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1

Counter flow cooling characteristics with liquid nitrogen for superconducting power cables  

Microsoft Academic Search

Counter flow cooling is one of effective cooling systems for superconducting power transmission cables to save space. In designing of HTc superconducting power cables, investigating cooling characteristics with liquid nitrogen is important. We have conducted counter flow cooling tests of a 100-m long duplex-counter-flow tube with liquid nitrogen and obtained basic data of initial cooling and temperature distributions along the

Mitsuho Furuse; Shuichiro Fuchino; Noboru Higuchi

2002-01-01

2

Micro Power Grid System With SMES and Superconducting Cable Modules Cooled by Liquid Hydrogen  

Microsoft Academic Search

For future power system, a micro power grid system, which is mainly composed of several power modules, such as superconducting (SC) cable, superconducting magnetic energy storage (SMES) system, hydrogen system, fuel cell (FC) system, renewable energy modules, and power converter modules, is expected. In the grid system, hydrogen mainly produced by renewable energy is liquefied for cooling down of the

Tomonori Nakayama; Tsuyoshi Yagai; Makoto Tsuda; Takataro Hamajima

2009-01-01

3

Peltier cooling of superconducting current leads  

Microsoft Academic Search

An interesting application of Peltier cooling based on the Peltier materials presently available arises for the cooling of current leads connected to superconducting power electronics. By inserting n-doped and p-doped Peltier tablets at the warm end into the circuit, at their warm side the remaining current leads can be Peltier cooled about 50–60 K below room temperature. We have developed

F. K. Gehring; M. E. Hüttner; R. P. Huebener

2001-01-01

4

Cooling and electrical excitation of 100 m superconducting power transmission cables  

SciTech Connect

The design of a test facility for superconducting power transmission cables is described. The cryogenic portion consists of a screw compressor, cold box with turbine expanders, 100 m of transfer line and 100 m of cable enclosure. The complete cryogenic system has been operated and performance figures are given. The cables will be operated at voltage and current by electrical equipment which has mostly been installed and tested. The interface between the low-temperature cables and the outside are four termination bushings which are under construction; a brief description is included.

Forsyth, E B; Gibbs, R J; Jensen, J E; McNernery, A J

1980-01-01

5

Superconducting Power Generation  

E-print Network

The superconducting ac generator has the greatest potential for large-scale commercial application of superconductivity that can benefit the public. Electric power is a vital ingredient of modern society, and generation may be considered to be the vital ingredient of a power system. This articles gives background, and an insight into the physics and engineering of superconducting power generation.

Mario Rabinowitz

2003-02-20

6

Power superconducting power transmission cable  

DOEpatents

The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

Ashworth, Stephen P. (Cambridge, GB)

2003-01-01

7

Electric power applications of superconductivity  

Microsoft Academic Search

The development of superconducting systems for electric power is driven by the promise of improved efficiency, smaller size, and reduced weight as compared to existing technologies and by the possibility of new applications. Superconducting power components can also contribute to improved power quality and increased system reliability. This paper addresses historical developments and technology status of four superconducting power applications:

WILLIAM V. HASSENZAHL; DREW W. HAZELTON; BRIAN K. JOHNSON; PETER KOMAREK; MATHIAS NOE; CHANDRA T. REIS

2004-01-01

8

Cooling of Color Superconducting Compact Stars  

E-print Network

We review the status of research on the cooling of compact stars, with emphasis on the influence of color superconducting quark matter phases. Although a consistent microscopic approach is not yet available, severe constraints on the phase structure of matter at high densities come from recent mass and cooling observations of compact stars.

David Blaschke

2006-03-26

9

Long distance renewable-energy-sources power transmission using hydrogen-cooled MgB 2 superconducting line  

NASA Astrophysics Data System (ADS)

Renewable Energy Sources (RES) exploitation for electric energy and hydrogen production has been identified as one of the leading ways towards a future sustainable energy system. Hydrogen can be stored and transported in gaseous (GH 2) or liquid form (LH 2). When large hydrogen storage is required, liquefaction can be convenient with respect to compression, because of its higher storage density. LH 2 can also be used as a coolant for superconducting lines, acting at the same time as energy vector and cryogen. In particular, in this paper we focus on the MgB 2 material mainly due to economic considerations and working temperature match with LH 2. A system for large scale RES exploitation allowing flexible and controlled delivery of electric energy and LH 2 is presented. For the thermo-hydraulic design, a method is proposed which resorts to compressible fluid equations put in a convenient simplified form. A case application with 20 km distance between cooling stations is considered, and the need of taking into account LH 2 compressibility for pipeline design is shown.

Trevisani, L.; Fabbri, M.; Negrini, F.

2007-02-01

10

Power electronics cooling apparatus  

DOEpatents

A semiconductor cooling arrangement wherein a semiconductor is affixed to a thermally and electrically conducting carrier such as by brazing. The coefficient of thermal expansion of the semiconductor and carrier are closely matched to one another so that during operation they will not be overstressed mechanically due to thermal cycling. Electrical connection is made to the semiconductor and carrier, and a porous metal heat exchanger is thermally connected to the carrier. The heat exchanger is positioned within an electrically insulating cooling assembly having cooling oil flowing therethrough. The arrangement is particularly well adapted for the cooling of high power switching elements in a power bridge.

Sanger, Philip Albert (Monroeville, PA); Lindberg, Frank A. (Baltimore, MD); Garcen, Walter (Glen Burnie, MD)

2000-01-01

11

Cooling modes for superconducting magnets  

SciTech Connect

The requirements to be met for a conductor design are enumerated in a way which shows how the choice of the cooling mode affects each parameter. These requirements include aspects concerning the coil protection, the mechanical behavior and the thermal behavior. The possible cooling modes are analyzed by distinguishing between the roles which are played by the fluid and by the geometry. A review of essential properties of helium in its different states is given. Heat exchange properties and implementation problems are considered. Compromise solutions used in different projects are analyzed. 41 refs.

Claudet, G.

1981-09-01

12

Cooling system for superconducting magnet  

DOEpatents

A cooling system is configured to control the flow of a refrigerant by controlling the rate at which the refrigerant is heated, thereby providing an efficient and reliable approach to cooling a load (e.g., magnets, rotors). The cooling system includes a conduit circuit connected to the load and within which a refrigerant circulates; a heat exchanger, connected within the conduit circuit and disposed remotely from the load; a first and a second reservoir, each connected within the conduit, each holding at least a portion of the refrigerant; a heater configured to independently heat the first and second reservoirs. In a first mode, the heater heats the first reservoir, thereby causing the refrigerant to flow from the first reservoir through the load and heat exchanger, via the conduit circuit and into the second reservoir. In a second mode, the heater heats the second reservoir to cause the refrigerant to flow from the second reservoir through the load and heat exchanger via the conduit circuit and into the first reservoir.

Gamble, Bruce B. (Wellesley, MA); Sidi-Yekhlef, Ahmed (Framingham, MA)

1998-01-01

13

Cooling system for superconducting magnet  

DOEpatents

A cooling system is configured to control the flow of a refrigerant by controlling the rate at which the refrigerant is heated, thereby providing an efficient and reliable approach to cooling a load (e.g., magnets, rotors). The cooling system includes a conduit circuit connected to the load and within which a refrigerant circulates; a heat exchanger, connected within the conduit circuit and disposed remotely from the load; a first and a second reservoir, each connected within the conduit, each holding at least a portion of the refrigerant; a heater configured to independently heat the first and second reservoirs. In a first mode, the heater heats the first reservoir, thereby causing the refrigerant to flow from the first reservoir through the load and heat exchanger, via the conduit circuit and into the second reservoir. In a second mode, the heater heats the second reservoir to cause the refrigerant to flow from the second reservoir through the load and heat exchanger via the conduit circuit and into the first reservoir. 3 figs.

Gamble, B.B.; Sidi-Yekhlef, A.

1998-12-15

14

Progress on Superconducting Magnets for the MICE Cooling Channel  

Microsoft Academic Search

The muon ionization cooling experiment (MICE) consists of a target, a beam line, a pion decay channel, the MICE cooling channel. Superconducting magnets are used in the pion decay channel and the MICE cooling channel. This report describes the MICE cooling channel magnets and the progress in the design and fabrication of these magnets. The MICE cooling channel consists of

Michael A Green; Steve P. Virostek; Derun Li; Michael S. Zisman; Li Wang; Heng Pan; Hong Wu; XingLong Guo; FengYu Xu; X. K. Liu; S. X. Zheng; Thomas Bradshaw; Elwyn Baynham; John Cobb; Wing Lau; Peter Lau; Stephanie Q. Yang

2009-01-01

15

Cooling of superconducting devices by liquid storage and refrigeration unit  

DOEpatents

A system is disclosed for cooling superconducting devices. The system includes a cryogen cooling system configured to be coupled to the superconducting device and to supply cryogen to the device. The system also includes a cryogen storage system configured to supply cryogen to the device. The system further includes flow control valving configured to selectively isolate the cryogen cooling system from the device, thereby directing a flow of cryogen to the device from the cryogen storage system.

Laskaris, Evangelos Trifon; Urbahn, John Arthur; Steinbach, Albert Eugene

2013-08-20

16

Performance of an internally cooled superconducting solenoid  

SciTech Connect

A superconducting magnet constructed of an internally cooled solenoid has been produced and tested. Particular emphasis was placed on measurement of the stability margins of the magnet. Test results showed that this magnet has demonstrated the following merits: (1) it reached short sample critical current limit with no training; (2) no degradation due to strand motion in fields was apparent; (3) it can be charged and discharged to high current densities and high fields at a fast rate; (4) it has reasonable stability margin up to 90% of the critical current; (5) stability measurements verify the scaling relationship for a limiting current below which there is single valued high stability margin; (6) it is not really necessary to have bulk helium flow to ensure high stability; and (7) very high pulse field changes can be accommodated as long as the energy deposition is within its stability margin.

Lue, J.W.; Miller, J.R.

1981-01-01

17

Inhomogeneous color superconductivity and the cooling of compact stars  

E-print Network

In this talk I discuss the inhomogeneous (LOFF) color superconductive phases of Quantum Chromodynamics (QCD). In particular, I show the effect of a core of LOFF phase on the cooling of a compact star.

M. Ruggieri

2007-04-13

18

Cryogenic system with the sub-cooled liquid nitrogen for cooling HTS power cable  

Microsoft Academic Search

A 10m long, three-phase AC high-temperature superconducting (HTS) power cable had been fabricated and tested in China August 2003. The sub-cooled liquid nitrogen (LN2) was used to cool the HTS cable. The sub-cooled LN2 circulation was built by means of a centrifugal pump through a heat exchanger in the sub-cooler, the three-phase HTS cable cryostats and a LN2 gas–liquid separator.

Y. F. Fan; L. H. Gong; X. D. Xu; L. F. Li; L. Zhang; L. Y. Xiao

2005-01-01

19

Direct cooled power electronics substrate  

DOEpatents

The disclosure describes directly cooling a three-dimensional, direct metallization (DM) layer in a power electronics device. To enable sufficient cooling, coolant flow channels are formed within the ceramic substrate. The direct metallization layer (typically copper) may be bonded to the ceramic substrate, and semiconductor chips (such as IGBT and diodes) may be soldered or sintered onto the direct metallization layer to form a power electronics module. Multiple modules may be attached to cooling headers that provide in-flow and out-flow of coolant through the channels in the ceramic substrate. The modules and cooling header assembly are preferably sized to fit inside the core of a toroidal shaped capacitor.

Wiles, Randy H [Powell, TN; Wereszczak, Andrew A [Oak Ridge, TN; Ayers, Curtis W. (Kingston, TN) [Kingston, TN; Lowe, Kirk T. (Knoxville, TN) [Knoxville, TN

2010-09-14

20

Magnetic Flux Dynamics in Horizontally Cooled Superconducting Cavities  

E-print Network

Previous studies on magnetic flux expulsion as a function of cooling details have been performed for superconducting niobium cavities with the cavity beam axis placed parallel respect to the helium cooling flow, and findings showed that for sufficient cooling thermogradients all magnetic flux could be expelled and very low residual resistance could be achieved. In this paper we investigate the flux trapping and its impact on radio frequency surface resistance when the resonators are positioned perpendicularly to the helium cooling flow, which is representative of how superconducting radio-frequency (SRF) cavities are cooled in an accelerator. We also extend the studies to different directions of applied magnetic field surrounding the resonator. Results show that in the cavity horizontal configuration there is a different impact of the various field components on the final surface resistance, and that several parameters have to be considered to understand flux dynamics. A newly discovered phenomenon of concent...

Martinello, M; Grassellino, A; Crawford, A C; Melnychuk, O; Romanenko, A; Sergatkov, D A

2015-01-01

21

Cooling arrangement for a superconducting coil  

DOEpatents

A superconducting device, such as a superconducting rotor for a generator or motor. A vacuum enclosure has an interior wall surrounding a cavity containing a vacuum. A superconductive coil is placed in the cavity. A generally-annularly-arranged, thermally-conductive sheet has an inward-facing surface contacting generally the entire outward-facing surface of the superconductive coil. A generally-annularly-arranged coolant tube contains a cryogenic fluid and contacts a generally-circumferential portion of the outward-facing surface of the sheet. A generally-annularly-arranged, thermally-insulative coil overwrap generally circumferentially surrounds the sheet. The coolant tube and the inward-facing surface of the coil overwrap together contact generally the entire outward-facing surface of the sheet.

Herd, Kenneth Gordon (Niskayuna, NY); Laskaris, Evangelos Trifon (Schenectady, NY)

1998-06-30

22

Cooling arrangement for a superconducting coil  

DOEpatents

A superconducting device is disclosed, such as a superconducting rotor for a generator or motor. A vacuum enclosure has an interior wall surrounding a cavity containing a vacuum. A superconductive coil is placed in the cavity. A generally-annularly-arranged, thermally-conductive sheet has an inward-facing surface contacting generally the entire outward-facing surface of the superconductive coil. A generally-annularly-arranged coolant tube contains a cryogenic fluid and contacts a generally-circumferential portion of the outward-facing surface of the sheet. A generally-annularly-arranged, thermally-insulative coil overwrap generally circumferentially surrounds the sheet. The coolant tube and the inward-facing surface of the coil overwrap together contact generally the entire outward-facing surface of the sheet. 3 figs.

Herd, K.G.; Laskaris, E.T.

1998-06-30

23

System and method for cooling a super-conducting device  

DOEpatents

A system and method for cooling a superconductive rotor coil. The system comprises a rotatable shaft coupled to the superconductive rotor coil. The rotatable shaft may comprise an axial passageway extending through the rotatable shaft and a first passageway extending through a wall of the rotatable shaft to the axial passageway. The axial passageway and the first passageway are operable to convey a cryogenic fluid to the superconductive rotor coil through the wall of the rotatable shaft. A cryogenic transfer coupling may be provided to supply cryogenic fluid to the first passageway.

Bray, James William (Niskayuna, NY); Steinbach, Albert Eugene (Schenectady, NY); Dawson, Richard Nils (Voorheesville, NY); Laskaris, Evangelos Trifon (Schenectady, NY); Huang, Xianrul (Clifton Park, NY)

2008-01-08

24

System and method for cooling a superconducting rotary machine  

SciTech Connect

A system for cooling a superconducting rotary machine includes a plurality of sealed siphon tubes disposed in balanced locations around a rotor adjacent to a superconducting coil. Each of the sealed siphon tubes includes a tubular body and a heat transfer medium disposed in the tubular body that undergoes a phase change during operation of the machine to extract heat from the superconducting coil. A siphon heat exchanger is thermally coupled to the siphon tubes for extracting heat from the siphon tubes during operation of the machine.

Ackermann, Robert Adolf (Schenectady, NY); Laskaris, Evangelos Trifon (Schenectady, NY); Huang, Xianrui (Clifton Park, NY); Bray, James William (Niskayuna, NY)

2011-08-09

25

Development of a 500 kVA-class oxide-superconducting power transformer operated at liquid-nitrogen temperature 1 An extended version of the following paper presented in ICEC16\\/ICMC (Kitakyushu, 1996). Funaki, K. et al. Design and construction of a 500 kVA-class oxide superconducting power transformer cooled by liquid nitrogen Proc. of ICEC16\\/ICMC (1997) Part 2 1009-1012 1  

Microsoft Academic Search

We have designed and constructed a 500 kVA-class oxide-superconducting power transformer. The windings are cooled by liquid nitrogen or subcooled nitrogen in a G-FRP cryostat of 785mm in diameter and 1210mm in height, that has a room-temperature space for an iron core with the diameter of 314mm. The primary and secondary windings are three-strand and six-strand parallel conductors of a

K Funaki; M Iwakuma; K Kajikawa; M Takeo; J Suehiro; M Hara; K Yamafuji; M Konno; Y Kasagawa; K Okubo; Y Yasukawa; S Nose; M Ueyama; K Hayashi; K Sato

1998-01-01

26

Progress on Superconducting Magnets for the MICE Cooling Channel  

SciTech Connect

The muon ionization cooling experiment (MICE) consists of a target, a beam line, a pion decay channel, the MICE cooling channel. Superconducting magnets are used in the pion decay channel and the MICE cooling channel. This report describes the MICE cooling channel magnets and the progress in the design and fabrication of these magnets. The MICE cooling channel consists of three types of superconducting solenoids; the spectrometer solenoids, the coupling solenoids and the focusing solenoids. The three types of magnets are being fabricated in he United States, China, and the United Kingdom respectively. The spectrometer magnets are used to analyze the muon beam before and after muon cooling. The coupling magnets couple the focusing sections and keep the muon beam contained within the iris of the RF cavities that re used to recover the muon momentum lost during ionization cooling. The focusing magnets focus the muon beam in the center of a liquid hydrogen absorber. The first of the cooling channel magnets will be operational in MICE in the spring of 2010.

Green, Michael A; Virostek, Steve P.; Li, Derun; Zisman, Michael S.; Wang, Li; Pan, Heng; Wu, Hong; Guo, XingLong; Xu, FengYu; Liu, X. K.; Zheng, S. X.; Bradshaw, Thomas; Baynham, Elwyn; Cobb, John; Lau, Wing; Lau, Peter; Yang, Stephanie Q.

2009-09-09

27

Magnetar superconductivity versus magnetism: neutrino cooling processes  

E-print Network

We describe the microphysics, phenomenology, and astrophysical implication of a $B$-field induced unpairing effect that may occur in magnetars, if the local $B$-field in the core of a magnetar exceeds a critical value $H_{c2}$. Using the Ginzburg-Landau (GL) theory of superconductivity, we derive the $H_{c2}$ field for proton condensate taking into the correction ($\\le 30\\%$) which arises from its coupling to the background neutron condensate. The density dependence of pairing of proton condensate implies that $H_{c2}$ is maximal at the crust-core interface and decreases towards the center of the star. As a consequence, magnetar cores with homogenous constant fields will be partially superconducting for "medium-field" magnetars ($10^{15}\\le B\\le 5 \\times 10^{16}$ G) whereas "strong-field" magnetars ($B>5\\times 10^{16}$ G) will be void of superconductivity. The emissivity of a magnetar's core changes in twofold manner: (i)~the $B$-field assisted direct Urca process is enhanced by orders of magnitude, because o...

