurement and simulation analysis, including straight, serpentine, spiral and fractal-shaped microchannel networks of curve, I-shaped and parallel. The cross section of microchannel is 200 m ?? 200 m and the total length is about 200 mm. The water mass flow

Yang-Fei Zhang; Jia-Qi Chen; Shu-Lin Bai; Yu-Feng Jin; Min Miao; Jing Zhang

2009-01-01

166

Biofilm formation in water cooling systems  

Microsoft Academic Search

Biofilm formation on stainless steel samples immersed in cooling water has been evaluated by exposing metal samples to cooling seawater for 30 days. Anaerobic bacteria were then at 1.6 106\\/cm2, with sulphate-reducing species predominating. Aerobic bacteria and fungi were 2600 and 140\\/cm2, respectively. After 60 days, numbers of aerobic microorganisms remained constant whereas the count of anaerobic microorganisms had

M. T. S. Lutterbach; F. P. Frana

1996-01-01

167

Diamond cooling of high power diode pumped solid state lasers  

NASA Astrophysics Data System (ADS)

We have demonstrated the feasibility of cooling high power solid-stae lasers with diamond windows, whose thermal conductivity is about two orders of magnitude higher than sapphire's. An output power of 200Watt was achieved froma single Nd:YVO4 slab in a zigzag configuration when pumped with 600Watt diodes at 808nm. The maximum output power reported in the literature with conventional cooling schemes is about 50W. A 2.3x4x24mm3 slab was pumped from its broad side (4x24 mm2) through a 0.3mm thick optical diamond window placed in close contact with the lasing crystal. The diamond window, held in a water-cooled copper housing acted as a heat conductor. The other broad side of the crystal was cooled directly by its water-cooled copper housing. Since pumping and cooling were along the same axis, a Cartesian thermal gradient was achieved, while the zigzag scheme was used to minimize thermal lensing. By using a BBO Q-switch, 70Watt average power was obtained at 20kHz with a pulse width of 19msec and with a beam quality of 3 and 12 times diffraction limit in the zigzag and transverse directions respectively. The output of a two-head configuration was 295Watt.

Tzuk, Yitshak; Tal, Alon; Goldring, Sharone; Glick, Yaakov; Lebiush, Eyal; Kaufman, Guy; Lavi, Raphael

2003-06-01

168

High-power radio-frequency attenuation device  

DOEpatents

A resistor device for attenuating radio frequency power includes a radio frequency conductor connected to a series of fins formed of high relative magnetic permeability material. The fins are dimensional to accommodate the skin depth of the current conduction therethrough, as well as an inner heat conducting portion where current does not travel. Thermal connections for air or water cooling are provided for the inner heat conducting portions of each fin. Also disclosed is a resistor device to selectively alternate unwanted radio frequency energy in a resonant cavity.

Kerns, Q.A.; Miller, H.W.

1981-12-30

169

New Concepts For High Power ICRF Antennas  

SciTech Connect

This paper presents new concepts for Ion Cyclotron Heating antennas based on cascaded sequences of tuned radiating structures. It is shown that, in large arrays, such as the ones proposed for fusion reactors applications, these schemes offer, in principle, a number of desirable features, such as operation at power density significantly higher than currently adopted systems, at equal maximum voltage and array geometry, simple mechanical layout, suitable for water cooling, a compact impedance tuning system, passive decoupling of the array elements, single ended or balanced feed from two power sources. The antenna layout also allows the remote, real time measurement of the complex impedance of the radiating elements and the detection, location, and measurement of the complex admittance of arcs occurring anywhere in the structure, as discussed in [1].

Bosia, G. [Department of Physics University of Turin (Italy)

2011-12-23

170

Water-Moderated and -Reflected Slabs of Uranium Oxyfluoride  

SciTech Connect

A series of ten experiments were conducted at the Oak Ridge National Laboratory Critical Experiment Facility in December 1955, and January 1956, in an attempt to determine critical conditions for a slab of aqueous uranium oxyfluoride (UO2F2). These experiments were recorded in an Oak Ridge Critical Experiments Logbook and results were published in a journal of the American Nuclear Society, Nuclear Science and Engineering, by J. K. Fox, L. W. Gilley, and J. H. Marable (Reference 1). The purpose of these experiments was to obtain the minimum critical thickness of an effectively infinite slab of UO2F2 solution by extrapolation of experimental data. To do this the slab thickness was varied and critical solution and water-reflector heights were measured using two different fuel solutions. Of the ten conducted experiments eight of the experiments reached critical conditions but the results of only six of the experiments were published in Reference 1. All ten experiments were evaluated from which five critical configurations were judged as acceptable criticality safety benchmarks. The total uncertainty in the acceptable benchmarks is between 0.25 and 0.33 % ?k/keff. UO2F2 fuel is also evaluated in HEU-SOL-THERM-043, HEU-SOL-THERM-011, and HEU-SOL-THERM-012, but these those evaluation reports are for large reflected and unreflected spheres. Aluminum cylinders of UO2F2 are evaluated in HEU-SOL-THERM-050.

Margaret A. Marshall; John D. Bess; J. Blair Briggs; Clinton Gross

2010-09-01

171

High voltage solar cell power generating system for regulated solar array development  

NASA Technical Reports Server (NTRS)

A laboratory solar power system regulated by on-panel switches has been delivered for operating high power (3 kw), high voltage (15,000 volt) loads (communication tubes, ion thrusters). The modular system consists of 26 solar arrays, each with an integral light source and cooling system. A typical array contains 2560 series-connected cells. Each light source consists of twenty 500 watt tungsten iodide lamps providing plus or minus 5 per cent uniformity at one solar constant. An array temperature of less than 40 C is achieved using an infrared filter, a water cooled plate, a vacuum hold-down system, and air flushing.

Levy, E., Jr.; Hoffman, A. C.

1973-01-01

172

Thermal testing of a high powered communications satellite  

NASA Technical Reports Server (NTRS)

Thermal Vacuum and Thermal Balance tests were successfully conducted on the high power Communications Technology Satellite (CTS). The mission required testing for two distinct thermal environments; spin stabilized at 60 rpm with a minimum of 55 watts of dissipated power, and three-axis stabilized with as much as a tenfold increase of dissipation. The test program verified the adequacy of the spacecraft thermal design and demonstrated functional operation over a wide temperature range for all of the components. Special test hardware incorporating water-cooling systems was required to accomodate the heatpipes and high RF output power. Objectives, test facilities, special hardware, spacecraft configurations, and results of the tests are discussed. Preliminary flight results and conclusions drawn from the test experience are reported.

Caswell, R. D.; Edelman, E. A.

1976-01-01

173

Evolution of the core physics concept for the Canadian supercritical water reactor  

SciTech Connect

The supercritical water cooled reactor (SCWR) is one of the advanced reactor concepts chosen by the GEN-IV International Forum (GIF) for research and development efforts. Canada's contribution is the Canadian SCWR, a heavy water moderated, pressure tube supercritical light water cooled reactor. Recent developments in the SCWR lattice and core concepts, primarily the introduction of a large central flow tube filled with coolant combined with a two-ring fuel assembly, have enabled significant improvements compared to earlier concepts. These improvements include a reduction in coolant void reactivity (CVR) by more than 10 mk, and an almost 40% increase in fuel exit burnup, which is achieved via balanced power distribution between the fuel pins in the fuel assembly. In this paper the evolution of the physics concept is reviewed, and the present lattice and core physics concepts are presented.

Pencer, J.; Colton, A.; Wang, X.; Gaudet, M.; Hamilton, H.; Yetisir, M. [Atomic Energy of Canada, Ltd., Chalk River Laboratories, Chalk River, ON (Canada)

2013-07-01

174

A novel power block for CSP systems  

SciTech Connect

Concentrating Solar Thermal Power (CSP) and in particular parabolic trough, is a proven large-scale solar power technology. However, CSP cost is not yet competitive with conventional alternatives unless subsidized. Current CSP plants typically include a condensing steam cycle power block which was preferably designed for a continuous operation and higher operating conditions and therefore, limits the overall plant cost effectiveness and deployment. The drawbacks of this power block are as follows: (i) no power generation during low insolation periods (ii) expensive, large condenser (typically water cooled) due to the poor extracted steam properties (high specific volume, sub-atmospheric pressure) and (iii) high installation and operation costs. In the current study, a different power block scheme is proposed to eliminate these obstacles. This power block includes a top Rankine cycle with a back pressure steam turbine and a bottoming Kalina cycle comprising another back pressure turbine and using ammonia-water mixture as a working fluid. The bottoming (moderate temperature) cycle allows power production during low insolation periods. Because of the superior ammonia-water vapor properties, the condensing system requirements are much less demanding and the operation costs are lowered. Accordingly, air cooled condensers can be used with lower economical penalty. Another advantage is that back pressure steam turbines have a less complex design than condensing steam turbines which make their costs lower. All of these improvements could make the combined cycle unit more cost effective. This unit can be applicable in both parabolic trough and central receiver (solar tower) plants. The potential advantage of the new power block is illustrated by a detailed techno-economical analysis of two 50 MW parabolic trough power plants, comparing between the standard and the novel power block. The results indicate that the proposed plant suggests a 4-11% electricity cost saving. (author)

Mittelman, Gur [ASP Ltd., Advanced Solar Power, Industrial Zone, Be'er Tuviyya (Israel); Epstein, Michael [Solar Research Facilities Unit, Weizmann Institute of Science (Israel)

2010-10-15

175

Small-Scale Geothermal Power Plant Field Verification Projects: Preprint  

SciTech Connect

In the spring of 2000, the National Renewable Energy Laboratory issued a Request for Proposal for the construction of small-scale (300 kilowatt [kW] to 1 megawatt [MW]) geothermal power plants in the western United States. Five projects were selected for funding. Of these five, subcontracts have been completed for three, and preliminary design work is being conducted. The three projects currently under contract represent a variety of concepts and locations: a 1-MW evaporatively enhanced, air-cooled binary-cycle plant in Nevada; a 1-MW water-cooled Kalina-cycle plant in New Mexico; and a 750-kW low-temperature flash plant in Utah. All three also incorporate direct heating: onion dehydration, heating for a fish hatchery, and greenhouse heating, respectively. These projects are expected to begin operation between April 2002 and September 2003. In each case, detailed data on performance and costs will be taken over a 3-year period.

Kutscher, C.

2001-07-03

176

A Solar Thermophotovoltaic Electric Generator for Remote Power Applications  

NASA Technical Reports Server (NTRS)

We have successfully demonstrated that a solar thermophotovoltaic (TPV) system with a SiC graybody emitter and the monolithic interconnected module device technology can be realized. A custom-designed solar cavity was made to house the SiC emitter and the MIM strings for testing in a Stirling dish solar concentrator. Five 1x1-cm MIMs, with a bandgap of 0.74 eV,were mounted on a specially designed water-cooled heatsink and were electrically connected in series to form a string. Two such strings were fabricated and tested, as well as high-performance 2x2-cm MIMs with a bandgap of 0.74 eV. Very high output power density values between 0.82 and 0.90 W/sq cm were observed for an average emitter temperature of 1501 K.

Fatemi, Navid S.

1998-01-01

177

A Solar Thermophotovoltaic Electric Generator for Remote Power Applications  

NASA Technical Reports Server (NTRS)

We have successfully demonstrated that a solar thermophotovoltaic (TPV) system with a SiC graybody emitter and the monolithic interconnected module device technology can be realized. A custom-designed solar cavity was made to house the SiC emitter and the Monolithic Integrated Module (MIM) strings for testing in a Stirling dish solar concentrator. Five 1x1-cm MIMs, with a bandgap of 0.74 eV, were mounted on a specially designed water-cooled heatsink and were electrically connected in series to form a string. Two such strings were fabricated and tested, as well as high-performance 2x2-cm MIMs with a bandgap of 0.74 eV. Very high output power density values between 0.82 and 0.90 W/ square cm were observed for an average emitter temperature of 1501 K.

Fatemi, Navid S.

1998-01-01

178

STARFIRE: a commercial tokamak fusion power plant study  

SciTech Connect

STARFIRE is a 1200 MWe central station fusion electric power plant that utilizes a deuterium-tritium fueled tokamak reactor as a heat source. Emphasis has been placed on developing design features which will provide for simpler assembly and maintenance, and improved safety and environmental characteristics. The major features of STARFIRE include a steady-state operating mode based on continuous rf lower-hybrid current drive and auxiliary heating, solid tritium breeder material, pressurized water cooling, limiter/vacuum system for impurity control and exhaust, high tritium burnup and low vulnerable tritium inventories, superconducting EF coils outside the superconducting TF coils, fully remote maintenance, and a low-activation shield. A comprehensive conceptual design has been developed including reactor features, support facilities and a complete balance of plant. A construction schedule and cost estimate are presented, as well as study conclusions and recommendations.

Not Available

1980-09-01

179

Medium Power 352 MHZ solid state pulsed RF amplifiers for the CERN LINAC4 Project  

E-print Network

Economic, modular and highly linear pulsed RF amplifiers have recently been developed to be used for the three buncher cavities in the CERN Linac4. The amplifiers are water-cooled and can provide up to 33 kW pulsed RF Power, 1.5 ms pulse length and 50 Hz repetition rate. Furthermore a 60 kW unit is under construction to provide the required RF Power for the debuncher cavity. The concept is based on 1.2 kW RF power modules using the latest 6th generation LDMOS technology. For integration into the CERN control environment the amplifiers have an internal industrial controller, which will provide easy control and extended diagnostic functions. This paper describes the construction, performance, including linearity, phase stability and EMC compliance tests

Broere, J; Gmez Martnez, Y; Rossi, M

2011-01-01

180

Power Plant Power Plant  

E-print Network

Basin Center for Geothermal Energy at University of Nevada, Reno (UNR) 2 Nevada Geodetic LaboratoryStillwater Power Plant Wabuska Power Plant Casa Diablo Power Plant Glass Mountain Geothermal Area Lassen Geothermal Area Coso Hot Springs Power Plants Lake City Geothermal Area Thermo Geothermal Area

Tingley, Joseph V.

181

Formation of a nuclear reactor's molten core bath in a crucible-type corium catcher for a nuclear power station equipped with VVER reactors  

NASA Astrophysics Data System (ADS)

Results from a calculation study on analyzing the formation of a melt bath in a crucible-type catcher for the conditions of a severe accident at a nuclear power station equipped with VVER-1000 reactors are presented. It is shown that the heat loads exerted on the water-cooled walls of the corium catcher shell are limited to a permissible level at which the necessary margins to nucleate boiling crisis and to destruction are ensured under the conditions of thermal and mechanical loading of the shell. An important role of sacrificial material in the efficient operation of the corium catcher is pointed out.

Beshta, S. V.; Vitol', S. A.; Granovskii, V. S.; Kalyago, E. K.; Kovtunova, S. V.; Krushinov, E. V.; Sulatskaya, M. B.; Sulatskii, A. A.; Khabenskii, V. B.; Al'Myashev, V. I.; Gusarov, V. V.

2011-05-01

182

Robust focusing optics for high-power laser welding  

NASA Astrophysics Data System (ADS)

As available power levels from both fiber and disc lasers rapidly increase, so does the need for more robust beam delivery solutions. Traditional transmissive optics for 1 micron lasers have proven to be problematic in the presence of higher power densities and are more susceptible to focal shift. A new, fully-reflective, optical solution has been developed using mirrors rather than lenses and windows to achieve the required stable focal spot, while still protecting the delicate fiber end. This patent-approved beam focusing solution, referred to as high power reflective focusing optic (HPRFO), involves specialty mirrors and a flowing gas orifice that prevents ingress of contaminants into the optically sensitive region of the assembly. These mirrors also provide a unique solution for increasing the distance between the sensitive optics and the contamination-filled region at the work, without sacrificing spot size. Longer focal lengths and lower power densities on large mass, water-cooled, copper mirrors deliver the robustness needed at increasingly high power levels. The HPRFO exhibits excellent beam quality and minimal focal shift at a fraction of commercially available optics, and has demonstrated consistent reliability on applications requiring 15 kW with prolonged beam-on times.

McAllister, Blake

2014-02-01

183

Physical model and experimental results of cathode erosion related to power supply ripple  

NASA Technical Reports Server (NTRS)

This paper discusses the physical effects of power supply ripple on cathode erosion and cathode arc attachment in a water-cooled, 30 kW nitrogen arcjet. Experimental results are presented for 2 percent thoriated tungsten, which show that the long-term cathode erosion rate is a decreasing function of current ripple over the range 1-13 percent. Above this range, the cathode discharge becomes unstable, and the erosion rate rapidly increases. A qualitative model of this effect is given in terms of a magnetically induced radial motion of the arc column, and an overall increase in the cathode spot radius due to the higher peak current associated with higher ripple. The most important effect of power supply ripple is therefore shown to be its ability to collectively drive the cathode attachment away from the cathode center. This leads to an increase in the cathode attachment area, and a subsequent decrease in the cathode erosion rate.

Harris, W. J.; O'Hair, E. A.; Hatfield, L. L.; Kristiansen, M.

1992-01-01

184

Natural gas powered rotary water chiller development. Phase 1. Final report, September 1991-June 1993  

SciTech Connect

Objectives of the project were to evaluate performance and marketability of a rotary engine driven screw compressor for water chiller applications. Choice of a rotary engine was aimed at rotary compressor. Initial testing done with modified stock 13B rotary engine and experimental open compressor. Engine torque not sufficient for 70 ton compressor. Analysis concluded 50 ton best match for air cooled applications and 60 ton best for water cooled to get highest gas COP. Market analysis covered total water chiller market assuming relative costs of power would lead to gas cooling sales. Allowable cost premium for 3 yr payback determined for areas of country. Premium cost of 100 ton air cooled unit estimated and compared to market allowable premiums. Concluded product acceptance will be primarily in niche markets with high local electric power demand charges.

Sanborn, D.F.; Lakowske, R.L.; Byars, M.

1993-06-01

185

Transient performance investigation of a space power system heat pipe  

SciTech Connect

Start-up, shut-down, and peak power tests have been conducted with a molybdenum-lithium heat pipe at temperatures to 1500 K. The heat pipe was radiation coupled to a water cooled calorimeter for the tests with rf induction heating used for the input to the evaporator region. Maximum power throughput in the tests was 36.8 kw corresponding to a power density of 23 kw/cm/sup 2/ for the 1.4 cm diameter vapor space of the annular wick heat pipe. The corresponding evaporator flux density was approximately 150 w/cm/sup 2/ over an evaporator length of 40 cm at peak power. Condenser length for the tests was approximately 3.0 m. A variable geometry radiation shield was used to vary the load on the heat pipe during the tests. Results of the tests showed that liquid depletion in the evaporator region of the heat pipe could occur in shut-down and prevent restart of the heat pipe. Changes in surface emissivity of the heat pipe condenser surface were shown to affect the shut-down and re-start limits. 12 figs.

Merrigan, M.A.; Keddy, E.S.; Sena, J.T.

1986-01-01

186

Anode arc motion in high power arcjets  

NASA Technical Reports Server (NTRS)

The long-term operational lifetime of most medium to high power arcjets is currently limited by the rapid deterioration of the arcjet electrodes. To a large extent, the rate of this deterioration is related to the motion of the arc discharge on the electrode surfaces. This paper details a series of experiments aimed at studying the temporal behavior of dc arcs on a water-cooled radially-segmented 30 kW class arcjet anode. The experimental anode used for these tests was made of copper, and was divided into four equivalent radial segments which were electrically isolated with aluminum oxide gaskets. The current carried by each segment was measured independently using four calibrated resistive shunts, and was analyzed by digital computer. The tests were limited to nitrogen propellant over a current range of 100-250 A dc. Results show that for the range of total currents considered here, the current distribution in the segmented arcjet anode is generally asymmetric, exhibiting random fluctuations over a wide range of frequencies.

Harris, W. J.; O'Hair, E. A.; Hatfield, L. L.; Kristiansen, M.; Mankins, J. S.

1992-01-01

187

Heat Recovery From Arc Furnaces Using Water Cooled Panels  

E-print Network

, deter ioration, and erosion. Heavy wall seamless steel pipe is cast into each panel to form the water passages. This de sign provides 7 inch thick sections of cast iron that resist damage even when heavy scrap is charged into the furnace. Cooling... exchanger HE-l whose secondary side is connected to the heat/vent units via the glycol distribution piping. The primary water than passes through a water to water heat exchanger HE-2 (whose secondary side is connected to the cooling tower CT...

Darby, D. F.

188

PRECIPITATION-HARDENING STAINLESS STEELS IN WATER-COOLED REACTORS  

Microsoft Academic Search

A study is made of the stress corrosion susceptibiity of unirradiated ; precipitation-hardening stainless steels. This study is made because of the ; failures encouatered with these materials in the Dresden and Vallecltos boiling ; water reactors. Service experience, static steam autoclave tests, and dynamic ; water and steam corrosion loop tests have demonstrated that 17-4 PH in the high-;

M. C. Rowland; W. R. Sr. Smith

1962-01-01

189

Low-pressure water-cooled inductively coupled plasma torch  

DOEpatents

An inductively coupled plasma torch is provided which comprises an inner tube, including a sample injection port to which the sample to be tested is supplied and comprising an enlarged central portion in which the plasma flame is confined; an outer tube surrounding the inner tube and containing water therein for cooling the inner tube, the outer tube including a water inlet port to which water is supplied and a water outlet port spaced from the water inlet port and from which water is removed after flowing through the outer tube; and an rf induction coil for inducing the plasma in the gas passing into the tube through the sample injection port. The sample injection port comprises a capillary tube including a reduced diameter orifice, projecting into the lower end of the inner tube. The water inlet is located at the lower end of the outer tube and the rf heating coil is disposed around the outer tube above and adjacent to the water inlet.

Seliskar, C.J.; Warner, D.K.

1984-02-16

190

Low-pressure water-cooled inductively coupled plasma torch  

DOEpatents

An inductively coupled plasma torch is provided which comprises an inner tube, including a sample injection port to which the sample to be tested is supplied and comprising an enlarged central portion in which the plasma flame is confined; an outer tube surrounding the inner tube and containing water therein for cooling the inner tube, the outer tube including a water inlet port to which water is supplied and a water outlet port spaced from the water inlet port and from which water is removed after flowing through the outer tube; and an r.f. induction coil for inducing the plasma in the gas passing into the tube through the sample injection port. The sample injection port comprises a capillary tube including a reduced diameter orifice, projecting into the lower end of the inner tube. The water inlet is located at the lower end of the outer tube and the r.f. heating coil is disposed around the outer tube above and adjacent to the water inlet.

Seliskar, Carl J. (Cincinnati, OH); Warner, David K. (Centerville, OH)

1988-12-27

191

North Atlantic Deep Water cools the southern hemisphere  

NASA Astrophysics Data System (ADS)

A standard explanation for coupling climate variations in the northern and southern hemispheres involves fluctuations in North Atlantic Deep Water (NADW) production. However, I suggest that the "NADW-Antarctic" connection may work opposite to that conjectured by many investigators; that is, when NADW production rates are high, southern hemisphere temperatures decrease rather than increase. The revised interpretation is consistent with observations and ocean modeling studies which demonstrate that, although upwelling of relatively warm NADW water around Antarctica promotes sea ice meltback, a second and more important negative feedback is also operating. In order to conserve volume, southward export of NADW across the equator is accompanied by import of an equivalent volume of considerably warmer water from shallower oceanic layers in the South Atlantic. The southern hemisphere loses heat as a result of this exchange. The hemispherically averaged net heat loss may be as high as 4 W/m, an amount comparable to a CO2 doubling. It is suggested that this more comprehensive view of the role of NADW may explain both decadal-scale variations in South Atlantic sea surface temperatures in this century and two significant problems in Pleistocene climatology: why southern hemisphere temperatures decreased before CO2 levels decreased at the end of the last interglacial and why southern hemisphere temperature changes precede changes in northern hemisphere ice volume. It is shown that when NADW production was reinitiated during the last interglacial (120,000 B.P.), high-latitude southern hemisphere temperatures decreased. The estimated magnitude of altered southern hemisphere heat export is comparable to the ice-age CO2 signal and may be able to account for the observed cooling even when CO2 levels were high. When cast into a frequency domain framework, this interpretation may also help explain why southern hemisphere temperatures lead global ice volume changes.

Crowley, Thomas J.

1992-08-01

192

High-power, low-pressure, inductively coupled RF plasma source using a FET-based inverter power supply  

NASA Astrophysics Data System (ADS)

A high-density plasma of density greater than 1019 m?3 is successfully produced in 1.5 Pa argon by an inductively coupled RF discharge with a 70-mm-diameter source cavity, where a 10-turn water-cooled RF loop antenna is wound onto the source tube and an axial magnetic field of ?70 G is applied by two solenoids to reduce plasma loss onto the source cavity. The RF antenna is powered from a frequency-tunable field-effect-transistor-based inverter power supply, which does not require variable capacitors to match the impedance, at a frequency of ?350 kHz and the RF power can be increased up to ?8 kW. It is also demonstrated that the source is operational with an axial magnetic field provided by permanent magnet (PM) arrays; then the density in the case of the PM arrays is higher than that in the case of the solenoids. The role of the magnetic filter downstream of the source tube is demonstrated; a radially uniform plasma density exceeding 1018 m?3 and an electron temperature of ?12 eV are obtained at ?100 mm downstream of the open exit of the source tube.

Komizunai, Shota; Oikawa, Kohei; Saito, Yuta; Takahashi, Kazunori; Ando, Akira

2015-01-01

193

Terbium gallium garnet ceramic Faraday rotator for high-power laser application.  

PubMed

A terbium gallium garnet (TGG) ceramic Faraday rotator (FR) with an isolation ratio of 33 dB was demonstrated at a laser radiation power of 257 W. This FR can be equipped with a large optical aperture by using ceramics technology to prevent laser damage at high-energy pulse operation. The thermal lens of a 257 W laser with a beam diameter of 2.6 mm had a focal length of 9.5 m, which is easily corrected using a spherical lens to suppress the undesirable effects of thermal lensing. The rotation angle of the FR was stabilized by water cooling. The results indicate that the TGG-ceramic-based FR is suitable for high-energy laser systems with high repetition rates. PMID:24690692

Yasuhara, Ryo; Snetkov, Ilya; Starobor, Alexey; Zheleznov, Dmitry; Palashov, Oleg; Khazanov, Efim; Nozawa, Hoshiteru; Yanagitani, Takagimi

2014-03-01

194

An experimental study of energy loss mechanisms and efficiency consideration in the low power dc arcjet  

NASA Technical Reports Server (NTRS)

The potential utility of the low power dc arcjet in auxiliary propulsion was investigated. It was indicated that improvements in the areas of stability, energy efficiency, reliability, and electrode erosion are necessary to obtain a useful device. A water-cooled arcjet simulator was tested to investigate both the energy loss mechanisms at the electrodes and the stability of different conventional arcjet configurations in the presence of a vortex flow field. It is shown that in certain configurations only 25 to 30% of the input energy is lost to the electrodes. It is also shown that vortex stabilization is not difficult to obtain in many cases at the flow rates used and that a careful starting procedure is effective in minimizing electrode damage.

Curran, F. M.

1985-01-01

195

An experimental study of energy loss mechanisms and efficiency considerations in the low power dc arcjet  

NASA Technical Reports Server (NTRS)

The potential utility of the low power dc arcjet in auxiliary propulsion was investigated. It was indicated that improvements in the areas of stability, energy efficiency, reliability, and electrode erosion are necessary to obtain a useful device. A water-cooled arcjet simulator was tested to investigate both the energy loss mechanisms at the electrodes and the stability of different conventional arcjet configurations in the presence of a vortex flow field. It is shown that in certain configurations only 25 to 30 percent of the input energy is lost to the electrodes. It is also shown that vortex stabilization is not difficult to obtain in many cases at the flow rates used and that a careful starting procedure is effective in minimizing electrode damage.

Curran, F. M.

1985-01-01

196

Terbium gallium garnet ceramic-based Faraday isolator with compensation of thermally induced depolarization for high-energy pulsed lasers with kilowatt average power  

NASA Astrophysics Data System (ADS)

A scalable aperture Faraday isolator for high-energy pulsed lasers with kW-level average power was demonstrated using terbium gallium garnet ceramics with water cooling and compensation of thermally induced depolarization in a magnetic field. An isolation ratio of 35 dB (depolarization ratio ? of 3.4 10-4) was experimentally observed at a maximum laser power of 740 W. By using this result, we estimated that this isolator maintains an isolation ratio of 30 dB for laser powers of up to 2.7 kW. Our results provide the solution for achieving optical isolation in high-energy (100 J to kJ) laser systems with a repetition rate greater than 10 Hz.