Sinha, Monika

2015-01-01

28

Magnetar superconductivity versus magnetism: Neutrino cooling processes  

NASA Astrophysics Data System (ADS)

We describe the microphysics, phenomenology, and astrophysical implication of a B -field induced unpairing effect that may occur in magnetars, if the local B field in the core of a magnetar exceeds a critical value Hc 2. Using the Ginzburg-Landau theory of superconductivity, we derive the Hc 2 field for proton condensate taking into the correction (?30 % ) which arises from its coupling to the background neutron condensate. The density dependence of pairing of proton condensate implies that Hc 2 is maximal at the crust-core interface and decreases towards the center of the star. As a consequence, magnetar cores with homogenous constant fields will be partially superconducting for "medium-field" magnetars (1015?B ?5 ×1016G) whereas "strong-field" magnetars (B >5 ×1016G) will be void of superconductivity. The neutrino emissivity of a magnetar's core changes in a twofold manner: (i) the B -field assisted direct Urca process is enhanced by orders of magnitude, because of the unpairing effect in regions where B ?Hc 2 ; (ii) the Cooper-pair breaking processes on protons vanish in these regions and the overall emissivity by the pair-breaking processes is reduced by a factor of only a few.

Sinha, Monika; Sedrakian, Armen

2015-03-01

29

Microwave-induced cooling of a superconducting qubit.  

PubMed

We demonstrated microwave-induced cooling in a superconducting flux qubit. The thermal population in the first-excited state of the qubit is driven to a higher-excited state by way of a sideband transition. Subsequent relaxation into the ground state results in cooling. Effective temperatures as low as approximately 3 millikelvin are achieved for bath temperatures of 30 to 400 millikelvin, a cooling factor between 10 and 100. This demonstration provides an analog to optical cooling of trapped ions and atoms and is generalizable to other solid-state quantum systems. Active cooling of qubits, applied to quantum information science, provides a means for qubit-state preparation with improved fidelity and for suppressing decoherence in multi-qubit systems. PMID:17158325

Valenzuela, Sergio O; Oliver, William D; Berns, David M; Berggren, Karl K; Levitov, Leonid S; Orlando, Terry P

2006-12-01

30

Electrical Breakdown Characteristics of Superconducting Magnet System in Sub-Cooled Liquid Nitrogen  

Microsoft Academic Search

Dielectric characteristics of gaseous helium (GHe) injected into the cooling system to make sub-cooled nitrogen condition with constant pressure is found to be extraordinarily weak in dielectric strength by H. Mitsuii (1998). In high voltage superconducting machines using the sub-cooled nitrogen cooling system, the current lead part in GHe environment could be electrical weak points rather than the superconducting magnet

Hyoungku Kang; Chanjoo Lee; Tae Kuk Ko; Bok-Yeol Seok

2007-01-01

31

Dry Cooling for Power Stations  

Microsoft Academic Search

As growing interest is shown in inairect ary cooling plants for power stations, experiences gained in such plants having been in operation for 6-17 years are summarized. Solely a few important questions are dealt with, such as materials and corrosion of heat exchangers, mechanical and natural draft, wind effect and cooler arrangement, direct contact and surface condensers. This paper should

L. Forgo

1979-01-01

32

Solar-powered cooling system  

DOEpatents

A solar-powered adsorption-desorption refrigeration and air conditioning system uses nanostructural materials made of high specific surface area adsorption aerogel as the adsorptive media. Refrigerant molecules are adsorbed on the high surface area of the nanostructural material. A circulation system circulates refrigerant from the nanostructural material to a cooling unit.

Farmer, Joseph C

2013-12-24

33

Heat pipe cooled power magnetics  

NASA Technical Reports Server (NTRS)

A high frequency, high power, low specific weight (0.57 kg/kW) transformer developed for space use was redesigned with heat pipe cooling allowing both a reduction in weight and a lower internal temperature rise. The specific weight of the heat pipe cooled transformer was reduced to 0.4 kg/kW and the highest winding temperature rise was reduced from 40 C to 20 C in spite of 10 watts additional loss. The design loss/weight tradeoff was 18 W/kg. Additionally, allowing the same 40 C winding temperature rise as in the original design, the KVA rating is increased to 4.2 KVA, demonstrating a specific weight of 0.28 kg/kW with the internal loss increased by 50W. This space environment tested heat pipe cooled design performed as well electrically as the original conventional design, thus demonstrating the advantages of heat pipes integrated into a high power, high voltage magnetic. Another heat pipe cooled magnetic, a 3.7 kW, 20A input filter inductor was designed, developed, built, tested, and described. The heat pipe cooled magnetics are designed to be Earth operated in any orientation.

Chester, M. S.

1979-01-01

34

Cooling of Neutron Stars with Color Superconducting Quark Cores  

E-print Network

We show that within a recently developed nonlocal chiral quark model the critical density for a phase transition to color superconducting quark matter under neutron star conditions can be low enough for these phases to occur in compact star configurations with masses below 1.3 M_sun. We study the cooling of these objects in isolation for different values of the gravitational mass and argue that, if the quark matter phase would allow unpaired quarks, the corresponding hybrid stars would cool too fast. The comparison with observational data puts tight constraints on possible color superconducting quark matter phases. Possible candidates with diquark gaps of the order of 10 keV - 1 MeV such as the "2SC+X" and the color spin locking (CSL) phase are presented.

David Blaschke; Dmitri N. Voskresensky; Hovik Grigorian

2005-11-03

35

Cryogenic performance of a cryocooler-cooled superconducting undulator  

SciTech Connect

A cryocooler-cooled superconducting undulator has been installed and operated with beam at the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). The device consists of a dual-core 42-pole magnet structure that is cooled to 4.2 K with a system of four cryocoolers operating in a zero-boil-off configuration. This effort represents the culmination of a development program to establish concept feasibility and evaluate cryostat design and cryocooler-based refrigeration. Cryostat performance is described including cool-down/warm-up, steady-state operation, cooling margin, and the impact of beam during operation in the APS storage ring. Plans for future devices with longer magnets, which will incorporate lessons learned from the development program, are also discussed.

Fuerst, J. D.; Doose, C.; Hasse, Q.; Ivanyushenkov, Y.; Kasa, M.; Shiroyanagi, Y. [Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

2014-01-29

36

Thermoelectric cooling and power generation  

PubMed

In a typical thermoelectric device, a junction is formed from two different conducting materials, one containing positive charge carriers (holes) and the other negative charge carriers (electrons). When an electric current is passed in the appropriate direction through the junction, both types of charge carriers move away from the junction and convey heat away, thus cooling the junction. Similarly, a heat source at the junction causes carriers to flow away from the junction, making an electrical generator. Such devices have the advantage of containing no moving parts, but low efficiencies have limited their use to specialty applications, such as cooling laser diodes. The principles of thermoelectric devices are reviewed and strategies for increasing the efficiency of novel materials are explored. Improved materials would not only help to cool advanced electronics but could also provide energy benefits in refrigeration and when using waste heat to generate electrical power. PMID:10426986

DiSalvo

1999-07-30

37

Thermoelectric Devices Cool, Power Electronics  

NASA Technical Reports Server (NTRS)

Nextreme Thermal Solutions Inc., based in Research Triangle Park, North Carolina, licensed thermoelectric technology from NASA s Jet Propulsion Laboratory. This has allowed the company to develop cutting edge, thin-film thermoelectric coolers that effective remove heat generated by increasingly powerful and tightly packed microchip components. These solid-state coolers are ideal solutions for applications like microprocessors, laser diodes, LEDs, and even potentially for cooling the human body. Nextreme s NASA technology has also enabled the invention of thermoelectric generators capable of powering technologies like medical implants and wireless sensor networks.

2009-01-01

38

Surface Power Radiative Cooling Tests  

SciTech Connect

Terrestrial nuclear power plants typically maintain their temperature through convective cooling, such as water and forced air. However, the space environment is a vacuum environment, typically 10-8 Torr pressure, therefore in proposed missions to the lunar surface, power plants would have to rely on radiative cooling to remove waste heat. Also, the Martian surface has a very tenuous atmosphere (e.g. {approx}5 Torr CO2), therefore, the main heat transfer method on the Martian surface is also radiative. Because of the lack of atmosphere on the Moon and the tenuous atmosphere on Mars, surface power systems on both the Lunar and Martian surface must rely heavily on radiative heat transfer. Because of the large temperature swings on both the lunar and the Martian surfaces, trying to radiate heat is inefficient. In order to increase power system efficiency, an effort is underway to test various combinations of materials with high emissivities to demonstrate their ability to survive these degrading atmospheres to maintain a constant radiator temperature improving surface power plant efficiency. An important part of this effort is the development of a unique capability that would allow the determination of a materials emissivity at high temperatures. A description of the test capability as well as initial data is presented.

Vaughn, Jason; Schneider, Todd [Environmental Effects Branch, EM50, NASA Marshall Space Flight Center, AL 35812 (United States)

2006-01-20

39

Surface Power Radiative Cooling Tests  

NASA Astrophysics Data System (ADS)

Terrestrial nuclear power plants typically maintain their temperature through convective cooling, such as water and forced air. However, the space environment is a vacuum environment, typically 10-8 Torr pressure, therefore in proposed missions to the lunar surface, power plants would have to rely on radiative cooling to remove waste heat. Also, the Martian surface has a very tenuous atmosphere (e.g. ~5 Torr CO2), therefore, the main heat transfer method on the Martian surface is also radiative. Because of the lack of atmosphere on the Moon and the tenuous atmosphere on Mars, surface power systems on both the Lunar and Martian surface must rely heavily on radiative heat transfer. Because of the large temperature swings on both the lunar and the Martian surfaces, trying to radiate heat is inefficient. In order to increase power system efficiency, an effort is underway to test various combinations of materials with high emissivities to demonstrate their ability to survive these degrading atmospheres to maintain a constant radiator temperature improving surface power plant efficiency. An important part of this effort is the development of a unique capability that would allow the determination of a materials emissivity at high temperatures. A description of the test capability as well as initial data is presented.

Vaughn, Jason; Schneider, Todd

2006-01-01

40

ASSESSING POWER PLANT COOLING WATER INTAKE SYSTEM  

E-print Network

ASSESSING POWER PLANT COOLING WATER INTAKE SYSTEM ENTRAINMENT IMPACTS Prepared For: California power plants and other industrial facilities that withdraw cooling water from surface water bodies regulated under Section 316(b), steam electric power plants represent the largest cooling water volumes

41

Impact of cool-down conditions at Tc on the superconducting rf cavity quality factor  

NASA Astrophysics Data System (ADS)

Many next-generation, high-gradient accelerator applications, from energy-recovery linacs to accelerator-driven systems (ADS) rely on continuous wave (CW) operation for which superconducting radio-frequency (SRF) systems are the enabling technology. However, while SRF cavities dissipate little power, they must be cooled by liquid helium and for many CW accelerators the complexity as well as the investment and operating costs of the cryoplant can prove to be prohibitive. We investigated ways to reduce the dynamic losses by improving the residual resistance (Rres) of niobium cavities. Both the material treatment and the magnetic shielding are known to have an impact. In addition, we found that Rres can be reduced significantly when the cool-down conditions during the superconducting phase transition of the niobium are optimized. We believe that not only do the cool-down conditions impact the level to which external magnetic flux is trapped in the cavity but also that thermoelectric currents are generated which in turn create additional flux that can be trapped. Therefore, we investigated the generation of flux and the dynamics of flux trapping and release in a simple model niobium-titanium system that mimics an SRF cavity in its helium tank. We indeed found that thermal gradients along the system during the superconducting transition can generate a thermoelectric current and magnetic flux, which subsequently can be trapped. These effects may explain the observed variation of the cavity’s Rres with cool-down conditions.

Vogt, J.-M.; Kugeler, O.; Knobloch, J.

2013-10-01

42

Optimal cool-down time of a 4 K superconducting magnet cooled by a two-stage cryocooler  

NASA Astrophysics Data System (ADS)

A cool-down time is one of the major factors in many cryocooler applications, especially for the design of conduction-cooled superconducting devices. Cool-down time means a time cooling a thermal mass from a room-temperature to cryogenic-temperature within a stipulated amount of time. The estimation of cool-down time seeks the elapsed time to cool the thermal object by a cryocooler during initial cool-down process. This procedure includes the dimension and properties of thermal object, heat transfer analysis for cryogenic load, thermal interface between cold mass and cryocooler, and available refrigeration capacity of cryocooler. The proposed method is applied to the specific cooling system for 3 T superconducting magnet cooled by a two-stage GM cryocooler. The result is compared with that of experiment, showing that proposed method has a good agreement with experiment. In addition, the initial cool-down time can be shortened by employing thermal link between the cold mass and first-stage of cryocooler. Through a rigorous modeling and analysis taking into account the effect of thermal link size, it is concluded that there exists an optimal cool-down time during initial cooling in conduction-cooled superconducting magnet system.

Choi, Yeon Suk; Kim, Dong Lak; Shin, Dong Won

2012-01-01

43

On conduction-cooling of a high-temperature superconducting cable  

NASA Astrophysics Data System (ADS)

Current generation high-temperature superconducting (HTS) power transmission cables use liquid nitrogen as a coolant that circulates along the cable. In this work, the use of axial conduction-cooling in attaining HTS temperatures in transmission lines is proposed. Liquid coolant use is envisioned only at periodic length intervals along the transmission lines, in combination with insulation and copper. The proposed concept is feasible due to the high thermal conductivity of pure copper at cryogenic temperatures. A basic design for the insulated cable is proposed and a detailed numerical simulation of heat transfer in such a cable is carried out for various case studies considering the superconducting materials MgB 2 and BSCCO-2223.

Posada, Alberto; Kim, Young I.; Manousiouthakis, Vasilios

2006-06-01

44

Electromagnetic Phenomena in Superconducting Magnet for Fusion Facility -Pool-Cooled Superconducting Coil-  

NASA Astrophysics Data System (ADS)

The features of superconducting coils for nuclear fusion devices include large size, high field, and high current density. A large conductor is needed for such a large coil to suppress the voltage increase. Since the ability of pool-cooling becomes relatively less with the increase of conductor size, new technologies are necessary to achieve both sufficient mechanical strength and cryogenic stability with high current density. A composite conductor of the 20 kA class was developed for the LHD helical coils. The conductor consists of a pure aluminum stabilizer, a copper sheath, and NbTi/Cu strands. New electromagnetic phenomena, which are Hall current and slow current diffusion into the stabilizer, deteriorate the cryogenic stability. The mechanism and countermeasures are described. Furthermore, a perspective on pool-cooled coils is discussed.

Imagawa, Shinsaku

45

Design analysis of a solid nitrogen cooled “permanent” high-temperature superconducting magnet system  

Microsoft Academic Search

Potential performance advantages of a solid nitrogen cooled “permanent” high-temperature superconducting (SN2\\/HTS) magnet system over a liquid helium cooled low-temperature superconducting (LHe\\/LTS) system are explored. The SN2\\/HTS system design includes a second solid heat capacitor that cools a radiation shield. Recooling of the heat capacitors is performed with a demountable cryocooler. The SN2\\/HTS system offers both enhanced stability and improved

Benjamin J Haid; Haigun Lee; Yukikazu Iwasa; Sang-Soo Oh; Young-Kil Kwon; Kang-Sik Ryu

2002-01-01

46

Experimental validation of advanced regulations for superconducting magnet cooling undergoing periodic heat loads  

SciTech Connect

Superconducting magnets used in tokamaks undergo periodic heat load caused by cycling plasma operations inducing AC losses, neutrons fluxes and eddy currents in magnet structures. In the cryogenic system of JT60-SA tokamak, the Auxiliary Cold Box (ACB) distributes helium from the refrigerator to the cryogenic users and in particular to the superconducting magnets. ACB comprises a saturated helium bath with immersed heat exchangers, extracting heat from independent cooling loops. The supercritical helium flow in each cooling loop is driven by a cold circulator. In order to safely operate the refrigerator during plasma pulses, the interface between the ACB and the refrigerator shall be as stable as possible, with well-balanced bath inlet and outlet mass flows during cycling operation. The solution presented in this paper relies on a combination of regulations to smooth pulsed heat loads and to keep a constant refrigeration power during all the cycle. Two smoothing strategies are presented, both regulating the outlet mass flow of the bath: the first one using the bath as a thermal buffer and the second one storing energy in the loop by varying the cold circulator speed. The bath outlet mass flow is also controlled by an immersed resistive heater which enables a constant evaporation rate in the bath when power coming from the loops is decreasing. The refrigeration power is controlled so that the compensating power remains within an acceptable margin. Experimental validation is achieved using the HELIOS facility. This facility running at CEA Grenoble since 2010 is a scaled down model of the ACB bath and Central Solenoid magnet cooling loop of the JT60-SA tokamak. Test results show performances and robustness of the regulations.

Lagier, B.; Rousset, B.; Hoa, C.; Bonnay, P. [CEA Grenoble INAC/SBT, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

2014-01-29

47

Development of GM Cryocooler-Cooled Bi2223 High Temperature Superconducting Magnetic Separator  

Microsoft Academic Search

We have built a magnetic separator based on the conduction-cooled high temperature superconducting (HTS) magnet. In the paper, the high temperature superconducting magnet is made of Bi-2223 pancakes, and has inner and outer coil diameters of 120 mm and 212 mm and coil height of 111.8 mm. The magnet is conduction-cooled to generate a magnetic field of 3.22 T at

Qiuliang Wang; Yingming Dai; Xinning Hu; Shouseng Song; Yuanzhong Lei; Chuan He; Luguang Yan

2007-01-01

48

Small high cooling power space cooler  

SciTech Connect

The small High Efficiency pulse tube Cooler (HEC) cooler, that has been produced and flown on a number of space infrared instruments, was originally designed to provide cooling of 10 W @ 95 K. It achieved its goal with >50% margin when limited by the 180 W output ac power of its flight electronics. It has also been produced in 2 stage configurations, typically for simultaneously cooling of focal planes to temperatures as low as 35 K and optics at higher temperatures. The need for even higher cooling power in such a low mass cryocooler is motivated by the advent of large focal plane arrays. With the current availability at NGAS of much larger power cryocooler flight electronics, reliable long term operation in space with much larger cooling powers is now possible with the flight proven 4 kg HEC mechanical cooler. Even though the single stage cooler design can be re-qualified for those larger input powers without design change, we redesigned both the linear and coaxial version passive pulse tube cold heads to re-optimize them for high power cooling at temperatures above 130 K while rejecting heat to 300 K. Small changes to the regenerator packing, the re-optimization of the tuned inertance and no change to the compressor resulted in the increased performance at 150 K. The cooler operating at 290 W input power achieves 35 W@ 150 K corresponding to a specific cooling power at 150 K of 8.25 W/W and a very high specific power of 72.5 W/Kg. At these powers the cooler still maintains large stroke, thermal and current margins. In this paper we will present the measured data and the changes to this flight proven cooler that were made to achieve this increased performance.

Nguyen, T. V.; Raab, J.; Durand, D.; Tward, E. [Northrop Grumman Aerospace Systems Redondo Beach, Ca, 90278 (United States)

2014-01-29

49

Investigation of the cooling conditions for the Fast Ramped Superconducting Magnets of the SIS100 Synchrotron  

NASA Astrophysics Data System (ADS)

The dynamic losses in fast ramped super ferric magnets will create the main part of the expected heat losses in the superconducting synchrotron SIS100 - the primary accelerator in the Facility for Antiproton and Ion Research (FAIR). The data measured on dipole models at the cryogenic magnet test facility at GSI allow to predict the static and dynamic losses in the superconducting magnets for different operation modes of the SIS100 synchrotron. The calculations of the expected mass flow rates in the cooling channels of the superconducting magnets together with the analysis of the cooling system for different operation modes of the synchrotron will be presented.

Bleile, A.; Fischer, E.; Khodzhibagiyan, H.; Mireau, A.; Schnizer, P.

2014-05-01

50

Power electronics substrate for direct substrate cooling  

DOEpatents

Systems and apparatus are provided for power electronics substrates adapted for direct substrate cooling. A power electronics substrate comprises a first surface configured to have electrical circuitry disposed thereon, a second surface, and a plurality of physical features on the second surface. The physical features are configured to promote a turbulent boundary layer in a coolant impinged upon the second surface.

Le, Khiet (Mission Viejo, CA); Ward, Terence G. (Redondo Beach, CA); Mann, Brooks S. (Redondo Beach, CA); Yankoski, Edward P. (Corona, CA); Smith, Gregory S. (Woodland Hills, CA)

2012-05-01

51

Installation Schemes of Superconducting Generators in Power Systems  

Microsoft Academic Search

Superconducting generator (SCG) with superconducting field winding has many advantages such as small size, light weight, high generation efficiency. In particular, the property of low synchronous reactances, which is not realized in conventional generators, is able to improve power system stability. Installation scheme of SCGs in multi-machine power system becomes one of the topics that should be considered. It concerns

Worawut Sae-Kok; Akihiko Yokoyama

2007-01-01

52

Design of A Conduction-cooled 4T Superconducting Racetrack for Multi-field Coupling Measurement System  

E-print Network

A conduction-cooled superconducting magnet producing a transverse field of 4 Tesla has been designed for the new generation multi-field coupling measurement system, which was used to study the mechanical behavior of superconducting samples at cryogenic temperature and intense magnetic fields. Considering experimental costs and coordinating with system of strain measurements by contactless signals (nonlinear CCD optics system), the racetrack type for the coil winding was chosen in our design, and a compact cryostat with a two-stage GM cryocooler was designed and manufactured for the superconducting magnet. The magnet was composed of a pair of flat racetrack coils wound by NbTi/Cu superconducting composite wires, a copper and stainless steel combinational form and two Bi2Sr2CaCu2Oy superconducting current leads. All the coils were connected in series and can be powered with a single power supply. The maximum central magnetic field is 4 T. In order to support the high stress and uniform thermal distribution in t...

Chen, Yuquan; Wu, Wei; Guan, Mingzhi; Wu, Beimin; Mei, Enming; Xin, Canjie

2015-01-01

53

Effect of evenly spaced channels on the stability behaviour of superconducting windings cooled by superfluid helium  

SciTech Connect

Stability tests on channel cooled superconducting windings have revealed the existence of stationary normal zones as a possible response to transient disturbances. Solutions obtained by the time-independent heat equation of a conductor cooled with unsaturated superfluid helium are given, along with a model which confirms the existence of stable states with more or less extended normal zones in well defined regions of the I-B plane. It is concluded that stability of superconducting magnets should be evaluated by taking into account the absolute values given to the lengths of cooled and uncooled conductor sections rather than the average wetted conductor surface. 6 refs.

Seyfert, P.; McCall, M.J.; Claudet, G.; Meuris, C.

1981-09-01

54

Superconductive energy storage inductor-converter units for power systems  

Microsoft Academic Search

Large magnets with superconductive windings could serve to perform a power system function analogous to pumped storage hydro. A conventional Graetz bridge converter as used in dc transmission provides an ideal interface between the three-phase power system and the superconductive magnet or inductor. Such Inductor-Converter or I-C units, when properly controlled, provide significant power system benefits. Power reversibility is achievable

H. A. Peterson; N. Mohan; R. W. Boom

1975-01-01

55

Cryogenic System for a High Temperature Superconducting Power Transmission Cable  

SciTech Connect

High-temperature superconducting (HTS) cable systems for power transmission are under development that will use pressurized liquid nitrogen to provide cooling of the cable and termination hardware. Southwire Company and Oak Ridge National Laboratory have been operating a prototype HTS cable system that contains many of the typical components needed for a commercial power transmission application. It is being used to conduct research in the development of components and systems for eventual commercial deployment. The cryogenic system was built by Air Products and Chemicals, Allentown, Pennsylvania, and can circulate up to 0.35 kg/s of liquid nitrogen at temperatures as low as 67 K at pressures of 1 to 10 bars. Sufficient cooling is provided for testing a 5-m-long HTS transmission cable system that includes the terminations required for room temperature electrical connections. Testing of the 5-m HTS transmission cable has been conducted at the design ac conditions of 1250 A and 7.5 kV line to ground. This paper contains a description of the essential features of the HTS cable cryogenic system and performance results obtained during operation of the system. The salient features of the operation that are important in large commercial HTS cable applications will be discussed.

Demko, J.A.; Gouge, M.J.; Hughey, R.L.; Lue, J.W.; Martin, R.; Sinha, U.; Stovall, J.P.

1999-07-12

56

Cooling of Compact Stars with Quark-Hadron Mixed Phase in the Colour Superconductive State  

NASA Astrophysics Data System (ADS)

Recently, the central source of Cassiopeia A (Cas A) has been observed, which indicates that the star has large mass and high effective temperature. We suspect that the compact object cools by the standard neutrino emission. We assume that the compact object contains quark matter with colour superconductivity and calculate cooling curves. Considering the Quark-Hadron Mixed Phase, we obtain cooling curves which are found to be consistent with the observations.

Noda, Tsuneo; Hashimoto, Masa-Aki; Yasutake, Nobutoshi; Maruyama, Toshiki; Tatsumi, Toshitaka; Fujimoto, Masayuki

2010-08-01

57

Direct-Cooled Power Electronics Substrate  

SciTech Connect

The goal of the Direct-Cooled Power Electronics Substrate project is to reduce the size and weight of the heat sink for power electronics used in hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs). The concept proposed in this project was to develop an innovative power electronics mounting structure, model it, and perform both thermal and mechanical finite-element analysis (FEA). This concept involved integrating cooling channels within the direct-bonded copper (DBC) substrate and strategically locating these channels underneath the power electronic devices. This arrangement would then be directly cooled by water-ethylene glycol (WEG), essentially eliminating the conventional heat sink and associated heat flow path. The concept was evaluated to determine its manufacturability, its compatibility with WEG, and the potential to reduce size and weight while directly cooling the DBC and associated electronics with a coolant temperature of 105 C. This concept does not provide direct cooling to the electronics, only direct cooling inside the DBC substrate itself. These designs will take into account issues such as containment of the fluid (separation from the electronics) and synergy with the whole power inverter design architecture. In FY 2008, mechanical modeling of substrate and inverter core designs as well as thermal and mechanical stress FEA modeling of the substrate designs was performed, along with research into manufacturing capabilities and methods that will support the substrate designs. In FY 2009, a preferred design(s) will be fabricated and laboratory validation testing will be completed. In FY 2010, based on the previous years laboratory testing, the mechanical design will be modified and the next generation will be built and tested in an operating inverter prototype.

Wiles, R.; Ayers, C.; Wereszczak, A.

2008-12-23

58

Potential Refrigerants for Power Electronics Cooling  

SciTech Connect

In the past, automotive refrigerants have conventionally been used solely for the purpose of air conditioning. However, with the development of hybrid-electric vehicles and the incorporation of power electronics (PEs) into the automobile, automotive refrigerants are taking on a new role. Unfortunately, PEs have lifetimes and functionalities that are highly dependent on temperature and as a result thermal control plays an important role in the performance of PEs. Typically, PEs are placed in the engine compartment where the internal combustion engine (ICE) already produces substantial heat. Along with the ICE heat, the additional thermal energy produced by PEs themselves forces designers to use different cooling methods to prevent overheating. Generally, heat sinks and separate cooling loops are used to maintain the temperature. Disturbingly, the thermal control system can consume one third of the total volume and may weigh more than the PEs [1]. Hence, other avenues have been sought to cool PEs, including submerging PEs in automobile refrigerants to take advantage of two-phase cooling. The objective of this report is to explore the different automotive refrigerants presently available that could be used for PE cooling. Evaluation of the refrigerants will be done by comparing environmental effects and some thermo-physical properties important to two-phase cooling, specifically measuring the dielectric strengths of potential candidates. Results of this report will be used to assess the different candidates with good potential for future use in PE cooling.

Starke, M.R.

2005-10-24

59

Heat pipe cooling of power processing magnetics  

NASA Technical Reports Server (NTRS)

The constant demand for increased power and reduced mass has raised the internal temperature of conventionally cooled power magnetics toward the upper limit of acceptability. The conflicting demands of electrical isolation, mechanical integrity, and thermal conductivity preclude significant further advancements using conventional approaches. However, the size and mass of multikilowatt power processing systems may be further reduced by the incorporation of heat pipe cooling directly into the power magnetics. Additionally, by maintaining lower more constant temperatures, the life and reliability of the magnetic devices will be improved. A heat pipe cooled transformer and input filter have been developed for the 2.4 kW beam supply of a 30-cm ion thruster system. This development yielded a mass reduction of 40% (1.76 kg) and lower mean winding temperature (20 C lower). While these improvements are significant, preliminary designs predict even greater benefits to be realized at higher power. This paper presents the design details along with the results of thermal vacuum operation and the component performance in a 3 kW breadboard power processor.

Hansen, I. G.; Chester, M.

1979-01-01

60

Application of Superconducting Power Cables to DC Electric Railway Systems  

NASA Astrophysics Data System (ADS)

For novel design and efficient operation of next-generation DC electric railway systems, especially for their substantial energy saving, we have studied the feasibility of applying superconducting power cables to them. In this paper it is assumed that a superconducting power cable is applied to connect substations supplying electric power to trains. An analysis model line was described by an electric circuit, which was analyzed with MATLAB-Simulink. From the calculated voltages and currents of the circuit, the regenerative brake and the energy losses were estimated. In addition, assuming the heat loads of superconducting power cables and the cryogenic efficiency, the energy saving of the total system was evaluated. The results show that the introduction of superconducting power cables could achieve the improved use of regenerative brake, the loss reduction, the decreased number of substations, the reduced maintenance, etc.

Ohsaki, Hiroyuki; Lv, Zhen; Sekino, Masaki; Tomita, Masaru

61

Hybrid Wet/Dry Cooling for Power Plants (Presentation)  

SciTech Connect

This presentation includes an overview of cooling options, an analysis of evaporative enhancement of air-cooled geothermal power plants, field measurements at a geothermal plant, a preliminary analysis of trough plant, and improvements to air-cooled condensers.

Kutscher, C.; Buys, A.; Gladden, C.

2006-02-01

62

Steam-Electric Power-Plant-Cooling Handbook  

SciTech Connect

The Steam-Electric Power Plant Cooling Handbook provides summary data on steam-electric power plant capacity, generation and number of plants for each cooling means, by Electric Regions, Water Resource Regions and National Electric Reliability Council Areas. Water consumption by once-through cooling, cooling ponds and wet evaporative towers is discussed and a methodology for computation of water consumption is provided for a typical steam-electric plant which uses a wet evaporative tower or cooling pond for cooling.

Sonnichsen, J.C.; Carlson, H.A.; Charles, P.D.; Jacobson, L.D.; Tadlock, L.A.

1982-02-01

63

ON THE LOW-FIELD Q-SLOPE OF RF SUPERCONDUCTING NIOBIUM CAVITIES COOLED BY HELIUM-I  

E-print Network

ON THE LOW-FIELD Q-SLOPE OF RF SUPERCONDUCTING NIOBIUM CAVITIES COOLED BY HELIUM-I R. L. Gengy , H Experimental measurements have consistently shown that RF superconducting Niobium cavities cooled by He- I of Niobium cavities and liquid Helium. Thermal modeling of Niobium cavi- ties is performed in this paper

Geng, Rong-Li

64

Electric properties of a 66 kV 3-core superconducting power cable system  

Microsoft Academic Search

A 100 m-long, 66 kV, 3-core high temperature superconducting power cable system prototype has been developed and installed in order to verify its properties and performance for practical use. The cable is a cold dielectric type with three cable-cores placed in co-axial stainless corrugated pipes. After cooling the cable to LN2 temperature, long duration tests, such as that for nominal

Shoichi Honjo; Masato Shimodate; Yoshihisa Takahashi; Takato Masuda; Hiroyasu Yumura; Chizuru Suzawa; Shigeki Isojima; Hiroshi Suzuki

2003-01-01

65

Hydrogen cooling options for MgB{sub 2}-based superconducting systems  

SciTech Connect

With the arrival of MgB{sub 2} for low-cost superconducting magnets, hydrogen cooling has become an interesting alternative to costly liquid helium. Hydrogen is generally regarded as the most efficient coolant in cryogenics and, in particular, is well suited for cooling superconducting magnets. Cooling methods need to take into account the specific quench propagation in the MgB{sub 2} magnet winding and facilitate a cryogenically reliable and safe cooling environment. The authors propose three different multi-coolant options for MRI scanners using helium or hydrogen within the same design framework. Furthermore, a design option for whole-body scanners which employs technology, components, fueling techniques and safety devices from the hydrogen automotive industry is presented, continuing the trend towards replacing helium with hydrogen as a safe and cost efficient coolant.

Stautner, W.; Xu, M.; Mine, S.; Amm, K. [Electromagnetics and Superconductivity Lab, GE Global Research, Niskayuna, NY 12309 (United States)

2014-01-29

66

Hydrogen cooling options for MgB2-based superconducting systems  

NASA Astrophysics Data System (ADS)

With the arrival of MgB2 for low-cost superconducting magnets, hydrogen cooling has become an interesting alternative to costly liquid helium. Hydrogen is generally regarded as the most efficient coolant in cryogenics and, in particular, is well suited for cooling superconducting magnets. Cooling methods need to take into account the specific quench propagation in the MgB2 magnet winding and facilitate a cryogenically reliable and safe cooling environment. The authors propose three different multi-coolant options for MRI scanners using helium or hydrogen within the same design framework. Furthermore, a design option for whole-body scanners which employs technology, components, fueling techniques and safety devices from the hydrogen automotive industry is presented, continuing the trend towards replacing helium with hydrogen as a safe and cost efficient coolant.

Stautner, W.; Xu, M.; Mine, S.; Amm, K.

2014-01-01

67

Calculation of the pressure rise in the cooling tube of a two-phase cooling system during a quench of an indirectly cooled superconducting magnet  

NASA Astrophysics Data System (ADS)

Large superconducting detector magnets are indirectly cooled with two-phase helium flowing in cooling tubes attached to the coil or its support structure. Large detector magnets often quench such that most of the magnet stored energy ends up as heat stored in the coil package. The time constant for energy deposition in the coil and support structure is often quite short. This paper presents a method for calculating the peak pressure rise in the magnet two-phase cooling tube during a magnet quench. A comparison of calculated peak pressure rise and measured pressure rise for the PEP-4 solenoid is presented in this report.

Green, M. A.

1994-07-01

68

Polk power station syngas cooling system  

SciTech Connect

Tampa Electric Company (TEC) is in the site development and construction phase of the new Polk Power Station Unit No. 1. This will be the first unit at a new site and will use Integrated Gasification Combined Cycle (IGCC) Technology. The unit will utilize Texaco`s oxygen-blown, entrained-flow coal gasification, along with combined cycle power generation, to produce nominal 260MW. Integral to the gasification process is the syngas cooling system. The design, integration, fabrication, transportation, and erection of this equipment have provided and continue to provide major challenges for this project.

Jenkins, S.D.

1995-01-01

69

Heat pipe cooling of power processing magnetics  

NASA Technical Reports Server (NTRS)

A heat pipe cooled transformer and input filter were developed for the 2.4 kW beam supply of a 30 cm ion thruster system. This development yielded a mass reduction of 40% (1.76 kg) and lower mean winding temperature (20 C lower). While these improvements are significant, preliminary designs predict even greater benefits to be realized at higher power. The design details are presented along with the results of thermal vacuum operation and the component performance in a 3 kW breadboard power processor.

Hansen, I. G.; Chester, M. S.

1979-01-01

70

Power conditioning systems for superconductive magnetic energy storage  

Microsoft Academic Search

Two power conditioning systems for superconductive magnetic energy storage (SMES) are presented. One power conditioning system is based on a hybrid current sourced inverter (CSI), the second is a combination of a DC chopper with a voltage sourced inverter (VSI). Both of these systems have independent control of real and reactive power. These systems have a significant reduction in MVA

R. H. Lasseter; S. G. Jalali

1991-01-01

71

The Application of High Temperature Superconducting Materials to Power Switches  

E-print Network

Superconducting switches may find application in superconducting magnet systems that require energy extraction. Such superconducting switches could be bypass-switches that are operated in conjunction with a parallel resistor or dump-switches where all of the energy is dissipated in the switch itself. Bypass-switches are more suited to higher energy circuits as a portion of the energy can be dissipated in the external dump resistor. Dump- switches require less material and triggering energy as a lower switch resistance is needed to achieve the required total dump resistance. Both superconducting bypass-switches and superconducting dump-switches can be ther- mally activated. Switching times that are comparable to those obtained with mechanical bypass-switch systems can be achieved using a co-wound heater that is powered by a ca- pacitor discharge. Switches that have fast thermal diffusion times through the insulation can be modelled as a lumped system whereas those with slow thermal diffusion times were modelle...

March, S A; Ballarino, A

2009-01-01

72

High-Tc superconducting materials for electric power applications  

Microsoft Academic Search

Large-scale superconducting electric devices for power industry depend critically on wires with high critical current densities at temperatures where cryogenic losses are tolerable. This restricts choice to two high-temperature cuprate superconductors, (Bi,Pb)2Sr2Ca2Cu3Ox and YBa2Cu3Ox, and possibly to MgB2, recently discovered to superconduct at 39 K. Crystal structure and material anisotropy place fundamental restrictions on their properties, especially in polycrystalline form.

David Larbalestier; Alex Gurevich; D. Matthew Feldmann; Anatoly Polyanskii

2001-01-01

73

Cooling of Compact Stars with Color Superconducting Phase in Quark-hadron Mixed Phase  

NASA Astrophysics Data System (ADS)

We present a new scenario for the cooling of compact stars considering the central source of Cassiopeia A (Cas A). The Cas A observation shows that the central source is a compact star that has high effective temperature, and it is consistent with the cooling without exotic phases. The observation also gives the mass range of M >= 1.5 M ?, which may conflict with the current plausible cooling scenario of compact stars. There are some cooled compact stars such as Vela or 3C58, which can barely be explained by the minimal cooling scenario, which includes the neutrino emission by nucleon superfluidity (PBF). Therefore, we invoke the exotic cooling processes, where a heavier star cools faster than lighter one. However, the scenario seems to be inconsistent with the observation of Cas A. Therefore, we present a new cooling scenario to explain the observation of Cas A by constructing models that include a quark color superconducting (CSC) phase with a large energy gap; this phase appears at ultrahigh density regions and reduces neutrino emissivity. In our model, a compact star has a CSC quark core with a low neutrino emissivity surrounded by high emissivity region made by normal quarks. We present cooling curves obtained from the evolutionary calculations of compact stars: while heavier stars cool slowly, and lighter ones indicate the opposite tendency without considering nucleon superfluidity. Furthermore, we show that our scenario is consistent with the recent observations of the effective temperature of Cas A during the last 10 years, including nucleon superfluidity.