Yasuhara, Ryo; Snetkov, Ilya; Starobor, Alexey; Palashov, Oleg

2014-12-01

197

Numerical investigation of mass transfer in the flow path of the experimental model of the PGV-1500 steam generator's steam receiving section with two steam nozzles  

NASA Astrophysics Data System (ADS)

The hydrodynamics of working medium in the steam volume model implemented in the experimental setup constructed at the Leipunskii Institute for Physics and Power Engineering was simulated for verifying the procedure of calculating the velocity field in the steam space of steam generators used as part of the reactor plants constructed on the basis of water-cooled water-moderated power-generating reactors (VVER). The numerical calculation was implemented in the environment of the STAR-CCM+ software system with its cross verification in the STAR-CD and ANSYS CFX software systems. The performed numerical investigation served as a basis for substantiating the selection of the computation code and parameters for constructing the computer model of the steam receiving device of the PGV-1500 steam generator experimental model, such as the quantization scheme, turbulence model, and mesh model.

Golibrodo, L. A.; Krutikov, A. A.; Nadinskii, Yu. N.; Nikolaeva, A. V.; Skibin, A. P.; Sotskov, V. V.

2014-10-01

198

Powering Smallsburg  

NSDL National Science Digital Library

In this activity, students act as power engineers by specifying the power plants to build for a community. They are given a budget, an expected power demand from the community, and different power plant options with corresponding environmental effects. They can work through this scenario as a class or on their own.

Integrated Teaching And Learning Program

199

Design of compressor ratio power tester with condition protection function based on virtual instrument  

NASA Astrophysics Data System (ADS)

Ratio power is one of the important performance parameters of compressor. The paper researched the compressor automatic test technology based on Virtual Instrument and then designed a convenient and high efficiency compressor ratio power tester with additional condition protection function applied in industry field. In the paper, a test scheme with PXI bus hardware and LabVIEW software was proposed. Then, based on research of vibration signal process method, realization arithmetic of automatic computational parameters tables search and theory of wavelet packet frequency band divided energy, an intelligent ratio power tester was introduced in detail. The instrument can monitor compressor running condition before or in the process of testing the value of ratio power, obtain each relate tested parameter automatically and show change trend, compute values of multi-type compressor ratio powers with automatic tables search and also give the compressor performance estimate results. The testing field running results with a water-cooling two level compressor shows that the tester has exact and fast calculation and has virtues of high efficiency, reliable performance and convenient use.

Niu, Qunfeng; Wang, Lia; Huang, Junren

2008-12-01

200

Use of Cooling Thermal Storage as a Heat Sink for Steam Power Plant  

NASA Astrophysics Data System (ADS)

In the present paper, a system is proposed for improving the performance of steam power plant with air-cooled condenser during peak loads. In this system, the power plant comprises two steam turbines, and the air-cooled condenser is replaced by two condensers. The first one is air-cooled (dry) and used for condensing the exhaust steam of the first turbine, while the second is water-cooled and serves to condense the steam outlet of the second turbine. The warm cooling water exiting the wet condenser is pumped to a cooling storage container, where it is cooled and re-circulated to the wet condenser. Cooling is produced by a refrigeration machine driven by the extra electric power generated by the two turbines during the time of the off-peak-loads (low electricity rates). Simple energy analyses have been developed to predict the energy characteristics of this system. The results of this paper showed that the proposed system leads to improving the plant power output at peak-loads. About 6, 16, 24 and 33% increase in generated plant power can be achieved at peak-loads (high electricity rates) when the ambient temperature is 20, 30, 40 and 50C respectively, and the whole steam exiting both turbines is cooled in a wet condenser to a design temperature of 20C. The results showed also that choice of the capacity of each turbine is essentially affected by the quality of the refrigeration machine and ambient temperature.

Hegazy, Ahmed Sabry

201

Fission Surface Power Systems (FSPS) Project Final Report for the Exploration Technology Development Program (ETDP): Fission Surface Power, Transition Face to Face  

NASA Technical Reports Server (NTRS)

The Fission Surface Power Systems Project became part of the ETDP on October 1, 2008. Its goal was to demonstrate fission power system technology readiness in an operationally relevant environment, while providing data on fission system characteristics pertinent to the use of a fission power system on planetary surfaces. During fiscal years 08 to 10, the FSPS project activities were dominated by hardware demonstrations of component technologies, to verify their readiness for inclusion in the fission surface power system. These Pathfinders demonstrated multi-kWe Stirling power conversion operating with heat delivered via liquid metal NaK, composite Ti/H2O heat pipe radiator panel operations at 400 K input water temperature, no-moving-part electromagnetic liquid metal pump operation with NaK at flight-like temperatures, and subscale performance of an electric resistance reactor simulator capable of reproducing characteristics of a nuclear reactor for the purpose of system-level testing, and a longer list of component technologies included in the attached report. Based on the successful conclusion of Pathfinder testing, work began in 2010 on design and development of the Technology Demonstration Unit (TDU), a full-scale 1/4 power system-level non-nuclear assembly of a reactor simulator, power conversion, heat rejection, instrumentation and controls, and power management and distribution. The TDU will be developed and fabricated during fiscal years 11 and 12, culminating in initial testing with water cooling replacing the heat rejection system in 2012, and complete testing of the full TDU by the end of 2014. Due to its importance for Mars exploration, potential applicability to missions preceding Mars missions, and readiness for an early system-level demonstration, the Enabling Technology Development and Demonstration program is currently planning to continue the project as the Fission Power Systems project, including emphasis on the TDU completion and testing.

Palac, Donald T.

2011-01-01

202

Continuous improvement of high-efficiency high-power 800-980nm diode lasers at Spectra-Physics  

NASA Astrophysics Data System (ADS)

New-generation multi-mode 9xx mini-bars used in fiber pump modules have been developed. The epitaxial designs have been improved for lower fast-axis and slow-axis divergence, higher slope efficiency and PCE by optimizing layer structures as well as minimizing internal loss. For 915nm mini-bars with 5-mm cavity length, maximum PCE is as high as ~61% for 35W operation and remains above 59% at 45W. For 808nm, a PCE of 56% at 135W CW operation has been demonstrated with 36%-fill-factor, 3-mm-cavity-length, water-cooled bars at 50C coolant temperature. On passive-cooled standard CS heatsinks, PCE of >51% is measured for 100W operation at 50C heatsink temperature. Leveraging these improvements has enabled low-cost bars for high-power, high-temperature applications.

Li, Hanxuan; Towe, Terry; Chyr, Irving; Jin, Xu; Miller, Robert; Romero, Oscar; Liu, Daming; Brown, Denny; Truchan, Tom; Nguyen, Touyen; Crum, Trevor; Wolak, Ed; Bullock, Robert; Mott, Jeff; Harrison, James

2009-02-01

203

High Power Flex-Propellant Arcjet Performance  

NASA Technical Reports Server (NTRS)

A MW-class electrothermal arcjet based on a water-cooled, wall-stabilized, constricted arc discharge configuration was subjected to extensive performance testing using hydrogen and simulated ammonia propellants with the deliberate aim of advancing technology readiness level for potential space propulsion applications. The breadboard design incorporates alternating conductor/insulator wafers to form a discharge barrel enclosure with a 2.5-cm internal bore diameter and an overall length of approximately 1 meter. Swirling propellant flow is introduced into the barrel, and a DC arc discharge mode is established between a backplate tungsten cathode button and a downstream ringanode/ spin-coil assembly. The arc-heated propellant then enters a short mixing plenum and is accelerated through a converging-diverging graphite nozzle. This innovative design configuration differs substantially from conventional arcjet thrusters, in which the throat functions as constrictor and the expansion nozzle serves as the anode, and permits the attainment of an equilibrium sonic throat (EST) condition. During the test program, applied electrical input power was varied between 0.5-1 MW with hydrogen and simulated ammonia flow rates in the range of 4-12 g/s and 15-35 g/s, respectively. The ranges of investigated specific input energy therefore fell between 50-250 MJ/kg for hydrogen and 10-60 MJ/kg for ammonia. In both cases, observed arc efficiencies were between 40-60 percent as determined via a simple heat balance method based on electrical input power and coolant water calorimeter measurements. These experimental results were found to be in excellent agreement with theoretical chemical equilibrium predictions, thereby validating the EST assumption and enabling the utilization of standard TDK nozzle expansion analyses to reliably infer baseline thruster performance characteristics. Inferred specific impulse performance accounting for recombination kinetics during the expansion process implied nearly frozen flow in the nozzle and yielded performance ranges of 800-1100 sec for hydrogen and 400-600 sec for ammonia. Inferred thrust-to-power ratios were in the range of 30-10 lbf/MWe for hydrogen and 60-20 lbf/MWe for ammonia. Successful completion of this test series represents a fundamental milestone in the progression of high power arcjet technology, and it is hoped that the results may serve as a reliable touchstone for the future development of MW-class regeneratively-cooled flex-propellant plasma rockets.

Litchford, Ron J.

2011-01-01

204

From the first nuclear power plant to fourth-generation nuclear power installations [on the 60th anniversary of the World's First nuclear power plant  

NASA Astrophysics Data System (ADS)

Successful commissioning in the 1954 of the World's First nuclear power plant constructed at the Institute for Physics and Power Engineering (IPPE) in Obninsk signaled a turn from military programs to peaceful utilization of atomic energy. Up to the decommissioning of this plant, the AM reactor served as one of the main reactor bases on which neutron-physical investigations and investigations in solid state physics were carried out, fuel rods and electricity generating channels were tested, and isotope products were bred. The plant served as a center for training Soviet and foreign specialists on nuclear power plants, the personnel of the Lenin nuclear-powered icebreaker, and others. The IPPE development history is linked with the names of I.V. Kurchatov, A.I. Leipunskii, D.I. Blokhintsev, A.P. Aleksandrov, and E.P. Slavskii. More than 120 projects of various nuclear power installations were developed under the scientific leadership of the IPPE for submarine, terrestrial, and space applications, including two water-cooled power units at the Beloyarsk NPP in Ural, the Bilibino nuclear cogeneration station in Chukotka, crawler-mounted transportable TES-3 power station, the BN-350 reactor in Kazakhstan, and the BN-600 power unit at the Beloyarsk NPP. Owing to efforts taken on implementing the program for developing fast-neutron reactors, Russia occupied leading positions around the world in this field. All this time, IPPE specialists worked on elaborating the principles of energy supertechnologies of the 21st century. New large experimental installations have been put in operation, including the nuclear-laser setup B, the EGP-15 accelerator, the large physical setup BFS, the high-pressure setup SVD-2; scientific, engineering, and technological schools have been established in the field of high- and intermediate-energy nuclear physics, electrostatic accelerators of multicharge ions, plasma processes in thermionic converters and nuclear-pumped lasers, physics of compact nuclear reactors and radiation protection, thermal physics, physical chemistry and technology of liquid metal coolants, and physics of radiation-induced defects, and radiation materials science. The activity of the institute is aimed at solving matters concerned with technological development of large-scale nuclear power engineering on the basis of a closed nuclear fuel cycle with the use of fast-neutron reactors (referred to henceforth as fast reactors), development of innovative nuclear and conventional technologies, and extension of their application fields.

Rachkov, V. I.; Kalyakin, S. G.; Kukharchuk, O. F.; Orlov, Yu. I.; Sorokin, A. P.

2014-05-01

205

Closed-cycle gas turbines for power generation and LNG vaporization  

NASA Astrophysics Data System (ADS)

Cooling by LNG (liquefied nitrogen gas) in closed-cycle gas turbines results in double the electrical output of water cooled turbines. A circuit scheme of the LNG turbine is presented with the temperatures and pressures of the cycle. The turbine inlet temperature is limited to 720 C. Pressure level control and bypass control are the two basic types of control applied. The power station has an output of 4 x 100 MW, with four heaters arranged in series. The basic design of the heater, turbine, compressor, recuperator, and vaporizer is given. A cost comparison is made between the closed cycle gas turbine and steam turbine power stations with open rack vaporizer, submerged combustion vaporizer, or both. Using an LNG terminal with a closed-cycle gas turbine for the generation of electric power and LNG vaporization would mean a potential world-wide saving of 2,350 MW thermal power or 4.2 x 10(6) kg of LNG/day by 1985.

Weber, D.

1980-09-01

206

Space Power  

NASA Technical Reports Server (NTRS)

Appropriate directions for the applied research and technology programs that will develop space power systems for U.S. future space missions beyond 1995 are explored. Spacecraft power supplies; space stations, space power reactors, solar arrays, thermoelectric generators, energy storage, and communication satellites are among the topics discussed.

1984-01-01

207

Microstructural Evolution in Power Plant Steels  

E-print Network

, heat energy from fuel combustion or nuclear fission is used to produce jets of steam. The kinetic Steels Pump Cooling water Cooling water Electrical output Condenser Reheat Coal Boiler Superheater Ash HP energy of the steam is converted to electrical energy by a system of turbines and a generator. Figure 2

Cambridge, University of

208

Preliminary demonstration of power beaming with non-coherent laser diode arrays  

SciTech Connect

A preliminary demonstration of free-space electric power transmission has been conducted using non-coherent laser diode arrays as the transmitter and standard silicon photovoltaic cell arrays as the receiver. The transmitter assembly used a high-power-density array of infrared laser diode bars, water cooled via integrated microchannel heat sinks and focused by cylindrical microlenses. The diode array composite beam was refocused by a parabolic mirror over a 10 meter path, and received on a {approximately}15 x 25 cm panel of thinned single crystal high efficiency silicon solar cells. The maximum cell output obtained was several watts, and the cell output was used to drive a small motor. Due to operating constraints and unexpected effects, particularly the high nonuniformity of the output beam, both the distance and total received power in this demonstration were modest. However, the existing transmitter is capable of supplying several hundred watts of light output, with a projected received electric power in excess of 200 watts. The source radiance is approximately 5 x 10{sup 9} W/m{sup 2}-steradian. With the existing 20 cm aperture, useful power transmission over ranges to {approximately}100 meters should be achievable with a DC to DC efficiency of greater than 10%. Non-coherent sources of this type are readily scalable to powers of tens of kilowatts, and with larger apertures can be used directly for power transmission up to several kilometers. Future non-coherent diode laser sources may be suitable for power transmission over hundreds of kilometers. Also, the experience gained with non-coherent arrays will be directly applicable to power beaming systems using coherent diode arrays or other array-type laser sources.

Kare, J T; Militsky, F; Weisberg, A

1999-02-26

209

Preliminary demonstration of power beaming with non-coherent laser diode arrays  

SciTech Connect

A preliminary demonstration of free-space electric power transmission has been conducted using non-coherent laser diode arrays as the transmitter and standard silicon photovoltaic cell arrays as the receiver. The transmitter assembly used a high-power-density array of infrared laser diode bars, water cooled via integrated microchannel heat sinks and focused by cylindrical microlenses. The diode array composite beam was refocused by a parabolic mirror over a 10 meter path, and received on a {approximately}15{times}25&hthinsp;cm panel of thin film high efficiency silicon solar cells. The maximum cell output obtained was several watts, and the cell output was used to drive a small motor. Due to operating constraints and unexpected effects, particularly the high nonuniformity of the output beam, both the distance and total received power in this demonstration were modest. However, the existing transmitter is capable of supplying several hundred watts of light output, with a projected received electric power in excess of 200 watts. The source radiance is approximately 5{times}10{sup 9}&hthinsp;W/m{sup 2}-steradian. With the existing 20 cm aperture, useful power transmission over ranges to {approximately}100 meters should be achievable with a DC to DC efficiency of greater than 10{percent}. Non-coherent sources of this type are readily scalable to powers of tens of kilowatts, and with larger apertures can be used directly for power transmission up to several kilometers. Future non-coherent diode laser sources may be suitable for power transmission over hundreds of kilometers. Also, the experience gained with non-coherent arrays will be directly applicable to power beaming systems using coherent diode arrays or other array-type laser sources. {copyright} {ital 1999 American Institute of Physics.}

Kare, J.T. [Kare Technical Consulting, 222 Canyon Lakes Pl., San Ramon, California 94583 (United States); Mitlitsky, F.; Weisberg, A. [Lawrence Livermore National Laboratory, L-174, P.O. Box 808, Livermore, California 94551 (United States)

1999-01-01

210

Design and operating experience of a 40 MW, highly-stabilized power supply  

NASA Astrophysics Data System (ADS)

Four 10 MW, highly-stabilized power supply modules have been installed at the National High Magnetic Field Laboratory in Tallahassee, FL, to energize water-cooled, resistive, high-field research magnets. The power supply modules achieve a long term current stability if 10 ppM over a 12 h period with a short term ripple and noise variation of less than 10 ppM over a time period of one cycle. The power supply modules can operate independently, feeding four separate magnets, or two, three or four modules can operate in parallel. Each power supply module consists of a 12.5 kV vacuum circuit breaker, two three-winding, step-down transformers, a 24-pulse rectifier with interphase reactors, and a passive and an active filter. Two different transformer tap settings allow rated dc supply output voltages of 400 and 500 V. The rated current of a supply module is 17 kA and each supply module has a one-hour overload capability of 20 kA. The isolated output terminals of each power supply module are connected to a reversing switch. An extensive high-current bus system allows the modules to be connected to 16 magnet cells. This paper presents the detailed design of the power supply components. Various test results taken during the commissioning phase with a 10 MW resistive load and results taken with the research magnets are shown. The effects of the modules on the electrical supply system and the operational behavior of the power factor correction/harmonic filters are described. Included also are results of a power supply module feeding a superconducting magnet during quench propagation tests. Problems with the power supply design and solutions are presented. Some suggestions on how to improve the performance of these supplies are outlined.

Boenig, Heinrich J.; Ferner, James A.; Bogdan, Ferenc; Morris, Gary C.; Rumrill, Ron S.

211

Influence of various types of ionizing radiation on the properties of polymers. Thermal conductivity and crystallinity of polytetrafluoroethylene  

SciTech Connect

The influence of the {gamma} radiation of {sup 60}Co, 100 MeV protons, and neutrons of a water-moderated water-cooled reactor on the thermal conductivity and crystallinity of polytetrafluoroethylene was investigated. Specific features of the type of ionizing radiation were detected under the influence of neutrons. 10 refs., 2 figs., 1 tab.

Briskman, B.A.; Rogova, V.N.; Chikina, Z.N.

1992-09-01

212

Sensitivity analysis for AHWR fuel cluster parameters using different WIMS libraries  

Microsoft Academic Search

India is presently engaged in the design of an advanced heavy water reactor (AHWR) which utilises thorium as fuel. The AHWR is a boiling light water cooled heavy water moderated reactor where the heat is removed through natural convection. Dysprosium is used as burnable absorber to get a reduction in void reactivity. The design needs to be well validated. The

Arvind Kumar; Umashankari Kannan; R. Srivenkatesan

2002-01-01

213

Solar Power  

NSDL National Science Digital Library

In this lesson,students will evaluate a location in the Northern Hemisphere and Southern Hemisphere to determine the areas best for collecting solar power. Changes in surface radiation will be evaluated using Monthly Surface Radiation data from 2007 from MyNASAData website. Students will draw conclusions about how surface radiation levels will affect choice of solar power plant location selection and infer the best location for a solar power plant.

214

Component development for 500 watt diesel fueled portable thermophotovoltaic (TPV) power supply  

NASA Astrophysics Data System (ADS)

McDermott Technology, Inc. (MTI) and JX Crystals have developed an innovative design for a compact, 500-watt, thermophotovoltaic (TPV) power supply using diesel fuel. Under a contract with the Defense Advanced Research Projects Agency (DARPA) and managed by the U.S. Army Communications-Electronics Command (CECOM), this design is being reduced to hardware. Prototypes of the two main subsystems, the power converter assembly (PCA) and the burner/emitter/recuperator (BER), have been designed, fabricated, and tested. The PCA uses low-band-gap gallium antimonide (GaSb) photovoltaic (PV) cells for high efficiency and power density. The prototype PCA will be air cooled for system simplicity and portability. However, initial testing was performed on a water-cooled PCA. The BER uses a thermal vaporizer to produce a stable, high-intensity, low-emissions combustion zone inside an impervious emitter. A thermally integrated recuperator is utilized to boost system efficiency by transferring the unused energy in the exhaust stream to the incoming fuel and combustion air. This paper describes the design, testing and performance of the first-generation PCA and BER along with model predictions used for design and evaluation.

DeBellis, Crispin L.; Scotto, Mark V.; Fraas, Lewis; Samaras, John; Watson, Ron C.; Scoles, Stephen W.

1999-03-01

215

Tidal power  

Microsoft Academic Search

Reviews the physics of tidal power, considering the gravitational effects of the Moon and Sun; semidiurnal, diurnal, and mixed tides; and major periodic components that affect the tidal range. Shelving, funneling, reflection, and resonance phenomena that have a significant effect on tidal range are also discussed. Basic parameters that govern the design of tidal power schemes in terms of mean

T. J. Hammons

1993-01-01

216

Diastatic power  

Technology Transfer Automated Retrieval System (TEKTRAN)

diastatic power: Diastatic power, abbreviated DP, is the total activity of malt starch degrading enzymes that hydrolyze starch to fermentable sugars. The starch degrading enzymes contributing to this process are a-amylase, -amylase, limit dextrinase, and a-glucosidase. The driving force for DP a...

217

POWER SYSTEMS  

Microsoft Academic Search

Low power output of other devices at this time dictates the use of ; nuclear-reactor systems for manned space explorations. Work up to the present is ; briefly reviewed, and progress and utilization of other power supplies are ; discussed. Pros and cons of solar cells, fuel cells, and thermoelectric and ; thermionic devices are included as well as consideration

1962-01-01

218

Power Source  

ERIC Educational Resources Information Center

Principals are powerful: They are the primary catalysts for creating a lasting foundation for learning, driving school and student performance, and shaping the long-term impact of school improvement efforts. Yet few principals would characterize themselves as powerful. Rather, they're self-effacing, adaptable, pragmatic, and quick to share credit

Schooley, Michael L.

2010-01-01

219

Field tests of a vertical-fluted-tube condenser in the prototype power plant at the Raft River Geothermal Test Site  

SciTech Connect

A vertical-fluted-tube condenser was designed, fabricated, and tested with isobutane as the shell-side working fluid in a binary prototype power plant at the Raft River Geothermal Test Site. After shakedown and contamination removal operations were completed, the four-pass water-cooled unit (with 102 outside-fluted Admiralty tubes) achieved performance predictions while operating with the plant surface evaporator on-line. A sample comparison shows that use of this enhanced condenser concept offers the potential for a reduction of about 65% from the size suggested by corresponding designs using conventional horizontal-smooth-tube concepts. Subsequent substitution of a direct-contact evaporator for the surface evaporator brought drastic reductions in system performance, the apparent consequence of high concentrations of noncondensible gases introduced by the brine/working-fluid interaction.

Murphy, R.W.

1983-04-01

220

Power Up!  

NSDL National Science Digital Library

In this online game, learners must purchase power plants for their city. They must balance the need for adequate power against the environmental impact of different power plants and stay within their limited budget. The game introduces many kinds of power plants to choose from (oil, coal, nuclear, solar, wind, hydro). Since the game only shows a random selection of three of these power sources at a time, the game changes each time you play. When learners set up a free account at Kinetic City, they can answer bonus questions at the end of the activity as a quick assessment. As a larger assessment, learners can complete the Smart Attack game after they've completed several activities.

2012-01-10

221

Investigation of a Stirling-type pulse tube cryocooler with 100 W-class cooling power at 77 K  

NASA Astrophysics Data System (ADS)

High power Stirling-type pulse tube cryocoolers are considered as one of the ideal candidates for cooling high temperature superconducting devices for its high reliability and high efficiency. The inhomogeneity of flow in a large-diameter pulse tube is one of the main obstacles to develop an efficient cryocooler. In this paper, a Stirling-type pulse tube cryocooler with 100 W-class cooling power at 77 K was developed and tested. A screen-filled secondary water-cooled heat exchanger is used at the hot end of the pulse tube to suppress the jet steaming. Then, attentions were focused on the influence of the pulse tube configurations on the cooling performance. Pulse tubes with different size and taper angle were investigated. With a 100 mm-long cylindrical pulse tube, a cooling power of more than 100 W at 77 K was obtained, and with a 75 mm-long tapered pulse tube of 2.8, the relative Carnot efficiency of the cryocooler from acoustic work to cooling power reached 29.8%. If the efficiency of the compressor is 80%, the relative Carnot efficiency of the whole system could reach about 24%, showing great attraction to HTS applications.

Zhang, L. M.; Hu, J. Y.; Chen, Y. Y.; Luo, E. C.; Dai, W.

2014-01-01

222

Thrust stand for high-power electric propulsion devices  

NASA Astrophysics Data System (ADS)

A thrust stand for use with magnetoplasmadynamic (MPD) thrusters operated at powers up to 250 kW steady state has been built and tested. The stand was based on an inverted pendulum configuration which resulted in large displacements and high resolution. Up to 50 mm of deflection was observed under a force of 5 N. This large range of displacement significantly reduced the effects of facility induced vibrations on thrust measurements. A remotely operated system was provided for in situ calibration of the thrust stand prior to and immediately after data were obtained. Calibrations showed that thrust measurements were linear and repeatable to within a fraction of 1%. Structural distortions of the vacuum facility due to pumpdown were detected with an inclinometer located in the thrust stand base. Slope deviations as small as 10 arcsec could be compensated using a remotely controlled leveling motor. Early problems with magnetically induced tares caused by the thruster discharge current were reduced by rerouting high-current cables to decrease stray fields. Tares due to discharge current were on the order of 26 mN at 3000 A, and those due to an applied field current were 63 mN at 1400 A. The thrust stand was used with a water-cooled, applied field, steady-state MPD device at power levels up to 125 kW. Hot thruster firings as long as 1 h were performed. By precisely maintaining a level thrust stand base, thermal drift was held to about 2% of the full scale reading over this period. The remaining thermal drift could be subtracted from the thrust measurement to further reduce systematic error. Tares caused by the applied magnetic field were similarly removed. By subtracting tabulated discharge current magnetic tares, thrust measurement uncertainty was reduced to approximately 2% of the measured value.

Haag, T. W.

1991-05-01

223

Power performance  

SciTech Connect

Two power generation engineering and construction firms with international markets are briefly described in this article. Bibb and Associates and Black & Veatch, both Kansas-based companies, are discussed. Current projects and services provided by the companies are described.

Anderson, J.

1996-04-01

224

Power performance  

Microsoft Academic Search

Two power generation engineering and construction firms with international markets are briefly described in this article. Bibb and Associates and Black & Veatch, both Kansas-based companies, are discussed. Current projects and services provided by the companies are described.

1996-01-01

225

Power Factor  

NSDL National Science Digital Library

All About Circuits is a website that ??provides a series of online textbooks covering electricity and electronics.? Written by Tony R. Kuphaldt, the textbooks available here are wonderful resources for students, teachers, and anyone who is interested in learning more about electronics. This specific section, Power Factor, is the eleventh chapter in Volume II ??Alternating Current. A few of the topics covered in this chapter include: True, Reactive, and Apparent power; Calculating power factor, and Practical power factor correction. Diagrams and detailed descriptions of concepts are included throughout the chapter to provide users with a comprehensive lesson. Visitors to the site are also encouraged to discuss concepts and topics using the All About Circuits discussion forums (registration with the site is required to post materials).

Kuphaldt, Tony R.

226

Anode power deposition in an applied-field segmented anode MPD thruster  

NASA Technical Reports Server (NTRS)

Anode heat flux measurements of a water cooled segmented anode applied-field MPD thruster were made to investigate anode heat transfer phenomena. Pure argon and argon-hydrogen mixtures were used as propellants for a variety of thruster currents, propellant mass flow rates, and axial applied magnetic field strengths. The thruster was operated in two modes; with all four segments active, and with two of the segments floating. In addition, thrust and specific impulse were determined for each operating condition. The results show that the heat flux to the anode increases monotonically with axial magnetic field strength and thruster current. Between 50 and 75 percent of the anode heat flux is transported by the current carrying electrons. Convective and radiative heat transfer account for the remaining portion of the power deposited in the anode. The addition of hydrogen to the argon propellant results in the reduction of the fraction of anode power deposited by the anode fall to a level equivalent to that deposited by convection and radiation.

Myers, R. M.; Kelly, A. J.; Jahn, R. G.; Gallimore, A. D.

1991-01-01

227

Power inverters  

DOEpatents

Power inverters include a frame and a power module. The frame has a sidewall including an opening and defining a fluid passageway. The power module is coupled to the frame over the opening and includes a substrate, die, and an encasement. The substrate includes a first side, a second side, a center, an outer periphery, and an outer edge, and the first side of the substrate comprises a first outer layer including a metal material. The die are positioned in the substrate center and are coupled to the substrate first side. The encasement is molded over the outer periphery on the substrate first side, the substrate second side, and the substrate outer edge and around the die. The encasement, coupled to the substrate, forms a seal with the metal material. The second side of the substrate is positioned to directly contact a fluid flowing through the fluid passageway.