Noda, Tsuneo; Hashimoto, Masa-aki; Yasutake, Nobutoshi; Maruyama, Toshiki; Tatsumi, Toshitaka; Fujimoto, Masayuki

2013-03-01

74

Operational Experience with the LHC Superconducting Links and Evaluation of Possible Cryogenic Schemes for Future Remote Powering of Superconducting Magnets  

E-print Network

In the LHC, a large number of superconducting magnets are powered remotely by 5 superconducting links at distances of 70 up to 520 m. This innovation allowed choosing more convenient locations for installing the electrical feedboxes and their related equipment. The consolidations performed after the first commissioning campaign and the operational experience with the superconducting links over a period of several months are presented. Based on the successful application of superconducting links in the LHC, such devices can be envisaged for powering future accelerator magnets. Several possible cryogenic configurations for future superconducting links are presented with their respective figures of merit from the cryogenic and practical implementation point of view.

Perin, A; Claudet, S

2010-01-01

75

Thermal management of high power dissipation electronic packages: from air cooling to liquid cooling  

Microsoft Academic Search

Performance-driven electronic packaging demands for thermal solutions of high power dissipation such as enhanced air cooling or, alternatively, liquid cooling technologies. This paper reports the characterization of air-cooled vapor chamber heat sink (VCHS) and liquid cooled heat sinks (LCHS) for electronic packages with a targeted power dissipation of 140W. The test vehicle flip chip plastic BGA package (FC-PBGA) involves a

H. Y. Zhang; D. Pinjala; Poi-Siong Teo

2003-01-01

76

Power converter having improved fluid cooling  

DOEpatents

A 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, which may be controlled in a closed-loop manner. Interfacing between circuits, circuit mounting structure, and the support provide for greatly enhanced cooling. The support may form 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.

Meyer, Andreas A.; Radosevich, Lawrence D.; Beihoff, Bruce C.; Kehl, Dennis L.; Kannenberg, Daniel G.

2007-03-06

77

Study of high field superconducting solenoids for muon beam cooling  

SciTech Connect

The final beam cooling stages of a possible Muon Collider may require DC solenoid magnets with magnetic fields of 40-50 T in an aperture of 40-50 mm. In this paper we study possible solutions towards creating DC fields of that order using available superconductors. Several magnetic and mechanical designs, optimized for the maximum performance are presented and compared in terms of cost and size.

Kashikhin, V.V.; Barzi, E.; Kashikhin, V.S.; Lamm, Michael J.; /FERMILAB; Sadovskiy, Y.; /Moscow Phys. Eng. Inst.; Zlobin, Alexander V; /Fermilab

2007-08-01

78

A multilevel power conditioning system for superconductive magnetic energy storage  

Microsoft Academic Search

The introduction of multilevel converters makes possible the use of pulse width modulation (PWM) converters and fast switching medium power devices like insulated gate bipolar transistors (IGBTs) for high-voltage, high-power applications, such as flexible ac transmission systems (FACTS). This paper proposes a five-level voltage source inverter (VSI)-chopper for a superconductive magnetic energy storage (SMES) power conditioning system (PCS). The circuit

Hui Li; Thomas L. Baldwin; Cesar A. Luongo; Da Zhang

2005-01-01

79

Liquid Metal Cooled Reactor for Space Power  

NASA Astrophysics Data System (ADS)

The conceptual design is for a liquid metal (LM) cooled nuclear reactor that would provide heat to a closed Brayton cycle (CBC) power conversion subsystem to provide electricity for electric propulsion thrusters and spacecraft power. The baseline power level is 100 kWe to the user. For long term power generation, UN pin fuel with Nb1Zr alloy cladding was selected. As part of the SP-100 Program this fuel demonstrated lifetime with greater than six atom percent burnup, at temperatures in the range of 1400-1500 K. The CBC subsystem was selected because of the performance and lifetime database from commercial and aircraft applications and from prior NASA and DOE space programs. The high efficiency of the CBC also allows the reactor to operate at relatively low power levels over its 15-year life, minimizing the long-term power density and temperature of the fuel. The scope of this paper is limited to only the nuclear components that provide heated helium-xenon gas to the CBC subsystem. The principal challenge for the LM reactor concept was to design the reactor core, shield and primary heat transport subsystems to meet mission requirements in a low mass configuration. The LM concept design approach was to assemble components from prior programs and, with minimum change, determine if the system met the objective of the study. All of the components are based on technologies having substantial data bases. Nuclear, thermalhydraulic, stress, and shielding analyses were performed using available computer codes. Neutronics issues included maintaining adequate operating and shutdown reactivities, even under accident conditions. Thermalhydraulic and stress analyses calculated fuel and material temperatures, coolant flows and temperatures, and thermal stresses in the fuel pins, components and structures. Using conservative design assumptions and practices, consistent with the detailed design work performed during the SP-100 Program, the mass of the reactor, shield, primary heat transport, reactor instrument and control, and additional structure totaled approximately 1100 kg.

Weitzberg, Abraham

2003-01-01

80

Grain-aligned YBCO superconducting current leads for conduction-cooled applications  

Microsoft Academic Search

Grain-aligned YBCO superconductors have been developed for use in a conduction-cooled, cryogen-free superconducting magnet application. A magnetic alignment technique has been used to orient the c-axis of the YBCO grains. Current leads 0.3×1.4×6.4 cm were fabricated and thermally connected between the first and second stage of a Gifford-McMahon cryocooler. The heat conduction down the leads was determined from a load

K. G. Herd; B. Dorri; E. T. Laskaris; J. E. Tkaczyk; K. W. Lay

1993-01-01

81

THE ROLE OF AGING AND ONCE-THROUGH-COOLED POWER  

E-print Network

................................................................29 Los Angeles Basin--Los Angeles Department of Water and Power Control Area .........35 Big CreekCALIFORNIA ENERGY COMMISSION THE ROLE OF AGING AND ONCE-THROUGH-COOLED POWER PLANTS IN CALIFORNIA Nyberg, Darryl Metz, Connie Leni. 2009. The Role of Aging and Once-Through-Cooled Power Plants

82

Performance Analysis of XCPC Powered Solar Cooling Demonstration Project  

NASA Astrophysics Data System (ADS)

A solar thermal cooling system using novel non-tracking External Compound Parabolic Concentrators (XCPC) has been built at the University of California, Merced and operated for two cooling seasons. Its performance in providing power for space cooling has been analyzed. This solar cooling system is comprised of 53.3 m2 of XCPC trough collectors which are used to power a 23 kW double effect (LiBr) absorption chiller. This is the first system that combines both XCPC and absorption chilling technologies. Performance of the system was measured in both sunny and cloudy conditions, with both clean and dirty collectors. It was found that these collectors are well suited at providing thermal power to drive absorption cooling systems and that both the coinciding of available thermal power with cooling demand and the simplicity of the XCPC collectors compared to other solar thermal collectors makes them a highly attractive candidate for cooling projects.

Widyolar, Bennett K.

83

COOLING OF COMPACT STARS WITH COLOR SUPERCONDUCTING PHASE IN QUARK-HADRON MIXED PHASE  

SciTech Connect

We present a new scenario for the cooling of compact stars considering the central source of Cassiopeia A (Cas A). The Cas A observation shows that the central source is a compact star that has high effective temperature, and it is consistent with the cooling without exotic phases. The observation also gives the mass range of M {>=} 1.5 M {sub Sun }, which may conflict with the current plausible cooling scenario of compact stars. There are some cooled compact stars such as Vela or 3C58, which can barely be explained by the minimal cooling scenario, which includes the neutrino emission by nucleon superfluidity (PBF). Therefore, we invoke the exotic cooling processes, where a heavier star cools faster than lighter one. However, the scenario seems to be inconsistent with the observation of Cas A. Therefore, we present a new cooling scenario to explain the observation of Cas A by constructing models that include a quark color superconducting (CSC) phase with a large energy gap; this phase appears at ultrahigh density regions and reduces neutrino emissivity. In our model, a compact star has a CSC quark core with a low neutrino emissivity surrounded by high emissivity region made by normal quarks. We present cooling curves obtained from the evolutionary calculations of compact stars: while heavier stars cool slowly, and lighter ones indicate the opposite tendency without considering nucleon superfluidity. Furthermore, we show that our scenario is consistent with the recent observations of the effective temperature of Cas A during the last 10 years, including nucleon superfluidity.

Noda, Tsuneo; Hashimoto, Masa-aki [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581 Japan (Japan)] [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka, 812-8581 Japan (Japan); Yasutake, Nobutoshi [Research Center for the Early Universe, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)] [Research Center for the Early Universe, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Maruyama, Toshiki [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan)] [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Tatsumi, Toshitaka [Department of Physics, Kyoto University, Kitashirakawa-Oiwake-cho, Kyoto 606-8502 (Japan)] [Department of Physics, Kyoto University, Kitashirakawa-Oiwake-cho, Kyoto 606-8502 (Japan); Fujimoto, Masayuki, E-mail: tsune@phys.kyushu-u.ac.jp, E-mail: hashimoto@phys.kyushu-u.ac.jp [Department of Physics, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0810 (Japan)] [Department of Physics, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0810 (Japan)

2013-03-01

84

Hybrid Cooling Systems for Low-Temperature Geothermal Power Production  

SciTech Connect

This paper describes the identification and evaluation of methods by which the net power output of an air-cooled geothermal power plant can be enhanced during hot ambient conditions with a minimal amount of water use.

Ashwood, A.; Bharathan, D.

2011-03-01

85

Installation Schemes of Superconducting Generators in Power Systems  

NASA Astrophysics Data System (ADS)

Superconducting generator (SCG) with superconducting field winding has many advantages such as small size, light weight, high generation efficiency. In particular, the property of low synchronous reactances, which is not realized in conventional generators, is able to improve power system stability. Installation scheme of SCGs in multi-machine power system becomes one of the topics that should be considered. It concerns how and where SCGs should be installed and parameters setting of machines and controllers. New methods for determining the optimal locations and machine parameters such as synchronous reactance Xd of SCG and control parameters based on approximated eigenvalue sensitivity and genetic algorithms for improving dynamic stability are proposed in this paper. Effectiveness of those methods are verified in IEEJ East 10-machine and it is shown that the proposed methods are effective installation schemes for improving power system stability.

Sae-Kok, Worawut; Yokoyama, Akihiko

86

Inverter power module with distributed support for direct substrate cooling  

DOEpatents

Systems and/or methods are provided for an inverter power module with distributed support for direct substrate cooling. An inverter module comprises a power electronic substrate. A first support frame is adapted to house the power electronic substrate and has a first region adapted to allow direct cooling of the power electronic substrate. A gasket is interposed between the power electronic substrate and the first support frame. The gasket is configured to provide a seal between the first region and the power electronic substrate. A second support frame is adapted to house the power electronic substrate and joined to the first support frame to form the seal.

Miller, David Harold (San Pedro, CA); Korich, Mark D. (Chino Hills, CA); Ward, Terence G. (Redondo Beach, CA); Mann, Brooks S. (Redondo Beach, CA)

2012-08-21

87

Case study on the US superconducting power transmission program  

SciTech Connect

After the 1911 discovery of superconductivity (the abrupt loss of electrical resistance in certain materials at very low temperatures), attempts were made to make practical use of this phenomenon. Initially these attempts failed, but in the early 1960s (after 50 years of research) they succeeded. By then, the projected growth in the production and consumption of electrical energy required much higher capacity power transmission capabilities than were available or likely to become available from incremental improvements in existing transmission technology. Since superconductors were capable in principle of transmitting huge amounts of power, research programs to develop and demonstrate superconducting transmission lines were initiated in the US and abroad. The history of the US program, including the participants, their objectives, funding and progress made, is outlined. Since the R&D program was terminated before the technology was completely demonstrated, the reasons for and consequences of this action are discussed in a final section.

Hammel, E.F.

1996-02-01

88

Studies of power conditioning circuits for superconductive magnetic energy store  

Microsoft Academic Search

The superconductive magnetic energy store (SMES) approach to utility-load leveling has the potential for very high energy conversion efficiency and fast response to changes in load demands. It can be used to improve utility system operation economics and system stabilities. The power-conditioning circuit interfacing an SMES and a utility network consists of thyristor or gate-turn-off (GTO) device bridges of the

J. Wang; J. Skiles; R. Kustom; T. Ise; F. Tsang; J. Cleary

1988-01-01

89

Assessment of Evaporative Cooling Enhancement Methods for Air-Cooled Geothermal Power Plants: Preprint  

Microsoft Academic Search

Many binary-cycle geothermal power plants are air cooled because insufficient water is available to provide year-round water cooling. The performance of air-cooled geothermal plants is highly dependent on the dry bulb temperature of the air (much more so than fossil fuel plants that operate at higher boiler temperatures), and plant electric output can drop by 50% or more on hot

C. Kutscher; D. Costenaro

2002-01-01

90

78 FR 35330 - Initial Test Programs for Water-Cooled Nuclear Power Plants  

Federal Register 2010, 2011, 2012, 2013, 2014

...Water-Cooled Nuclear Power Plants.'' This guide describes...water cooled nuclear power plants. ADDRESSES: Please...series. This series was developed to describe and make...water cooled nuclear power plants. This RG is being...

2013-06-12

91

77 FR 73056 - Initial Test Programs for Water-Cooled Nuclear Power Plants  

Federal Register 2010, 2011, 2012, 2013, 2014

...Water-Cooled Nuclear Power Plants.'' This guide...cooled nuclear power plants. DATES: Submit...currently being developed or improvements...This series was developed to describe and...Water-Cooled Nuclear Power Plants,'' is...

2012-12-07

92

Superconducting electromechanical rotating device having a liquid-cooled, potted, one layer stator winding  

DOEpatents

A superconducting electromechanical rotating (SER) device, such as a synchronous AC motor, includes a superconducting field winding and a one-layer stator winding that may be water-cooled. The stator winding is potted to a support such as the inner radial surface of a support structure and, accordingly, lacks hangers or other mechanical fasteners that otherwise would complicate stator assembly and require the provision of an unnecessarily large gap between adjacent stator coil sections. The one-layer winding topology, resulting in the number of coils being equal to half the number of slots or other mounting locations on the support structure, allows one to minimize or eliminate the gap between the inner radial ends of adjacent straight sections of the stator coilswhile maintaining the gap between the coil knuckles equal to at least the coil width, providing sufficient room for electrical and cooling element configurations and connections. The stator winding may be potted to the support structure or other support, for example, by a one-step VPI process relying on saturation of an absorbent material to fill large gaps in the stator winding or by a two-step process in which small gaps are first filled via a VPI or similar operation and larger gaps are then filled via an operation that utilizes the stator as a portion of an on-site mold.

Dombrovski, Viatcheslav V. (Willoughby Hills, OH); Driscoll, David I. (South Euclid, OH); Shovkhet, Boris A. (Beachwood, OH)

2001-01-01

93

Development of a solar-powered passive ejector cooling system  

Microsoft Academic Search

This paper describes the development of an ejector refrigeration system that is powered by solar thermal energy. The cooling system contains no active parts and is therefore deemed passive. Water is used as the refrigerant though other natural refrigerants could be used for lower temperature operation. A prototype system was built with a nominal cooling capacity of 7 kW. This

V. M Nguyen; S. B Riffat; P. S Doherty

2001-01-01

94

Laboratory research on combined cooling, heating and power (CCHP) systems  

Microsoft Academic Search

Combined cooling, heating and power (CCHP) systems offer the potential for a significant increase in fuel use efficiency by generating electricity onsite and recycling the exhaust gas for heating, cooling, or dehumidifying. A challenge for CCHP system is the efficient integration of distributed generation (DG) equipment with thermally-activated (TA) technologies. The China Ministry of Science and Technology and Tsinghua University

L. Fu; X. L. Zhao; S. G. Zhang; Y. Jiang; H. Li; W. W. Yang

2009-01-01

95

Design of de-ionised water cooling of power converters  

Microsoft Academic Search

Power electronics converters need cooling devices. High thermal performances allows decrease of converter volume and cost, and have a major impact on long-term reliability. Semiconductors encapsulation structure have to combine two opposite requirements, namely low thermal resistance and electrical insulation capabilities. Among numbers of designs (ceramics, diamond, polymers etc.), dielectric fluid cooling has been used for high voltage applications (oil,

E. Ramchy; B. Malinowska; M. Cassir

1998-01-01

96

Winding, cooling and initial testing of a 10 H superconducting MgB2 coil for an induction heater  

NASA Astrophysics Data System (ADS)

A 10 H superconducting MgB2 coil, suitable for an induction heating application, has been wound, cooled and initially tested. Eight kilometres of MgB2 tape were first insulated and then wound into double pancake coils before being assembled into the complete coil. The process is described in detail, focusing on hands-on experience gained, especially regarding the different steps in the wet-winding technique used. The insulation, soldering, winding and cooling techniques applied proved practical for manufacturing of the large MgB2 coil. The complete coil was cooled by conduction cooling to 8 K and tested with a current of 185 A.

Sætre, F.; Hiltunen, I.; Runde, M.; Magnusson, N.; Järvelä, J.; Bjerkli, J.; Engebrethsen, E.

2011-03-01

97

Interconnected Power Systems with Superconducting Magnetic Energy Storage  

NASA Astrophysics Data System (ADS)

The objective of this work is to discuss the concept of back-to-back interconnection systems with energy storage, especially with a Superconducting Magnetic Energy Storage (SMES) incorporated into a back-to-back DC link. In this case, each converter of the back-to-back system is used as a power conditioning system for the SMES coils. Since the AC/DC converter can be designed independently of the frequency of the power system, a two-way switch is connected to the AC side of each converter. This two-way switch can select the interconnected power systems. By using the two-way switches, this system can provide the stored energy in the SMES system to each interconnected power system through two AC/DC converters. For instance, lower-cost power of each power network can be stored through two converters during the off-peak hours and made available for dispatch to each power network during periods of demand peak. Then this system increases the reliability of electric power networks and enables the economical operations depending on the power demand. This paper describes the unique operations of the back-to-back interconnection with SMES and discusses the optimal SMES configuration for a 300-MW class back-to-back interconnection.

Nomura, Shinichi; Hagita, Takushi; Tsutsui, Hiroaki; Sato, Yoshihisa; Shimada, Ryuichi

98

Cryogenic cooling for high power laser amplifiers  

NASA Astrophysics Data System (ADS)

Using DPSSL (Diode Pumped Solid State Lasers) as pumping technology, PW-class lasers with enhanced repetition rates are developed. Each of the Yb YAG amplifiers will be diode-pumped at a wavelength of 940 nm. This is a prerequisite for achieving high repetition rates (light amplification duration 1 millisecond and repetition rate 10 Hz). The efficiency of DPSSL is inversely proportional to the temperature, for this reason the slab amplifier have to be cooled at a temperature in the range of 100 K-170 K with a heat flux of 1 MW*m-2. This paper describes the thermo-mechanical analysis for the design of the amplification laser head, presents a preliminary proposal for the required cryogenic cooling system and finally outlines the gain of cryogenic operation for the efficiency of high pulsed laser.

Perin, J. P.; Millet, F.; Divoky, M.; Rus, B.

2013-11-01

99

Conductor requirements for high-temperature superconducting utility power transformers  

SciTech Connect

High-temperature superconducting (HTS) coated conductors in utility power transformers must satisfy a set of operating requirements that are driven by two major considerations-HTS transformers must be economically competitive with conventional units, and the conductor must be robust enough to be used in a commercial manufacturing environment. The transformer design and manufacturing process will be described in order to highlight the various requirements that it imposes on the HTS conductor. Spreadsheet estimates of HTS transformer costs allow estimates of the conductor cost required for an HTS transformer to be competitive with a similarly performing conventional unit.

Pleva, E. F. [Waukesha Electric Systems, Waukesha, WI; Mehrotra, V. [Waukesha Electric Systems, Waukesha, WI; Schwenterly, S W [ORNL

2010-01-01

100

Experimental Study on the Electrical Breakdown Characteristics of Sub-Cooled Liquid Nitrogen for Designing a High Voltage Superconducting Machine  

Microsoft Academic Search

The electrical breakdown characteristics of liquid nitrogen should be investigated for developing of a high voltage superconducting machine. This paper deals with the experimental study for the verification of dielectric characteristics of sub-cooled in accordance with utilization factors. AC dielectric experiments were carried out by using sphere-plane electrode systems. The utilization factors of simulated electrode systems were controlled by gap

Jin Bae Na; Hyoungku Kang; Young Jin Hwang; Seong Eun Yang; Dong Keun Park; Duck Kweon Bae; Tae Kuk Ko

2010-01-01

101

Passive Two-Phase Cooling of Automotive Power Electronics: Preprint  

SciTech Connect

Experiments were conducted to evaluate the use of a passive two-phase cooling strategy as a means of cooling automotive power electronics. The proposed cooling approach utilizes an indirect cooling configuration to alleviate some reliability concerns and to allow the use of conventional power modules. An inverter-scale proof-of-concept cooling system was fabricated, and tests were conducted using the refrigerants hydrofluoroolefin HFO-1234yf and hydrofluorocarbon HFC-245fa. Results demonstrated that the system can dissipate at least 3.5 kW of heat with 250 cm3 of HFC-245fa. An advanced evaporator design that incorporates features to improve performance and reduce size was conceived. Simulation results indicate its thermal resistance can be 37% to 48% lower than automotive dual side cooled power modules. Tests were also conducted to measure the thermal performance of two air-cooled condensers--plain and rifled finned tube designs. The results combined with some analysis were then used to estimate the required condenser size per operating conditions and maximum allowable system (i.e., vapor and liquid) temperatures.

Moreno, G.; Jeffers, J. R.; Narumanchi, S.; Bennion, K.

2014-08-01

102

Superconductivity  

SciTech Connect

This book explains the theoretical background of superconductivity. Includes discussion of electricity, material fabrication, maglev trains, the superconducting supercollider, and Japanese-US competition. The authors reports the latest discoveries.

Langone, J.

1989-01-01

103

14 CFR 23.1045 - Cooling test procedures for turbine engine powered airplanes.  

Code of Federal Regulations, 2013 CFR

... 1 2013-01-01 2013-01-01 false Cooling test procedures for turbine engine powered airplanes...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045 Cooling test procedures for turbine engine powered...

2013-01-01

104

14 CFR 23.1045 - Cooling test procedures for turbine engine powered airplanes.  

Code of Federal Regulations, 2012 CFR

... 1 2012-01-01 2012-01-01 false Cooling test procedures for turbine engine powered airplanes...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045 Cooling test procedures for turbine engine powered...

2012-01-01

105

14 CFR 23.1045 - Cooling test procedures for turbine engine powered airplanes.  

Code of Federal Regulations, 2011 CFR

... 1 2011-01-01 2011-01-01 false Cooling test procedures for turbine engine powered airplanes...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045 Cooling test procedures for turbine engine powered...

2011-01-01

106

14 CFR 23.1045 - Cooling test procedures for turbine engine powered airplanes.  

Code of Federal Regulations, 2014 CFR

... 1 2014-01-01 2014-01-01 false Cooling test procedures for turbine engine powered airplanes...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045 Cooling test procedures for turbine engine powered...

2014-01-01

107

14 CFR 23.1045 - Cooling test procedures for turbine engine powered airplanes.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Cooling test procedures for turbine engine powered airplanes. 23.1045 Section 23.1045...Powerplant Cooling § 23.1045 Cooling test procedures for turbine engine powered airplanes. (a) Compliance...

2010-01-01

108

Dependence of the residual surface resistance of superconducting radio frequency cavities on the cooling dynamics around T{sub c}  

SciTech Connect

We report a strong effect of the cooling dynamics through T{sub c} on the amount of trapped external magnetic flux in superconducting niobium cavities. The effect is similar for fine grain and single crystal niobium and all surface treatments including electropolishing with and without 120?°C baking and nitrogen doping. Direct magnetic field measurements on the cavity walls show that the effect stems from changes in the flux trapping efficiency: slow cooling leads to almost complete flux trapping and higher residual resistance, while fast cooling leads to the much more efficient flux expulsion and lower residual resistance.

Romanenko, A., E-mail: aroman@fnal.gov; Grassellino, A., E-mail: annag@fnal.gov; Melnychuk, O.; Sergatskov, D. A. [Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)

2014-05-14

109

Evacuation time of cryogenic pipes for superconducting power transmission  

NASA Astrophysics Data System (ADS)

The vacuum insulation has been used for the thermal insulation of cryogenic pipes for the superconducting power transmission to reduce the heat leak from the environment at the room temperature to the low temperature parts. Since the cryogenic pipes, in particular, those for long distance power transmission, are considered to be thin long pipes, it might take a long time for evacuation. To estimate the evacuation time of the long cryogenic pipes, model calculations have been performed. According to the calculations, it is found that there is an optimum condition between the pumping speed, the diameter of the outer pipe and the length of the cryogenic pipe for efficient evacuation. It is also found that, if the outgassing is suppressed enough, the evacuation can be possible within 1 week even for the long cryogenic pipe with the length of 10 km. The reduction of outgassing is particularly important for the efficient evacuation.

Watanabe, Hirofumi; Sun, Jian; Yamamoto, Norimasa; Hamabe, Makoto; Kawahara, Toshio; Yamaguchi, Satarou

2013-11-01

110

Air Cooling for High Temperature Power Electronics (Presentation)  

SciTech Connect

Current emphasis on developing high-temperature power electronics, including wide-bandgap materials such as silicon carbide and gallium nitride, increases the opportunity for a completely air-cooled inverter at higher powers. This removes the liquid cooling system for the inverter, saving weight and volume on the liquid-to-air heat exchanger, coolant lines, pumps, and coolant, replacing them with just a fan and air supply ducting. We investigate the potential for an air-cooled heat exchanger from a component and systems-level approach to meet specific power and power density targets. A proposed baseline air-cooled heat exchanger design that does not meet those targets was optimized using a parametric computational fluid dynamics analysis, examining the effects of heat exchanger geometry and device location, fixing the device heat dissipation and maximum junction temperature. The CFD results were extrapolated to a full inverter, including casing, capacitor, bus bar, gate driver, and control board component weights and volumes. Surrogate ducting was tested to understand the pressure drop and subsequent system parasitic load. Geometries that met targets with acceptable loads on the system were down-selected for experimentation. Nine baseline configuration modules dissipated the target heat dissipation, but fell below specific power and power density targets. Six optimized configuration modules dissipated the target heat load, exceeding the specific power and power density targets. By maintaining the same 175 degrees C maximum junction temperature, an optimized heat exchanger design and higher device heat fluxes allowed a reduction in the number of modules required, increasing specific power and power density while still maintaining the inverter power.

Waye, S.; Musselman, M.; King, C.

2014-09-01

111

Thermally matched fluid cooled power converter  

DOEpatents

A 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. Power electronic circuits are thermally matched, such as between component layers and between the circuits and the support. The support may form 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.

Radosevich, Lawrence D.; Kannenberg, Daniel G.; Kaishian, Steven C.; Beihoff, Bruce C.

2005-06-21

112

Concurrent Wind Cooling in Power Transmission Lines  

SciTech Connect

Idaho National Laboratory and the Idaho Power Company, with collaboration from Idaho State University, have been working on a project to monitor wind and other environmental data parameters along certain electrical transmission corridors. The combination of both real-time historical weather and environmental data is being used to model, validate, and recommend possibilities for dynamic operations of the transmission lines for power and energy carrying capacity. The planned results can also be used to influence decisions about proposed design criteria for or upgrades to certain sections of the transmission lines.

Jake P Gentle

2012-08-01

113

Modular power converter having fluid cooled support  

DOEpatents

A 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, in conjunction with other packaging features may form 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.; Radosevich, Lawrence D.; Meyer, Andreas A.; Gollhardt, Neil; Kannenberg, Daniel G.

2005-12-06

114

Modular power converter having fluid cooled support  

DOEpatents

A 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, in conjunction with other packaging features may form 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.; Radosevich, Lawrence D.; Meyer, Andreas A.; Gollhardt, Neil; Kannenberg, Daniel G.

2005-09-06

115

High temperature superconductivity technology for advanced space power systems  

NASA Technical Reports Server (NTRS)

In 1987, the Lewis Research center of the NASA and the Argonne National Laboratory of the Department of Energy joined in a cooperative program to identify and assess high payoff space and aeronautical applications of high temperature superconductivity (HTSC). The initial emphasis of this effort was limited, and those space power related applications which were considered included microwave power transmission and magnetic energy storage. The results of these initial studies were encouraging and indicated the need of further studies. A continuing collaborative program with Argonne National Laboratory has been formulated and the Lewis Research Center is presently structuring a program to further evaluate HTSC, identify applications and define the requisite technology development programs for space power systems. This paper discusses some preliminary results of the previous evaluations in the area of space power applications of HTSC which were carried out under the joint NASA-DOE program, the future NASA-Lewis proposed program, its thrusts, and its intended outputs and give general insights on the anticipated impact of HTSC for space power applications of the future.

Faymon, Karl A.; Myers, Ira T.; Connolly, Denis J.

1990-01-01

116

Design and optimization of geothermal power generation, heating, and cooling  

NASA Astrophysics Data System (ADS)

Most of the world's geothermal power plants have been built in 1970s and 1980s following 1973 oil crisis. Urgency to generate electricity from alternative energy sources and the fact that geothermal energy was essentially free adversely affected careful designs of plants which would maximize their performance for a given geothermal resource. There are, however, tremendous potentials to improve performance of many existing geothermal power plants by retrofitting, optimizing the operating conditions, re-selecting the most appropriate binary fluid in binary plants, and considering cogeneration such as a district heating and/or cooling system or a system to preheat water entering boilers in industrial facilities. In this dissertation, some representative geothermal resources and existing geothermal power plants in Nevada are investigated to show these potentials. Economic analysis of a typical geothermal resource shows that geothermal heating and cooling may generate up to 3 times as much revenue as power generation alone. A district heating/cooling system is designed for its incorporation into an existing 27 MW air-cooled binary geothermal power plant. The system as designed has the capability to meet the entire heating needs of an industrial park as well as 40% of its cooling needs, generating potential revenues of $14,040,000 per year. A study of the power plant shows that evaporative cooling can increase the power output by up to 29% in summer by decreasing the condenser temperature. The power output of the plant can be increased by 2.8 percent by optimizing the maximum pressure in the cycle. Also, replacing the existing working fluid isobutane by butane, R-114, isopentane, and pentane can increase the power output by up to 2.5 percent. Investigation of some well-known geothermal power generation technologies as alternatives to an existing 12.8 MW single-flash geothermal power plant shows that double-flash, binary, and combined flash/binary designs can increase the net power output by up to 31 percent, 35 percent, and 54 percent, respectively, at optimum operating conditions. An economic comparison of these designs appears to favor the combined flash/binary design, followed by the double-flash design.

Kanoglu, Mehmet

117

Convection of Paramagnetic Fluid in a Cube Heated and Cooled from Side Walls and Placed below a Superconducting Magnet  

NASA Astrophysics Data System (ADS)

The magnetic convection of paramagnetic fluid is studied in a strong magnetic field. The fluid in a cubic enclosure is heated from one vertical wall and cooled from the opposite one. The fluid is the 80% mass aqueous solution of glycerol with 0.8 mol/kg concentration of gadolinium nitrate hexahydrate to make the working fluid paramagnetic. The small amount of liquid crystal slurry is added to the fluid in order to visualize the temperature profiles in a vertical cross-section. This system is placed directly below the solenoid of the superconducting magnet which is oriented vertically. The temperature of cold wall is constantly controlled by the water flowing from a thermostating bath. On the other hand, the hot wall is heated by a nichrome wire from a DC power supply. In the numerical computations, the configuration of the system is modeled to be as close as possible to the real system. The physical properties of the working fluid are used to compute dimensionless parameters in the numerical model and the computations are carried out for corresponding cases. Later, the numerical and experimental results are compared with each other.

Bednarz, Tomasz; Fornalik, Elzbieta; Tagawa, Toshio; Ozoe, Hiroyuki; Szmyd, Janusz S.

118

LN 2 circulation in cryopipes of superconducting power transmission line  

NASA Astrophysics Data System (ADS)

We propose and consider the application of superconducting power transmission lines (SC PTs) using high temperature superconductors (HTSs) for further reduction of the electricity losses. To keep HTS cable at low temperature it is usual to use liquid nitrogen (LN 2). Straight and bellows pipes used in SC PT have different hydraulic friction factors due to differences in the shape of the wall surfaces. Moreover, the decentering of the HTS cable, which is unfixed at the center of the pipeline, also influences the LN 2 flow. In the case of long SC PTs, high power must be expended to overcome hydraulic friction. There are two methods to evaluate pressure losses. One is based on empirical formulae and another is based on the algorithms of computational fluid dynamics (CFD). Empirical formulae can estimate pressure losses for long pipes, but the decentering of the cable is not considered. CFD computations describe flow behavior taking into account cable position inside the pipeline, though there is a limit to computable length due to the dependence on the number of mesh points and computation capacity. In this paper, circulation losses and pump power are estimated in straight and bellows pipes forming circulation channels by both methods. For a 40 mm diameter cable in an 80 mm diameter pipe, with the bellows pipe segments covering 2% of the length, and a heat loss of 1 W/m, the required flow rate and pump power for a circulation of 10 km are approximately 19 L/min and 10 W, respectively.

Sasaki, A.; Ivanov, Yu.; Yamaguchi, S.

2011-09-01

119

Keeping Cool With Solar-Powered Refrigeration  

NASA Technical Reports Server (NTRS)

In the midst of developing battery-free, solar-powered refrigeration and air conditioning systems for habitats in space, David Bergeron, the team leader for NASA's Advanced Refrigerator Technology Team at Johnson Space Center, acknowledged the need for a comparable solar refrigerator that could operate in conjunction with the simple lighting systems already in place on Earth. Bergeron, a 20-year veteran in the aerospace industry, founded the company Solus Refrigeration, Inc., in 1999 to take the patented advanced refrigeration technology he co-developed with his teammate, Johnson engineer Michael Ewert, to commercial markets. Now known as SunDanzer Refrigeration, Inc., Bergeron's company is producing battery-free, photovoltaic (PV) refrigeration systems under license to NASA, and selling them globally.

2003-01-01

120

Design of RF power coupler for superconducting cavities  

NASA Astrophysics Data System (ADS)

A new power coupler has been designed and is being prototyped by Argonne National Laboratory (ANL) for use with any of the ANL proposed superconducting (SC) half- or quarter-wave cavities for SARAF [1] and Project-X [2]. The 50 Ohm coaxial capacitive coupler is required to operate in the CW regime with up to 15 kW of forward power and under any condition for the reflected power. A key feature is a moveable copper plated stainless steel bellows which will permit up to 3 cm of axial stroke and adjustment of the external quality factor by roughly one order of magnitude in the range of 105 to 106. The mechanical and vacuum design includes two ceramic windows, one operating at room temperature and another at 70 Kelvin. The two window design allows the portion of the coupler assembled onto the SC cavity in the clean room to be compact and readily cleanable. Other design features include thermal intercepts to provide a large margin for RF heating and a mechanical guide assembly to operate cold and under vacuum with high reliability.

Kutsaev, S. V.; Kelly, M. P.; Ostroumov, P. N.

2012-11-01

121

Winding, cooling and initial testing of a 10 H superconducting MgB2 coil for an induction heater  

Microsoft Academic Search

A 10 H superconducting MgB2 coil, suitable for an induction heating application, has been wound, cooled and initially tested. Eight kilometres of MgB2 tape were first insulated and then wound into double pancake coils before being assembled into the complete coil. The process is described in detail, focusing on hands-on experience gained, especially regarding the different steps in the wet-winding

F. Sætre; I. Hiltunen; M. Runde; N. Magnusson; J. Järvelä; J. Bjerkli; E. Engebrethsen

2011-01-01

122

Characteristic Analysis of DC Electric Railway Systems with Superconducting Power Cables Connecting Power Substations  

NASA Astrophysics Data System (ADS)

The application of superconducting power cables to DC electric railway systems has been studied. It could leads to an effective use of regenerative brake, improved energy efficiency, effective load sharing among the substations, etc. In this study, an electric circuit model of a DC feeding system is built and numerical simulation is carried out using MATLAB-Simulink software. A modified electric circuit model with an AC power grid connection taken into account is also created to simulate the influence of the grid connection. The analyses have proved that a certain amount of energy can be conserved by introducing superconducting cables, and that electric load distribution and concentration among the substations depend on the substation output voltage distribution.

Ohsaki, H.; Matsushita, N.; Koseki, T.; Tomita, M.

2014-05-01

123

14 CFR 23.1047 - Cooling test procedures for reciprocating engine powered airplanes.  

Code of Federal Regulations, 2012 CFR

... 1 2012-01-01 2012-01-01 false Cooling test procedures for reciprocating engine powered...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047 Cooling test procedures for reciprocating engine...

2012-01-01

124

14 CFR 23.1047 - Cooling test procedures for reciprocating engine powered airplanes.  

Code of Federal Regulations, 2010 CFR

... 1 2010-01-01 2010-01-01 false Cooling test procedures for reciprocating engine powered...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047 Cooling test procedures for reciprocating engine...

2010-01-01

125

14 CFR 23.1047 - Cooling test procedures for reciprocating engine powered airplanes.  

Code of Federal Regulations, 2014 CFR

... 1 2014-01-01 2014-01-01 false Cooling test procedures for reciprocating engine powered...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047 Cooling test procedures for reciprocating engine...