Miller, David H. (Redondo Beach, CA); Korich, Mark D. (Chino Hills, CA); Smith, Gregory S. (Woodland Hills, CA)

2011-11-15

228

Tacoma Power Weatherization  

E-print Network

Tacoma Power Weatherization Specifications August 2009 KnowYourPower.com | #12;TACOMA POWER WEATHERIZATION SPECIFICATIONS 2009 edition Page 2 #12;TACOMA POWER WEATHERIZATION SPECIFICATIONS 2009 edition

229

Power branding  

SciTech Connect

For most of its century-long history, electricity was a natural monopoly, due in part to the excessive cost of the necessary infrastructure. In the past decade, however, politics have pushed the industry toward competition and consumer choice. At the same time, technology has been developed that allows consumers to choose their electricity supplier and to track the flow of power through the various grids and lines. In her new book, Power Branding, author and industry expert Ann Chambers examines marketing and branding of electricity -- what it is, how it`s done, what its benefits are for electric utilities, marketers, and even natural gas companies allied with the utilities. She surveys industry leaders who have already taken a dive into the ocean of marketing and offers lessons drawn from their experiences. She also takes a look at other formerly regulated industries -- airlines, telephone, natural gas -- and describes how their rebirth as free-market industries may affect the course of the electric utility industry`s experience. The contents include: Introduction; Basics of branding: Brand image; Value-added services; Southern Company; Duke Energy; UtiliCorp/EnergyOne/Aquila--big and brand; Engage energy; Florida Power and Light Co.; Enron; Convergence; Lessons from the natural gas industry; Lessons from other industries; Conclusion; Resources; Glossary of branding, marketing and Btu convergence; and Major federal legislation affecting the electric power industry.

Chambers, A.

1998-12-31

230

Power sprouts  

NASA Astrophysics Data System (ADS)

This paper explains how a large number of sprouts were used as a battery of cells and connected together to power a set of LED Christmas lights. All relevant calculations to find the number of sprouts needed, their arrangement in series and parallel, the charge stored on the required capacitor and the capacitor charging time are illustrated.

French, M. M. J.

2014-05-01

231

Star Power  

ScienceCinema

The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

None

2014-11-18

232

POWER SEWING.  

ERIC Educational Resources Information Center

ALTHOUGH THE PRIMARY PURPOSE OF THIS STUDY GUIDE IS TO PROVIDE A TEXT IN POWER SEWING FOR DEAF PUPILS, IT CAN ALSO BE USED FOR STUDENTS WITH READING OR LEARNING DIFFICULTIES. DEVELOPED BY AN INSTRUCTOR WITH FACULTY HELP, THE TEXT FOLLOWS A COURSE OF STUDY APPROVED BY THE BOARD OF EDUCATION AND HAS BEEN TESTED IN VARIOUS CLASSROOMS. UNITS ARE --

HILLINGER, YVONNE M.

233

Power Trains.  

ERIC Educational Resources Information Center

This curriculum guide is part of a series designed to teach students about diesel engines. The materials in this power trains guide apply to both on-road and off-road vehicles and include information about chain and belt drives used in tractors and combines. These instructional materials, containing nine units, are written in terms of student

Kukuk, Marvin; Mathis, Joe

234

Nuclear Power  

NSDL National Science Digital Library

An introduction to nuclear fission, its controlled release in power stations, problems of nuclear waste, and nuclear accidents. A linked web page discusses nuclear weapons, their effect, their ban, and "dirty bombs". This material supplements a previous section on fission in the Sun and the curve of binding energy in "From Stargazers to Starships". A French translation also exists.

Stern, David

2004-11-28

235

Star Power  

SciTech Connect

The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

None

2014-10-17

236

Stigma power.  

PubMed

When people have an interest in keeping other people down, in or away, stigma is a resource that allows them to obtain ends they desire. We call this resource "stigma power" and use the term to refer to instances in which stigma processes achieve the aims of stigmatizers with respect to the exploitation, control or exclusion of others. We draw on Bourdieu (1987, 1990) who notes that power is often most effectively deployed when it is hidden or "misrecognized." To explore the utility of the stigma-power concept we examine ways in which the goals of stigmatizers are achieved but hidden in the stigma coping efforts of people with mental illnesses. We developed new self-report measures and administered them to a sample of individuals who have experienced mental illness to test whether results are consistent with the possibility that, in response to negative societal conceptions, the attitudes, beliefs and behaviors of people with psychosis lead them to be concerned with staying in, propelled to stay away and induced to feel downwardly placed - precisely the outcomes stigmatizers might desire. Our introduction of the stigma-power concept carries the possibility of seeing stigmatizing circumstances in a new light. PMID:24507908

Link, Bruce G; Phelan, Jo

2014-02-01

237

Power Factor Compensation (PFC) Power Factor Compensation  

E-print Network

Power Factor Compensation (PFC) Power Factor Compensation The power factor (PF) is defined as the ratio between the active power and the apparent power of a system. If the current and voltage are periodic with period , and [ ), then the active power is defined by ( ) ( ) (their inner product

Knobloch,Jürgen

238

Power converter  

NASA Technical Reports Server (NTRS)

A dc-to-dc converter employs four transistor switches in a bridge to chop dc power from a source, and a voltage multiplying diode rectifying ladder network to rectify and filter the chopped dc power for delivery to a load. The bridge switches are cross coupled in order for diagonally opposite pairs to turn on and off together using RC networks for the cross coupling to achieve the mode of operation of a free running multivibrator, and the diode rectifying ladder is configured to operate in a push-pull mode driven from opposite sides of the multivibrator outputs of the ridge switches. The four transistor switches provide a square-wave output voltage which as a peak-to-peak amplitude that is twice the input dc voltage, and is thus useful as a dc-to-ac inverter.

Black, J. M. (inventor)

1981-01-01

239

Wireless Power Transmission Technology State-Of-The-Art  

NASA Astrophysics Data System (ADS)

This first Bill Brown SSP La Crescenta, CA 91214 technology , including microwave and laser systems for the transfer of electric , as related to eventually developing Space Solar Power (SSP) systems. Current and past technology accomplishments in ground based and air and space applied energy conversion devices, systems and modeling performance and cost information is presented, where such data are known to the author. The purpose of the presentation is to discuss and present data to encourage documenting and breaking the current technology records, so as to advance the SOA in WPT for SSP . For example, regarding DC to RF and laser converters, 83% efficient 2.45 GHz cooker-tube magnetrons with 800W CW output have been jointly developed by Russia and US. Over 50% wa11-plug efficient 1.5 kW/cm2 CW, water cooled, multibeam, solid state laser diode bar-arrays have been developed by LLNL at 808 nm wavelength. The Gennans have developed a 36% efficient, kW level, sing1e coherent beam, lateral pumped semiconductor laser. The record for end-to-end DC input to DC output power overall WPT link conversion efficiency is 54% during the Raytheon-JPL experiments in 1975 for 495.6 W recovered at 1.7-mrange at 2.4469 GAz. The record for usefully recovered electric power output ( as contrasted with thennally induced power in structures) is 34 kW OC output at a range of 1.55 km, using 2.388 GHz microwaves, during the JPL- Raytheon experiments by Bill Brown and the author at Goldstone, CA in 1975. The GaAs-diode rectenna array had an average collection-conversion efficiency of 82.5%. A single rectenna element operating a 6W RF input, developed by Bill Brown demonstrated 91.4% efficiency. The comparable record for laser light to OC output power conversion efficiency of photovoltaics is 590/0. for AlGaAs at 1.7 Wand 826nm wavelength. Russian cyclotron-wave converters have demonstrated 80% rectification efficiency at S-band. Concerning WPT technology equipment costs, magnetron conversion devices for microwave ovens are approximately O.O25/W, due to the large manufacturing quantities. Comparable, remanufactured lasers for industrial applications at the 4 kW CW level are of order 25/W. Industrial klystrons cost over 1/W and solid state power amplifiers cost over 3/W. Model tethered helicopters, model airplanes, a smal1 airship and several small rovers have been powered with microwave beams at 2.45, 5.8 and 35 GHz. Smal1 rovers have been powered with laser beams. Two space-to-space microwave power link experiments have been conducted by the Japanese and with Texas A&M assistance in one case. International records for WPT link electric power delivered, range, 1ink efficiency and other salient parameters for both wireless-laser and -microwave power demonstrations win be reviewed. Also, costing models for WPT -system figure- of-merit (FOM) in terms of capital costs, in /MW -km, as a fonction of range and power level are reviewed. Records in Japan. France, Korea, Russia, Canada and the US will be reviewed for various land based WPT demonstrations. SSP applicable elements of technology in fiber and wireless links, cell phones and base stations, aircraft, and spacecraft phased arrays, industrial and scientific klystrons and lasers, military equipment (where information is available in open literature) microwave heating, and other telecommunication activities win be presented, concerning power handling, frequency or wavelength, conversion efficiency, specific mass, specific cost, etc. Previously studied and proposed applications of WPT technology will be presented to show the range of WPT technology being considered for commercial and other applications that will lead to advancing the SOA of WPT technology that win benefit SSP .

Dickinson, R. M. T.

2002-01-01

240

Power saw  

NASA Technical Reports Server (NTRS)

A power saw is disclosed for space or robotic operations with jaw members for clamping to a work piece by an operation of a lever arm. The saw assembly is slidably mounted on the jaw assembly and fed into the work piece by a hand operated feed screw. The saw assembly includes a motor and gear belt. A current sensing circuit provides a current signal which actuates colored lights to visually depict the load on the saw blade during the cutting operations.

Bradley, Jimmy D. (inventor)

1991-01-01

241

Power Source  

NSDL National Science Digital Library

Students engage in this brief activity at the start of a module on fossil energy and power generation with no advance notice. They are first asked to form pairs or groups of three (in a large lecture hall, students usually work with adjacent classmates) and to take out a blank sheet of paper. The instructor asks the students to consider the lowly 110-V wall socket: it provides electrical power for their appliances-- but do they know, and can they show, where that power comes from? Without elaboration, they are asked to trace its source as far back as they can envision. If necessary, the instructor can give the basic procedure for concept sketching (after Johnson & Reynolds 2005): list what they know, depict their ideas in an organized sketch, and annotate all of the components with descriptive phrases or short sentences. The class is informed that the sketches will be collected for participation credit. Artistic quality is not required or expected, but students are encouraged to make their sketches as detailed as they can, perhaps for additional credit. Each group may designate one student to sketch, but all members must contribute their ideas. After about 10 minutes or a noticeable decrease in conversation volume, and if time and logistics permit, the instructor may ask some or all of the groups to present their sketches to the class for review and discussion. (To facilitate this, groups may instead be given transparencies and markers and use an overhead projector.) Each student is reminded to put her or his name on the sketch before it is submitted. After the activity is complete, the instructor may present his or her own version of this concept sketch (illustrating the present-day local or national energy mix; an example is attached here), or simply proceed into a lecture presentation or discussion on the topic of energy. Students may also be directed to research the electrical power grid or the national energy mix as a homework assignment.

Steven Semken

242

Hydroelectric Power  

NSDL National Science Digital Library

USGS Science for Schools explains how electrical power is generated from a dam. A clear illustration labels the parts of a generator, from the stator to the turbine blades. A motion diagram shows the movement of water through the process for easy understanding. Visitors will also find links to a number of related topics, such as water use, from the USGS Science for Schools sites.

2008-05-07

243

Paddle Power  

NSDL National Science Digital Library

In this design challenge, learners build a boat that paddles itself using a rubber band as its power source. Learners follow the design process to make a boat out of cups, design and build working paddles, use rubber bands to store and release energy, and figure out ways to attach their paddles to their boats. This is a great activity for lessons on engineering and potential/kinetic energy.

Wgbh

2010-01-01

244

Knowledges and abilities catalog for nuclear power plant operators: Savannah River Site (SRS) production reactors  

SciTech Connect

The Knowledges and Abilities Catalog for Nuclear Power Plant Operations: Savannah River Site (SRS) Production Reactors, provides the basis for the development of content-valid certification examinations for Senior Reactor Operators (SROs) and Central Control Room Supervisors (SUP). The position of Shift Technical Engineer (STE) has been included in the catalog for completeness. This new SRS reactor operating shift crew position is held by an individual holding a CCR Supervisor Certification who has received special engineering and technical training. Also, the STE has a Bachelor of Science degree in engineering or a related technical field. The SRS catalog contains approximately 2500 knowledge and ability (K/A) statements for SROs and SUPs at heavy water moderated production reactors. Each K/A statement has been rated for its importance to the safe operation of the plant in a manner ensuring the health and safety of the public. The SRS K/A catalog is presently organized into five major sections: Plant Systems grouped by Safety Function, Plant Wide Generic K/As, Emergency Plant Evolutions, Theory and Components (to be developed).

Not Available

1990-06-20

245

Tidal power  

SciTech Connect

The paper reviews the physics of tidal power considering gravitational effects of moon and sun; semidiurnal, diurnal, and mixed tides; and major periodic components that affect the tidal range. Shelving, funneling, reflection, and resonance phenomena that have a significant effect on tidal range are also discussed. The paper then examines tidal energy resource for principal developments estimated from parametric modeling in Europe and worldwide. Basic parameters that govern the design of tidal power schemes in terms of mean tidal range and surface area of the enclosed basin are identified. While energy extracted is proportional to the tidal amplitude squared, requisite sluicing are is proportional to the square root of the tidal amplitude. Sites with large tidal amplitudes are therefore best suited for tidal power developments, whereas sites with low tidal amplitudes have sluicing that may be prohibitive. It is shown that 48% of the European tidal resource is in the United Kingdom, 42% in France and 8% in Ireland, other countries having negligible potential. Worldwide tidal resource is identified. Tidal barrage design and construction using caissons is examined, as are alternative operating modes (single-action generation, outflow generation, flood generation, two-way generation, twin basin generation, pumping, etc), development trends and possibilities, generation cost at the barrage boundary, sensitivity to discount rates, general economics, and markets. Environmental effects, and institutional constraints to the development of tidal barrage schemes are also discussed.

Hammons, T.J. (Glasgow Univ., Scotland (United Kingdom))

1993-03-01

246

Free electron laser with small period wiggler and sheet electron beam: A study of the feasibility of operation at 300 GHz with 1 MW CW output power  

SciTech Connect

The use of a small period wiggler (/ell//sub ..omega../ < 1 cm) together with a sheet electron beam has been proposed as a low cost source of power for electron cyclotron resonance heating (ECRH) in magnetic fusion plasmas. Other potential applications include space-based radar systems. We have experimentally demonstrated stable propagation of a sheet beam (18 A. 1 mm /times/ 20 mm) through a ten-period wiggler electromagnet with peak field of 1.2 kG. Calculation of microwave wall heating and pressurized water cooling have also been carried out, and indicate the feasibility of operating a near-millimeter, sheet beam FEL with an output power of 1 MW CW (corresponding to power density into the walls of 2 kW/cm/sup 2/). Based on these encouraging results, a proof-of-principle experiment is being assembled, and is aimed at demonstrating FEL operating at 120 GHz with 300 kW output power in 1 ..mu..s pulses: electron energy would be 410 keV. Preliminary design of a 300 GHz 1 MW FEL with an untapered wiggler is also presented. 10 refs., 5 figs., 3 tabs.

Booske, J.H.; Granatstein, V.L.; Antonsen, T.M. Jr.; Destler, W.W.; Finn, J.; Latham, P.E.; Levush, B.; Mayergoyz, I.D.; Radack, D.; Rodgers, J.

1988-01-01

247

Lunar solar-power system: Commerical power  

Microsoft Academic Search

The proposed Lunar Solar-Power (LSP) System collects solar power on the moon. The power is converted to beams of microwaves and transmitted to fields of microwave receivers (rectennas) on Earth that provide electric power to local and regional power grids. LSP can provide abundant and low cost energy to Earth to sustain several centuries of economic development on Earth and

David R. Criswell

1995-01-01

248

Power Play  

NSDL National Science Digital Library

In this online game, learners build complicated machines to complete simple tasks. The game starts with a power source on one side of the screen and the task on the other side. Learners select machine parts to link together and complete the task. The machine parts follow simple physics rules. When learners set up a free account at Kinetic City, they can answer bonus questions at the end of the activity as a quick assessment. As a larger assessment, learners can complete the Bug Blaster game after they've completed several activities.

American Association for the Advancement of Science

2009-01-01

249

Nuclear Power  

E-print Network

Cover Designer Martina Sirotic Image Copyright TebNad, ?#5;#6;#5;. Used under license from Shutterstock.com First published September ?#5;#6;#5; Printed in India A free online edition of this book is available at www.sciyo.com Additional hard copies... can be obtained from publication@sciyo.com Nuclear Power, Edited by Pavel V. Tsvetkov p. cm. ISBN ??- #7;?-?#5;?-#6;#6;#5;-? SCIYO.COM WHERE KNOWLEDGE IS FREE free online editions of Sciyo Books, Journals and Videos can be found at www.sciyo.com...

250

Power Quality  

Microsoft Academic Search

\\u000a Providing power quality (PQ) for 21st-century needs is one of the widely accepted principal characteristics of the envisioned\\u000a Smart Grid because we will have more and more PQ-sensitive loads such as microprocessor-based devices, critical manufacturing\\u000a processes, and data centers [1]. Our future global competitiveness demands disturbance-free operation of the digital devices\\u000a that empower the productivity of our economy. It is

Kyeon Hur; Surya Santoso

251

Girl Power  

NSDL National Science Digital Library

Launched in 1996 by former US Department of Health and Human Services Secretary Donna Shalala, the Girl Power! Program seeks to encourage 9 to 13 year-old girls to make the most of their lives, and "to support and nurture girls in order for them to be confident, fulfilled, and true to themselves." With that in mind, this Web site is designed to be a clearinghouse of information, press releases, and activities for both parents and young women alike. The section for parents contains information about ongoing activities sponsored and endorsed by Girl Power, along with current cultural quizzes that will help keep parents in touch with their children. The area for young women features an interactive school locker that contains a "talk-back" section, fun games and activities, and information on healthy eating habits and maintaining a balanced body image. The last section on the site provides links to external sites dealing with surveys and studies on young women, such as ones dealing with substance abuse, perceived threats, and gender roles.

252

Power Controller  

NASA Astrophysics Data System (ADS)

The device called the Power Factor Controller (PFC) offers exceptional energy conservation potential by virtue of its ability to sense shifts in the relationship between voltage and current flow, and to match them with the motor's need. Originating from the solar heating/cooling program, the PFC senses a light load, it cuts the voltage level to the minimum needed which in turn reduces current flow and heat loss. Laboratory tests showed that the PFC could reduce power used by six to eight percent under normal motor loads, and as much as 65 percent when the motor was idling. Over 150 companies have been granted NASA licenses for commercial use of this technology. One system that utilizes this technology is the Vectrol Energy System, (VES) produced by Vectrol, Inc. a subsidiary of Westinghouse. The VES is being used at Woodward & Lothrop, on their escalators. Energy use is regulated according to how many people are on the escalator at any time. It is estimated that the energy savings are between 30 to 40 percent.

1982-01-01

253

Power optics  

NASA Astrophysics Data System (ADS)

By using the theory we developed in the early 1970s, a broad range of phenomena is considered for an optical surface of a solid body that is exposed to radiation arbitrarily varying in time and producing temperature fields, thermoelastic stresses and thermal deformations on the surface layer. The examination is based on the relations (which are similar to Duhamel's integral formula from the theory of heat conduction) between the quantities characterising the thermal stress state in any nonstationary regimes of energy input into a solid. A peculiar feature of the analysis of the thermal stress state in this case consists in the fact that this relation comprises time as a parameter, which in turn is a consequence of incoherence of the quasi-stationary problem of thermoelasticity. This phenomenon is particularly important for the optics of high-power, high-pulse repetition rate lasers, which are being actively developed. In the review, we have recently published in Laser Physics, the thermal stress state of a solid is analysed. In this state, time is treated as an independent variable used in differentiation. Such an approach greatly reduces the applicability of the method. The review published contains data on the use of capillary porous structures made of various materials with different degrees of the surface development. Moreover, such structures can be efficiently employed to increase the heat exchange at a temperature below the boiling point of the coolant. In the present review we discuss the dependences of the limiting laser intensities on the duration of a pulse or a pulse train, corresponding to the three stages of the state of the reflecting surface and leading to unacceptable elastic deformations of the surface, to the plastic yield of the material accompanied by the formation of residual stresses and to the melting of the surface layer. We also analyse the problem of heat exchange in the surface layer with a liquid metal coolant pumped through it. The theoretical estimates are compared with the experimental data. We discuss the issues related to the technology of fabrication of power optics elements based on materials with a porous structure, of lightweight highly stable large optics based on highly porous materials, multi-layer honeycomb structures and silicon carbide, as well as problems of application of physical and technical fundamentals of power optics in modern cutting-edge technology.

Apollonov, V. V.

2014-02-01

254

Powerful Pulleys  

NSDL National Science Digital Library

Students continue to explore the story of building a pyramid, learning about the simple machine called a pulley. They learn how a pulley can be used to change the direction of applied forces and move/lift extremely heavy objects, and the powerful mechanical advantages of using a multiple-pulley system. Students perform a simple demonstration to see the mechanical advantage of using a pulley, and they identify modern day engineering applications of pulleys. In a hands-on activity, they see how a pulley can change the direction of a force, the difference between fixed and movable pulleys, and the mechanical advantage gained with multiple / combined pulleys. They also learn the many ways engineers use pulleys for everyday purposes.

Integrated Teaching and Learning Program,

255

Power oscillator  

DOEpatents

An oscillator includes an amplifier having an input and an output, and an impedance transformation network connected between the input of the amplifier and the output of the amplifier, wherein the impedance transformation network is configured to provide suitable positive feedback from the output of the amplifier to the input of the amplifier to initiate and sustain an oscillating condition, and wherein the impedance transformation network is configured to protect the input of the amplifier from a destructive feedback signal. One example of the oscillator is a single active element device capable of providing over 70 watts of power at over 70% efficiency. Various control circuits may be employed to match the driving frequency of the oscillator to a plurality of tuning states of the lamp.

Gitsevich, Aleksandr (Montgomery Village, MD)

2001-01-01

256

FUTURE POWER GRID INITIATIVE Future Power Grid  

E-print Network

FUTURE POWER GRID INITIATIVE Future Power Grid Control Paradigm OBJECTIVE This project line power) after contingencies - Coordinate voltage resources to improve voltage security margin) to quickly stabilize system - Modify AGC to only focus on restoring tie line power to scheduled values

257

Electric power trends  

SciTech Connect

This book provides information about the forces shaping the electric power industry. It provides data on trends in the electric power industry, such as: electric utility ownership; sources of energy; industrial electricity demand; manufacturing energy for heat and power; fossil fuels consumed in electric power generation; electric power transmission; nuclear power plant generators; and residential energy consumption.

Not Available

1989-01-01

258

ESBWR response to an extended station blackout/loss of all AC power  

SciTech Connect

U.S. federal regulations require light water cooled nuclear power plants to cope with Station Blackouts for a predetermined amount of time based on design factors for the plant. U.S. regulations define Station Blackout (SBO) as a loss of the offsite electric power system concurrent with turbine trip and unavailability of the onsite emergency AC power system. According to U.S. regulations, typically the coping period for an SBO is 4 hours and can be as long as 16 hours for currently operating BWR plants. Being able to cope with an SBO and loss of all AC power is required by international regulators as well. The U.S. licensing basis for the ESBWR is a coping period of 72 hours for an SBO based on U.S. NRC requirements for passive safety plants. In the event of an extended SBO (viz., greater than 72 hours), the ESBWR response shows that the design is able to cope with the event for at least 7 days without AC electrical power or operator action. ESBWR is a Generation III+ reactor design with an array of passive safety systems. The ESBWR primary success path for mitigation of an SBO event is the Isolation Condenser System (ICS). The ICS is a passive, closed loop, safety system that initiates automatically on a loss of power. Upon Station Blackout or loss of all AC power, the ICS begins removing decay heat from the Reactor Pressure Vessel (RPV) by (i) condensing the steam into water in heat exchangers located in pools of water above the containment, and (ii) transferring the decay heat to the atmosphere. The condensed water is then returned by gravity to cool the reactor again. The ICS alone is capable of maintaining the ESBWR in a safe shutdown condition after an SBO for an extended period. The fuel remains covered throughout the SBO event. The ICS is able to remove decay heat from the RPV for at least 7 days and maintains the reactor in a safe shutdown condition. The water level in the RPV remains well above the top of active fuel for the duration of the SBO event. Beyond 7 days, only a few simple actions are needed to cope with the SBO for an indefinite amount of time. The operation of the ICS as the primary success path for mitigation of an SBO, allows for near immediate plant restart once power is restored. (authors)

Barrett, A. J.; Marquino, W. [New Plants Engineering, GE Hitachi Nuclear Energy, M/CA 75, 3901 Castle Hayne Road, Wilmington, NC 28402 (United States)

2012-07-01

259

Electric power 2007  

SciTech Connect

Subjects covered include: power industry trends - near term fuel strategies - price/quality/delivery/opportunity; generating fleet optimization and plant optimization; power plant safety and security; coal power plants - upgrades and new capacity; IGCC, advanced combustion and CO{sub 2} capture technologies; gas turbine and combined cycle power plants; nuclear power; renewable power; plant operations and maintenance; power plant components - design and operation; environmental; regulatory issues, strategies and technologies; and advanced energy strategies and technologies. The presentations are in pdf format.

NONE

2007-07-01

260

Power electronics for low power arcjets  

NASA Technical Reports Server (NTRS)

In anticipation of the needs of future light-weight low-power spacecraft, arcjet power electronics in the 100- to 400-W operating range were developed. Power topologies similar to those in the higher 2-kW and 5- to 30-kW power range were implemented, including a four-transistor bridge-switching circuit, current-mode pulse-width modulated control, and an output current averaging inductor with an integral pulse generation winding. Reduction of switching transients was accomplished using a low inductance power distribution network, and no passive snubber circuits were necessary for power switch protection. Phase shift control of the power bridge was accomplished using an improved pulse width modulation to phase shift converter circuit. These features, along with conservative magnetics designs, allowed power conversion efficiencies of greater than 92.5 percent to be achieved into resistive loads over the entire operating range of the converter.

Hamley, John A.; Hill, Gerald M.

1991-01-01

261

Magnetic power losses in [(Fe1-xCox)75B20Si5]93Nb4Y3 (x = 0, 0.2, 0.4) bulk metallic glasses  

NASA Astrophysics Data System (ADS)

Magnetic power losses of [(Fe1-xCox)75B20Si5]93Nb4Y3 (x = 0, 0.2, 0.4) metallic glasses have been investigated. Bulk samples were prepared by water-cooled Cu-mold injection casting technique with shapes of cylinders (0.8 mm diameter and 30 mm length) and toroids (10 mm external diameter and 0.5 mm thickness). Ribbons prepared by the melt- spinning technique were also analyzed. Glassy structures were confirmed by the presence of a main halo in XRD and by crystallization signal in DSC. Power losses were studied with a digital wattmeter over a range of frequencies from 1 to 400 Hz at selected peak inductions. Ribbons show smaller losses than bulk samples, presenting 24.5 J/m3 at 50 Hz and 0.65 T peak induction. It was observed that the Co addition reduces significantly the power losses. A separation theory was applied in order to explain the square root behavior of the measured power losses as a function of frequency and the results are in good agreement with the experimental data. The magnetic data were used to identify the presence of crystalline inclusions in the magnetic bulk metallic glasses. The effect of sample shape and composition on magnetic properties will be discussed.

Piccin, R.; Tiberto, P.; Chiriac, H.; Baricco, M.

2009-01-01

262

High rep rate high performance plasma focus as a powerful radiation source  

SciTech Connect

Basic operational characteristics of the plasma focus are considered from design perspectives to develop powerful radiation sources. Using these ideas the authors have developed two compact plasma focus (CPF) devices operating in neon with high performance and high repetition rate capacity for use as an intense soft X-ray (SXR) source for microelectronics lithography. The NX1 is a four-module system with a peak current of 320 kA when the capacitor bank (7.8 {micro}F {times} 4) is charged to 14 kV. It produces 100 J of SXR per shot (4% wall plug efficiency) giving at 3 Hz, 300 W of average SXR power into 4{pi}. The NX2 is also a four-module system. Each module uses a rail gap switching 12 capacitors each with a capacity of 0.6 {micro}F. The NX2 operates with peak currents of 400 kA at 11.5 kV into water-cooled electrodes at repetition rates up to 16 Hz to produce 300 W SXR in burst durations of several minutes. SXR lithographs are taken from both machines to demonstrate that sufficient SXR lithographs are taken from both machines to demonstrate that sufficient SXR flux is generated for an exposure with only 300 shots. In addition, flash electron lithographs are also obtained requiring only ten shots per exposure. Such high performance compact machines may be improved to yield over 1 kW of SXR, enabling sufficient exposure throughput to be of interest to the wafer industry. In deuterium the neutron yield could be over 10{sup 10} neutrons per second over prolonged bursts of minutes.

Lee, S.; Lee, P.; Zhang, G.; Feng, X.; Liu, M.; Serban, A.; Wong, T.K.S. [Nanyang Technological Univ. (Singapore); Gribkov, V.A. [Russian Academy of Sciences, Moscow (Russian Federation)

1998-08-01

263

Synchronous Generator with HTS-2G field coils for Windmills with output power 1 MW  

NASA Astrophysics Data System (ADS)

Nowadays synchronous generators for wind-mills are developed worldwide. The cost of the generator is determined by its size and weight. In this deal the implementation of HTS-2G generators is very perspective. The application of HTS 2G field coils in the rotor allows to reduce the size of the generator is 1.75 times. In this work the design 1 MW HTS-2G generator is considered. The designed 1 MW HTS-2G generator has the following parameters: rotor diameter 800 mm, active length 400 mm, phase voltage 690V, rotor speed 600 min-1 rotor field coils with HTS-2G tapes. HTS-2G field coils located in the rotating cryostat and cooled by liquid nitrogen. The simulation and optimization of HTS-2G field coils geometry allowed to increase feed DC current up to 50A. Copper stator windings are water cooled. Magnetic and electrical losses in 1 MW HTS-2G generator do not exceed 1.6% of the nominal output power. In the construction of HTS-2G generator the wave multiplier with ratio 1:40 is used. The latter allows to reduce the total mass of HTS-2G generator down to 1.5 tons. The small-scale model of HTS-2G generator with output power 50 kW was designed, manufactured and tested. The test results showed good agreement with calculation results. The manufacturing of 1 MW HTS-2G generator is planned in 2014. This work is done under support of Rosatom within the frames of Russian Project "Superconducting Industry".

Kovalev, K.; Kovalev, L.; Poltavets, V.; Samsonovich, S.; Ilyasov, R.; Levin, A.; Surin, M.

2014-05-01

264

Dynamic Power Systems for Power Generation  

NASA Technical Reports Server (NTRS)

The characteristics of dynamic power systems have considerable potential value, especially for the space station. The base of technology that makes these dynamic power systems practical is reviewed. The following types of power-generating systems are examined herein: organic Rankine cycle, potassium Rankine cycle, Brayton cycle, and Stirling cycle.

English, R. E.

1984-01-01

265

LIFE Power Plant Fusion Power Associates  

E-print Network

LIFE Power Plant Fusion Power Associates December 14, 2011 Mike Dunne LLNL #12;NIf-1111-23714.ppt LIFE power plant 2 #12;LIFE delivery timescale NIf-1111-23714.ppt 3 #12;Timely delivery is enabled fusion options exist. NIF/LIFE allows timely integrated demonstration. · Fusion performance based

266

INCREASING SCIENTIFIC POWER WITH STATISTICAL POWER  

EPA Science Inventory

A brief survey of basic ideas in statistical power analysis demonstrates the advantages and ease of using power analysis throughout the design, analysis, and interpretation of research. he power of a statistical test is the probability of rejecting the null hypothesis of the test...

267

Dynamic power systems for power generation  

NASA Astrophysics Data System (ADS)

The characteristics of dynamic power systems have considerable potential value, especially for the space station. The base of technology that makes these dynamic power systems practical is reviewed. The following types of power-generating systems are examined herein: organic Rankine cycle, potassium Rankine cycle, Brayton cycle, and Stirling cycle.

English, R. E.

1984-04-01

268

Flow Components in a NaK Test Loop Designed to Simulate Conditions in a Nuclear Surface Power Reactor  

SciTech Connect

A test loop using NaK as the working fluid is presently in use to study material compatibility effects on various components that comprise a possible nuclear reactor design for use on the lunar surface. A DC electromagnetic (EM) pump has been designed and implemented as a means of actively controlling the NaK flow rate through the system and an EM flow sensor is employed to monitor the developed flow rate. These components allow for the matching of the flow rate conditions in test loops with those that would be found in a full-scale surface-power reactor. The design and operating characteristics of the EM pump and flow sensor are presented. In the EM pump, current is applied to a set of electrodes to produce a Lorentz body force in the fluid. A measurement of the induced voltage (back-EMF) in the flow sensor provides the means of monitoring flow rate. Both components are compact, employing high magnetic field strength neodymium magnets thermally coupled to a water-cooled housing. A vacuum gap limits the heat transferred from the high temperature NaK tube to the magnets and a magnetically-permeable material completes the magnetic circuit. The pump is designed to produce a pressure rise of 34.5 kPa, and the flow sensor's predicted output is roughly 20 mV at the loop's nominal flow rate of 0.114 m{sup 3}/hr.

Polzin, Kurt A.; Godfroy, Thomas J. [NASA Marshall Space Flight Center Propulsion Research and Technology Applications Branch/ER24, MSFC, AL 35812 (United States)

2008-01-21

269

The Green Power Network: Buying Green Power  

NSDL National Science Digital Library

The Green Power Network (GPN), operated and maintained by the National Renewable Energy Laboratory for the U.S. Department of Energy, provides news and information on green power markets and related activities. Here, they supply a great tool for discovering green power availability throughout the United States. Clicking on any state will provide visitors with any green power including utility green pricing programs, retail green power products offered in competitive utility markets, and renewable energy certificate products (REC) sold separate from electricity. This will be a useful tool for instructors or students interested in renewable energy technologies.

2008-10-21

270

Infrared power cells for satellite power conversion  

NASA Technical Reports Server (NTRS)

An analytical investigation is performed to assess the feasibility of long-wavelength power converters for the direct conversion of IR radiation onto electrical power. Because theses devices need to operate between 5 and 30 um the only material system possible for this application is the HgCdTe system which is currently being developed for IR detectors. Thus solar cell and IR detector theories and technologies are combined. The following subject areas are covered: electronic and optical properties of HgCdTe alloys; optimum device geometry; junction theory; model calculation for homojunction power cell efficiency; and calculation for HgCdTe power cell and power beaming.

Summers, Christopher J.

1991-01-01

271

Evolution of Carbide Precipitates in 2.25Cr-1Mo Steel during Long-Term Service in a Power Plant  

NASA Astrophysics Data System (ADS)

Carbide precipitation from the steel matrix during long-term high-temperature exposure can adversely affect the fracture toughness and high-temperature creep resistance of materials with implications on the performance of power plant components. In the present work, carbide evolution in 2.25Cr-1Mo steel after long-term aging during service was investigated. Boiler pipe samples of this steel were removed from a supercritical water-cooled coal-fired power plant after service times of 17 and 28 years and a mean operational temperature of 810 K (537 C). The carbide precipitation and coarsening effects were studied using the carbon extraction replica technique followed by analysis using transmission electron microscopy and energy dispersive X-ray spectroscopy. The carbides extracted using an electrolytic technique were also analyzed using X-ray diffraction to evaluate phase transformations of the carbides during long-term service. Small ball punch and Vickers hardness were used to evaluate the changes in mechanical performance after long-term aging during service.

Yang, Yong; Chen, Yiren; Sridharan, Kumar; Allen, Todd R.

2010-03-01

272

Performance of the 10kV, 100-kA pulsed-power modules for the FRX-C magnetic compression experiment  

SciTech Connect

In this paper, we present detailed performance data collected from over a year's operation of the 25 and 50-kJoule pulsed-power capacitor-bank modules developed for the Los Alamos magnetic fusion facility FRX-C. These modules supply the 5-MA magnet current needed for the compressional heating of compact toroid plasmoids. To date, 54 modules have been built and successfully tested at their full design rating: 100-kA peak output current at 10-kV charge, {tau}{sub 1/4} = 60 {mu}s (25-kJ module), or 110 {mu}s (50-kJ module), crowbar L/R {le} 1 ms. Modules are compact, cost about $5000 each, and though designed for 25 or 50 kJ, they can be easily modified for other pulsed-power applications. Energy is stored in 25-kJ capacitors. Start and crowbar switching is performed with a pair of water-cooled, size-D ignitrons. As an alternative to an ignitron, crowbar switching by solid-state rectifiers has been successfully demonstrated. Current is conducted between components and to the load by parallel-plate transmission lines and by a parallel array of commercially-available coaxial cable. 4 refs., 8 figs.

Rej, D.J.; Waganaar, W.J. (Los Alamos National Lab., NM (USA))

1989-01-01

273

Nuclear analyses of supercritical water cooled reactor with carbon nano-tube cladding  

SciTech Connect

The authors have confirmed the feasibility of the dual layer clad comprised of iron and carbon nano-tube to problems of Super Critical Water Reactor cores. Continuous energy Monte Carlo method was applied. The difference between JENDL-3.3 and ENDF-6 was confirmed. Depletion was carried out. (authors)

Uenohara, Y. [Independent and Personal Activity, 1-15-H106, Higashi-Terao, Tsurumi-ku, Yokohama 230-0077 (Japan); Yamano, N. [Research Inst. of Nuclear Engineering, Univ. of Fukui, 3-9-1, Bunkyo, Fukui 910-8507 (Japan)

2012-07-01

274

NUCLEAR CHEMISTRY OF WATER-COOLED FUSION REACTORS: ISSUES AND SOLUTIONS  

SciTech Connect

ITER is an experimental Tokamak fusion energy reactor that is being built in Cadarache, France, in collaboration with seven agencies representing China, the European Union, India, Japan, Republic of Korea, the Russian Federation, and the United States. The main objective of ITER is to demonstrate the scientific and technical feasibility of a controlled fusion reaction An important U.S. contribution is the design, fabrication, and delivery of the Tokamak Cooling Water System (TCWS). This paper describes the main sources of radioactivity in TCWS water, which are the nitrogen isotopes 16N and 17N, tritium, activated corrosion products, and the carbon isotope 14C; the relative contribution of each of these sources to the total radioactive contamination of water; issues related to excess accumulation of these species; and methods to control TCWS radioactivity within acceptable limits. Among these methods are: (1) water purification to minimize corrosion of materials in contact with TCWS water; (2) monitoring of vital chemistry parameters and control of water chemistry; (3) design of proper building structure and/or TCWS loop/geometry configuration; and (4) design of an ITER liquid radwaste facility tailored to TCWS operational requirements. Design of TCWS nuclear chemistry control is crucial to ensuring that the inventory of radioactive species is consistent with the principle of 'As Low as Reasonably Achievable.'

Petrov, Andrei Y [ORNL] [ORNL; Flanagan, George F [ORNL] [ORNL

2010-01-01

275

Wear of water-cooled mandrels in alloy-steel piercing  

Microsoft Academic Search

In operation, piercing mandrels are heated to high temperatures and experience considerable pressures. The mandrel life depends on numerous factors, such as the chemical composition and heat treatment of the metal; the calibration of the mandrel; the type of steel being worked; the temperature of the blank prior to piercing; the machine time in rolling; the adjustment of the piercing

N. M. Vavilkin; V. S. Goncharov; D. V. Bodrov; S. V. Lipnyagov

2009-01-01

276

Numerical Investigation of Liquid Water Cooling for a Proton Exchange Membrane Fuel Cell Stack  

Microsoft Academic Search

The operation of proton exchange membrane fuel cell (PEMFC) stacks requires careful thermal and water management for optimal performance. Appropriate placement of cooling plates and appropriate cooling conditions are therefore essential. To study the impact of these design parameters, a two-phase model accounting for the conservation of mass, momentum, species, energy, and charge, a phenomenological model for the membrane, and

Agus P. Sasmito; Erik Birgersson; Arun S. Mujumdar

2011-01-01

277

Two-point boundary temperature control of hot strip via water cooling  

Microsoft Academic Search

This paper presents a two-point boundary temperature control system approach, for Run Out Table (ROT) cooling, used in hot strip mills. The system relies on a linearized model for describing heat radiated to the environment and heat transferred to cooling water. A basic feedforward control design to control the temperature at the second boundary point, the only measurable controlled parameter,

Nicholas S. Samaras; Marwan A. Simaan

1997-01-01

278

Holonic control of a water cooling system for a steel rod mill  

Microsoft Academic Search

As part of the intelligent manufacturing systems feasibility study on holonic manufacturing systems, a benchmark study whose objective was to develop an architecture of a holonic cooling control system for a steel rod rolling mill is described. The resulting architecture was simulated to illustrate benefits that could be obtained with the holonic system compared with a conventional system. A generic

J. R. Agre; G. Elsley; D. McFarlane; J. Cheng; B. Gunn

1994-01-01

279

MODELING THE NUKIYAMA CURVE FOR WATER-COOLED FUSION DIVERTOR CHANNELS  

Microsoft Academic Search

A conclusive safety assessment of a fusion reactor requires that the thermal response of the divertor assembly is known with a high degree of accuracy. Such accuracy is mandated because the divertor assembly is subjected to the highest levels of incident heat flux within the reactor. In order to accurately predict the thermal response of the divertor's cooling channels, it

Theron D. Marshall; Dennis L. Youchison; Lee C. Cadwallader

280

Water-cooled end-point boundary temperature control of hot strip via dynamic programming  

Microsoft Academic Search

In this paper, an end-point boundary temperature control approach for runout table cooling used in hot strip mills is presented. The system relies on a linearized model for describing heat radiated to the environment and heat transferred to cooling water. At first, a conventional feedforward control design to control the temperature at the end-point boundary, the only measurable controlled parameter,

Nicholas S. Samaras; Marwan A. Simaan

1998-01-01

281

A water-cooled spherical niobium target for the production of [ 18F]fluoride  

Microsoft Academic Search

A new automated target system for the routine production of [18F]fluoride from 18O-enriched water has been constructed. It consists of a small spherical niobium target chamber mounted into a special holder, which provides rapid cooling by water flow around the sphere. The target is irradiated with 21 MeV protons; the incident energy in the target chamber is 13 MeV. The

S. K. Zeisler; D. W. Becker; R. A. Pavan; R. Moschel; H. Rhle

2000-01-01

282

Impact of different moderator ratios with light and heavy water cooled reactors in equilibrium states  

Microsoft Academic Search

As an issue of sustainable development in the world, energy sustainability using nuclear energy may be possible using several different ways such as increasing breeding capability of the reactors and optimizing the fuel utilization using spent fuel after reprocessing as well as exploring additional nuclear resources from sea water. In this present study the characteristics of light and heavy water

Sidik Permana; Naoyuki Takaki; Hiroshi Sekimoto

2006-01-01

283

Effects of Water Radiolysis in Water Cooled Reactors - Nuclear Energy Research Initiative (NERI) Program  

SciTech Connect

OAK B188 Quarterly Progress Report on NERI Proposal No.99-0010 for the Development of an Experiment and Calculation Based Model to Describe the Effects of Radiation on Non-standard Aqueous Systems Like Those Encountered in the Advanced Light Water Reactor

S. M. Pimblott

2000-10-01

284

In pursuit of non-phosphorus corrosion inhibitors for cold water cooling systems  

SciTech Connect

An exploratory program was conducted to evaluate a number of polymers and carboxylic acid combinations with polymers as non-phosphorus containing, all organic corrosion inhibitors for cold water systems such as evaporative towers. The concentrations of treatment were approximately those which would obtain for current commercial formulations. There was a strong dependency of performance on the aggressiveness of the water, especially the conductivity. The polymers were adequate for non-aggressive waters, and one, polymaleic acid (as the sodium salt) performed reasonably in somewhat more corrosive systems. Certain alkenyl substituted dibasic acids were also found to perform well in the less challenging waters as did simpler dibasic materials such as maleic, fumaric and aspartic acids. A tetrabasic acid with the carboxyl groups located in proximity to each other, BTA, in combination with certain, but, not all, polymers showed considerable promise.

Wyman, D.P. [Rochester Midland Corp., NY (United States). Unytex Research Div.

1998-12-31

285

Design of 95 GHz gyrotron based on continuous operation copper solenoid with water cooling  

NASA Astrophysics Data System (ADS)

The design work for 2nd harmonic 95 GHz, 50 kW gyrotron based on continuous operation copper solenoid is presented. Thermionic magnetron injection gun specifications were calculated according to the linear trade off equation, and simulated with CST program. Numerical code is used for cavity design using the non-uniform string equation as well as particle motion in the "cold" cavity field. The mode TE02 with low Ohmic losses in the cavity walls was chosen as the operating mode. The Solenoid is designed to induce magnetic field of 1.8 T over a length of 40 mm in the interaction region with homogeneity of 0.34%. The solenoid has six concentric cylindrical segments (and two correction segments) of copper foil windings separated by water channels for cooling. The predicted temperature in continuous operation is below 93 C. The parameters of the design together with simulation results of the electromagnetic cavity field, magnetic field, electron trajectories, and thermal analyses are presented.

Borodin, Dmitri; Ben-Moshe, Roey; Einat, Moshe

2014-07-01

286

R and D on a Supercritical Pressure Water-Cooled Reactor in Korea  

SciTech Connect

Korea is actively participating in the international collaboration program on the development of a SCWR with Canada, Japan, EU, France, and USA. In this paper the current progress of the research activities on the SCWR in Korea is presented. The current research areas include reactor core conceptual design, a heat transfer test with supercritical CO{sub 2}, an improvement of existing safety analysis code adapting to supercritical pressure condition, and an evaluation and/or development of candidate material. (authors)

Bae, Yoon-Yeong; Bae, Kang-Mok; Yoon, Han-Young; Kim, Hyungrae; Hwang, Seong-Sik [Korea Atomic Energy Research Institute, 150 Deokjin Yuseong Daejeon (Korea, Republic of)

2006-07-01

287

Apparatus and method of direct water cooling several parallel circuit cards each containing several chip packages  

DOEpatents

A cooling apparatus, system and like method for an electronic device includes a plurality of heat producing electronic devices affixed to a wiring substrate. A plurality of heat transfer assemblies each include heat spreaders and thermally communicate with the heat producing electronic devices for transferring heat from the heat producing electronic devices to the heat transfer assemblies. The plurality of heat producing electronic devices and respective heat transfer assemblies are positioned on the wiring substrate having the regions overlapping. A heat conduit thermally communicates with the heat transfer assemblies. The heat conduit circulates thermally conductive fluid therethrough in a closed loop for transferring heat to the fluid from the heat transfer assemblies via the heat spreader. A thermally conductive support structure supports the heat conduit and thermally communicates with the heat transfer assemblies via the heat spreader transferring heat to the fluid of the heat conduit from the support structure.

Cipolla, Thomas M. (Katonah, NY); Colgan, Evan George (Chestnut Ridge, NY); Coteus, Paul W. (Yorktown Heights, NY); Hall, Shawn Anthony (Pleasantville, NY); Tian, Shurong (Mount Kisco, NY)

2011-12-20

288

Oxidation of Zircaloy Fuel Cladding in Water-Cooled Nuclear Reactors  

SciTech Connect

Our work involved the continued development of the theory of passivity and passivity breakdown, in the form of the Point Defect Model, with emphasis on zirconium and zirconium alloys in reactor coolant environments, the measurement of critically-important parameters, and the development of a code that can be used by reactor operators to actively manage the accumulation of corrosion damage to the fuel cladding and other components in the heat transport circuits in both BWRs and PWRs. In addition, the modified boiling crevice model has been further developed to describe the accumulation of solutes in porous deposits (CRUD) on fuel under boiling (BWRs) and nucleate boiling (PWRs) conditions, in order to accurately describe the environment that is contact with the Zircaloy cladding. In the current report, we have derived expressions for the total steady-state current density and the partial anodic and cathodic current densities to establish a deterministic basis for describing Zircaloy oxidation. The models are deterministic because the relevant natural laws are satisfied explicitly, most importantly the conversation of mass and charge and the equivalence of mass and charge (Faradays law). Cathodic reactions (oxygen reduction and hydrogen evolution) are also included in the models, because there is evidence that they control the rate of the overall passive film formation process. Under open circuit conditions, the cathodic reactions, which must occur at the same rate as the zirconium oxidation reaction, are instrumental in determining the corrosion potential and hence the thickness of the barrier and outer layers of the passive film. Controlled hydrodynamic methods have been used to measure important parameters in the modified Point Defect Model (PDM), which is now being used to describe the growth and breakdown of the passive film on zirconium and on Zircaloy fuel sheathing in BWRs and PWRs coolant environments. The modified PDMs recognize the existence of a thick oxide outer layer over a thin barrier layer. From thermodynamic analysis, it is postulated that a hydride barrier layer forms under PWR coolant conditions whereas an oxide barrier layer forms under BWR primary coolant conditions. Thus, the introduction of hydrogen into the solution lowers the corrosion potential of zirconium to the extent that the formation of ZrH2 is predicted to be spontaneous rather than the ZrO2. Mott-Schottky analysis shows that the passive film formed on zirconium is n-type, which is consistent with the PDM, corresponding to a preponderance of oxygen/hydrogen vacancies and/or zirconium interstitials in the barrier layer. The model parameter values were extracted from electrochemical impedance spectroscopic data for zirconium in high temperature, de-aerated and hydrogenated environments by optimization. The results indicate that the corrosion resistance of zirconium is dominated by the porosity and thickness of the outer layer for both cases. The impedance model based on the PDM provides a good account of the growth of the bi-layer passive films described above, and the extracted model parameter values might be used, for example, for predicting the accumulation of general corrosion damage to Zircaloy fuel sheath in BWR and PWR operating environments. Transients in current density and film thickness for passive film formation on zirconium in dearated and hydrogenated coolant conditions have confirmed that the rate law afforded by the Point Defect Model (PDM) adequately describes the growth and thinning of the passive film. The experimental results demonstrate that the kinetics of oxygen or hydrogen vacancy generation at the metal/film interface control the rate of film growth, when the potential is displaced in the positive direction, whereas the kinetics of dissolution of the barrier layer at the barrier layer/solution interface control the rate of passive film thinning when the potential is stepped in the negative direction. In addition, the effects of second phase particles (SPPs) on the electrochemistry of passive zirconium in the

Digby Macdonald; Mirna Urquidi-Macdonald; Yingzi Chen; Jiahe Ai; Pilyeon Park; Han-Sang Kim

2006-12-12

289

Maximum Power Point  

NSDL National Science Digital Library

Students learn how to find the maximum power point (MPP) of a photovoltaic (PV) panel in order to optimize its efficiency at creating solar power. They also learn about real-world applications and technologies that use this technique, as well as Ohm's law and the power equation, which govern a PV panel's ability to produce power.

Integrated Teaching And Learning Program

290

Wind Power Now!  

ERIC Educational Resources Information Center

The government promotes and heavily subsidizes research in nuclear power plants. Federal development of wind power is slow in comparison even though much research with large wind-electric machines has already been conducted. Unless wind power programs are accelerated it will not become a major energy alternative to nuclear power. (MR)

Inglis, David Rittenhouse

1975-01-01

291

Power Series Introduction  

E-print Network

Power Series 16.4 Introduction In this section we consider power series. These are examples of infinite series where each term contains a variable, x, raised to a positive integer power. We use the ratio test to obtain the radius of convergence R, of the power series and state the important result

Vickers, James

292

Photovoltaic solar power systems  

Microsoft Academic Search

An introduction into photovoltaic device theory and design is given to provide a background for discussing applications for solar power system. The potential for using silicon solar cells to provide large amounts of electrical power is shown and a proposed plan for developing solar power systems for a wide range of applications is described. Solar power systems utilized in remote

E. L. Ralph

1974-01-01

293

Nuclear power: Fourth edition  

Microsoft Academic Search

This book describes the basics of nuclear power generation, explaining both the benefits and the real and imagined risks of nuclear power. It includes a discussion of the Three Mile Island accident and its effects. Nuclear Power has been used in the public information programs of more than 100 utilities. The contents discussed are: Nuclear Power and People; Why Nuclear

Deutsch

1986-01-01

294

Miners lamp power pack  

SciTech Connect

A lamp rechargeable dry cell power pack and recharging device therefor is disclosed. The recharging device comprises a socket for receiving the power pack, a plurality of electrodes are presented in the socket and arranged to contact corresponding electrodes on the power pack when it is fully inserted in the socket. The power pack is irregular shaped in cross-section and the socket is correspondingly shaped to receive and support the power pack in only one orientation of the power pack relative to the socket to ensure the registration of the plurality of socket electrodes with corresponding power pack electrodes.

Lane, K.S.

1984-11-06

295

HIGH-POWER LITHIUM TARGET FOR ACCELERATOR-BASED BNCT  

Microsoft Academic Search

A water-cooled conical target for producing neutrons via the 7 Li(p,n) 7 Be reaction at 2.5 MeV is under development at Linac Systems. The target is intended to accept an expanded 50-kW beam from an rf linac, and is predicted to meet the intensity requirements for practical accelerator-based boron neutron capture therapy (BNCT) in concert with Linac Systems' CW RFI

Carl Willis; John Lenz; Donald Swenson

296

Mobile Uninterruptible Power Supply  

NASA Technical Reports Server (NTRS)

Proposed mobile unit provides 20 kVA of uninterruptible power. Used with mobile secondary power-distribution centers to provide power to test equipment with minimal cabling, hazards, and obstacles. Wheeled close to test equipment and system being tested so only short cable connections needed. Quickly moved and set up in new location. Uninterruptible power supply intended for tests which data lost or equipment damaged during even transient power failure.

Mears, Robert L.

1990-01-01

297

IXYS Power MOSFET Products  

Microsoft Academic Search

This paper presents IXYS Corporation's power MOSFET products and their typical application information. Power MOSFETs are widely used in power switching applications due to their features of easy control, fast switching speed, wide safe operating area and high gain. Typical applications include Switched-Mode Power Supply (SMPS), DC-DC Converters and DC-AC Inverters for Motor Controls, High-Frequency Pulse Power Supplies (commonly called

Abdus Sattar

298

HVDC Thyristor Valve Development  

Microsoft Academic Search

The development of the thyristor valve technology from the first designed air-cooled thyristor valve to the modern water-cooled thyristor valve is described. The design and design criteria for the modern water-cooled valve are briefly described. The performance of the previous air-cooled design and the water-cooled design is compared especially with regard to power handling capability including overload capacity, power losses,

Ake Ekstrom; Lars Eklund

1987-01-01

299

The power of PowerPoint.  

PubMed

Carousel slide presentations have been used for academic and clinical presentations since the late 1950s. However, advances in computer technology have caused a paradigm shift, and digital presentations are quickly becoming standard for clinical presentations. The advantages of digital presentations include cost savings; portability; easy updating capability; Internet access; multimedia functions, such as animation, pictures, video, and sound; and customization to augment audience interest and attention. Microsoft PowerPoint has emerged as the most popular digital presentation software and is currently used by many practitioners with and without significant computer expertise. The user-friendly platform of PowerPoint enables even the novice presenter to incorporate digital presentations into his or her profession. PowerPoint offers many advanced options that, with a minimal investment of time, can be used to create more interactive and professional presentations for lectures, patient education, and marketing. Examples of advanced PowerPoint applications are presented in a stepwise manner to unveil the full power of PowerPoint. By incorporating these techniques, medical practitioners can easily personalize, customize, and enhance their PowerPoint presentations. Complications, pitfalls, and caveats are discussed to detour and prevent misadventures in digital presentations. Relevant Web sites are listed to further update, customize, and communicate PowerPoint techniques. PMID:11496193

Niamtu, J

2001-08-01

300

High power fast ramping power supplies  

SciTech Connect

Hundred megawatt level fast ramping power converters to drive proton and heavy ion machines are under research and development at accelerator facilities in the world. This is a leading edge technology. There are several topologies to achieve this power level. Their advantages and related issues will be discussed.

Marneris,I.; Bajon, E.; Bonati, R.; Sandberg, J.; Roser, T.; Tsoupas, N.

2009-05-04

301

Power the world's powers the world's economy.  

E-print Network

Power the world's economy #12;powers the world's economy. Put yourself in the driver's seat-in entrepreneurship and business incubator can put you on the road to an exciting future. #12;Careers setting up shop With a career in business, you can apply creativity, problem solving and leadership to support a strong economy

Escher, Christine

302

Space nuclear power systems  

NASA Technical Reports Server (NTRS)

Space nuclear power systems are considered for use in those particular spacecraft applications for which nuclear power systems offer unique advantages over solar and/or chemical space power systems. Both isotopic and reactor heated space electrical power units are described in an attempt to illustrate their operating characteristics, spacecraft integration aspects, and factory-to-end of mission operational considerations. The status of technology developments in nuclear power systems is presented. Some projections of those technologies are made to form a basis for the applications of space nuclear power systems to be expected over the next 10-15 years.