2014-01-01

126

14 CFR 23.1047 - Cooling test procedures for reciprocating engine powered airplanes.  

Code of Federal Regulations, 2013 CFR

... 1 2013-01-01 2013-01-01 false Cooling test procedures for reciprocating engine powered...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047 Cooling test procedures for reciprocating engine...

2013-01-01

127

14 CFR 23.1047 - Cooling test procedures for reciprocating engine powered airplanes.  

Code of Federal Regulations, 2011 CFR

... 1 2011-01-01 2011-01-01 false Cooling test procedures for reciprocating engine powered...AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047 Cooling test procedures for reciprocating engine...

2011-01-01

128

Specific power of liquid-metal-cooled reactors  

SciTech Connect

Calculations of the core specific power for conceptual space-based liquid-metal-cooled reactors, based on heat transfer considerations, are presented for three different fuel types: (1) pin-type fuel; (2) cermet fuel; and (3) thermionic fuel. The calculations are based on simple models and are intended to provide preliminary comparative results. The specific power is of interest because it is a measure of the core mass required to produce a given amount of power. Potential problems concerning zero-g critical heat flux and loss-of-coolant accidents are also discussed because these concerns may limit the core specific power. Insufficient experimental data exists to accurately determine the critical heat flux of liquid-metal-cooled reactors in space; however, preliminary calculations indicate that it may be a concern. Results also indicate that the specific power of the pin-type fuels can be increased significantly if the gap between the fuel and the clad is eliminated. Cermet reactors offer the highest specific power because of the excellent thermal conductivity of the core matrix material. However, it may not be possible to take fuel advantage of this characteristic when loss-of-coolant accidents are considered in the final core design. The specific power of the thermionic fuels is dependent mainly on the emitter temperature. The small diameter thermionic fuels have specific powers comparable to those of pin-type fuels. 11 refs., 12 figs, 2 tabs.

Dobranich, D.

1987-10-01

129

Two-Phase Cooling Method Using R134a Refrigerant to Cool Power Electronic Devices  

SciTech Connect

This paper presents a two-phase cooling method using R134a refrigerant to dissipate the heat energy (loss) generated by power electronics (PE) such as those associated with rectifiers, converters, and inverters for a specific application in hybrid-electric vehicles (HEVs). The cooling method involves submerging PE devices in an R134a bath, which limits the junction temperature of PE devices while conserving weight and volume of the heat sink without sacrificing equipment reliability. First, experimental tests that included an extended soak for more than 300 days were performed on a submerged IGBT and gate-controller card to study dielectric characteristics, deterioration effects, and heat flux capability of R134a. Results from these tests illustrate that R134a has high dielectric characteristics, no deterioration on electrical components, and a heat flux of 114 W/cm 2 for the experimental configuration. Second, experimental tests that included simultaneous operation with a mock automotive air-conditioner (A/C) system were performed on the same IGBT and gate controller card. Data extrapolation from these tests determined that a typical automotive A/C system has more than sufficient cooling capacity to cool a typical 30 kW traction inverter. Last, a discussion and simulation of active cooling of the IGBT junction layer with R134a refrigerant is given. This technique will drastically increase the forward current ratings and reliability of the PE device

Lowe, Kirk T [ORNL; Tolbert, Leon M [ORNL; Ayers, Curtis William [ORNL; Ozpineci, Burak [ORNL; Campbell, Jeremy B [ORNL

2007-01-01

130

Hybrid Cooling for Geothermal Power Plants: Final ARRA Project Report  

SciTech Connect

Many binary-cycle geothermal plants use air as the heat rejection medium. Usually this is accomplished by using an air-cooled condenser (ACC) system to condense the vapor of the working fluid in the cycle. Many air-cooled plants suffer a loss of production capacity of up to 50% during times of high ambient temperatures. Use of limited amounts of water to supplement the performance of ACCs is investigated. Deluge cooling is found to be one of the least-cost options. Limiting the use of water in such an application to less than one thousand operating hours per year can boost plant output during critical high-demand periods while minimizing water use in binary-cycle geothermal power plants.

Bharathan, D.

2013-06-01

131

Mathematical modeling of passive dry cooling for power plants in arid land  

Microsoft Academic Search

Radiative cooling from surfaces gives a promising alternative to conventional cooling techniques. A new means for cooling power plants through passive dry cooling is explored utilizing convection and infrared radiation from a covered cooling pond, such that evaporation is suppressed. A mathematical model is established to predict the temperature distribution along the proposed prototype pond. A quantitative study of the

I. A. Olwi; J. A. Sabbagh; A. M. A. Khalifa

1992-01-01

132

Application of superconducting magnet energy storage to improve power system dynamic performance  

Microsoft Academic Search

The application of superconducting magnet energy storage (SMES) to the stabilization of a power system with long-distance bulk power transmission lines which has the problem of poorly damped power oscillations is presented. Control schemes for stabilization using SMES capable of controlling active and reactive power simultaneously in four quadrant ranges are proposed. The effective locations and the necessary capacities of

Y. Mitani; K. Tsuji; Y. Murakami

1988-01-01

133

Four quadrant magnet power supply for superconducting and conventional accelerator applications  

Microsoft Academic Search

Modern conventional and superconducting accelerators often require bipolar power supplies capable of operating with high precision from zero to full output. An SCR type power supply comprised of two SCR bridges and operating with circulating current does an excellent job of satisfying this difficult requirement. Power supplies of this type are often called four-quadrant or dual converter power supplies with

Raymond J. Yarema

1981-01-01

134

Superconductivity  

SciTech Connect

The author presents treatment of the field of superconductivity, from its inception in 1911 to the present day. Its discussions range from scientific aspects to applications in business, medicine, etc. This book provides definitions and a selective bibliography.

Mayo, J.L.

1988-01-01

135

Cooling options for high-average-power laser mirrors  

NASA Astrophysics Data System (ADS)

Thermally-induced deformations of steering mirrors reflecting 100 J/10 Hz laser pulses in vacuum have been analyzed. This deformation is caused by the thermal stress arisen due to parasitic absorption of 1 kW square-shaped flat-top laser beam in the dielectric multi-layer structure. Deformation depends on amount of absorbed power and geometry of the mirror as well as on the heat removal scheme. In our calculations, the following percentages of absorption of the incident power have been used: 1%, 0.5% and 0.1%. The absorbed power has been considered to be much higher than that expected in reality to assess the worst case scenario. Rectangular and circular mirrors made of zerodur (low thermal expansion glass) were considered for these simulations. The effect of coating layers on induced deformations has been neglected. Induced deformation of the mirror surface can significantly degrade the quality of the laser beam in the beam delivery system. Therefore, the proper design of the cooling scheme for the mirror in order to minimize the deformations is needed. Three possible cooling schemes of the mirror have been investigated. The first one takes advantage of a radiation cooling of the mirror and a copper heatsink fixed to the rear face of the mirror, the second scheme is based on additional heat conduction provided by flexible copper wires connected to the mirror holder, and the last scheme combines two above mentioned methods.

Vojna, D.; Slezak, O.; Lucianetti, A.; Mocek, T.

2015-01-01

136

Electromagnetic simulations and properties of the fundamental power couplers for the SNS superconducting cavities  

Microsoft Academic Search

The Spallation Neutron Source (SNS) makes use of superconducting cavities for the acceleration of negative H ions in the main linac. Two types of 6-cell Niobium cavities are used in the superconducting portion of the linac: 33 ?=0.61 cavities and 48 ?=0.81 cavities. Each cavity is powered via a coaxial fundamental power coupler (FPC) of a simple yet robust design.

Y. Kangt; S. Kim; M. Doleans; I. E. Campisi; M. Stirbet; P. Kneisel; G. Ciovati; G. Wu; P. Yla-Oijala

2001-01-01

137

Development of passive dry cooling system for power plants in arid land  

Microsoft Academic Search

Availability of large amounts of cooling water is essential for steam power plants. In inland arid areas, gas turbines are usually used for electric power generation at low efficiency and high operation costs. Dry cooling towers are another option but they are not effective with high ambient temperature. This work explores the use of radiative cooling for power plants and

J. A. Sabbagh; A. M. A. Khalifa; I. A. Olwi

1993-01-01

138

Efficient transfer of positrons from a buffer-gas-cooled accumulator into an orthogonally oriented superconducting solenoid for antihydrogen studies  

NASA Astrophysics Data System (ADS)

Positrons accumulated in a room-temperature buffer-gas-cooled positron accumulator are efficiently transferred into a superconducting solenoid which houses the ATRAP cryogenic Penning trap used in antihydrogen research. The positrons are guided along a 9 m long magnetic guide that connects the central field lines of the 0.15 T field in the positron accumulator to the central magnetic field lines of the superconducting solenoid. Seventy independently controllable electromagnets are required to overcome the fringing field of the large-bore superconducting solenoid. The guide includes both a 15° upward bend and a 105° downward bend to account for the orthogonal orientation of the positron accumulator with respect to the cryogenic Penning trap. Low-energy positrons ejected from the accumulator follow the magnetic field lines within the guide and are transferred into the superconducting solenoid with nearly 100% efficiency. A 7 m long 5 cm diameter stainless-steel tube and a 20 mm long, 1.5 mm diameter cryogenic pumping restriction ensure that the 10-2 mbar pressure in the accumulator is isolated well from the extreme vacuum required in the Penning trap to allow for long antimatter storage times.

Comeau, D.; Dror, A.; Fitzakerley, D. W.; George, M. C.; Hessels, E. A.; Storry, C. H.; Weel, M.; Grzonka, D.; Oelert, W.; Gabrielse, G.; Kalra, R.; Kolthammer, W. S.; McConnell, R.; Richerme, P.; Müllers, A.; Walz, J.; ATRAP Collaboration

2012-04-01

139

Ice Thermal Storage Systems for Nuclear Power Plant Supplemental Cooling and Peak Power Shifting  

SciTech Connect

Availability of cooling water has been one of the major issues for the nuclear power plant site selection. Cooling water issues have frequently disrupted the normal operation at some nuclear power plants during heat waves and long draught. One potential solution is to use ice thermal storage (ITS) systems that reduce cooling water requirements and boost the plant’s thermal efficiency in hot hours. ITS uses cheap off-peak electricity to make ice and uses the ice for supplemental cooling during peak demand time. ITS also provides a way to shift a large amount of electricity from off peak time to peak time. For once-through cooling plants near a limited water body, adding ITS can bring significant economic benefits and avoid forced derating and shutdown during extremely hot weather. For the new plants using dry cooling towers, adding the ITS systems can effectively reduce the efficiency loss during hot weather so that new plants could be considered in regions lack of cooling water. This paper will review light water reactor cooling issues and present the feasibility study results.

Haihua Zhao; Hongbin Zhang; Phil Sharpe; Blaise Hamanaka; Wei Yan; WoonSeong Jeong

2013-03-01

140

A Gas-Cooled Reactor Surface Power System  

SciTech Connect

A human outpost on Mars requires plentiful power to assure survival of the astronauts. Anywhere from 50 to 500 kW of electric power (kWe) will be needed, depending on the number of astronauts, level of scientific activity, and life- cycle closure desired. This paper describes a 250-kWe power system based on a gas-cooled nuclear reactor with a recuperated closed Brayton cycle conversion system. The design draws upon the extensive data and engineering experience developed under the various high-temperature gas cooled reactor programs and under the SP-100 program. The reactor core is similar in power and size to the research reactors found on numerous university campuses. The fuel is uranium nitide clad in Nb 1 %Zr, which has been extensively tested under the SP-I 00 program The fiel rods are arranged in a hexagonal array within a BeO block. The BeO softens the spectrum, allowing better use of the fbel and stabilizing the geometty against deformation during impact or other loadings. The system has a negative temperature feedback coefficient so that the power level will automatically follow a variable load without the need for continuous adjustment of control elements. Waste heat is removed by an air-cooled heat exchanger using cold Martian air. The amount of radioactivity in the reactor at launch is very small (less than a Curie, and about equal to a truckload of uranium ore). The system will need to be engineered so that criticality cannot occur for any launch accident. This system is also adaptable for electric propulsion or life-support during transit to and from Mars.

Harms, G.A.; Lenard, R.X.; Lipinski, R.J.; Wright, S.A.

1998-11-09

141

Design and comparative analysis of 10 MW class superconducting wind power generators according to different types of superconducting wires  

NASA Astrophysics Data System (ADS)

Wind turbine concepts can be classified into the geared type and the gearless type. The gearless type wind turbine is more attractive due to advantages of simplified drive train and increased energy yield, and higher reliability because the gearbox is omitted. In addition, this type resolves the weight issue of the wind turbine with the light weight of gearbox. However, because of the low speed operation, this type has disadvantage such as the large diameter and heavy weight of generator. Super-Conducting (SC) wind power generator can reduce the weight and volume of a wind power system. Properties of superconducting wire are very different from each company. This paper considers the design and comparative analysis of 10 MW class SC wind power generators according to different types of SC wires. Super-Conducting Synchronous Generators (SCSGs) using YBCO and Bi-2223 wires are optimized by an optimal method. The magnetic characteristics of the SCSGs are investigated using the finite elements method program. The optimized specifications of the SCSGs are discussed in detail, and the optimization processes can be used effectively to develop large scale wind power generation systems.

Sung, Hae-Jin; Kim, Gyeong-Hun; Kim, Kwangmin; Park, Minwon; Yu, In-Keun; Kim, Jong-Yul

2013-11-01

142

Improved thermal isolation for superconducting magnet systems  

NASA Technical Reports Server (NTRS)

Closed-cycle refrigerating system for superconductive magnet and maser is operated in vacuum environment. Each wire leading from external power source passes through cooling station which blocks heat conduction. In connection with these stations, switch with small incandescent light bulb, which generates heat, is used to stop superconduction.

Wiebe, E. R.

1974-01-01

143

Power Flow Stabilization and Control of Microgrid with Wind Generation by Superconducting Magnetic Energy Storage  

Microsoft Academic Search

High penetration of renewable energy sources such as wind generation in microgrids (MGs) causes fluctuations of power flow and significantly affects the power system (PS) operation. This can lead to severe problems, such as system frequency oscillations, and\\/or violations of power lines capability. With the proper control, superconducting magnetic energy storage (SMES) is able to signifi- cantly enhance the dynamic

Marcelo Gustavo Molina; Pedro Enrique Mercado

2011-01-01

144

Superconductivity  

SciTech Connect

Superconducting materials can conduct dc electricity-sometimes in enormous currents-with to resistance. They can cause a locomotive to levitate. They have been tested in noteworthy projects. But they must still overcome several economic as well as technical constraints. This article discusses some of these obstacles.

Rosen, J.

1988-06-01

145

Superconductivity:  

NASA Astrophysics Data System (ADS)

In this paper a short historical account of the discovery of superconductivity and of its gradual development is given. The physical interpretation of its various aspects took about forty years (from 1911 to 1957) to reach a successful description of this phenomenon in terms of a microscopic theory At the very end it seemed that more or less everything could be reasonably interpreted even if modifications and refinements of the original theory were necessary. In 1986 the situation changed abruptly when a cautious but revolutionary paper appeared showing that superconductivity was found in certain ceramic oxides at temperatures above those up to then known. A rush of frantic experimental activity started world-wide and in less than one year it was shown that superconductivity is a much more widespread phenomenon than deemed before and can be found at temperatures well above the liquid air boiling point. The complexity and the number of the substances (mainly ceramic oxides) involved call for a sort of modern alchemy if compounds with the best superconducting properties are to be manufactured. We don't use the word alchemy in a deprecatory sense but just to emphasise that till now nobody can say why these compounds are what they are: superconductors.

Sacchetti, N.

146

Ensure Continuous Power to Critical Industrial Processes with the New Superconducting Storage Device (SSD™)  

E-print Network

ENSURE CONTINUOUS POWER TO CRITICAL INDUSTRIAL PROCESSES WITH THE NEW SUPER CONDUCTING STORAGE DEVICE (SSD?) DR. CAREL C. DEWINKEL, MANAGER OF APPLICATIONS ENGINEERING & MR. PAUL F. KOEPPE, PRESIDENT SUPERCONDUCTIVITY, INC., MADISON, WISCONSIN... controlled equipment which is especially vulnerable to these momentary voltage disturbances. These short-term disturbances are costing U.S. industry millions of dollars a year in downtime, product loss and equipment damage. The Superconducting Storage...

Dewinkel, C. C.; Koeppe, P. F.

147

Commissioning Tests of the Bonneville Power Administration 30 MJ Superconducting Magnetic Energy Storage Unit  

Microsoft Academic Search

A 30 MJ (8.4 kWh) Superconducting Magnetic Energy Storage (SMES) unit with a 10 MW converter has been installed and commissioned at the Bonneville Power Administration (BPA) substation in Tacoma, Washington. This is the first large-scale application in the US of superconductivity in an electric utility system. The unit, which is capable of absorbing and releasing up to 10 MJ

H. J. Boenig; J. F. Hauer

1985-01-01

148

FORAGE FISH POPULATIONS AND GROWTH OF MUSKELLUNGE IN A SOUTH DAKOTA POWER PLANT COOLING RESERVOIR  

E-print Network

(Lepomis macrochirus) in Big Stone Power Plant cooling reservoir, South Dakota, and other power plant) of bluegills (Lepomis macrochirus), Big Stone Power Plant cooling reservoir, South Dakota, 1979. · · · · · · · · · . · · · · · 18 8. Back-calculated growth increments (mm) of bluegills (Lepomis macrochirus), Big Stone Power

149

First high power pulsed tests of a dressed 325 MHz superconducting single spoke resonator at Fermilab  

SciTech Connect

In the recently commissioned superconducting RF cavity test facility at Fermilab (SCTF), a 325 MHz, {beta} = 0.22 superconducting single-spoke resonator (SSR1) has been tested for the first time with its input power coupler. Previously, this cavity had been tested CW with a low power, high Q{sub ext} test coupler; first as a bare cavity in the Fermilab Vertical Test Stand and then fully dressed in the SCTF. For the tests described here, the design input coupler with Q{sub ext} {approx} 10{sup 6} was used. Pulsed power was provided by a Toshiba E3740A 2.5 MW klystron.