Carpenter, R. T.

1972-01-01

303

An Innovative System for the Efficient and Effective Treatment of Non-Traditional Waters for Reuse in Thermoelectric Power Generation  

SciTech Connect

This study assessed opportunities for improving water quality associated with coal-fired power generation including the use of non-traditional waters for cooling, innovative technology for recovering and reusing water within power plants, novel approaches for the removal of trace inorganic compounds from ash pond effluents, and novel approaches for removing biocides from cooling tower blowdown. This research evaluated specifically designed pilot-scale constructed wetland systems for treatment of targeted constituents in non-traditional waters for reuse in thermoelectric power generation and other purposes. The overall objective of this project was to decrease targeted constituents in non-traditional waters to achieve reuse criteria or discharge limitations established by the National Pollutant Discharge Elimination System (NPDES) and Clean Water Act (CWA). The six original project objectives were completed, and results are presented in this final technical report. These objectives included identification of targeted constituents for treatment in four non-traditional water sources, determination of reuse or discharge criteria for treatment, design of constructed wetland treatment systems for these non-traditional waters, and measurement of treatment of targeted constituents in non-traditional waters, as well as determination of the suitability of the treated non-traditional waters for reuse or discharge to receiving aquatic systems. The four non-traditional waters used to accomplish these objectives were ash basin water, cooling water, flue gas desulfurization (FGD) water, and produced water. The contaminants of concern identified in ash basin waters were arsenic, chromium, copper, mercury, selenium, and zinc. Contaminants of concern in cooling waters included free oxidants (chlorine, bromine, and peroxides), copper, lead, zinc, pH, and total dissolved solids. FGD waters contained contaminants of concern including arsenic, boron, chlorides, selenium, mercury, chemical oxygen demand (COD), and zinc. Similar to FGD waters, produced waters contained contaminants of concern that are predominantly inorganic (arsenic, cadmium, chlorides, chromium, copper, lead, mercury, nickel, sulfide, zinc, total dissolved solids), but also contained some organics (benzene, PAHs, toluene, total organic carbon, total suspended solids, and oil and grease). Constituents of concern that may cause chemical scaling, biofouling and corrosion, such as pH, hardness and ionic strength, and nutrients (P, K, and N) may also be found in all four non-traditional waters. NPDES permits were obtained for these non-traditional waters and these permit limits are summarized in tabular format within this report. These limits were used to establish treatment goals for this research along with toxicity values for Ceriodaphnia dubia, water quality criteria established by the US EPA, irrigation standards established by the United States Department of Agriculture (USDA), and reuse standards focused on minimization of damage to the power plant by treated waters. Constructed wetland treatment systems were designed for each non-traditional water source based on published literature reviews regarding remediation of the constituents of concern, biogeochemistry of the specific contaminants, and previous research. During this study, 4 non-traditional waters, which included ash basin water, cooling water, FGD water and produced water (PW) were obtained or simulated to measure constructed wetland treatment system performance. Based on data collected from FGD experiments, pilot-scale constructed wetland treatment systems can decrease aqueous concentrations of elements of concern (As, B, Hg, N, and Se). Percent removal was specific for each element, including ranges of 40.1% to 77.7% for As, 77.6% to 97.8% for Hg, 43.9% to 88.8% for N, and no measureable removal to 84.6% for Se. Other constituents of interest in final outflow samples should have aqueous characteristics sufficient for discharge, with the exception of chlorides (<2000 mg/L). Based on total dissolved solids, co-

John Rodgers; James Castle

2008-08-31

304

Power beaming providing a space power infrastructure  

SciTech Connect

This study, based on two levels of technology, applies the power beaming concept to four planned satellite constellations. The analysis shows that with currently available technology, power beaming can provide mass savings to constellations in orbits ranging from low earth orbit to geosynchronous orbit. Two constellations, space surveillance and tracking system and space based radar, can be supported with current technology. The other two constellations, space-based laser array and boost surveillance and tracking system, will require power and transmission system improvements before their breakeven specific mass is achieved. A doubling of SP-100 conversion efficiency from 10 to 20/% would meet or exceed breakeven for these constellations.

Bamberger, J.A.; Coomes, E.P.

1992-08-01

305

Savings Through Power Quality  

E-print Network

Incidents of problems and damage to customerowned electrical equipment and machinery resulting from abnormal voltage conditions, current imbalance, surges/transients, harmonics, losses, power factor, power interruptions, and phase loss...

Mehrdad, M.

2005-01-01

306

Body powered thermoelectric systems  

E-print Network

Great interest exists for and progress has be made in the effective utilization of the human body as a possible power supply in hopes of powering such applications as sensors and continuously monitoring medical devices ...

Settaluri, Krishna Tej

2012-01-01

307

Smart Power Grid  

NSDL National Science Digital Library

This video segment adapted from NOVA scienceNOW provides an overview of the existing United States power grid, and envisions a smart power grid that would prevent problems, such as blackouts, and reduce energy waste and pollution.

WGBH Educational Foundation

2011-03-31

308

Technologies. [space power sources  

NASA Technical Reports Server (NTRS)

Energy technologies to meet the power requirements of future space missions are reviewed. Photovoltaic, solar dynamic, and solar thermal technologies are discussed along with techniques for energy storage and power management and distribution.

Brandhorst, Henry W., Jr.

1992-01-01

309

Strategic Power Infrastructure Defense  

Microsoft Academic Search

This paper provides a comprehensive state-of-the-art overview on power infrastructure defense systems. A review of the literature on the subjects of critical infrastructures, threats to the power grids, defense system concepts, and the special protection systems is reported. The proposed Strategic Power Infrastructure Defense (SPID) system methodology is a real-time, wide-area, adaptive protection and control system involving the power, communication,

Hao Li; GARY W. ROSENWALD; JUHWAN JUNG; Chen-ching Liu

2005-01-01

310

Power of Points  

NSDL National Science Digital Library

This geometry lesson introduces the Power of Points theorem. While it is often taught in three parts (the Chord-Chord Power theorem, the Secant-Secant Power theorem, and the Tangent-secant Power theorem), this lesson demonstrates how the three theorems relate to one another. An interactive applet is included to help demonstrate the theorem. This activity is best for grades 9-12 and should require 1 class period to complete.

2011-01-17

311

Trace-element characterization of evidential cannabis sative samples using k{sub 0}-standardization methodology  

SciTech Connect

The University of Florida Training Reactor (UFTR) facilities including the analytical laboratory are used for a wide range of educational, research, training, and service functions. The UFTR is a 100-kW light-water-cooled, graphite-and-water-moderated modified Argonaut-type reactor. The UFTR utilizes high enriched plate-type fuel in a two-slab arrangement and operates at a 100-kW power level. Since first licensed to operate at 10 kW in 1959, this nonpower reactor facility has had an active but evolving record of continuous service to a wide range of academic, utility, and community users. The services of the UFTR have also been used by various state authorities in criminal investigations. Because of its relatively low power and careful laboratory analyses, the UFTR neutron flux characteristics in several ports are not only well characterized but they are also quite invariant with time. As a result, such a facility is well-suited to the application of the multielement analysis using the k{sub o}-standardization method of neutron activation analysis. The analysis of untreated evidential botanical samples presented a unique opportunity to demonstrate implementation of this method at the UFTR facilities.

Henderson, D.P. Jr.; Vernetson, W.G.; Ratner, R.T. [Univ. of Florida, Gainesville, FL (United States)] [and others

1995-12-31

312

Comparative Assessment of Gasification Based Coal Power Plants with Various CO2 Capture Technologies Producing Electricity and Hydrogen  

PubMed Central

Seven different types of gasification-based coal conversion processes for producing mainly electricity and in some cases hydrogen (H2), with and without carbon dioxide (CO2) capture, were compared on a consistent basis through simulation studies. The flowsheet for each process was developed in a chemical process simulation tool Aspen Plus. The pressure swing adsorption (PSA), physical absorption (Selexol), and chemical looping combustion (CLC) technologies were separately analyzed for processes with CO2 capture. The performances of the above three capture technologies were compared with respect to energetic and exergetic efficiencies, and the level of CO2 emission. The effect of air separation unit (ASU) and gas turbine (GT) integration on the power output of all the CO2 capture cases is assessed. Sensitivity analysis was carried out for the CLC process (electricity-only case) to examine the effect of temperature and water-cooling of the air reactor on the overall efficiency of the process. The results show that, when only electricity production in considered, the case using CLC technology has an electrical efficiency 1.3% and 2.3% higher than the PSA and Selexol based cases, respectively. The CLC based process achieves an overall CO2 capture efficiency of 99.9% in contrast to 89.9% for PSA and 93.5% for Selexol based processes. The overall efficiency of the CLC case for combined electricity and H2 production is marginally higher (by 0.3%) than Selexol and lower (by 0.6%) than PSA cases. The integration between the ASU and GT units benefits all three technologies in terms of electrical efficiency. Furthermore, our results suggest that it is favorable to operate the air reactor of the CLC process at higher temperatures with excess air supply in order to achieve higher power efficiency. PMID:24578590

2014-01-01

313

Solar lunar power  

NASA Technical Reports Server (NTRS)

Current and projected technology is assessed for photovoltaic power for a lunar base. The following topics are discussed: requirements for power during the lunar day and night; solar cell efficiencies, specific power, temperature sensitivity, and availability; storage options for the lunar night; array and system integration; the potential for in situ production of photovoltaic arrays and storage medium.

Bailey, Sheila G.; Landis, Geoffrey A.

1994-01-01

314

Bottle Rock Power Corporation  

E-print Network

Bottle Rock Power Corporation 1275 4th Street, No. 105 Phone: 707.541.0976 Santa Rosa, CA 95404 Fax 1516 9th Street, MS-2000 Sacramento, CA 95814-5512 RE: Bottle Rock Power Plant (79-AFC-4C) Petition for Extending Environmental Monitoring Program Dear Ms. Tronaas: The Bottle Rock Power Corporation (BRPC

315

Solar powered desalination system  

E-print Network

efficiency for a PV system is a ratio of the electrical power output to the solarSolar Energy Calculator using Google Maps 23 Table 1.24: PV System Power Production Average Daily Irradiance (kWh/m2) Instillation Efficiencysolar-to-hydrogen (STH) conversion efficiency is 10%. (STH conversion efficiency is power

Mateo, Tiffany Alisa

2011-01-01

316

Aircraft Electric Secondary Power  

NASA Technical Reports Server (NTRS)

Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

1983-01-01

317

Optimal Power Flow Solutions  

Microsoft Academic Search

A practical method is given for solving the power flow problem with control variables such as real and reactive power and transformer ratios automatically adjusted to minimize instantaneous costs or losses. The solution is feasible with respect to constraints on control variables and dependent variables such as load voltages, reactive sources, and tie line power angles. The method is based

Hermann Dommel; William Tinney

1968-01-01

318

Fluid Power Technician  

ERIC Educational Resources Information Center

Fluid power technicians, sometimes called hydraulic and pneumatic technicians, work with equipment that utilizes the pressure of a liquid or gas in a closed container to transmit, multiply, or control power. Working under the supervision of an engineer or engineering staff, they assemble, install, maintain, and test fluid power equipment.

Moore, Pam

2008-01-01

319

Power Plant Cycling Costs  

SciTech Connect

This report provides a detailed review of the most up to date data available on power plant cycling costs. The primary objective of this report is to increase awareness of power plant cycling cost, the use of these costs in renewable integration studies and to stimulate debate between policymakers, system dispatchers, plant personnel and power utilities.

Kumar, N.; Besuner, P.; Lefton, S.; Agan, D.; Hilleman, D.

2012-07-01

320

Decentralizing hydro power production  

Microsoft Academic Search

We analyse the production of electricity from n power stations in a dynamic model. Each power station's production of electricity is constrained by the quantity of water available to it (supply constraint) as well as limitations on reservoir capacity (storage constraint). We show that hydro power production can lead to two sources of welfare loss: suboptimal management of water resources

Stefan Ambec; Joseph A. Doucet

2003-01-01

321

Geothermal Power Plant Model  

NSDL National Science Digital Library

In this activity, learners make a model of a power plant that uses steam. Learners use simple materials like foil, a tin can, and a pot of water to model a geothermal power plant. Learners use a pinwheel to observe the power produced by the steam. SAFETY NOTE: Adult assistance required.

Commission, California E.

2006-01-01

322

Nuclear Power Plant Accidents  

MedlinePLUS

... that is contaminated. People living close to the nuclear power plant who are exposed to radiation could experience long-term health effects such as ... from the power company that operates your local nuclear power plant or your local emergency services ... INSIDE STAY TUNED http://emergency.cdc.gov/radiation

323

Power delivery system  

Microsoft Academic Search

This patent describes a power delivery system for connecting a transmission to an output shaft of an engine, the transmission including a dog clutch for establishing a power transmission route by the engagement of the dog clutch, the power delivery system comprising; a clutch for disconnecting the engagement between an output member of the fluid coupling and the output shaft

S. Moroto; S. Sakakibara

1987-01-01

324

The Administrative Power Grab  

ERIC Educational Resources Information Center

Administrative power for some school teachers can be an aphrodisiac that can be applied negatively, especially when a leader has devastating instinct for the weaknesses of others. A leader's intellect and heart closes shop and ceases to function when drunk on power. In this article, the author describes how the use of administrative power can be

Sorenson, Richard D.

2007-01-01

325

Power quality following deregulation  

Microsoft Academic Search

Utility deregulation will have tangible and intangible effects on power quality requiring industry-wide action to maintain adequate standards. These effects are discussed in the first part of the paper. The increasing trend towards more extensive use of power electronic control at the generation, transmission and utilization systems following deregulation has power quality implications that will affect the standards, system simulation

JOS ARRILLAGA; MATH H. J. BOLLEN; NEVILLE R. WATSON

2000-01-01

326

Flexible Power Electronic Transformer  

Microsoft Academic Search

This paper proposes a new modular flexible power electronic transformer (FPET). The proposed FPET is flexible enough to meet future needs of power electronic centralized systems. The main feature of the FPET is the independent operation of modules each of which contains one port. Each port can be considered as input or output, because bidirectional power flow is provided. The

Mehran Sabahi; Ali Yazdanpanah Goharrizi; Seyed Hossein Hosseini; Mohammad Bagher Bana Sharifian; Gevorg B. Gharehpetian

2010-01-01

327

ADEPT: Efficient Power Conversion  

SciTech Connect

ADEPT Project: In todays increasingly electrified world, power conversionthe process of converting electricity between different currents, voltage levels, and frequenciesforms a vital link between the electronic devices we use every day and the sources of power required to run them. The 14 projects that make up ARPA-Es ADEPT Project, short for Agile Delivery of Electrical Power Technology, are paving the way for more energy efficient power conversion and advancing the basic building blocks of power conversion: circuits, transistors, inductors, transformers, and capacitors.

None

2011-01-01

328

Multimegawatt space power reactors  

SciTech Connect

In response to the need of the Strategic Defense Initiative (SDI) and long range space exploration and extra-terrestrial basing by the National Air and Space Administration (NASA), concepts for nuclear power systems in the multi-megawatt levels are being designed and evaluated. The requirements for these power systems are being driven primarily by the need to minimize weight and maximize safety and reliability. This paper will discuss the present requirements for space based advanced power systems, technological issues associated with the development of these advanced nuclear power systems, and some of the concepts proposed for generating large amounts of power in space. 31 figs.

Dearien, J.A.; Whitbeck, J.F.

1989-01-01

329

International Space Station Power Systems  

NASA Technical Reports Server (NTRS)

This viewgraph presentation gives a general overview of the International Space Station Power Systems. The topics include: 1) The Basics of Power; 2) Space Power Systems Design Constraints; 3) Solar Photovoltaic Power Systems; 4) Energy Storage for Space Power Systems; 5) Challenges of Operating Power Systems in Earth Orbit; 6) and International Space Station Electrical Power System.

Propp, Timothy William

2001-01-01

330

Multimode power processor  

DOEpatents

In one embodiment, a power processor which operates in three modes: an inverter mode wherein power is delivered from a battery to an AC power grid or load; a battery charger mode wherein the battery is charged by a generator; and a parallel mode wherein the generator supplies power to the AC power grid or load in parallel with the battery. In the parallel mode, the system adapts to arbitrary non-linear loads. The power processor may operate on a per-phase basis wherein the load may be synthetically transferred from one phase to another by way of a bumpless transfer which causes no interruption of power to the load when transferring energy sources. Voltage transients and frequency transients delivered to the load when switching between the generator and battery sources are minimized, thereby providing an uninterruptible power supply. The power processor may be used as part of a hybrid electrical power source system which may contain, in one embodiment, a photovoltaic array, diesel engine, and battery power sources.

O'Sullivan, George A. (Pottersville, NJ); O'Sullivan, Joseph A. (St. Louis, MO)

1999-01-01

331

Multimode power processor  

DOEpatents

In one embodiment, a power processor which operates in three modes: an inverter mode wherein power is delivered from a battery to an AC power grid or load; a battery charger mode wherein the battery is charged by a generator; and a parallel mode wherein the generator supplies power to the AC power grid or load in parallel with the battery. In the parallel mode, the system adapts to arbitrary non-linear loads. The power processor may operate on a per-phase basis wherein the load may be synthetically transferred from one phase to another by way of a bumpless transfer which causes no interruption of power to the load when transferring energy sources. Voltage transients and frequency transients delivered to the load when switching between the generator and battery sources are minimized, thereby providing an uninterruptible power supply. The power processor may be used as part of a hybrid electrical power source system which may contain, in one embodiment, a photovoltaic array, diesel engine, and battery power sources. 31 figs.

O'Sullivan, G.A.; O'Sullivan, J.A.

1999-07-27

332

Power flow for spacecraft power systems  

NASA Technical Reports Server (NTRS)

A method for constructing the generalized system-level admittance matrix for use with a Newton-Raphson power flow is presented. The network modeling technique presented does not use the standard pi-equivalent models, which assume a lossless return path, for the transmission line and transformer. If the return path cannot be assumed lossless, then the standard algorithms for constructing the system admittance matrix cannot be used. The method presented here uses concepts from linear graph theory to combine network modules to form the system-level admittance matrix. The modeling technique is presented, and the resulting matrix is used with a standard Newton-Raphson power flow to calculate all system voltages and current (power) flows.

Halpin, S. M.; Grigsby, L. L.; Sheble, G. B.; Nelms, R. M.

1989-01-01

333

Sixth Power Plan northwest Power and Conservation Council  

E-print Network

Sixth Power Plan northwest Power and Conservation Council March 15, 2013 Mid-term assessment Summary #12;PaGe 2 > Mid-TerM AssessMenT suMMAry > Sixth Power Plan topics · Background on the Council · Northwest Power System · Sixth Northwest Power Plan · Mid-Term Assessment · Seventh Northwest Power Plan

334

POWER SYSTEMS STABILITY WITH LARGE-SCALE WIND POWER PENETRATION  

E-print Network

generation which may lead to power system control problems. Therefore, adequate models of an Automatic Automatic Generation Control, Power Balancing, Power System Stability, Frequency Stability, and Wind Power 1 of an Automatic Generation Control (AGC) system, wind farms, conventional power plants and Combined Heat and Power

Bak-Jensen, Birgitte

335

Peak power ratio generator  

DOEpatents

A peak power ratio generator is described for measuring, in combination with a conventional power meter, the peak power level of extremely narrow pulses in the gigahertz radio frequency bands. The present invention in a preferred embodiment utilizes a tunnel diode and a back diode combination in a detector circuit as the only high speed elements. The high speed tunnel diode provides a bistable signal and serves as a memory device of the input pulses for the remaining, slower components. A hybrid digital and analog loop maintains the peak power level of a reference channel at a known amount. Thus, by measuring the average power levels of the reference signal and the source signal, the peak power level of the source signal can be determined.

Moyer, Robert D. (Albuquerque, NM)

1985-01-01

336

Power Subscription Strategy.  

SciTech Connect

This document lays out the Bonneville Power Administration`s ``Power Subscription Strategy,`` a process that will enable the people of the Pacific Northwest to share the benefits of the Federal Columbia river Power System after 2001 while retaining those benefits within the region for future generations. The strategy also addresses how those who receive the benefits of the region`s low-cost federal power should share a corresponding measure of the risks. This strategy seeks to implement the subscription concept created by the Comprehensive Review in 1996 through contracts for the sale of power and the distribution of federal power benefits in the deregulated wholesale electricity market. The success of the subscription process is fundamental to BPA`s overall business purpose to provide public benefits to the Northwest through commercially successful businesses.

United States. Bonneville Power Administration.

1998-12-21

337

Fluid Power Basics  

NSDL National Science Digital Library

Students learn about the fundamental concepts important to fluid power, which includes both pneumatic (gas) and hydraulic (liquid) systems. Both systems contain four basic components: reservoir/receiver, pump/compressor, valve, cylinder. Students learn background information about fluid powerboth pneumatic and hydraulic systemsincluding everyday applications in our world (bulldozers, front-end loaders, excavators, chair height lever adjustors, door closer dampers, dental drills, vehicle brakes) and related natural laws. After a few simple teacher demos, they learn about the four components in all fluid power systems, watch two 26-minute online videos about fluid power, complete a crossword puzzle of fluid power terms, and conduct a task card exercise. This prepares them to conduct the associated hands-on activity, using the Portable Fluid Power Demonstrator (teacher-prepared kits) to learn more about the properties of gases and liquids in addition to how forces are transmitted and multiplied within these systems.

2014-09-18

338

Fusion Engineering and Design 48 (2000) 371378 Blanket system selection for the ARIES-ST  

E-print Network

likely be a water- cooled Cu magnet. Therefore, the design of the power plant has to be compatible) is to investigate the attractiveness of a low-aspect-device as the confinement concept for a fusion power plant is a water-cooled Cu normal conductor. This selection has a major impact on the blanket design and selection

California at San Diego, University of

339

10 CFR Appendix I to Part 50 - Numerical Guides for Design Objectives and Limiting Conditions for Operation To Meet the...  

Code of Federal Regulations, 2010 CFR

...Light-Water-Cooled Nuclear Power Reactor...Part 50 Energy NUCLEAR REGULATORY...materials in the environment and in the...cost-benefit ratio effect reductions...potential for effects from long-term...buildup on the environment in the vicinity...light-water-cooled nuclear power...

2010-01-01

340

Nuclear power browning out  

SciTech Connect

When the sad history of nuclear power is written, April 26, 1986, will be recorded as the day the dream died. The explosion at the Chernobyl plant was a terrible human tragedy- and it delivered a stark verdict on the hope that nuclear power will one day replace fossil fuel-based energy systems. Nuclear advocates may soldier on, but a decade after Chernobyl it is clear that nuclear power is no longer a viable energy option for the twenty-first century.

Flavin, C.; Lenssen, N.

1996-05-01

341

Electric power annual 1993  

SciTech Connect

This report presents a summary of electric power industry statistics at national, regional, and state levels: generating capability and additions, net generation, fossil-fuel statistics, retail sales and revenue, finanical statistics, environmental statistics, power transactions, demand side management, nonutility power producers. Purpose is to provide industry decisionmakers, government policymakers, analysts, and the public with historical data that may be used in understanding US electricity markets.

Not Available

1994-12-08

342

Unified powered flight guidance  

NASA Technical Reports Server (NTRS)

A complete revision of the orbiter powered flight guidance scheme is presented. A unified approach to powered flight guidance was taken to accommodate all phases of exo-atmospheric orbiter powered flight, from ascent through deorbit. The guidance scheme was changed from the previous modified version of the Lambert Aim Point Maneuver Mode used in Apollo to one that employs linear tangent guidance concepts. This document replaces the previous ascent phase equation document.

Brand, T. J.; Brown, D. W.; Higgins, J. P.

1973-01-01

343

NEP power subsystem modeling  

NASA Technical Reports Server (NTRS)

The Nuclear Electric Propulsion (NEP) system optimization code consists of a master module and various submodules. Each of the submodules represents a subsystem within the total NEP power system. The master module sends commands and input data to each of the submodules and receives output data back. Rocketdyne was responsible for preparing submodules for the power conversion (both K-Rankine and Brayton), heat rejection, and power management and distribution.

Harty, Richard B.

1993-01-01

344

Power subsystem automation study  

NASA Technical Reports Server (NTRS)

The purpose of the phase 2 of the power subsystem automation study was to demonstrate the feasibility of using computer software to manage an aspect of the electrical power subsystem on a space station. The state of the art in expert systems software was investigated in this study. This effort resulted in the demonstration of prototype expert system software for managing one aspect of a simulated space station power subsystem.

Tietz, J. C.; Sewy, D.; Pickering, C.; Sauers, R.

1984-01-01

345

NEP power subsystem modeling  

NASA Astrophysics Data System (ADS)

The Nuclear Electric Propulsion (NEP) system optimization code consists of a master module and various submodules. Each of the submodules represents a subsystem within the total NEP power system. The master module sends commands and input data to each of the submodules and receives output data back. Rocketdyne was responsible for preparing submodules for the power conversion (both K-Rankine and Brayton), heat rejection, and power management and distribution.

Harty, Richard B.

346

Space Station Power System  

NASA Technical Reports Server (NTRS)

The strategies, reasoning, and planning guidelines used in the development of the United States Space Station Program are outlined. The power required to support Space Station missions and housekeeping loads is a key driver in overall Space Station design. conversely, Space Station requirements drive the power technology. Various power system technology options are discussed. The mission analysis studies resulting in the required Space Station capabilities are also discussed. An example of Space Station functions and a concept to provide them is presented. The weight, area, payload and altitude requirements on draft and mass requirements are described with a summary and status of key power systems technology requirements and issues.

Baraona, C. R.

1984-01-01

347

Application Power Signature Analysis  

SciTech Connect

The high-performance computing (HPC) community has been greatly concerned about energy efficiency. To address this concern, it is essential to understand and characterize the electrical loads of HPC applications. In this work, we study whether HPC applications can be distinguished by their power-consumption patterns using quantitative measures in an automatic manner. Using a collection of 88 power traces from 4 different systems, we find that basic statistical measures do a surprisingly good job of summarizing applications' distinctive power behavior. Moreover, this study opens up a new area of research in power-aware HPC that has a multitude of potential applications.

Hsu, Chung-Hsing [ORNL] [ORNL; Combs, Jacob [Sonoma State University] [Sonoma State University; Nazor, Jolie [Sonoma State University] [Sonoma State University; Santiago, Fabian [Sonoma State University] [Sonoma State University; Thysell, Rachelle [Sonoma State University] [Sonoma State University; Rivoire, Suzanne [Sonoma State University] [Sonoma State University; Poole, Stephen W [ORNL] [ORNL

2014-01-01

348

Power conversion technologies  

SciTech Connect

The Power Conservation Technologies thrust area supports initiatives that enhance the core competencies of the Lawrence Livermore National Laboratory (LLNL) Engineering Directorate in the area of solid-state power electronics. Through partnerships with LLNL programs, projects focus on the development of enabling technologies for existing and emerging programs that have unique power conversion requirements. This year, a multi-disciplinary effort was supported which demonstrated solid-state, high voltage generation by using a dense, monolithic photovoltaic array. This effort builds upon Engineering's strengths in the core technology areas of power conversion, photonics, and microtechnologies.

Haigh, R E

1998-01-01

349

Residential Wind Power  

E-print Network

renewableenergyworld.com. The AWEA has a lot of useful information on alternative energy sources. The AWEA produces many case studies in which there is abundant wind power to incorporate as a source to the US power grid. It is a conclusion of the AWEA that wind... manufacturers addressing residential wind power. One product that is very prevalent, and a pioneer within the industry, is SkyStream 3.7 produced by Southwest Wind Power. (skystream.com, 2011) This product can range in price based on installation and size...

Willis, Gary

2011-12-16

350

Hybrid Power Management (HPM)  

NASA Technical Reports Server (NTRS)

The NASA Glenn Research Center s Avionics, Power and Communications Branch of the Engineering and Systems Division initiated the Hybrid Power Management (HPM) Program for the GRC Technology Transfer and Partnership Office. HPM is the innovative integration of diverse, state-of-the-art power devices in an optimal configuration for space and terrestrial applications. The appropriate application and control of the various power devices significantly improves overall system performance and efficiency. The advanced power devices include ultracapacitors and fuel cells. HPM has extremely wide potential. Applications include power generation, transportation systems, biotechnology systems, and space power systems. HPM has the potential to significantly alleviate global energy concerns, improve the environment, and stimulate the economy. One of the unique power devices being utilized by HPM for energy storage is the ultracapacitor. An ultracapacitor is an electrochemical energy storage device, which has extremely high volumetric capacitance energy due to high surface area electrodes, and very small electrode separation. Ultracapacitors are a reliable, long life, maintenance free, energy storage system. This flexible operating system can be applied to all power systems to significantly improve system efficiency, reliability, and performance. There are many existing and conceptual applications of HPM.

Eichenberg, Dennis J.

2007-01-01

351

CSTI High Capacity Power  

NASA Technical Reports Server (NTRS)

The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil application. During FY-86 and 87, the NASA SP-100 Advanced Technology Program was devised to maintain the momentum of promising technology advancement efforts started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In FY-88, the Advanced Technology Program was incorporated into NASA's new Civil Space Technology Initiative (CSTI). The CSTI Program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA SP-100 Advanced Technology project, and provides a bridge to NASA Project Pathfinder. The elements of CSTI High Capacity Power development include Conversion Systems, Thermal Management, Power Management, System Diagnostics, and Environmental Interactions. Technology advancement in all areas, including materials, is required to assure the high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems as well as allowing mission independence from solar and orbital attitude requirements. Several recent advancements in CSTI High Capacity power development will be discussed.

Winter, Jerry M.

1989-01-01

352

Power Factor Improvement  

E-print Network

and Dr. Russell Heiser mann, School of Technology, Electrical Power Department. 1032 ESL-IE-79-04-121 Proceedings from the First Industrial Energy Technology Conference Houston, TX, April 22-25, 1979 I 3. Total Olrrent - (apparent power... is the power factor of the load on a 460 volt, 3 phase system if the annneter indicates 110 amperes and the wattmeter reads 60 KW? Since in a 3-phase circuit: KVA = 3 volts' amperes = 1.73 * 460 * 110 87.54 1000 1000 Power factor = ~V = 60 = .685 or 68...

Viljoen, T. A.

1979-01-01

353

CSTI high capacity power  

SciTech Connect

The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil application. During FY86 and 87, the NASA SP-100 Advanced Technology Program was devised to maintain the momentum of promising technology advancement efforts started during Phase I of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In FY88, the Advanced Technology Program was incorporated into NASA`s new Civil Space Technology Initiative (CSTI). The CSTI Program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA SP-100 Advanced Technology project, and provides a bridge to NASA Project Pathfinder. The elements of CSTI High Capacity Power development include Conversion Systems, Thermal Management, Power Management, System Diagnostics, and Environmental Interactions. Technology advancement in all areas, including materials, is required to assure the high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems as well as allowing mission independence from solar and orbital attitude requirements. Several recent advancements in CSTI High Capacity power development will be discussed.

Winter, J.M.

1994-09-01

354

Power beaming options  

NASA Technical Reports Server (NTRS)

Some large scale power beaming applications are proposed for the purpose of stimulating research. The first proposal is for a combination of large phased arrays on the ground near power stations and passive reflectors in geostationary orbit. The systems would beam excess electrical power in microwave form to areas in need of electrical power. Another proposal is to build solar arrays in deserts and beam the energy around the world. Another proposal is to use lasers to beam energy from earth to orbiting spacecraft.

Rather, John D. G.

1989-01-01

355

Efficiency and Power  

NSDL National Science Digital Library

The following animation shows how a load resistance results in increase in output power. Use the up and down arrow keys to change the load resistance. While viewing, note the following: power output peaks when load resistance equals generator resistance, further increases in load resistance results in lower output power. The objective is to describe the optimum load versus power settings for transfer of RF Energy. This simulation is from Module 106 of the RF Energy and Plasma Cluster of the MATEC Module Library (MML).

2011-10-05

356

Reducing electric power transmission losses  

Microsoft Academic Search

The reduction of transmission-related power losses in electric grids has become increasingly important in every phase of power systems concerned with conservation of fuel and power resources. The most effective approaches to the matter of electric power loss reduction in power transmission lines are discussed. These methods include reactive power compensation, both on loads and system substations, optimization of grid

A. I. Kulchitskii; S. P. Elagina

1982-01-01

357

Automated Power-Distribution System  

NASA Technical Reports Server (NTRS)

Autonomous power-distribution system includes power-control equipment and automation equipment. System automatically schedules connection of power to loads and reconfigures itself when it detects fault. Potential terrestrial applications include optimization of consumption of power in homes, power supplies for autonomous land vehicles and vessels, and power supplies for automated industrial processes.

Ashworth, Barry; Riedesel, Joel; Myers, Chris; Miller, William; Jones, Ellen F.; Freeman, Kenneth; Walsh, Richard; Walls, Bryan K.; Weeks, David J.; Bechtel, Robert T.

1992-01-01

358

Potassium Rankine power system for space power  

NASA Astrophysics Data System (ADS)

A review of the proposed concepts for multimegawatt (MMW) power levels in Strategic Defense Initiative applications was completed. A trade study format was used to evaluate currently proposed MMW ALERT mode concepts to determine which of these concepts could best meet the program requirements for steady-state and burst MMW power levels in Category 2. The MMW program's evaluation criteria were applied to each concept to determine its relative ranking within each criteria category. These criteria included the system characteristics related to its safety, reliability, mass, volume/area, technical risk, costs, environmental exposure, and growth potential. Technical feasibility issues associated with the successful development of each concept was also identified. An overall system concept ranking was developed for the four concepts that appeared to best meet the Category 2 MMW program requirements. The in-core thermionic and potassium Rankine power system concepts received the highest relative rankings from this study. The AMTEC and CBC technologies were ranked as distant second and third candidates, respectively. Rocketdyne has selected the potassium Rankine power system concept for additional study based upon its superior growth potential over the in-core thermionic MMW concept.

Baumeister, E. B.; Determan, William R.

359

RACE, POWER, MULTIPOSITIONALITY  

Microsoft Academic Search

To understand the relationship between social position and social change, this essay examines the multipositionality of the black schoolteacher, and through it the relationship between race and power. The autobiographical writings of black teachers who worked in the American South between 1890 and 1950 uniquely reveal the complex relationship between power and culture in this phase of American history, and

Earl Lewis

2008-01-01

360

Automotive Power Trains.  

ERIC Educational Resources Information Center

This correspondence course, originally developed for the Marine Corps, is designed to provide mechanics with an understanding of the operation, maintenance, and troubleshooting of automotive power trains and certain auxiliary equipment. The course contains six study units covering basic power trains; clutch principles and operations; conventional

Marine Corps Inst., Washington, DC.

361

HIDDEN POWER IN MARRIAGE  

Microsoft Academic Search

Without patriarchal laws and legally permitted gender discrimination, it becomes clearer that a powerful draw back to gender equality springs from norms about gender identity, concepts of masculinity and femininity, and tacit rules of interaction between women and men. This article offers a theoretical perspective to analyze hidden power in gender relationships. The conceptualization is based on research into marital

AAFKE KOMTER

1989-01-01

362

Solar Powered Refrigeration System  

NASA Astrophysics Data System (ADS)

A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

Ewert, Michael K.; Bergeron, David J., III

2002-09-01

363

Power System Dynamic Equivalents  

Microsoft Academic Search

This paper describes a method for determining a simplified equivalent mathematical representation of portions of a power system for transient stability analysis. The method leads to equations that do not correspond directly to a system composed of normal power system components. Conditions under which it is possible to obtain such an equivalent are given, and the results of applying the

Albert Chang; Mahmood Adibi

1970-01-01

364

Explorations in Statistics: Power  

ERIC Educational Resources Information Center

Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This fifth installment of "Explorations in Statistics" revisits power, a concept fundamental to the test of a null hypothesis. Power is the probability that we reject the null hypothesis when it is false. Four things affect

Curran-Everett, Douglas

2010-01-01

365

Solar Powered Refrigeration System  

NASA Technical Reports Server (NTRS)

A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

2002-01-01

366

NUCLEAR POWER in CALIFORNIA  

E-print Network

NUCLEAR POWER in CALIFORNIA: 2007 STATUS REPORT CALIFORNIA ENERGY COMMISSION October 2007 CEC-100, California Contract No. 700-05-002 Prepared For: California Energy Commission Barbara Byron, Senior Nuclear public workshops on nuclear power. The Integrated Energy Policy Report Committee, led by Commissioners

367

Multimegawatt space power reactors  

Microsoft Academic Search

In response to the need of the Strategic Defense Initiative (SDI) and long range space exploration and extra-terrestrial basing by the National Air and Space Administration (NASA), concepts for nuclear power systems in the multi-megawatt levels are being designed and evaluated. The requirements for these power systems are being driven primarily by the need to minimize weight and maximize safety

J. A. Dearien; J. F. Whitbeck

1989-01-01

368

Power from Ocean Waves.  

ERIC Educational Resources Information Center

Discussed is the utilization of surface ocean waves as a potential source of power. Simple and large-scale wave power devices and conversion systems are described. Alternative utilizations, environmental impacts, and future prospects of this alternative energy source are detailed. (BT)

Newman, J. N.

1979-01-01

369

Hydrothermal Power Systems  

NSDL National Science Digital Library

This web site by the Department of Energy (DOE) covers geothermal power plants by using text and diagrams. The website describes the three kinds of plants and provides photographs of each. The page also gives information on the future of geothermal energy and also provides links to geothermal power plants across the US.

2007-07-20

370

Power Station Design  

NASA Technical Reports Server (NTRS)

Kuljian Corporation provides design engineering and construction management services for power generating plants in more than 20 countries. They used WASP (Calculating Water and Steam Properties), a COSMIC program to optimize power station design. This enabled the company to substantially reduce lead time and software cost in a recent design project.

1985-01-01

371

Talk About Nuclear Power  

ERIC Educational Resources Information Center

Presents an overview of the relation of nuclear power to human health and the environment, and discusses the advantages and disadvantages of nuclear power as an energy source urging technical educators to inculcate an awareness of the problems associated with the production of energy. Describes the fission reaction process, the hazards of

Tremlett, Lewis

1976-01-01

372

Nuclear Power Plants. Revised.  

ERIC Educational Resources Information Center

This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Among the topics discussed are: Why Use Nuclear Power?; From Atoms to Electricity; Reactor Types; Typical Plant Design Features; The Cost of Nuclear Power; Plants in the United States; Developments in Foreign

Lyerly, Ray L.; Mitchell, Walter, III

373

Competing with nuclear power  

Microsoft Academic Search

Cogeneration and small power production must compete with other energy sources, particularly the nuclear power industry, if it is to survive and prosper. The author examines cogeneration's ability to compete against operating nuclear plants and those which are under construction. He emphasizes the opportunity for rate incentives provided by the Public Utility Regulatory Policies Act and the costs of liability

Spiewak

1986-01-01

374

Power and Economics.  

ERIC Educational Resources Information Center

Discusses whether the United States possesses sufficient international power to (1) shape its own destiny in the current world economic climate, and (2) influence significantly and constructively the destiny of the world economy as a whole. Argues that the key to America's future economic power lies in ideas and concepts. (Author/GC)

Rostow, W. W.

1981-01-01

375

Wind Power Animation  

NSDL National Science Digital Library

This animation, from the US Department of Energy, discusses the advantages of wind power, the workings of a wind turbine, and wind resources in the United States. It also describes how wind power is used in small- and large-scale applications.

US Department of Energy; Energy Efficiency and Renewable Energy (EERE)

376

Power, Media & Montesquieu. New forms of public power and the balance of power  

E-print Network

SUMMARY Power, Media & Montesquieu. New forms of public power and the balance of power are organized it is crucial to restrain the power that the state exerts on its citizens. The state has three functions, commonly known as powers: the legislative, executive and judicial powers. This three

van den Brink, Jeroen

377

Power module assembly  

DOEpatents

A power module assembly of the type suitable for deployment in a vehicular power inverter, wherein the power inverter has a grounded chassis, is provided. The power module assembly comprises a conductive base layer electrically coupled to the chassis, an insulating layer disposed on the conductive base layer, a first conductive node disposed on the insulating layer, a second conductive node disposed on the insulating layer, wherein the first and second conductive nodes are electrically isolated from each other. The power module assembly also comprises a first capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the first conductive node, and further comprises a second capacitor having a first electrode electrically connected to the conductive base layer, and a second electrode electrically connected to the second conductive node.

Campbell, Jeremy B. (Torrance, CA); Newson, Steve (Redondo Beach, CA)

2011-11-15

378

Power supply conditioning circuit  

NASA Technical Reports Server (NTRS)

A power supply conditioning circuit that can reduce Periodic and Random Deviations (PARD) on the output voltages of dc power supplies to -150 dBV from dc to several KHz with no measurable periodic deviations is described. The PARD for a typical commercial low noise power supply is -74 dBV for frequencies above 20 Hz and is often much worse at frequencies below 20 Hz. The power supply conditioning circuit described here relies on the large differences in the dynamic impedances of a constant current diode and a zener diode to establish a dc voltage with low PARD. Power supplies with low PARD are especially important in circuitry involving ultrastable frequencies for the Deep Space Network.

Primas, L. E.; Loveland, R.

1987-01-01

379

Space Nuclear Power Systems  

NASA Technical Reports Server (NTRS)

Fission power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system.

Houts, Michael G.

2012-01-01

380

PASSIVE CONTROL OF FLUID POWERED HUMAN POWER AMPLIFIERS  

E-print Network

PASSIVE CONTROL OF FLUID POWERED HUMAN POWER AMPLIFIERS Perry Y. Li and Venkat Durbha Center is proposed for the control of fluid powered human power amplifiers. Human power amplifiers are mechanical tools that humans operate directly and the human force is amplified hydraulically or pneumatically

Li, Perry Y.

381

The Green Power Network: Green Power government information clearinghouse  

NSDL National Science Digital Library

This site contains Green Power information from the Energy Efficiency and Renewable Energy Clearinghouse of the U.S. Department of Energy. The Green Power Network exists to provide "news and information on green power providers." The site's information is searchable by state and shows different markets for green power (utility green pricing, green power marketing, and renewable energy certificates).

2008-08-26

382

Northwest Power and Conservation Council Fifth Northwest Power Plan  

E-print Network

Northwest Power and Conservation Council Fifth Northwest Power Plan Statement of Basis and Purpose for the Fifth Power Plan and Response to Comments on the Draft Fifth Power Plan February 2005 #12;I. Background.........................................................................................................................................3 B. Developing the Fifth Power Plan

383

FUTURE POWER GRID INITIATIVE GridOPTICSTM Power Networking,  

E-print Network

FUTURE POWER GRID INITIATIVE GridOPTICSTM Power Networking, Equipment, and Technology (powerNET) Testbed OBJECTIVE A lot of interest in research, improvements, and testing surrounds the power grid to these activities. Specifically, » power system equipment is expensive and has a high knowledge barrier

384

Design of Power Supply for Driving High Power Piezoelectric Actuators  

E-print Network

Design of Power Supply for Driving High Power Piezoelectric Actuators Rongyuan Li, Michael and power density, they are applied more and more in aircrafts and industry. These actuators are normally focus on the power supply and its control architecture for driving high power piezoelectric actuators

Paderborn, Universität

385

Power Consumption Prediction and Power-Aware Packing in Consolidated  

E-print Network

Power Consumption Prediction and Power-Aware Packing in Consolidated Environments Jeonghwan Choi the power consumption of groups of colocated applications. Such characterization is crucial for effective prediction and enforcement of appropriate limits on power consumption--power budgets--within the data center

Urgaonkar, Bhuvan

386

The Power of Non-Uniform Wireless Power  

E-print Network

The Power of Non-Uniform Wireless Power ETH Zurich ­ Distributed Computing Group Magnus M-To-Interference-Plus-Noise Ratio (SINR) Formula Minimum signal- to-interference ratio Power level of sender u Path-loss exponent Noise Distance between two nodes Received signal power from sender Received signal power from all other

387

Nanosatellite Power System Considerations  

NASA Technical Reports Server (NTRS)

The capability to build complex electronic functions into compact packages is opening the path to miniature satellites on the order of 1 kg mass, 10 cm across, packed with the computing processors, motion controllers, measurement sensors, and communications hardware necessary for operation. Power generation will be from short strings of silicon or gallium arsenide-based solar photovoltaic cells with the array power maximized by a peak power tracker (PPT). Energy storage will utilize a low voltage battery with nickel cadmium or lithium ion cells as the most likely selections for rechargeables and lithium (MnO2-Li) primary batteries for one shot short missions.

Robyn, M.; Thaller, L.; Scott, D.

1995-01-01

388

Power Systems Decentralized Optimization  

NASA Astrophysics Data System (ADS)

The paper's aim is to explore both active and reactive power losses minimization and voltage stability by a decentralized strategy. The approach assumes that the grid is split into sub-systems; each sub-system is in charge of its own optimal solution using equivalents for the neighbors, so that information exchange is not required. Schedule interchanges among sub-systems have been added as constraints into the optimal formulation. Once the individual solutions are available, the corresponding settings are allocated to the corresponding equipment and a full power flow study is carried out to assure the steady-state preservation. Results are exhibited on two test power systems.

Ramirez, Juan M.; Vargas-Marn, Javier; Correa-Gutirrez, Rosa E.

2014-12-01

389

Foucault's Ethics of Power  

E-print Network

Foucault's Ethics of Power Kirk Wolf Delia College 1. I n t r o d u c t i o n Since Foucaull 's death in 19K4, his interpreters have generally located his importance in his genealogical critiques and in his phi losophy ofpower. On the one hand... critiques and his views on power remains a matter of dispute, for Foucault neither expressly states a program of critique, nor clearly articulates an account of power. The pur pose of this paper, then, is to establish the relationship between...

Wolf, Kirk

390

TROPIX Power System Architecture  

NASA Technical Reports Server (NTRS)

This document contains results obtained in the process of performing a power system definition study of the TROPIX power management and distribution system (PMAD). Requirements derived from the PMADs interaction with other spacecraft systems are discussed first. Since the design is dependent on the performance of the photovoltaics, there is a comprehensive discussion of the appropriate models for cells and arrays. A trade study of the array operating voltage and its effect on array bus mass is also presented. A system architecture is developed which makes use of a combination of high efficiency switching power convertors and analog regulators. Mass and volume estimates are presented for all subsystems.

Manner, David B.; Hickman, J. Mark

1995-01-01

391

Solar power station  

SciTech Connect

Solar power station with semiconductor solar cells for generating electric power is described, wherein the semiconductor solar cells are provided on a member such as a balloon or a kite which carries the solar cells into the air. The function of the balloon or kite can also be fulfilled by a glider or airship. The solar power station can be operated by allowing the system to ascend at sunrise and descend at sunset or when the wind is going to be too strong in order to avoid any demage.

Wenzel, J.

1982-11-30

392

Rotorcraft contingency power study  

NASA Technical Reports Server (NTRS)

Twin helicopter engines are often sized by the power requirement of a safe mission completion after the failure of one of the two engines. This study was undertaken for NASA Lewis by General Electric Co. to evaluate the merits of special design features to provide a 2-1/2 Contingency Power rating, permitting an engine size reduction. The merits of water injection, turbine cooling airflow modulation, throttle push, and a propellant auxiliary power plant were evaluated using military Life Cycle Cost (LCC) and commercial helicopter Direct Operating Cost (DOC) merit factors in a rubber engine and a rubber aircraft scenario.

Hirschkron, R.; Haynes, J. F.; Goldstein, D. N.; Davis, R. H.

1984-01-01

393

AC power system breadboard  

NASA Technical Reports Server (NTRS)

The object of this program was to design, build, test, and deliver a high-frequency (20-kHz) Power System Breadboard which would electrically approximate a pair of dual redundant power channels of an IOC Space Station. This report describes that program, including the technical background, and discusses the results, showing that the major assumptions about the characteristics of this class of hardware (size, mass, efficiency, control, etc.) were substantially correct. This testbed equipment has been completed and delivered to LeRC, where it is operating as a part of the Space Station Power System Test Facility.

Wappes, Loran J.; Sundberg, R.; Mildice, J.; Peterson, D.; Hushing, S.

1987-01-01

394

Fundamentals of Power Plants  

NSDL National Science Digital Library

This site has information regarding the U.S. Armyâs requirements for the construction and performance of aircraft power plants, brought to you by GlobalSecurity.org. The basic requirements, including reliability, durability, and ease of maintenance are each clearly and succinctly defined. Along with labeled images of aircraft power plants, policy descriptions of the required fuels, combustion, lubrication, and bearings are provided. This would be a helpful tool for students studying aircraft power plant technology, especially those heading into government military service, to gain an understanding of the Armyâs requirements for this aircraft component.

2007-02-18

395

Power control system and method  

DOEpatents

A power system includes an energy harvesting device, a battery coupled to the energy harvesting device, and a circuit coupled to the energy harvesting device and the battery. The circuit is adapted to deliver power to a load by providing power generated by the energy harvesting device to the load without delivering excess power to the battery and to supplement the power generated by the energy harvesting device with power from the battery if the power generated by the energy harvesting device is insufficient to fully power the load. A method of operating the power system is also provided.

Steigerwald, Robert Louis (Burnt Hills, NY) [Burnt Hills, NY; Anderson, Todd Alan (Niskayuna, NY) [Niskayuna, NY

2008-02-19

396

POWER CENTRALIZED SEMIGROUPS PRIMOZ MORAVEC  

E-print Network

POWER CENTRALIZED SEMIGROUPS PRIMOZ MORAVEC Abstract. A semigroup is said to be power centralized if for every pair of elements x and y there exists a power of x commuting with y. The structure of power centralized groups and semigroups is investigated. In particular, we characterize 0-simple power centralized

397

Nano-Power Africa Nano-Power Africa  

E-print Network

Nano-Power Africa i Nano-Power Africa 2 Year Project Implementation Plan Technologies The University of Cape Town, South Africa Haramaya University, Ethiopia Kigali Institute of Technology, Rwanda http://www.eng.uc.edu/~gbeaucag/NanoPowerAfrica

Beaucage, Gregory

398

NIOSH Power Tools Database  

MedlinePLUS

... Search Tool Type: Manufacturer: Technical Specifications: Power Tools Database Choose one of the tools below to view sound specifications. Disclaimer: The NIOSH database does not include a comprehensive list of manufacturers ...

399

Glucose-powered neuroelectronics  

E-print Network

A holy grail of bioelectronics is to engineer biologically implantable systems that can be embedded without disturbing their local environments, while harvesting from their surroundings all of the power they require. As ...

Rapoport, Benjamin Isaac

2011-01-01

400

Magnetohydrodynamic power generation  

NASA Technical Reports Server (NTRS)

Magnetohydrodynamic (MHD) Power Generation is a concise summary of MHD theory, history, and future trends. Results of the major international MHD research projects are discussed. Data from MHD research is included. Economics of initial and operating costs are considered.

Smith, J. L.

1984-01-01

401

How Hydroelectric Power Works  

NSDL National Science Digital Library

This 2-minute YouTube video guides viewers through how hydroelectric power works with Niagara Falls as an example. Animations supplement an explanation for specifics of physical processes involved in energy generation.

Ontario Power Generation

402

Power conversion technologies  

SciTech Connect

The Power Conversion Technologies thrust area identifies and sponsors development activities that enhance the capabilities of engineering at Lawrence Livermore National Laboratory (LLNL) in the area of solid- state power electronics. Our primary objective is to be a resource to existing and emerging LLNL programs that require advanced solid-state power electronic technologies.. Our focus is on developing and integrating technologies that will significantly impact the capability, size, cost, and reliability of future power electronic systems. During FY-96, we concentrated our research efforts on the areas of (1) Micropower Impulse Radar (MIR); (2) novel solid-state opening switches; (3) advanced modulator technology for accelerators; (4) compact accelerators; and (5) compact pulse generators.

Newton, M. A.

1997-02-01

403

Contemporary Power Supplies  

NSDL National Science Digital Library

Created by Work-Ready Electronics, a project of the Advanced Technological Education program, this module walks visitors through the basics of contemporary power supplies. The content of the site is divided into seven areas: contemporary power supply technology, SMPS technology, architecture and operation, discrete devices and SMPS performance, improving efficiency, power supply architectures, power management and digital control in SMPS. There is a quiz for each in the Knowledge Probe area, and the Learning Resources section contains two activities to help cement student understanding. There are also further resources - both print and Web based - for more information and two Questors, a Flash trivia game. The Notebook function allows visitors to take notes and review them at any time. This is an excellent resource students and educators in electronics technician programs.

404

Solar Thermal Power Technologies  

NSDL National Science Digital Library

Published in July 2002 by the Energy Research Foundation of the Netherlands, this 50-page report describes current and future Solar Thermal Power technologies. It offers a unique perspective by looking ahead to the "global energy supply and demand until 2100." Five main technologies are described, and two are examined in depth. The first is a solar tower design that uses a large array of mirrors to reflect all sunlight to a receiver at the top of a tower, and then generates electricity from a steam-powered turbine. SNAP technology is the second focus; this kind of power plant directs artificially created wind down a large tube, turning turbines as the wind escapes. A short history of each of these methods is included, as well as an analysis of world solar power potential.

Groenendaal, B. J.

2002-01-01

405

Mesofluidic magnetohydrodynamic power generation  

E-print Network

Much of the previous research into magnetohydrodynamics has involved large-scale systems. This thesis explores the miniaturization and use of devices to convert the power dissipated within an expanding gas flow into ...

Fucetola, Jay J

2012-01-01

406

Robin Teigland Dominic Power  

E-print Network

and Dominic Power 2013 Individual chapters© Respective authors 2013 All rights reserved. No reproduction, copy-1-137-28301-6 This book is printed on paper suitable for recycling and made from fully managed and sustained forest

Brody, James P.

407

Solar power roof shingle  

NASA Technical Reports Server (NTRS)

Silicon solar cell module provides both all-weather protection and electrical power. Module consists of array of circular silicon solar cells bonded to fiberglass substrate roof shingle with fluorinated ethylene propylene encapsulant.

Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G.

1975-01-01

408

Structural power flow measurement  

SciTech Connect

Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

Falter, K.J.; Keltie, R.F.

1988-12-01

409

Air & Space Power Course  

NSDL National Science Digital Library

While Alfred Thayer Mahan may have been obsessed with the role of naval power in warfare, the 20th century saw the rise of air and space power in a way that might have surprised even Mahan himself. Persons with an interest in the history of air and space power in the United States will definitely appreciate this interactive online course, which was created by the United States Air Force. After completing a free registration form, visitors can go through modules that deal with airpower theory, the foundations of airpower doctrine, and some of the deviations from airpower doctrine that occurred from 1947 to 1986. Some of the material offered here may be most relevant to those serving in the Air Force, but as the site notes "Air and space power enthusiasts of all persuasions are welcomed".

2007-07-15

410

PowerPC News  

NSDL National Science Digital Library

PowerPC News: Full text of an independent electronic magazine published every two weeks for users and developers who want the latest news about the IBM/Motorola/Apple microprocessor family and the systems.

411

Geothermal power generation  

SciTech Connect

The Southern California Edison Co. geothermal program is described in general. The individual power plant projects are described: Brawley 10 MW, Heber 45 MW and Salton Sea 9 MW. Related geothermal activities are mentioned.

Crane, G.K.

1981-01-01

412

Power Quality Implications  

E-print Network

Electric utilities in the United States spend in excess of one billion dollars annually to maintain or improve the quality of electric power supplied to their customers. Yet, an increasing and alarming number of complaints are being voiced...

Hilson, D.

413

Explorations in statistics: power  

NSDL National Science Digital Library

Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This fifth installment of Explorations in Statistics revisits power, a concept fundamental to the test of a null hypothesis. Power is the probability that we reject the null hypothesis when it is false. Four things affect power: the probability with which we are willing to rejectby mistakea true null hypothesis, the magnitude of the difference we want to be able to detect, the variability of the underlying population, and the number of observations in our sample. In an application to an Institutional Animal Care and Use Committee or to the National Institutes of Health, we define power to justify the sample size we propose.

Douglas Curran-Everett (University of Colorado Physiology and Biophysics)

2010-06-01

414

Power plant releasing smoke  

NSDL National Science Digital Library

Power plants are a well-known source of pollution. They drain directly into bodies of water such as the ocean. In addition, they burn fossil fuels to create energy. The smoke that results causes acid rain and global warming.

Katie Hale (California State University, Fullerton;Student, Biological Sciences)

2007-01-12

415

Power subsystem automation study  

NASA Technical Reports Server (NTRS)

Generic power-system elements and their potential faults are identified. Automation functions and their resulting benefits are defined and automation functions between power subsystem, central spacecraft computer, and ground flight-support personnel are partitioned. All automation activities were categorized as data handling, monitoring, routine control, fault handling, planning and operations, or anomaly handling. Incorporation of all these classes of tasks, except for anomaly handling, in power subsystem hardware and software was concluded to be mandatory to meet the design and operational requirements of the space station. The key drivers are long mission lifetime, modular growth, high-performance flexibility, a need to accommodate different electrical user-load equipment, onorbit assembly/maintenance/servicing, and potentially large number of power subsystem components. A significant effort in algorithm development and validation is essential in meeting the 1987 technology readiness date for the space station.