Madrak, R.; Branlard, J.; Chase, B.; Darve, C.; Joireman, P.; Khabiboulline, T.; Mukherjee, A.; Nicol, T.; Peoples-Evans, E.; Peterson, D.; Pischalnikov, Y.; /Fermilab

2011-03-01

150

IMPROVEMENT OF THE PERFORMANCE OF A SUPERCONDUCTING TURBOGENERATOR THROUGH USE OF A CONTROLLABLE REACTIVE POWER COMPENSATOR  

Microsoft Academic Search

This paper presents the dynamic performance of a superconducting turbo-generator which employes a thyristor controlled static reactive power compensator at its terminals. The application of the fast acting compensator external to the machine, in a power system, is foreseen as one possible alternative to alleviate the excitation problems which arise on account of the extremely large field time constant of

P. K. DASH; R. M. MATHUR; A. E. HAMMAD

1977-01-01

151

DIII-D water-cooling system upgrades through modeling and power saving projects  

Microsoft Academic Search

The DIII-D water-cooling system for the fusion facility at General Atomics consists of the vessel and coil cooling water systems (DIII-D water), components cooling water systems (power supplies, ion-sources, diagnostics and gyrotrons), and heat rejection system (cooling tower and heat exchanger) for the operation of the fusion facility. Since 2005 the water-cooling systems have undergone major upgrades, resulting in average

H. H. Yip; P. S. Mauzey; P. M. Anderson; T. Le; T. Hegstad; A. Thomas; D. Leung

2009-01-01

152

Non-Cooled Power System for Venus Lander  

NASA Technical Reports Server (NTRS)

The Planetary Science Decadal Survey of 2013-2022 stated that the exploration of Venus is of significant interest. Studying the seismic activity of the planet is of particular importance because the findings can be compared to the seismic activity of Earth. Further, the geological and atmospheric properties of Venus will shed light into the past and future of Earth. This paper presents a radioisotope power system (RPS) design for a small low-power Venus lander. The feasibility of the new power system is then compared to that of primary batteries. A requirement for the power source system is to avoid moving parts in order to not interfere with the primary objective of the mission - to collect data about the seismic activity of Venus using a seismometer. The target mission duration of the lander is 117 days, a significant leap from Venera 13, the longest-lived lander on the surface of Venus, which survived for 2 hours. One major assumption for this mission design is that the power source system will not provide cooling to the other components of the lander. This assumption is based on high-temperature electronics technology that will enable the electronics and components of the lander to operate at Venus surface temperature. For the proposed RPS, a customized General Purpose Heat Source Radioisotope Thermoelectric Generator (GPHSRTG) is designed and analyzed. The GPHS-RTG is chosen primarily because it has no moving parts and it is capable of operating for long duration missions on the order of years. This power system is modeled as a spherical structure for a fundamental thermal analysis. The total mass and electrical output of the system are calculated to be 24 kilograms and 26 Watts, respectively. An alternative design for a battery-based power system uses Sodium Sulfur batteries. To deliver a similar electrical output for 117 days, the battery mass is calculated to be 234 kilograms. Reducing mission duration or power required will reduce the required battery mass. Finally, the advantages and disadvantages of both power systems with regard to science return, risk, and cost are briefly compared. The design of the radioisotope power system is considerably riskier because it is novel and would require additional years of further refinement, manufacturing, safety analysis, and testing that the primary batteries do not need. However, the lifetime of the radioisotope power system makes its science return more promising.

Salazar, Denise; Landis, Geoffrey A.; Colozza, Anthony J.

2014-01-01

153

Fiber optic cryogenic sensors for superconducting magnets and superconducting power transmission lines at CERN  

NASA Astrophysics Data System (ADS)

The design, fabrication and tests of a new generation of superconducting magnets for the upgrade of the LHC require the support of an adequate, robust and reliable sensing technology. The use of Fiber Optic Sensors is becoming particularly challenging for applications in extreme harsh environments such as ultra-low temperatures, high electromagnetic fields and strong mechanical stresses offering perspectives for the development of technological innovations in several applied disciplines.

Chiuchiolo, A.; Bajko, M.; Perez, J. C.; Bajas, H.; Consales, M.; Giordano, M.; Breglio, G.; Palmieri, L.; Cusano, A.

2014-08-01

154

Cooling system, for power generating plant, using split or partitioned heat exchanger  

SciTech Connect

Apparatus and method comprising a base cooling system using a refrigeration cycle, a peak-shaving system using a secondary cooling liquid, and a regeneration system for the peak-shaving system secondary cooling liquid. A split or partitioned heat exchanger alternately condenses only the refrigerant in the base cooling system or it condenses that refrigerant and a refrigerant used to cool hot secondary cooling liquid. The apparatus can be used in power generating plants with the split heat exchanger located in a cooling tower.

Husain, M.; Lai, B.; Schmitt, R.L.

1982-02-16

155

Solar-powered\\/fuel-assisted Rankine cycle power and cooling system - Sensitivity analysis  

Microsoft Academic Search

The subject of this analysis is a solar power\\/cooling system based on a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100 C, and it is then superheated to about 600 C in a fossil-fuel-fired superheater. The addition of about 20-26 percent of energy as fuel doubles the power cycle's efficiency

N. Lior; K. Koai

1984-01-01

156

Solar-powered\\/fuel-assisted Rankine cycle power and cooling system: sensitivity analysis  

Microsoft Academic Search

The subject of this analysis is a solar power\\/ cooling system based on a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100° C, and it is then superheated to about 600° C in a fossil-fuel fired superheater. The addition of about 20-26% of energy as fuel doubles the power cycle's

N. Lior; K. Koai

1982-01-01

157

Higher-order-mode (HOM) power in elliptical superconducting cavities for intense pulsed proton accelerators  

SciTech Connect

In linacs for intense pulsed proton accelerators, the beam has a multiple time-structure, and each beam time-structure generates resonance. When a higher-order mode (HOM) is near these resonance frequencies, the induced voltage could be large and accordingly the resulting HOM power, too. In order to understand the effects of a complex beam time-structure on the mode excitations and the resulting HOM powers in elliptical superconducting cavities, analytic expressions are developed, with which the beam-induced voltage and corresponding power are explored, taking into account the properties of HOM frequency behavior in elliptical superconducting cavities. The results and understandings from this analysis are presented with the beam parameters of the Spallation Neutron Source (SNS) superconducting linac.

Sang-ho Kim; Marc Doleans; Dong-o Jeon; Ronald Sundelin

2002-10-01

158

A coaxial HOM coupler for a superconducting RF cavity and its low-power measurement results  

NASA Astrophysics Data System (ADS)

A resonant buildup of beam-induced fields in a superconducting radio frequency (RF) cavity may make a beam unstable or a superconducting RF cavity quench. Higher-order mode (HOM) couplers are used for damping higher-order modes to avoid such a resonant buildup. A coaxial HOM coupler based on the TTF (TESLA Test Facility) HOM coupler has been designed for the superconducting RF cavities at the Proton Engineering Frontier Project (PEFP) in order to overcome notch frequency shift and feed-through tip melting issues. In order to confirm the HOM coupler design and finalize its structural dimensions, two prototype HOM couplers have been fabricated and tested. Low-power testing and measurement of the HOM couplers has shown that the HOM coupler has good filter properties and can fully meet the damping requirements of the PEFP low-beta superconducting RF linac.

Sun, An; Tang, Ya-Zhe; Zhang, Li-Ping; Li, Ying-Min; Han-Sung, Kim

2011-03-01

159

Ice Thermal Storage Systems for LWR Supplemental Cooling and Peak Power Shifting  

Microsoft Academic Search

Availability of enough cooling water has been one of the major issues for the nuclear power plant site selection. Cooling water issues have frequently disrupted the normal operation at some nuclear power plants during heat waves and long draught. The issues become more severe due to the new round of nuclear power expansion and global warming. During hot summer days,

Haihua Zhao; Hongbin Zhang; Phil Sharpe; Blaise Hamanaka; Wei Yan; WoonSeong Jeong

2010-01-01

160

Low-Cost Superconducting Wire for Wind Generators: High Performance, Low Cost Superconducting Wires and Coils for High Power Wind Generators  

SciTech Connect

REACT Project: The University of Houston will develop a low-cost, high-current superconducting wire that could be used in high-power wind generators. Superconducting wire currently transports 600 times more electric current than a similarly sized copper wire, but is significantly more expensive. The University of Houston’s innovation is based on engineering nanoscale defects in the superconducting film. This could quadruple the current relative to today’s superconducting wires, supporting the same amount of current using 25% of the material. This would make wind generators lighter, more powerful and more efficient. The design could result in a several-fold reduction in wire costs and enable their commercial viability of high-power wind generators for use in offshore applications.

None

2012-01-01

161

Preliminary Design of Poloidal Field Power Supply for HT-7U Super-Conducting Tokamak  

NASA Astrophysics Data System (ADS)

This paper presents the preliminary design of poloidal field power supply system of HT-7U super-conducting tokamak. With an emphasis on AC/DC power converter, DC circuit breaker, quench protection, harmonic suppression and static var. compensation, and AC power system, the design principle and features are introduced, the design scheme and R & D progress are described, the simulation studies and laboratory test are presented too.

Liu, Zheng-zhi; Xu, Jia-zhi; Fu, Peng; Tao, Jun; jia-liang, Wen; Huang, Qi; Li, Jun; Gao, Ge

2000-12-01

162

Princeton fusion power plant superconducting magnet system and costs  

Microsoft Academic Search

Details are given of the superconducting magnet system consisting of toroidal field, divertor, ohmic heating, equilibrium field and control field magnets, all of which are wound of NbSn conductor. The toroidal field coils are of the moment-free, D type. The toroidal field magnet is comprised of 48 discrete D coils, 12m x 19m bore. The magnet which is operated at

J. File

1975-01-01

163

A role for high frequency superconducting devices in free space power transmission systems  

NASA Technical Reports Server (NTRS)

Major advances in space power technology are being made in photovoltaic, solar thermal, and nuclear systems. Despite these advances, the power systems required by the energy and power intensive mission of the future will be massive due to the large collecting surfaces, large thermal management systems, and heavy shielding. Reducing this mass on board the space vehicle can result in significant benefits because of the high cost of transporting and moving mass about in space. An approach to this problem is beaming the power from a point where the massiveness of the power plant is not such a major concern. The viability of such an approach was already investigated. Efficient microwave power beam transmission at 2.45 GHz was demonstrated over short range. Higher frequencies are desired for efficient transmission over several hundred or thousand kilometers in space. Superconducting DC-RF conversion as well as RF-DC conversion offers exciting possibilities. Multivoltage power conditioning for multicavity high power RF tubes could be eliminated since only low voltages are required for Josephson junctions. Small, high efficiency receivers may be possible using the reverse Josephson effects. A conceptual receiving antenna design using superconducting devices to determine possible system operating efficiency is assessed. If realized, these preliminary assessments indicate a role for superconducting devices in millimeter and submillimeter free space power transmission systems.

Christian, Jose L., Jr.; Cull, Ronald C.

1988-01-01

164

The status of R and D for superconducting power transmission systems  

NASA Astrophysics Data System (ADS)

Many research groups in the US, Europe and the USSR worked on the development of superconducting power transmission systems in 1960's, 1970's and early 1980's. The superconducting material used was niobium or niobium-tin. A wide variety of conductor configurations, dielectric insulation and cryogenic enclosures were investigated. Systems studies to evaluate technical and economic factors were performed. Two large outdoor test facilities were constructed which provided data of interest to potential utility company users. Virtually all these projects are now closed down, mainly due to technical difficulties with the particular design chosen or due to the realization that the next development phase, the transfer of the technology into industry, will be very expensive compared to the original R and D costs. At present no funding agency sets a high priority on the development of superconducting power transmission systems.

Forsyth, E. B.

165

Portable self-contained power and cooling system  

SciTech Connect

A portable power and cooling system is described comprising: a drive unit including a combustion section, a scroll-type expander section, a scroll-type air compressor section, and a power output drive shaft, the expander and air compressor sections connected together for synchronousmovement via said power output drive shaft; said combustion section including a combustion air inlet and a combustion gas outlet, said scroll-type expander section including at least one pair of meshed axially extending involute spiral wrap members having involute centers and defining at least one expansion chamber between them that moves radially between an expander inlet zone, which is in fluid communicatino with the combustion gas outlet, and an outlet zone when one wrap member is orbited along a circular path about an orbit center relative to the other wrap member, said scroll type air compressor section including at least one pair of meshed axially extending involute spiral wrap members having involute centers and defining at least one compression chamber between them that moves radially between a compressor inlet zone and an outlet zone, which is in fluid communication with the combustion air inlet of the combustoin section, when one wrap member is orbited along a circular path relative to the other wrap member about an orbit radius, said drive connecting unit integrally connecting said one wrap member of each of said scroll-type expander and air compressor sections; means for causing combustion within said combustion chamber such that the products of combustion are expanded by said scroll-type expander section and exhausted out said expander outlet, air is drawn into said air compressor inlet zone, compressed within, expelled through said air compressor outlet zone, and delivered to said combustoin chamber and said power output shaft is rotated; a refrigeration system, a refrigerant condenser, a refrigerant expansion valve and a refrigerant evaporator, and a conduit.

McCullough, J.E.

1993-07-20

166

Modeling Single-Phase and Boiling Liquid Jet Impingement Cooling in Power Electronics  

SciTech Connect

Jet impingement has been an attractive cooling option in a number of industries over the past few decades. Over the past 15 years, jet impingement has been explored as a cooling option in microelectronics. Recently, interest has been expressed by the automotive industry in exploring jet impingement for cooling power electronics components. This technical report explores, from a modeling perspective, both single-phase and boiling jet impingement cooling in power electronics, primarily from a heat transfer viewpoint. The discussion is from the viewpoint of the cooling of IGBTs (insulated-gate bipolar transistors), which are found in hybrid automobile inverters.

Narumanchi, S. V. J.; Hassani, V.; Bharathan, D.

2005-12-01

167

USE of mine pool water for power plant cooling.  

SciTech Connect

Water and energy production issues intersect in numerous ways. Water is produced along with oil and gas, water runs off of or accumulates in coal mines, and water is needed to operate steam electric power plants and hydropower generating facilities. However, water and energy are often not in the proper balance. For example, even if water is available in sufficient quantities, it may not have the physical and chemical characteristics suitable for energy or other uses. This report provides preliminary information about an opportunity to reuse an overabundant water source--ground water accumulated in underground coal mines--for cooling and process water in electric generating facilities. The report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL), which has implemented a water/energy research program (Feeley and Ramezan 2003). Among the topics studied under that program is the availability and use of ''non-traditional sources'' of water for use at power plants. This report supports NETL's water/energy research program.

Veil, J. A.; Kupar, J. M .; Puder, M. G.

2006-11-27

168

Development of a naturally aspired thermosyphon for power amplifier cooling  

NASA Astrophysics Data System (ADS)

This paper details the early development steps of a two-phase thermosyphon thermal management solution for power amplifiers (PA) in the telecommunication industry. These components, attached to a vertical PCB within an enclosure between the RF filter and a natural or forced convection heat sink, dissipate a large amount of heat with a high heat flux density. Currently cooled by direct contact to a shared heat sink, they tend to spread heat towards other components of their board, affecting their reliability. A thermosyphon thus appear as an ideal thermal management solution to transport the heat from the power amplifiers in order to dissipate it to a remote and dedicated natural convection heat sink. In the present study, the performance and the heat spreading of a forced convection unit is measured. A thermosyphon solution is then designed with a flat vertical evaporator and a radial natural convection heat sink and condenser. The performance of the thermosyphon thermal management solution is measured and compared to the initial solution. The limits and improvement needs of the thermosyphon solution are then discussed.

Siedel, S.; Robinson, A. J.; Kempers, R.; Kerslake, S.

2014-07-01

169

Gas-cooled reactor for space power systems  

SciTech Connect

Reactor characteristics based on extensive development work on the 500-MWt reactor for the Pluto nuclear ramjet are described for space power systems useful in the range of 2 to 20 MWe for operating times of 1 y. The modest pressure drop through the prismatic ceramic core is supported at the outlet end by a ceramic dome which also serves as a neutron reflector. Three core materials are considered which are useful at temperatures up to about 2000 K. Most of the calculations are based on a beryllium oxide with uranium dioxide core. Reactor control is accomplished by use of a burnable poison, a variable-leakage reflector, and internal control rods. Reactivity swings of 20% are obtained with a dozen internal boron-10 rods for the size cores studied. Criticality calculations were performed using the ALICE Monte Carlo code. The inherent high-temperature capability of the reactor design removes the reactor as a limiting condition on system performance. The low fuel inventories required, particularly for beryllium oxide reactors, make space power systems based on gas-cooled near-thermal reactors a lesser safeguard risk than those based on fast reactors.

Walter, C.E.; Pearson, J.S.

1987-05-01

170

Thermal analysis of the forced cooled conductor for the TF (toroidal field) superconducting coils in the TIBER II ETR design  

SciTech Connect

The Tokamak Ignition/Burn Experimental Reactor (TIBER) is being designed to provide nuclear testing capabilities for first wall and blanket design concepts. The baseline design for TIBER II is to provide steady-state nuclear burn capabilities. These objectives must be met using reactor relevant components, such as state-of-the-art current drive schemes coupled with superconducting toroidal field (TF) and poloidal field (PF) coils. The design is also constrained to be cost effective, which forces the machine to be as small as possible. This last constraint limits the nuclear shielding in TIBER. Therefore, the TF coils will have a high nuclear heat load of up to 4.5 kW per coil. The cooling scheme and the thermal analysis for this design are presented.

Kerns, J.A.; Slack, D.S.; Miller, J.R.

1987-06-11

171

Temporary cooling of quasiparticles and delay in voltage response of superconducting bridges after abruptly switching on the supercritical current  

NASA Astrophysics Data System (ADS)

We revisit the problem of the dynamic response of a superconducting bridge after abruptly switching on the supercritical current. In contrast to previous theoretical works we take into account spatial gradients and use both the local temperature approach and the kinetic equation for the distribution function of quasiparticles. We find that the temperature dependence of the finite delay time td in the voltage response is model dependent and relatively large td is connected with temporary cooling of quasiparticles during decay of superconducting order parameter |?| in time. It turns out that the presence of even small inhomogeneities in the bridge or finite length of the homogenous bridge favors a local suppression of |?| during the dynamic response. It results in a decrease of the delay time, in comparison with the spatially uniform model, due to the diffusion of nonequilibrium quasiparticles from the region with locally suppressed |?|. In the case when the current density is maximal near the edge of a not very wide bridge the delay time is mainly connected with the time needed for the nucleation (entrance) of the first vortex and td could be tuned by a weak external magnetic field. We also find that a short alternating current pulse (sinusoidlike) with zero time average may result in a nonzero time-averaged voltage response where its sign depends on the phase of the ac current.

Vodolazov, D. Yu.; Peeters, F. M.