Imamura, M. S.; Moser, R. L.; Veatch, M.

1983-01-01

416

Power conditioning techniques  

NASA Technical Reports Server (NTRS)

The technological developments required to reduce the electrical power system component weights from the state-of-the-art 2.0 kg/kW to the range of 0.1 to 0.2 kg/kW are discussed. Power level requirements and their trends in aerospace applications are identified and presented. The projected weight and launch costs for a 1MW power converter built using state-of-the-art technology are established to illustrate the need for reliable, ultralightweight advanced power components. The key factors affecting converter weight are given and some of the tradeoffs between component ratings and circuit topology are identified. The weight and launch costs for a 1MW converter using 0.1 kg/kW technology are presented. Finally, the objectives and goals of the Multi-Megawatt Program at the NASA Lewis Research Center, which is funded by the SDIO through the Air Force, are given.

Baumann, E. D.

1989-01-01

417

Spring Concert Power Points  

NSDL National Science Digital Library

Students will be able to learn and better understand the lyrics of their concert songs by creating a visual representation of the song. This project is for you to pick 2 of our 6 concert songs and create a power point. Remember in this power point project to try not to use any words. You want to represent the lyrics using only pictures. You do not have to create a ...

Ribera, Mr.

2010-05-10

418

Reactive power compensator  

DOEpatents

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation.

El-Sharkawi, Mohamed A. (Renton, WA); Venkata, Subrahmanyam S. (Woodinville, WA); Chen, Mingliang (Kirkland, WA); Andexler, George (Everett, WA); Huang, Tony (Seattle, WA)

1992-01-01

419

Reactive Power Compensator.  

DOEpatents

A system and method for determining and providing reactive power compensation for an inductive load. A reactive power compensator (50,50') monitors the voltage and current flowing through each of three distribution lines (52a, 52b, 52c), which are supplying three-phase power to one or more inductive loads. Using signals indicative of the current on each of these lines when the voltage waveform on the line crosses zero, the reactive power compensator determines a reactive power compensator capacitance that must be connected to the lines to maintain a desired VAR level, power factor, or line voltage. Alternatively, an operator can manually select a specific capacitance for connection to each line, or the capacitance can be selected based on a time schedule. The reactive power compensator produces control signals, which are coupled through optical fibers (102/106) to a switch driver (110, 110') to select specific compensation capacitors (112) for connections to each line. The switch driver develops triggering signals that are supplied to a plurality of series-connected solid state switches (350), which control charge current in one direction in respect to ground for each compensation capacitor. During each cycle, current flows from ground to charge the capacitors as the voltage on the line begins to go negative from its positive peak value. The triggering signals are applied to gate the solid state switches into a conducting state when the potential on the lines and on the capacitors reaches a negative peak value, thereby minimizing both the potential difference and across the charge current through the switches when they begin to conduct. Any harmonic distortion on the potential and current carried by the lines is filtered out from the current and potential signals used by the reactive power compensator so that it does not affect the determination of the required reactive compensation. 26 figs.

El-Sharkawi, M.A.; Venkata, S.S.; Chen, M.; Andexler, G.; Huang, T.

1992-07-28

420

Space Power Engineering Problems  

NASA Astrophysics Data System (ADS)

Development of space power engineering in the first half of XXI century shall be aimed at preventing the forthcoming energy crisis and ecological catastrophes. The problem can be solved through using solar energy being perpetual, endless, and ecologically safe. As of now, issues on the development and employment of solar power stations and its beaming to the ground stations in the SHF band are put on the agenda. The most pressing problem is to develop orbital solar reflectors to illuminate towns in the polar regions, agricultural regions, and areas of processing sea products. Space-based technologies can be used to deal with typhoons, green house effects, and "ozone holes". Recently, large, frameless film structures formed by centrifugal forces offer the promise of structures for orbital power plants, reflectors, and solar sails. A big success is achieved in the development of power generating solar array elements of amorphous silicon. These innovations would make the development of orbital solar power plants dozens of times cheaper. Such solar arrays shall be used in the nearest future on heavy communication satellites and the Earth remote sensing platforms for generation of 140-160 kW at a specific power beyond 300 W/kg. The cargo traffic needed to develop and maintain the orbital power plants and reflector systems could be equipped with solar sails as the future low thrust propulsion. In 2000, the mankind witnessed an unexpected beginning of energy crisis along with strong hydro- meteorological events (typhoons, floods) that shocked the USA, the Western Europe, England, Japan, and other countries. The total damage is estimated as 90 billions of dollars. The mankind is approaching a boundary beyond which its further existence would depend on how people would learn to control weather and use ecologically safe power sources. Space technology base on the research potential accumulated in the previous century could serve for the solution of this problem.

Senkevich, V. P.

2002-01-01

421

Nuclear power in space  

NASA Astrophysics Data System (ADS)

Written and verbal testimony presented before the House Subcommittee on Energy Research and Development is documented. Current research efforts related to space nuclear power are discussed including the SP-100 Space Reactor Program, development of radioisotope thermoelectric generators, and the Advanced Nuclear Systems Program. Funding, research and test facilities, specific space mission requirements, and the comparison of solar and nuclear power systems are addressed. Witnesses included representatives from DOD, NASA, DOE, universities, and private industry.

422

Tokamak fusion power reactors  

Microsoft Academic Search

The major parameters and corresponding economic characteristics of a representative class of commercial Tokamak fusion power reactors are examined as a function of four major design parameters: plasma beta-t, toroidal magnetic field strength, first-wall lifetime, and power output. It is shown that for beta-t greater than or equal to 0.06, the minimum cost of energy is obtained for toroidal field

W. M. Stacey Jr.; M. A. Abdou

1978-01-01

423

Unmanned powered balloons  

NASA Technical Reports Server (NTRS)

In the late 1960's several governmental agencies sponsored efforts to develop unmanned, powered balloon systems for scientific experimentation and military operations. Some of the programs resulted in hardware and limited flight tests; others, to date, have not progressed beyond the paper study stage. Balloon system designs, materials, propulsion units and capabilities are briefly described, and critical problem areas are pointed out which require further study in order to achieve operational powered balloon systems capable of long duration flight at high altitudes.

Korn, A. O.

1975-01-01

424

Federal electric power  

SciTech Connect

Western Area Power Administration in the Department of Energy markets electric power generated by federal hydroelectric dams in 15 central and western states. Western is planning to construct the Craig/Bonanza transmission line and the controversy involves the questioning of Western's role in the project by an investor-owned utility. GAO found no legal basis to question Western's general authority to construct this project.

Not Available

1989-01-01

425

Nuclear Power Plant  

NSDL National Science Digital Library

This lesson introduces students to the basics of nuclear energy production. Topics include radioisotope thermoelectric generators, natural decay of radioactive isotopes, and chain reactions. There is also a discussion of how to control a chain reaction and some concepts of reactor design. The lesson includes an activity in which students operate an online simulation of a nuclear power plant, attempting to keep power output as high as possible without losing control of the reaction.

John Pratte

426

Nuclear power in space  

SciTech Connect

Nuclear reactors have provided energy for satellites-with nearly disastrous results. Now the US government is proposing to build nuclear-powered boosters to launch Star Wars defenses. These authors represent scientific groups that are opposed to the use of nuclear power in near space. The authors feel that the best course for space-borne reactors is to ban them from Earth orbit and use them in deep space.

Aftergood, S. (Federation of American Scientists, Washington, DC (USA)); Hafemeister, D.W. (California Polytechnic State Univ., Pomona (USA)); Prilutsky, O.F.; Rodionov, S.N. (Space Research Inst., Moscow (USSR)); Primack, J.R. (Univ. of California, Santa Cruz (USA))

1991-06-01

427

A power fallacy.  

PubMed

The power fallacy refers to the misconception that what holds on average -across an ensemble of hypothetical experiments- also holds for each case individually. According to the fallacy, high-power experiments always yield more informative data than do low-power experiments. Here we expose the fallacy with concrete examples, demonstrating that a particular outcome from a high-power experiment can be completely uninformative, whereas a particular outcome from a low-power experiment can be highly informative. Although power is useful in planning an experiment, it is less useful-and sometimes even misleading-for making inferences from observed data. To make inferences from data, we recommend the use of likelihood ratios or Bayes factors, which are the extension of likelihood ratios beyond point hypotheses. These methods of inference do not average over hypothetical replications of an experiment, but instead condition on the data that have actually been observed. In this way, likelihood ratios and Bayes factors rationally quantify the evidence that a particular data set provides for or against the null or any other hypothesis. PMID:25271090

Wagenmakers, Eric-Jan; Verhagen, Josine; Ly, Alexander; Bakker, Marjan; Lee, Michael D; Matzke, Dora; Rouder, Jeffrey N; Morey, Richard D

2014-10-01

428

Powering the Future  

NASA Technical Reports Server (NTRS)

Stirling Technology Company (STC) developed the RG-350 convertor using components from separate Goddard Space Center and U.S. Army Natick SBIR contracts. Based on the RG-350, STC commercialized a product line of Stirling cycle generator sets, known as RemoteGen(TM), with power levels ranging from 10We to 3kWe. Under SBIR agreements with Glenn Research Center, the company refined and extended the capabilities of the RemoteGen convertors. They can provide power in remote locations by efficiently producing electricity from multiple-fuel sources, such as propane, alcohol, gasoline, diesel, coal, solar energy, or wood pellets. Utilizing any fuel source that can create heat, RemoteGen enables the choice of the most appropriate fuel source available. The engines operate without friction, wear, or maintenance. These abilities pave the way for self-powered appliances, such as refrigerators and furnaces. Numerous applications for RemoteGen include quiet, pollution-free generators for RVs and yachts, power for cell phone towers remote from the grid, and off-grid residential power variously using propane, ethanol, and solid biomass fuels. One utility and the National Renewable Energy Laboratory are evaluating a solar dish concentrator version with excellent potential for powering remote irrigation pumps.

2002-01-01

429

Low power arcjet performance  

NASA Technical Reports Server (NTRS)

An experimental investigation was performed to evaluate arc jet operation at low power. A standard, 1 kW, constricted arc jet was run using nozzles with three different constrictor diameters. Each nozzle was run over a range of current and mass flow rates to explore stability and performance in the low power engine. A standard pulse-width modulated power processor was modified to accommodate the high operating voltages required under certain conditions. Stable, reliable operation at power levels below 0.5 kW was obtained at efficiencies between 30 and 40 percent. The operating range was found to be somewhat dependent on constrictor geometry at low mass flow rates. Quasi-periodic voltage fluctuations were observed at the low power end of the operating envelope, The nozzle insert geometry was found to have little effect on the performance of the device. The observed performance levels show that specific impulse levels above 350 seconds can be obtained at the 0.5 kW power level.

Curran, Francis M.; Sarmiento, Charles J.

1990-01-01

430

Low power arcjet performance  

NASA Technical Reports Server (NTRS)

An experimental investigation was performed to evaluate arcjet operation at low power. A standard, 1 kW, constricted arcjet was run using nozzles with three different constrictor diameters. Each nozzle was run over a range of current and mass flow rates to explore stability and performance in the low power regime. A standard pulse-width modulated power processor was modified to accommodate the high operating voltages required under certain conditions. Stable, reliable operation at power levels below 0.5 kW was obtained at efficiencies between 30 and 40 percent. The operating range was found to be somewhat dependent on constrictor geometry at low mass flow rates. Quasi-periodic voltage fluctuations were observed at the low power end of the operating envelope. The nozzle insert geometry was found to have little effect on the performance of the device. The observed performance levels show that specific impulse levels above 350 seconds can be obtained at the 0.5 kW power level.

Curran, Francis M.; Sarmiento, Charles J.

1990-01-01

431

Sweden considers wind power  

SciTech Connect

During 1988, Sweden increased its number of wind generating facilities from 13 to 22, reflecting a new attitude toward wind power developing in the country. Last fall, a 750 kW wind turbine installed in the archipelago of Gothenburg was connected to the grid. The turbine is the biggest in use in Sweden, operated and maintained by the local energy authority of Gothenburg. Most turbines being manufactured have a capacity of 20 to 200 kW. The Maglarp turbine in the south of Sweden has a capacity of 3,000 kW, and the Naesudden turbine on an island in the Baltic Sea has 2,000 kW. The two projects are considered experimental by the owner, Vattenfall, the State Power Board. On the basis of energy production, Maglarp may be the largest in the world. Its highest production, 4,400 MWh, was achieved in 1988. In January 1989, the production was 900 MWh, the third highest monthly production so far since September 1983. The State Power Board, the members of the Swedish Power Association, Sydkraft, together with a number of municipal power companies and stations, have formed the Swedish Energy Development Corporation, SWEDCO. One goal for the new corporation is to include wind power in the Swedish energy system. SWEDCO will provide economic and operation data to pursue wind technology.

Baurrau, P.

1989-09-01

432

Power transaction issues in deregulated power systems  

E-print Network

are the elements of the bus admittance matrix Y, ?, of the system. Where, the Y?, 's - the diagonal ennies ? are equal to the sum of the admittances of all lines and transformers connecting bus j to all other buses including the ground. And, the Y?. 's ? the off...-diagonal entries - are equal to the negatives of the admittances of lines between bus i and bus j. Yij's are equal to zero if bus i and bus j are not connected. Hence, we have (N-1) P-equations and NPQ Q-equations. The unknowns are Therefore, the power flow...

Roycourt, Henrik

2012-06-07

433

Performance and emission characteristics of LPG powered four stroke SI engine under variable stroke length and compression ratio  

Microsoft Academic Search

A computer simulation of a variable stroke length, LPG fuelled, four stroke, single cylinder, water cooled spark ignition engine was done. The engine capacity was varied by varying the stroke length of the engine, which also changed its compression ratio. The simulation model developed was verified with experimental results from the literature for both constant and variable stroke engines. The

Hakan Ozcan; Jehad A. A. Yamin

2008-01-01

434

KT McDonald NuFact'14 (U Glasgow) August 29, 2014 1 The High-Power-Target System  

E-print Network

outsert, Stored energy ~ 3 GJ, ~ 100 tons 5 T copper-coil insert. Water-cooled, MgO insulated He Accelerator Staging Scenario · 6.75 GeV (kinetic energy) proton beam with 3 ns (rms) pulse. · 1 MW initial) proposed a 20-T solenoidal capture system. Low-energy 's collected from side of long, thin cylindrical

McDonald, Kirk

435

Target System Concept for a Muon Collider/Neutrino Factory (5th High Power Target Workshop, Fermilab, May 20, 2014)  

E-print Network

, Princeton, NJ 08544 Specifications from the Muon Accelerator Staging Scenario 6.75 GeV (kinetic energy tons 5 T copper-coil insert. Water-cooled, MgO insulated He-gas cooled W-bead shielding (~ 100 tons.8 g/cm3), radiation cooled (with option for convection cooling); liquid metal jet as option for 2-4 MW

McDonald, Kirk

436

Numerical power analysis Isabella Mastroeni  

E-print Network

Numerical power analysis Isabella Mastroeni@arena.sci.univr.it Abstract. In this paper we design abstract domains for numerical power analysis. These domains. Keywords: Abstract interpretation, static program analysis, numerical power analysis, probabilistic

Mastroeni, Isabella

437

GaN power electronics  

E-print Network

Between 5 and 10% of the world's electricity is wasted as dissipated heat in the power electronic circuits needed, for example, in computer power supplies, motor drives or the power inverters of photovoltaic systems. This ...

Lu, Bin

438

Autonomous power system brassboard  

NASA Astrophysics Data System (ADS)

The Autonomous Power System (APS) brassboard is a 20 kHz power distribution system which has been developed at NASA Lewis Research Center, Cleveland, Ohio. The brassboard exists to provide a realistic hardware platform capable of testing artificially intelligent (AI) software. The brassboard's power circuit topology is based upon a Power Distribution Control Unit (PDCU), which is a subset of an advanced development 20 kHz electrical power system (EPS) testbed, originally designed for Space Station Freedom (SSF). The APS program is designed to demonstrate the application of intelligent software as a fault detection, isolation, and recovery methodology for space power systems. This report discusses both the hardware and software elements used to construct the present configuration of the brassboard. The brassboard power components are described. These include the solid-state switches (herein referred to as switchgear), transformers, sources, and loads. Closely linked to this power portion of the brassboard is the first level of embedded control. Hardware used to implement this control and its associated software is discussed. An Ada software program, developed by Lewis Research Center's Space Station Freedom Directorate for their 20 kHz testbed, is used to control the brassboard's switchgear, as well as monitor key brassboard parameters through sensors located within these switches. The Ada code is downloaded from a PC/AT, and is resident within the 8086 microprocessor-based embedded controllers. The PC/AT is also used for smart terminal emulation, capable of controlling the switchgear as well as displaying data from them. Intelligent control is provided through use of a T1 Explorer and the Autonomous Power Expert (APEX) LISP software. Real-time load scheduling is implemented through use of a 'C' program-based scheduling engine. The methods of communication between these computers and the brassboard are explored. In order to evaluate the features of both the brassboard hardware and intelligent controlling software, fault circuits have been developed and integrated as part of the brassboard. A description of these fault circuits and their function is included. The brassboard has become an extremely useful test facility, promoting artificial intelligence (AI) applications for power distribution systems.

Merolla, Anthony

1992-10-01

439

Autonomous power system brassboard  

NASA Technical Reports Server (NTRS)

The Autonomous Power System (APS) brassboard is a 20 kHz power distribution system which has been developed at NASA Lewis Research Center, Cleveland, Ohio. The brassboard exists to provide a realistic hardware platform capable of testing artificially intelligent (AI) software. The brassboard's power circuit topology is based upon a Power Distribution Control Unit (PDCU), which is a subset of an advanced development 20 kHz electrical power system (EPS) testbed, originally designed for Space Station Freedom (SSF). The APS program is designed to demonstrate the application of intelligent software as a fault detection, isolation, and recovery methodology for space power systems. This report discusses both the hardware and software elements used to construct the present configuration of the brassboard. The brassboard power components are described. These include the solid-state switches (herein referred to as switchgear), transformers, sources, and loads. Closely linked to this power portion of the brassboard is the first level of embedded control. Hardware used to implement this control and its associated software is discussed. An Ada software program, developed by Lewis Research Center's Space Station Freedom Directorate for their 20 kHz testbed, is used to control the brassboard's switchgear, as well as monitor key brassboard parameters through sensors located within these switches. The Ada code is downloaded from a PC/AT, and is resident within the 8086 microprocessor-based embedded controllers. The PC/AT is also used for smart terminal emulation, capable of controlling the switchgear as well as displaying data from them. Intelligent control is provided through use of a T1 Explorer and the Autonomous Power Expert (APEX) LISP software. Real-time load scheduling is implemented through use of a 'C' program-based scheduling engine. The methods of communication between these computers and the brassboard are explored. In order to evaluate the features of both the brassboard hardware and intelligent controlling software, fault circuits have been developed and integrated as part of the brassboard. A description of these fault circuits and their function is included. The brassboard has become an extremely useful test facility, promoting artificial intelligence (AI) applications for power distribution systems. However, there are elements of the brassboard which could be enhanced, thus improving system performance. Modifications and enhancements to improve the brassboard's operation are discussed.

Merolla, Anthony

1992-01-01

440

Hybrid Power Management Program Continued  

NASA Technical Reports Server (NTRS)

Hybrid Power Management (HPM) is the innovative integration of diverse, state-of-the-art power devices in an optimal configuration for space and terrestrial applications. The appropriate application and control of the various power devices significantly improves overall system performance and efficiency. The advanced power devices include ultracapacitors and photovoltaics. HPM has extremely wide potential with applications including power-generation, transportation, biotechnology, and space power systems. It may significantly alleviate global energy concerns, improve the environment, and stimulate the economy.

Eichenberg, Dennis J.

2002-01-01

441

Power as a Structural Phenomenon  

Microsoft Academic Search

In an effort to inform empowerment theory and research, this paper provides a structural conception of power. First, we examine\\u000a the essential features present in three dominant conceptions of power in community psychology: social power, psychopolitical\\u000a power, and relational power. Next, commonalities in the key features of power identified by these conceptions are explored\\u000a and pared down to yield a

Jennifer Watling Neal; Zachary P. Neal

442

Captive Water Current Power System  

SciTech Connect

Current energy is converted into shaft power in two stages; First, buoyant power units with stationary hydrofoil wings reach faster than the current speed by sweeping out a captive path. Second, turbines at said power units convert the fast relative local current into shaft power. Power units sweeping along the water surface, using cycloidal turbine methods, as well as power units sweeping on a submerged path, using axial flow turbine methods, are described.

Wuenscher, H. F.; Wuenscher, H. A.

1984-01-31

443

Automated Power-Distribution System  

NASA Technical Reports Server (NTRS)

Automated power-distribution system monitors and controls electrical power to modules in network. Handles both 208-V, 20-kHz single-phase alternating current and 120- to 150-V direct current. Power distributed to load modules from power-distribution control units (PDCU's) via subsystem distributors. Ring busses carry power to PDCU's from power source. Needs minimal attention. Detects faults and also protects against them. Potential applications include autonomous land vehicles and automated industrial process systems.

Thomason, Cindy; Anderson, Paul M.; Martin, James A.

1990-01-01

444

Power Without Wires (POWOW)  

NASA Technical Reports Server (NTRS)

Electric propulsion has emerged as a cost-effective solution to a wide range of satellite applications. Deep Space 1 successfully demonstrated electric propulsion as the primary propulsion source for a satellite. The POWOW concept is a solar-electric propelled spacecraft capable of significant cargo and short trip times for traveling to Mars. There it would enter areosynchronous orbit (Mars GEO equivalent) and beam power to surface installations via lasers. The concept has been developed with industrial partner expertise in high efficiency solar cells, advanced concentrator modules, innovative arrays, and high power electric propulsion systems. The present baseline spacecraft design providing 898 kW using technologies expected to be available in 2003 will be described. Areal power densities approaching 350 W/sq m at 80 C operating temperatures and wing level specific powers of over 350 W/kg are projected. Details of trip times and payloads to Mars are presented. Electric propulsion options include Hall, MPD, and ion thrusters of various power levels and trade studies have been conducted to define the most advantageous options. Because the design is modular, learning curve methodology has been applied to determine expected cost reductions and is included.

Brandhorst, Henry W., Jr.; Howell, Joe (Technical Monitor)

2002-01-01

445

Nuclear Power - Post Fukushima  

NASA Astrophysics Data System (ADS)

The extreme events that led to the prolonged power outage at the Fukushima Daiicchi nuclear plant have highlighted the importance of assuring a means for stable long term cooling of the nuclear fuel and containment following a complete station blackout. Legislative bodies, regulatory agencies and industry are drawing lessons from those events and considering what changes, if any, are needed to nuclear power, post Fukushima. The enhanced safety of a new class of reactor designed by NuScale Power is drawing significant attention in light of the Fukushima events. During normal operation, each NuScale containment is fully immersed in a water-filled stainless steel lined concrete pool that resides underground. The pool, housed in a Seismic Category I building, is large enough to provided 30 days of core and containment cooling without adding water. After 30 days, the decay heat generations coupled with thermal radiation heat transfer is completely adequate to remove core decay heat for an unlimited period of time. These passive power systems can perform their function without requiring an external supply of water of power. An assessment of the NuScale passive systems is being performed through a comprehensive test program that includes the NuScale integral system test facility at Oregon State University

Reyes, Jose, Jr.

2011-10-01

446

Power resource simulation model  

SciTech Connect

The Power Resource Simulation Model (PRSM) was developed by Black & Veatch for the Southwestern Power Administration (Southwestern). Southwestern, one of five power marketing agencies for the US Department of Energy, markets the power and energy generated at 24 US Army Corps of Engineers hydroelectric power plants. PRSM simulates the operation of multipurpose, multireservoir systems and operates the reservoirs to meet user-specified demands (water and electrical) while staying within established operating limits. PRSM is equipped with a graphical user-interface which allows the user to enter and modify input data, initiate the Run program, and view and print simulation results with user-defined tables and graphs. PRSM is operated by specifying demands at each reservoir and for the system as a whole. Once all the individual project demands have been addressed, PRSM operates the reservoirs to meet the system electrical load demands which are input in the form of load duration curves. If the hydropower resources are not capable of meeting the entire system electrical load demand, PRSM will use nonhydro (thermal) resources to meet the remaining system load.

Bultsma, M.L.; Arroyo, J.A. [Black & Veatch, Kansas City, MO (United States); Herrold, B.J. [Southwestern Power Administration, Tulsa, OK (United States)] [and others

1995-12-31

447

Advanced Power Electronics Components  

NASA Technical Reports Server (NTRS)

This paper will give a description and status of the Advanced Power Electronics Materials and Components Technology program being conducted by the NASA Glenn Research Center for future aerospace power applications. The focus of this research program is on the following: 1) New and/or significantly improved dielectric materials for the development of power capacitors with increased volumetric efficiency, energy density, and operating temperature. Materials being investigated include nanocrystalline and composite ceramic dielectrics and diamond-like carbon films; 2) New and/or significantly improved high frequency, high temperature, low loss soft magnetic materials for the development of transformers/inductors with increased power/energy density, electrical efficiency, and operating temperature. Materials being investigated include nanocrystalline and nanocomposite soft magnetic materials; 3) Packaged high temperature, high power density, high voltage, and low loss SiC diodes and switches. Development of high quality 4H- and 6H- SiC atomically smooth substrates to significantly improve device performance is a major emphasis of the SiC materials program; 4) Demonstration of high temperature (> 200 C) circuits using the components developed above.

Schwarze, Gene E.

2004-01-01

448

SATCOM constellation power simulation  

SciTech Connect

Three basic variables directly impact the power and energy generated by the SATCOM satellite constellation and its individual Space Vehicles (SVs). They are (1) telecommunications traffic patterns, (2) network resource management controllables, and (3) system hardware and software performance. This power simulation has verified the robustness of the telecommunications architecture. It has validated the onboard resource allocation process from an SV and network level power and energy perspective. The analyses have led to development of operational procedures that prevent SV node outages, and maximize network telecommunication traffic capacity. The program objective is to optimize overall system operation, availability and quality of service. Achieving this goal requires a thorough understanding of the Electrical Power Subsystem and its interfaces. The EPS simulation model analyzes network level performance by evaluating requirement compliance in the expected operating environments. Specifically, the simulation tool evaluates different design approaches and network operational strategies from a power and energy perspective. As a result, optimal load management solutions will be implemented both on-board the SV and via ground station directed resource allocation strategies.

Capulli, J.; Badke, B.; Davis, G. [Motorola, Chandler, AZ (United States)

1995-12-31

449

Paul Sichta 8th International Conference on Accelerator  

E-print Network

Bldg. RF Generators NSTX Test Cell Control Room Field Coil Pow er Bldgs. Water Cooling #12;Operational Systems Vacuum System Field Coil Power Supply Controls & Water Cooling 2 m 5 MW NBI 6 MW `RF' 0.4 MA CHI of scientific research. · MDSplus clients run on VMS/Unix/Windows. · API's for FORTRAN, C, Java, IDL, and LabView

Princeton Plasma Physics Laboratory

450

Stephen Brooks / s.j.brooks@rl.ac.uk UKNF meeting, Warwick, April 2008  

E-print Network

Stephen Brooks / s.j.brooks@rl.ac.uk UKNF meeting, Warwick, April 2008 Pion Production from Water-Cooled of current UKNF solid target 2. Pros and cons related to water cooling 3. Results from MARS 15.07 ­ Including Where does the proton beam power go? 12.9% 24.3% 62.8% Heat deposited in target Kinetic energy

McDonald, Kirk

451

Organic Fluids and Passive Cooling in a Supercritical Rankine Cycle for Power Generation from Low Grade Heat Sources  

NASA Astrophysics Data System (ADS)

Low grade heat sources have a large amount of thermal energy content. Due to low temperature, the conventional power generation technologies result in lower efficiency and hence cannot be used. In order to efficiently generate power, alternate methods need to be used. In this study, a supercritical organic Rankine cycle was used for heat source temperatures varying from 125C to 200C. Organic refrigerants with zero ozone depletion potential and their mixtures were selected as working fluid for this study while the cooling water temperature was changed from 10-25C. Operating pressure of the cycle has been optimized for each fluid at every heat source temperature to obtain the highest thermal efficiency. Energy and exergy efficiencies of the thermodynamic cycle have been obtained as a function of heat source temperature. Efficiency of a thermodynamic cycle depends significantly on the sink temperature. At areas where water cooling is not available and ambient air temperature is high, efficient power generation from low grade heat sources may be a challenge. Use of passive cooling systems coupled with the condenser was studied, so that lower sink temperatures could be obtained. Underground tunnels, buried at a depth of few meters, were used as earth-air-heat-exchanger (EAHE) through which hot ambient air was passed. It was observed that the air temperature could be lowered by 5-10C in the EAHE. Vertical pipes were used to lower the temperature of water by 5C by passing it underground. Nocturnal cooling of stored water has been studied that can be used to cool the working fluid in the thermodynamic cycle. It was observed that the water temperature can be lowered by 10-20C during the night when it is allowed to cool. The amount of water lost was calculated and was found to be approximately 0.1% over 10 days. The different passive cooling systems were studied separately and their effects on the efficiency of the thermodynamic cycle were investigated. They were then combined into a novel condenser design that uses passive cooling technology to cool the working fluid that was selected in the first part of the study. It was observed that the efficiency of the cycle improved by 2-2.5% when passive cooling system was used.

Vidhi, Rachana

452

Power optimization in logic isomers  

NASA Technical Reports Server (NTRS)

Logic isomers are labeled, 2-isomorphic graphs that implement the same logic function. Logic isomers may have significantly different power requirements even though they have the same number of transistors in the implementation. The power requirements of the isomers depend on the transition activity of the input signals. The power requirements of isomorphic graph isomers of n-input NAND and NOR gates are shown. Choosing the less power-consuming isomer instead of the others can yield significant power savings. Experimental results on a ripple-carry adder are presented to show that the implementation using the least power-consuming isomers requires approximately 10 percent less power than the implementation using the most power-consuming isomers. Simulations of other random logic designs also confirm that designs using less power-consuming isomers can reduce the logic power demand by approximately 10 percent as compared to designs using more power-consuming isomers.

Panwar, Ramesh; Rennels, David; Alkalaj, Leon

1993-01-01

453

Photonic-powered cable assembly  

DOEpatents

A photonic-cable assembly includes a power source cable connector ("PSCC") coupled to a power receive cable connector ("PRCC") via a fiber cable. The PSCC electrically connects to a first electronic device and houses a photonic power source and an optical data transmitter. The fiber cable includes an optical transmit data path coupled to the optical data transmitter, an optical power path coupled to the photonic power source, and an optical feedback path coupled to provide feedback control to the photonic power source. The PRCC electrically connects to a second electronic device and houses an optical data receiver coupled to the optical transmit data path, a feedback controller coupled to the optical feedback path to control the photonic power source, and a photonic power converter coupled to the optical power path to convert photonic energy received over the optical power path to electrical energy to power components of the PRCC.

Sanderson, Stephen N; Appel, Titus James; Wrye, IV, Walter C

2014-06-24

454

Impact of Power Generation Uncertainty on Power System Static Performance  

E-print Network

Impact of Power Generation Uncertainty on Power System Static Performance Yu Christine Chen, Xichen uncer- tainties on the generation side of power systems. We propose a method to assess whether static determined by the forecasted renewable power injection. In our methodology, the uncertainty in generation can

Liberzon, Daniel

455

Analysis of Power System Dynamics Subject to Stochastic Power Injections  

E-print Network

1 Analysis of Power System Dynamics Subject to Stochastic Power Injections Sairaj V. Dhople, Member on power system dynamics with a focus on time scales involving electromechan- ical phenomena), while the power system dynamics are described by the standard differential algebraic equation (DAE

Liberzon, Daniel

456

Trees and Power Lines: Minimizing Conflicts between Electric Power  

E-print Network

Trees and Power Lines: Minimizing Conflicts between Electric Power Infrastructure and the Urban Forest By William Brock Most 1 and Steven Weissman 2 March 10, 2012 #12;iiTrees and Power Lines Trees and Power Lines 5 5. Benefits of the Urban Forest 6 a. Carbon Sequestration 6 b. Property Value 6

Kammen, Daniel M.

457

DYNAMIC MODELLING OF AUTONOMOUS POWER SYSTEMS INCLUDING RENEWABLE POWER SOURCES.  

E-print Network

(thermal, gas, diesel) and renewable (hydro, wind) power units. The objective is to assess the impact system components are developed. Emphasis is given in the representation of different hydro power plantDYNAMIC MODELLING OF AUTONOMOUS POWER SYSTEMS INCLUDING RENEWABLE POWER SOURCES. ABSTRACT The use

Paris-Sud XI, Université de

458

IEEE POWER ENGINEERING SOCIETY ENERGY DEVELOPMENT AND POWER GENERATION COMMITTEE  

E-print Network

IEEE POWER ENGINEERING SOCIETY ENERGY DEVELOPMENT AND POWER GENERATION COMMITTEE Latin America Sponsored by: International Practices for Energy Development and Power Generation Chairs: Luiz Barroso, PSR utilities (Discos) that buy power supply from generators in both the long term and sport markets. For more

Catholic University of Chile (Universidad Católica de Chile)

459

The Power Flow Problem 1 The Power Flow Problem  

E-print Network

.0 Introduction The power flow problem is a very well known problem in the field of power systems engineering commitment and circuit topology) is available. A power flow solution procedure is a numerical method is widely recognized as a fundamental problem for power system analysis, and there are many advanced

McCalley, James D.

460

Maximum power point tracking for low power photovoltaic solar panels  

Microsoft Academic Search

A maximum power point tracker unit is developed for the optimum coupling of photovoltaic panels (PVP) to the batteries and load through a controlled DC-DC power converter (chopper). The system consists of three main units: (i) the photovoltaic panels that convert solar power to electricity; (ii) a chopper which couples the power of PVP to the load or batteries at

Mehmet BODUR; Mummer ERMIS

1994-01-01

461

Solar powered multipurpose remotely powered aircraft  

NASA Technical Reports Server (NTRS)

Environmental problems such as the depletion of the ozone layer and air pollution demand a change in traditional means of propulsion that is sensitive to the ecology. Solar-powered propulsion is a favorable alternative that is both ecologically harmless as well as cost effective. Integration of solar energy into designs ranging from futuristic vehicles to heating is, therefore, beneficial to society. The design and construction of a Multipurpose Remotely Piloted Vehicle (MPRPV) seeks to verify the feasibility of using solar propulsion as a primary fuel source. This task has been a year-long effort by a group of eight students, divided into four teams, each dealing with different aspects of the design. The aircraft was designed to take off, climb to the design altitude, fly in a sustained figure-eight flight path, and cruise for approximately one hour. This mission requires flight at Reynolds numbers between 150,000 and 200,000 and demands special considerations in the aerodynamic design to achieve flight in this regime. Optimal performance requires a lightweight configuration with both structural integrity and maximum power availability. The structural design and choice of solar cells for the propulsion were governed by weight, efficiency, and cost considerations. The final design is an MPRPV weighing 35 N that cruises at 7 m/s at the design altitude of 50 m. The configuration includes a wing composed of balsa and foam NACA 6409 airfoil sections and carbon fiber spars, a tail of similar construction, and a truss structure fuselage. The propulsion system consists of 98 12.5 percent-efficient solar cells donated by Mobil Solar, a NiCad battery for energy storage, and a folding propeller regulated by a lightweight and efficient control system. The airfoils and propeller chosen for the design were researched and tested during the design process.

1991-01-01

462

Power converter connection configuration  

DOEpatents

EMI shielding is provided for power electronics circuits and the like via a direct-mount reference plane support and shielding structure. The thermal support may receive one or more power electronic circuits. The support may aid in removing heat from the circuits through fluid circulating through the support. The support forms a shield from both external EMI/RFI and from interference generated by operation of the power electronic circuits. Features may be provided to permit and enhance connection of the circuitry to external circuitry, such as improved terminal configurations. Modular units may be assembled that may be coupled to electronic circuitry via plug-in arrangements or through interface with a backplane or similar mounting and interconnecting structures.

Beihoff, Bruce C. (Wauwatosa, WI); Kehl, Dennis L. (Milwaukee, WI); Gettelfinger, Lee A. (Brown Deer, WI); Kaishian, Steven C. (Milwaukee, WI); Phillips, Mark G. (Brookfield, WI); Radosevich, Lawrence D. (Muskego, WI)

2008-11-11

463

Power line detection system  

DOEpatents

A short-range, radio frequency (RF) transmitting-receiving system that provides both visual and audio warnings to the pilot of a helicopter or light aircraft of an up-coming power transmission line complex. Small, milliwatt-level narrowband transmitters, powered by the transmission line itself, are installed on top of selected transmission line support towers or within existing warning balls, and provide a continuous RF signal to approaching aircraft. The on-board receiver can be either a separate unit or a portion of the existing avionics, and can also share an existing antenna with another airborne system. Upon receipt of a warning signal, the receiver will trigger a visual and an audio alarm to alert the pilot to the potential power line hazard. 4 figs.

Latorre, V.R.; Watwood, D.B.

1994-09-27

464

Power line detection system  

DOEpatents

A short-range, radio frequency (RF) transmitting-receiving system that provides both visual and audio warnings to the pilot of a helicopter or light aircraft of an up-coming power transmission line complex. Small, milliwatt-level narrowband transmitters, powered by the transmission line itself, are installed on top of selected transmission line support towers or within existing warning balls, and provide a continuous RF signal to approaching aircraft. The on-board receiver can be either a separate unit or a portion of the existing avionics, and can also share an existing antenna with another airborne system. Upon receipt of a warning signal, the receiver will trigger a visual and an audio alarm to alert the pilot to the potential power line hazard.

Latorre, Victor R. (Tracy, CA); Watwood, Donald B. (Tracy, CA)

1994-01-01

465

Electric Power Annual  

EIA Publications

Presents 12 years (2001 - 2012) of national-level data on electricity generating capacity, electricity generation and useful thermal output, fuel receipts, consumption, and emissions. This year's Electric Power Annual has expanded to include several new table series. These include several new annual breakouts of renewable biomass energy sources including wood/wood waste, landfill gas, and biogenic municipal solid waste in Chapter 5 (Consumption of Fossil Fuels); state details of emissions from energy consumption at conventional power plants and combined-heat-and-power plants (Table 9.5); and monthly capacity factors for the past three years and annual capacity factors back to 2008 (Tables 4.8.A. and 4.8.B.)

2013-01-01

466

Discontinuous Mode Power Supply  

NASA Technical Reports Server (NTRS)

A document discusses the changes made to a standard push-pull inverter circuit to avoid saturation effects in the main inverter power supply. Typically, in a standard push-pull arrangement, the unsymmetrical primary excitation causes variations in the volt second integral of each half of the excitation cycle that could lead to the establishment of DC flux density in the magnetic core, which could eventually cause saturation of the main inverter transformer. The relocation of the filter reactor normally placed across the output of the power supply solves this problem. The filter reactor was placed in series with the primary circuit of the main inverter transformer, and is presented as impedance against the sudden changes on the input current. The reactor averaged the input current in the primary circuit, avoiding saturation of the main inverter transformer. Since the implementation of the described change, the above problem has not reoccurred, and failures in the main power transistors have been avoided.

Lagadinos, John; Poulos, Ethel

2012-01-01

467

Unity power factor converter  

NASA Technical Reports Server (NTRS)

A unity power factor converter capable of effecting either inversion (dc-to-dc) or rectification (ac-to-dc), and capable of providing bilateral power control from a DC source (or load) through an AC transmission line to a DC load (or source) for power flow in either direction, is comprised of comparators for comparing the AC current i with an AC signal i.sub.ref (or its phase inversion) derived from the AC ports to generate control signals to operate a switch control circuit for high speed switching to shape the AC current waveform to a sine waveform, and synchronize it in phase and frequency with the AC voltage at the AC ports, by selectively switching the connections to a series inductor as required to increase or decrease the current i.

Wester, Gene W. (Inventor)

1980-01-01

468

Crosswind kite power  

NASA Astrophysics Data System (ADS)

This paper describes a concept for large-scale wind power production by means of aerodynamically efficient kites. Based on aircraft construction, these kites fly transverse to the wind at high speed. The lift produced at this speed is sufficient to both support the kite and generate power. The equations of motion are developed, and examples are presented. One version, based on the C-5A aircraft, results in 6.7 MW produced by a 10-m/s wind. Extrapolation to newer technology, which is more comparable to modern wind turbines, indicates the production of 45 MW from a single machine. The detailed calculations are validated by comparison of their results with simple analytical models. The methodology used here lays the foundation for the systematic study of power-producing kites.

Loyd, M. L.

1980-06-01

469

Powered protrusion cutter  

DOEpatents

An apparatus for clipping a protrusion of material is provided. The protrusion may, for example, be a bolt head, a nut, a rivet, a weld bead, or a temporary assembly alignment tab protruding from a substrate surface of assembled components. The apparatus typically includes a cleaver having a cleaving edge and a cutting blade having a cutting edge. Generally, a mounting structure configured to confine the cleaver and the cutting blade and permit a range of relative movement between the cleaving edge and the cutting edge is provided. Also typically included is a power device coupled to the cutting blade. The power device is configured to move the cutting edge toward the cleaving edge. In some embodiments the power device is activated by a momentary switch. A retraction device is also generally provided, where the retraction device is configured to move the cutting edge away from the cleaving edge.

Bzorgi, Fariborz M. (Knoxville, TN)

2010-03-09

470

Power Systems Development Facility  

SciTech Connect

In support of technology development to utilize coal for efficient, affordable, and environmentally clean power generation, the Power Systems Development Facility (PSDF), located in Wilsonville, Alabama, has routinely demonstrated gasification technologies using various types of coals. The PSDF is an engineering scale demonstration of key features of advanced coal-fired power systems, including a Transport Gasifier, a hot gas particulate control device, advanced syngas cleanup systems, and high-pressure solids handling systems. This final report summarizes the results of the technology development work conducted at the PSDF through January 31, 2009. Twenty-one major gasification test campaigns were completed, for a total of more than 11,000 hours of gasification operation. This operational experience has led to significant advancements in gasification technologies.

Southern Company Services

2009-01-31

471

Solar powered actuator with continuously variable auxiliary power control  

NASA Technical Reports Server (NTRS)

A solar powered system is disclosed in which a load such as a compressor is driven by a main induction motor powered by a solar array. An auxiliary motor shares the load with the solar powered motor in proportion to the amount of sunlight available, is provided with a power factor controller for controlling voltage applied to the auxiliary motor in accordance with the loading on that motor. In one embodiment, when sufficient power is available from the solar cell, the auxiliary motor is driven as a generator by excess power from the main motor so as to return electrical energy to the power company utility lines.

Nola, F. J. (inventor)

1984-01-01

472

Qualification for PowerInsight accuracy of power measurements.  

SciTech Connect

Accuracy of component based power measuring devices forms a necessary basis for research in the area of power-e cient and power-aware computing. The accuracy of these devices must be quanti ed within a reasonable tolerance. This study focuses on PowerInsight, an out- of-band embedded measuring device which takes readings of power rails on compute nodes within a HPC system in realtime. We quantify how well the device performs in comparison to a digital oscilloscope as well as PowerMon2. We show that the accuracy is within a 6% deviation on measurements under reasonable load.

DeBonis, David; Laros, James H.,; Pedretti, Kevin Thomas Tauke

2013-11-01

473

Power management of multi-hundred kilowatt spacecraft power systems  

NASA Technical Reports Server (NTRS)

A NASA-sponsored study of space power distribution system technology is in progress to develop an Autonomously Managed Power System (AMPS) for large space power platforms. The conceptual design of a 250 kW photovoltaic power system, including the power management subsystem (PMS), is presented. A PMS concept is derived based on the need to accommodate the increased complexity of a utility-type power system, and to minimize Shuttle resupply and ground station operational costs. The main PMS functions are discussed along with the control strategies of the autonomously managed power system.

Decker, D. K.; Fleck, G. W.; Graves, J.

1981-01-01

474

Pneumatic Power Supply  

NSDL National Science Digital Library

This brief interactive activity, by Electromechanical Digital Library and Wisconsin Technical College System faculty member Terry Bartelt, begins with a discussion of the three basic components of a pneumatic power system, the prime mover, compressor, and receiver tank. Visitors can learn about each one, its purpose in the system, and how it works through illustrations and animations. The next section discusses and demonstrates power supply operation, with all three parts working to complete the system. This is an excellent resource for electromechanical and pneumatics classes.

Bartelt, Terry L. M.

475

Power To Go  

NSDL National Science Digital Library

Learners observe an electrochemical cell constructed from a small jar containing zinc and copper strips immersed in separate solutions. The strips are connected to a motor that turns a small fan. Learners observe that chemical reactions can produce electricity. This is a one-cell battery, so only creates a small amount of power. Batteries are usually collections of many cells to produce greater amounts of power. This is written as a display, but can easily be adapted for learners to build their own electrochemical reactions.

2012-07-12

476

Perspectives: Powers of Ten  

NSDL National Science Digital Library

In this lab and activity section, students learn to appreciate and understand the scope of science: from the very large and far away, to the very tiny and close-up. A video teaches students about exponential notation and how powers of ten work. The visual clip begins 10 million light years from Earth, moving through space to the Earth, and down to the subatomic world of protons and electrons in powers of 10. A Java activity demonstrates how various specimens appear at different magnifications. A teacher page contains materials, teaching ideas, and extension activities.

Davidson, Michael

477

Nanoconverters for Powering Nanodevices  

NASA Technical Reports Server (NTRS)

Proposed integrated-circuit modules called "nanoconverters" would derive DC power from impinging electromagnetic beams having frequencies in the terahertz range. Nanoconverters are composed of microscopic antennas and diodes resembling rectennas that have been developed to perform the same function at frequencies in the gigahertz range. The submillimeter wavelength nanoconverters would make it possible to incorporate the antenna elements and diodes on structures much smaller than those of prior rectennas, thereby opening up opportunities for noncontact transmission of power to a variety of microelectronic devices, including surgically implanted medical devices and untethered microscopic robots.

Siegel, Peter

2003-01-01

478

Prognostics of Power MOSFET  

NASA Technical Reports Server (NTRS)

This paper demonstrates how to apply prognostics to power MOSFETs (metal oxide field effect transistor). The methodology uses thermal cycling to age devices and Gaussian process regression to perform prognostics. The approach is validated with experiments on 100V power MOSFETs. The failure mechanism for the stress conditions is determined to be die-attachment degradation. Change in ON-state resistance is used as a precursor of failure due to its dependence on junction temperature. The experimental data is augmented with a finite element analysis simulation that is based on a two-transistor model. The simulation assists in the interpretation of the degradation phenomena and SOA (safe operation area) change.

Celaya, Jose Ramon; Saxena, Abhinav; Vashchenko, Vladislay; Saha, Sankalita; Goebel, Kai Frank

2011-01-01

479

Hybrid Power Management  

NASA Technical Reports Server (NTRS)

An engineering discipline denoted as hybrid power management (HPM) has emerged from continuing efforts to increase energy efficiency and reliability of hybrid power systems. HPM is oriented toward integration of diverse electric energy-generating, energy-storing, and energy-consuming devices in optimal configurations for both terrestrial and outer-space applications. The basic concepts of HPM are potentially applicable at power levels ranging from nanowatts to megawatts. Potential applications include terrestrial power-generation, terrestrial transportation, biotechnology, and outer-space power systems. Instances of this discipline at prior stages of development were reported (though not explicitly labeled as HPM) in three prior NASA Tech Briefs articles: "Ultracapacitors Store Energy in a Hybrid Electric Vehicle"(LEW-16876), Vol. 24, No. 4 (April 2000), page 63; "Photovoltaic Power Station With Ultracapacitors for Storage" (LEW-17177), Vol. 27, No. 8 (August 2003), page 38; and "Flasher Powered by Photovoltaic Cells and Ultracapacitors" (LEW-17246), Vol. 24, No. 10 (October 2003), page 37. As the titles of the cited articles indicate, the use of ultracapacitors as energy-storage devices lies at the heart of HPM. An ultracapacitor is an electrochemical energy-storage device, but unlike in a conventional rechargeable electrochemical cell or battery, chemical reactions do not take place during operation. Instead, energy is stored electrostatically at an electrode/electrolyte interface. The capacitance per unit volume of an ultracapacitor is much greater than that of a conventional capacitor because its electrodes have much greater surface area per unit volume and the separation between the electrodes is much smaller. Power-control circuits for ultracapacitors can be simpler than those for batteries, for two reasons: (1) Because of the absence of chemical reactions, charge and discharge currents can be greater than those in batteries, limited only by the electrical resistances of conductors; and (2) whereas the charge level of a battery depends on voltage, temperature, age, and load condition, the charge level of an ultracapacitor, like that of a conventional capacitor, depends only on voltage.

Eichenberg, Dennis

2005-01-01

480

Fuel-cell powered uninterruptible power supply systems: Design considerations  

Microsoft Academic Search

A 1-kVA fuel cell powered, line-interactive uninterruptible power supply (UPS) system that employs modular (fuel cell and power converter) blocks is introduced. Two commercially available proton-exchange membrane fuel cell (2539V, 500W) modules together with suitable dcdc and dcac power electronic converter modules are employed. A supercapacitor module is also used to compensate for the instantaneous power fluctuations and to overcome

Woojin Choi; Jo. W. Howze; Prasad Enjeti

2006-01-01

481

Compressor uses up to 17% less power than units of other designs  

SciTech Connect

This paper describes the Model 25S heavy-duty, single-stage rotary-screw compressor. The compressor is designed for both full-load and partial-load operation. Because the rotors are in contact only along a lubricated pitch line, wear is virtually eliminated. The dimensions of the device are presented in the paper, as well as a photograph of the system itself. A hydrocarbon-based oil is used as the common lubricant, but synthetic organic and silicone-based fluids are also available. The author explains the circulation process of the lubricant. Heat is removed from the lubricant by either a water-cooled heat exchanger or a separate air-cooled unit. In addition, air-cooled or water-cooled aftercoolers, complete with separator and trap, are available.

Not Available

1985-07-08

482

Storage systems for tidal power  

Microsoft Academic Search

The effective use of tidal power by a typical electrical power system requires energy storage to retime the input to meet load demand. The cost of tidal power generation is relatively high and cannot be economically absorbed by the power system as secondary energy. Its constitution is more valuable when delivered at intermediate load factors. Traditional modes of \\

J. Warnock

1974-01-01

483

Supercomputing Power to the People  

E-print Network

Supercomputing Power to the People Arun Chauhan Indiana University #12;Supercomputing power Hursey Andrew Lumsdaine Pooja Malpani Daniel McFarlin Beth Plale Craig Shue #12;Supercomputing power. Sadayappan #12;Supercomputing power to the people Indiana University, March 22, 2006 Programming Languages

Chauhan, Arun

484

MARKET POWER: A DYNAMIC DEFINITION  

Microsoft Academic Search

Market power refers to conditions where the providers of a service can consistently charge prices above those that would be established by a competi- tive market. There are many well known denitions of market power, including indices intended to quantify the degree of market concentration of energy supplies. Market power assessment within electric power markets require the consideration of the

Fernando L. Alvarado

1998-01-01

485

Power generation, operation, and control  

Microsoft Academic Search

This book discusses the economic and engineering aspects used in the planning, operating, and controlling of power generation and transmission systems for electric utilities. It presents advanced mathematical and operations research methods used for electric power engineering problems. It covers methods currently applied in the control and operation of electric power systems. The contents are characteristics of power generation units.

A. J. Wood; B. F. Wollenberg

1984-01-01

486

The Fifth Northwest Electric Power  

E-print Network

demand for electricity, hydro conditions, and forced outages of major power plants. Other uncer- taintiesThe Fifth Northwest Electric Power and Conservation Plan #12;#12;1 Background The Northwest is unique in how it plans its energy future. Through the Northwest Power and Conservation Council's power

487

Power Maps in Algebra and  

E-print Network

Power Maps in Algebra and Topology Kathryn Hess Preface The case of commutative algebras The Hochschild complex of a twisting cochain Power maps on the Hochschild complex Topological relevance Power Compostela, 17 September 2008 #12;Power Maps in Algebra and Topology Kathryn Hess Preface The case

Thévenaz, Jacques

488

Power marketing and renewable energy  

SciTech Connect

Power marketing refers to wholesale and retail transactions of electric power made by companies other than public power entities and the regulated utilities that own the generation and distribution lines. The growth in power marketing has been a major development in the electric power industry during the last few years, and power marketers are expected to realize even more market opportunities as electric industry deregulation proceeds from wholesale competition to retail competition. This Topical Issues Brief examines the nature of the power marketing business and its relationship with renewable power. The information presented is based on interviews conducted with nine power marketing companies, which accounted for almost 54% of total power sales by power marketers in 1995. These interviews provided information on various viewpoints of power marketers, their experience with renewables, and their respective outlooks for including renewables in their resource portfolios. Some basic differences exist between wholesale and retail competition that should be recognized when discussing power marketing and renewable power. At the wholesale level, the majority of power marketers stress the commodity nature of electricity. The primary criteria for developing resource portfolios are the same as those of their wholesale customers: the cost and reliability of power supplies. At the retail level, electricity may be viewed as a product that includes value-added characteristics or services determined by customer preferences.

Fang, J.M.

1997-09-01

489

High-Efficiency Power Module  

NASA Technical Reports Server (NTRS)

One or more embodiments of the present invention pertain to an all solid-state microwave power module. The module includes a plurality of solid-state amplifiers configured to amplify a signal using a low power stage, a medium power stage, and a high power stage. The module also includes a power conditioner configured to activate a voltage sequencer (e.g., bias controller) when power is received from a power source. The voltage sequencer is configured to sequentially apply voltage to a gate of each amplifier and sequentially apply voltage to a drain of each amplifier.

Simons, Rainee N (Inventor); Wintucky, Edwin G (Inventor)

2013-01-01

490

Power generation, operation, and control  

SciTech Connect

This book discusses the economic and engineering aspects used in the planning, operating, and controlling of power generation and transmission systems for electric utilities. It presents advanced mathematical and operations research methods used for electric power engineering problems. It covers methods currently applied in the control and operation of electric power systems. The contents are characteristics of power generation units. Economic Dispatch of Thermal Units and Methods of Solution. Transmission Losses. Unit Commitment. Generation with Limited Energy Supply. Hydrothermal Coordination. Energy Production Cost Models for Fuel Budgeting and Planning. Control of Generation. Interchange Evaluation and Power Pools. Power System Security. An introduction to State Estimation in Power Systems and Appendixes.

Wood, A.J.; Wollenberg, B.F.

1984-01-01

491

Gaussian interferometric power  

NASA Astrophysics Data System (ADS)

The interferometric power of a bipartite quantum state quantifies the precision, measured by quantum Fisher information, that such a state enables for the estimation of a parameter embedded in a unitary dynamics applied to one subsystem only, in the worst-case scenario where a full knowledge of the generator of the dynamics is not available a priori. For finite-dimensional systems, this quantity was proven to be a faithful measure of quantum correlations beyond entanglement. Here we extend the notion of interferometric power to the technologically relevant setting of optical interferometry with continuous-variable probes. By restricting to Gaussian local dynamics, we obtain a closed formula for the interferometric power of all two-mode Gaussian states. We identify separable and entangled Gaussian states which maximize the interferometric power at fixed mean photon number of the probes and discuss the associated metrological scaling. At fixed entanglement of the probes, highly thermalized states can guarantee considerably larger precision than pure two-mode squeezed states.

Adesso, Gerardo

2014-08-01

492

Optimal power factor correction  

SciTech Connect

This paper discusses the different parameters affecting the economic feasibility of power factor correction. It will be shown that the specific costs of the transmission and compensation elements as well as those of the electric energy and power losses have a decisive influence on the achievable overall saving. After formulating an objective function representing this overall saving, taking also the load factor into account an analytical approach to the determination of the optimal size of the compensation equipment is presented. A generalized chart is given which enables the designer to know whether the power factor correction is feasible or not under any circumstances. Also, the most suitable degree of reactive power compensation can be directly found. The results obtained from a digital program are also given to indicate the sensitivity of the optimal compensation factor to changes in system parameters such as the specific energy loss cost and the annual rate of interest and depreciation. Moreover, the good agreement of the results of the digital computation with those determined using the suggested simple generalized chart, could be realized.

Mostafa, M. (Electrical and Computer Engineering Dept., College of Engineering and Petroleum, Kuwait Univ. (KW))

1988-08-01

493

Solar Sea Power  

ERIC Educational Resources Information Center

In their preoccupation with highly complex new energy systems, scientists and statesmen may be overlooking the possibilities of Ocean Thermal Energy Conversion (OTEC). That is the view of a Carnegie-Mellon University physicist who is in the forefront of solar sea power investigation. (Author/BT)

Zener, Clarence

1976-01-01

494

Solar Thermal Power.  

ERIC Educational Resources Information Center

The different approaches to the generation of power from solar energy may be roughly divided into five categories: distributed collectors; central receivers; biomass; ocean thermal energy conversion; and photovoltaic devices. The first approach (distributed collectors) is the subject of this module. The material presented is designed to

McDaniels, David K.