2014-09-01

172

Simulation of cooling-water discharges from power plants  

Microsoft Academic Search

Accurate simulation of the temperature distribution in a cooling lake or reservoir is often required for feasibility studies of engineering options that increase the cooling capacity of the waterbody. A three-dimensional hydrodynamic and temperature model has been developed and applied to several cooling lakes in the south-eastern United States. In this paper, the details of the modeling system are presented,

J. Wu; E. M. Buchak; J. E. Edinger; V. S. Kolluru

2001-01-01

173

Fabrication of a working Bi2223 superconducting magnet cooled by liquid nitrogen  

Microsoft Academic Search

A practical Bi-2223 superconducting magnet, working in liquid nitrogen (L.N2), was designed and fabricated. Bi-2223 tape with a critical current of 147A was prepared by a controlled overpressure (CT-OP) process at 77.3K in self-field. Ten double-pancake coils were resistively connected by copper terminals. The bore diameter was 54mm?, the magnet outer diameter was 122mm?, the height of the magnet was

E. S. Otabe; M. Kiuchi; T. Matsushita; K. Fujino; K. Ohmatsu; B. Ni

2009-01-01

174

Automatic generation control of an interconnected hydrothermal power system considering superconducting magnetic energy storage  

Microsoft Academic Search

This paper presents the analysis of automatic generation control (AGC) of an interconnected hydrothermal power system in the presence of generation rate constraints (GRCs). The improvement of AGC with the addition of a small capacity superconducting magnetic energy storage (SMES) unit in either, as well as in both the areas are studied. Time domain simulations are used to study the

Rajesh Joseph Abraham; D. Das; Amit Patra

2007-01-01

175

Instabilities above critical current region in Bi2223\\/Ag superconducting coils cooled by liquid nitrogen  

Microsoft Academic Search

A sudden drop of the coil voltage and a hysteresis of I–V curve were observed in measurement of one-layer Bi-2223\\/Ag coils cooled by liquid nitrogen at currents well above critical current region. Their temporal behavior indicates, that the improvement of the cooling and corresponding decrease of temperature after the jump takes place. To study this phenomenon we measured I–V curves

F Chovanec; P Usak

2002-01-01

176

Solar-powered\\/fuel-assisted Rankine cycle power and cooling system: simulation method and seasonal performance  

Microsoft Academic Search

The subject of this analysis is a solar cooling system based on a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100° C, and it is then superheated to about 600° C in a fossil-fuel fired superheater. The addition of about 20-26% of fuel doubles the power cycle's efficiency as compared

N. Lior; K. Koai

1982-01-01

177

Assessment of power electronic inverter cooling requirements for a rear-axle drive  

Microsoft Academic Search

The work presented in this paper is focused on determining the cooling requirement and its effect on the reliability of a power electronic inverter used in a rear-axle drive for a hybrid car. The cooling requirements are determined through electro-thermal simulations. Several comparative electro-thermal simulations are carried out for different levels of cooling, i.e. convection coefficients, power module integration and

Jonas Ottosson

2011-01-01

178

Thermoelectric cooling of microelectronic circuits and waste heat electrical power generation in a desktop personal computer  

Microsoft Academic Search

Thermoelectric cooling and micro-power generation from waste heat within a standard desktop computer has been demonstrated. A thermoelectric test system has been designed and constructed, with typical test results presented for thermoelectric cooling and micro-power generation when the computer is executing a number of different applications. A thermoelectric module, operating as a heat pump, can lower the operating temperature of

C. A. Gould; N. Y. A. Shammas; S. Grainger; I. Taylor

2011-01-01

179

A new combined cooling, heating and power system driven by solar energy  

Microsoft Academic Search

A new combined cooling, heating and power (CCHP) system is proposed. This system is driven by solar energy, which is different from the current CCHP systems with gas turbine or engine as prime movers. This system combines a Rankine cycle and an ejector refrigeration cycle, which could produce cooling output, heating output and power output simultaneously. The effects of hour

Jiangfeng Wang; Yiping Dai; Lin Gao; Shaolin Ma

2009-01-01

180

Some observations on biofouling in the cooling water conduits of a coastal power plant  

Microsoft Academic Search

Biofouling of cooling water conduits is a problem common to all coastal power stations using seawater as a heat sink. Madras Atomic Power Station has been facing the problem of fouling induced flow resistance of cooling water in its submarine tunnel leading to a drop in water level beyond design limits in the forebay. Inspection of the tunnel system by

S. Rajagopal; N. Sasikumar; Jayapaul Azariah; K. V. K. Nair

1991-01-01

181

Using Impinging Stream to Kill Algae, Fungi and Bacteria in Cooling Water of Thermal Power Plants  

Microsoft Academic Search

The growth of living organism like algae, fungi and bacteria in the cooling-water system of thermal power plants may cause biological fouling. In this paper, a novel method using impinging stream was proposed to kill algae, fungi and bacteria in cooling water of thermal power plants. Using yeast cells as an example, the method of yeast cell disruption by a

Xia Yang; Jia Guo; Yu-xin Zhou; Yuan Wu; Hong-qiang Zhang; Lin Zhang

2011-01-01

182

RF Conditioning and Testing of Fundamental Power Couplers for SNS Superconducting Cavity Production  

SciTech Connect

The Spallation Neutron Source (SNS) makes use of 33 medium beta (0.61) and 48 high beta (0.81) superconducting cavities. Each cavity is equipped with a fundamental power coupler, which should withstand the full klystron power of 550 kW in full reflection for the duration of an RF pulse of 1.3 msec at 60 Hz repetition rate. Before assembly to a superconducting cavity, the vacuum components of the coupler are submitted to acceptance procedures consisting of preliminary quality assessments, cleaning and clean room assembly, vacuum leak checks and baking under vacuum, followed by conditioning and RF high power testing. Similar acceptance procedures (except clean room assembly and baking) were applied for the airside components of the coupler. All 81 fundamental power couplers for SNS superconducting cavity production have been RF power tested at JLAB Newport News and, beginning in April 2004 at SNS Oak Ridge. This paper gives details of coupler processing and RF high power-assessed performances.

M. Stirbet; G.K. Davis; M. A. Drury; C. Grenoble; J. Henry; G. Myneni; T. Powers; K. Wilson; M. Wiseman; I.E. Campisi; Y.W. Kang; D. Stout

2005-05-16

183

At the Frontiers of Science Superconductivity and Its Electric Power Applications  

SciTech Connect

Electricity - it is one of our modern scientific miracles, and today we could not imagine living without it. But what if we could make it better? Superconductivity has the potential to do just that, by improving the capacity, quality, and reliability of products that use electricity. There has been a great deal of discussion about superconductivity in the last 10 years, but what exactly is it? In this document you will learn the definition of superconductivity, how it works, and its present and potential uses. You will also get an inside look at the challenges that scientists around the world are working to overcome in order to fully incorporate superconductivity in our everyday lives. When you turn on a lamp at home, the electric current flows - is conducted - through a wire made of copper or aluminum. Along the way, this wire resists the flow of electricity, and this resistance is something very much like friction. The resistance causes some of the electricity to be lost in the form of heat. Which means that every time you use an appliance, from a radio to a generator, you are not getting 100% of the energy that flows through it; some of it is wasted by the conductor. Superconductivity - the ability of a material to conduct electricity without losses to resistance - is a physical property inherent to a variety of metals and ceramics, much the same way magnetism is present in a variety of materials. It is dependent on temperature; that is, a material will not exhibit superconductivity until it is sufficiently cold. The necessary temperatures to induce superconductivity are well below what we might commonly consider 'cold.' They are so low, in fact, that they are measured using the Kelvin temperature scale (K). Absolute zero, or 0 K, is equal to -459 Fahrenheit (F). It is defined as the lowest temperature theoretically possible, or the complete absence of heat. In 1911, working in a laboratory in Holland, the Dutch scientist Heike Kamerlingh Onnes cooled mercury to 4 K (-452 F), almost absolute zero; at this temperature, the motion of individual atoms nearly ceased. Scientists were unsure what effect this extremely low temperature would have on resistance; most suspected resistance would increase as atomic motion slowed. However, during routine measurements of the mercury, it appeared that there was no electrical resistance. Onnes assumed his equipment was broken, but days later he confirmed that, near absolute zero, mercury did completely lose electrical resistance. Onnes had discovered superconductivity.

None

1998-07-01

184

The Use of a Solid State Analog Television Transmitter as a Superconducting Electron Gun Power Amplifier  

SciTech Connect

A solid state analog television transmitter designed for 200 MHz operation is being commissioned as a radio frequency power amplifier on the Wisconsin superconducting electron gun cavity. The amplifier consists of three separate radio frequency power combiner cabinets and one monitor and control cabinet. The transmitter employs rugged field effect transistors built into one kilowatt drawers that are individually hot swappable at maximum continuous power output. The total combined power of the transmitter system is 33 kW at 200 MHz, output through a standard coaxial transmission line. A low level radio frequency system is employed to digitally synthesize the 200 MHz signal and precisely control amplitude and phase.

J.G. Kulpin, K.J. Kleman, R.A. Legg

2012-07-01

185

Remote Measurement of Heat Flux from Power Plant Cooling Lakes  

SciTech Connect

Laboratory experiments have demonstrated a correlation between the rate of heat loss q? from an experimental fluid to the air above and the standard deviation ? of the thermal variability in images of the fluid surface. These experimental results imply that q? can be derived directly from thermal imagery by computing ?. This paper analyses thermal imagery collected over two power plant cooling lakes to determine if the same relationship exists. Turbulent boundary layer theory predicts a linear relationship between q? and ? when both forced (wind driven) and free (buoyancy driven) convection are present. Datasets derived from ground- and helicopter-based imagery collections had correlation coefficients between ? and q? of 0.45 and 0.76, respectively. Values of q? computed from a function of ? and friction velocity u* derived from turbulent boundary layer theory had higher correlations with measured values of q? (0.84 and 0.89). This research may be applicable to the problem of calculating losses of heat from the ocean to the atmosphere during high-latitude cold-air outbreaks because it does not require the information typically needed to compute sensible, evaporative, and thermal radiation energy losses to the atmosphere.

Garrett, A.; Kurzeja, R.; Villa-Aleman, E.; Bollinger, J.

2013-01-01

186

IMPACT OF THE SUN PATCH ON HEATING AND COOLING POWER EVALUATION: APPLIED TO A LOW ENERGY CELL  

E-print Network

IMPACT OF THE SUN PATCH ON HEATING AND COOLING POWER EVALUATION: APPLIED TO A LOW ENERGY CELL A-step. Heating or cooling power is compared to the power calculated with no sun patch incorporation (solar loads impact on the observed results. Keywords: sun patch, fast climatic variations, heating and cooling power

Paris-Sud XI, Université de

187

Consideration of sub-cooled LN2 circulation system for HTS power machines  

NASA Astrophysics Data System (ADS)

We consider a sub-cooled liquid nitrogen (LN) circulation system for HTS power equipment. The planned circulation system consists of a sub-cool heat exchanger (subcooler) and a circulation pump. The sub-cooler will be connected to a neon turbo- Brayton cycle refrigerator with a cooling power of 2 kW at 65 K. Sub-cooled LN will be delivered into the sub-cooler by the pump and cooled within it. Sub-cooled LN is adequate fluid for cooling HTS power equipment, because its dielectric strength is high and it supports a large critical current. However, a possibility of LN solidification in the sub-cooler is a considerable issue. The refrigerator will produce cold neon gas of about 60 K, which is lower than the nitrogen freezing temperature of 63 K. Therefore, we designed two-stage heat exchangers which are based on a plate-fin type and a tube-intube type. Process simulations of those heat exchangers indicate that sub-cooled LN is not frozen in either sub-cooler. The plate-fin type sub-cooler is consequently adopted for its reliability and compactness. Furthermore, we found that a cooling system with a Brayton refrigerator has the same total cooling efficiency as a cooling system with a Stirling refrigerator.

Yoshida, Shigeru; Hirai, Hirokazu; Nara, N.; Nagasaka, T.; Hirokawa, M.; Okamoto, H.; Hayashi, H.; Shiohara, Y.

2012-06-01

188

One Hundred Years of Superconductivity: Superconducting Materials and Electric Power Applications (465th Brookhaven Lecture)  

SciTech Connect

It was one hundred years ago this year that Dutch physicist Heike Kamerlingh Onnes discovered that by lowering the temperature of mercury to a blistering cold four degrees Kelvin, the metal became a “superconductor” and allowed electricity to flow through it with very little, if any, resistance. Fast forward one hundred years: now we are looking for new ways to store and transport energy — energy we can use to get from one place to another, stay comfortable when the weather outside is not, grow enough healthy food to feed the population, and sustain our ways of life — all while trying to protect the planet. Superconductors, with their potential to be über-energy efficient, are likely to play a crucial role in solving these challenges, and researchers at Brookhaven Lab are figuring out just how it can be done. Li will begin his talk with an overview of the first one hundred years of exploring superconductivity. He will also discuss the challenges of developing new superconductors and improving their performance for real-world energy applications, and then explain how basic science researchers at BNL are addressing those challenges.

Li, Qiang (BNL Condensed Matter Physics and Materials Science Department) [BNL Condensed Matter Physics and Materials Science Department

2011-01-19

189

The impact of high temperature superconductivity on the electric power sector  

SciTech Connect

The progress and prospects for the application of high temperature superconductivity to the Electric Power Sector has been the topic of an IEA Implementing Agreement, begun in 1990. The present Task Members are Canada, Denmark, Finland, Germany, Israel, Italy, Japan, Netherlands, Norway, Sweden, Switzerland, Turkey, United Kingdom and the United States. As a result of the Implementing Agreement, work has been done by the Operating Agent with the full participation of all the member countries. This work has facilitated the exchange of information among experts in all countries and has documented relevant assessments. Further, this work has examined the status of high amperage conductor, fault-current limiters, superconducting magnetic energy storage, cables, rotating machines, refrigeration, and studies of the power system. The Task Members find more progress toward applications than many expected five years ago and the grounds for further international collaboration to hasten the use of superconductors in the power sector, early in the 21st century.

Wolsky, A.M.

1996-01-01

190

Experimental Study on Active Cooling Systems Used for Thermal Management of High-Power Multichip Light-Emitting Diodes  

PubMed Central

The objective of this study was to develop suitable cooling systems for high-power multichip LEDs. To this end, three different active cooling systems were investigated to control the heat generated by the powering of high-power multichip LEDs in two different configurations (30 and 2 × 15?W). The following cooling systems were used in the study: an integrated multi-fin heat sink design with a fan, a cooling system with a thermoelectric cooler (TEC), and a heat pipe cooling device. According to the results, all three systems were observed to be sufficient for cooling high-power LEDs. Furthermore, it was observed that the integrated multifin heat sink design with a fan was the most efficient cooling system for a 30?W high-power multichip LED. The cooling system with a TEC and 46?W input power was the most efficient cooling system for 2 × 15?W high-power multichip LEDs. PMID:25162058

2014-01-01

191

Noise and Bandwidth Measurements of Diffusion-Cooled Nb Hot-Electron Bolometer Mixers at Frequencies Above the Superconductive Energy Gap  

NASA Technical Reports Server (NTRS)

Diffusion-cooled Nb hot-electron bolometer (HEB) mixers have the potential to simultaneously achieve high intermediate frequency (IF) bandwidths and low mixer noise temperatures for operation at THz frequencies (above the superconductive gap energy). We have measured the IF signal bandwidth at 630 GHz of Nb devices with lengths L = 0.3, 0.2, and 0.1 micrometer in a quasioptical mixer configuration employing twin-slot antennas. The 3-dB EF bandwidth increased from 1.2 GHz for the 0.3 gm long device to 9.2 GHz for the 0.1 gm long device. These results demonstrate the expected 1/L squared dependence of the IF bandwidth at submillimeter wave frequencies for the first time, as well as the largest EF bandwidth obtained to date. For the 0.1 gm device, which had the largest bandwidth, the double sideband (DSB) noise temperature of the receiver was 320-470 K at 630 GHz with an absorbed LO power of 35 nW, estimated using the isothermal method. A version of this mixer with the antenna length scaled for operation at 2.5 THz has also been tested. A DSB receiver noise temperature of 1800 plus or minus 100 K was achieved, which is about 1,000 K lower than our previously reported results. These results demonstrate that large EF bandwidth and low-noise operation of a diffusion-cooled HEB mixer is possible at THz frequencies with the same device geometry.

Wyss, R. A.; Karasik, B. S.; McGrath, W. R.; Bumble, B.; LeDuc, H.

1999-01-01

192

Chip-level spray cooling of an LD-MOSFET RF power Amplifier  

Microsoft Academic Search

We report here the application of water spray cooling directly to the top surface of a lateral diffused metal oxide semiconductor field effect transistor (LD-MOSFET) in a 500-MHz RF power amplifier. With the amplifier running in Class A, spray cooling at a flow of 0.14 l\\/min increases the output power from 66 W to 84 W, and the power-added efficiency

A. C. Cotler; E. R. Brown; V. Dhir; M. C. Shaw

2004-01-01

193

Design report for an indirectly cooled 3-m diameter superconducting solenoid for the Fermilab Collider Detector Facility  

SciTech Connect

The Fermilab Collider Detector Facility (CDF) is a large detector system designed to study anti pp collisions at very high center of mass energies. The central detector for the CDF shown employs a large axial magnetic field volume instrumented with a central tracking chamber composed of multiple layers of cylindrical drift chambers and a pair of intermediate tracking chambers. The purpose of this system is to determine the trajectories, sign of electric charge, and momenta of charged particles produced with polar angles between 10 and 170 degrees. The magnetic field volume required for tracking is approximately 3.5 m long an 3 m in diameter. To provide the desired ..delta..p/sub T/p/sub T/ less than or equal to 1.5% at 50 GeV/c using drift chambers with approx. 200..mu.. resolution the field inside this volume should be 1.5 T. The field should be as uniform as is practical to simplify both track finding and the reconstruction of particle trajectories with the drift chambers. Such a field can be produced by a cylindrical current sheet solenoid with a uniform current density of 1.2 x 10/sup 6/ A/m (1200 A/mm) surrounded by an iron return yoke. For practical coils and return yokes, both central electromagnetic and central hadronic calorimetry must be located outside the coil of the magnet. This geometry requires that the coil and the cryostat be thin both in physical thickness and in radiation and absorption lengths. This dual requirement of high linear current density and minimal coil thickness can only be satisfied using superconducting technology. In this report we describe the design for an indirectly cooled superconducting solenoid to meet the requirements of the Fermilab CDF. The components of the magnet system are discussed in the following chapters, with a summary of parameters listed in Appendix A.

Fast, R.; Grimson, J.; Kephart, R.

1982-10-01

194

Engineering development of superconducting RF linac for high-power applications  

SciTech Connect

High-power proton linacs are a promising source of neutrons for material processing and research applications. Superconducting radiofrequency (SCRF) Rf linac technology is preferred for such applications because of power efficiency. A multi-year engineering development program is underway at Los Alamos National Laboratory to demonstrate the required SCRF technology. The program consists of development of SC cavities, power couplers, and cryomodule integration. Prototypes will be built and operated to obtain performance and integration information, and for design improvement. This paper describes the scope and present status of the development program.

Dominic Chan, K.C.; Rusnak, B.; Gentzlinger, R.C.; Campbell, B.M.; Kelley, J.P. [Los Alamos National Lab., NM (United States); Safa, H. [CEA Saclay (France)

1998-12-31

195

Development and application of superconducting transformers  

NASA Astrophysics Data System (ADS)

Superconducting transformers are an important innovation for future power transmission and transportation systems. Powerful, lightweight, energy-saving and environmentally friendly they offer enormous benefits compared to their conventional counterparts. Siemens is developing a 1-MVA demonstrator transformer for laboratory testing, exhibiting innovative features like horizontal design, cabled-conductor windings and a closed cooling cycle with sub-cooled nitrogen. Being one of the most promising applications Siemens has started a programme towards the development of on-board transformers for electrical rail vehicles. This paper summarises world-wide efforts in the development of superconducting transformers and reports on the progress achieved at Siemens.

Leghissa, M.; Gromoll, B.; Rieger, J.; Oomen, M.; Neumüller, H.-W.; Schlosser, R.; Schmidt, H.; Knorr, W.; Meinert, M.; Henning, U.

2002-08-01

196

Magnetic Energy Storage System: Superconducting Magnet Energy Storage System with Direct Power Electronics Interface  

SciTech Connect

GRIDS Project: ABB is developing an advanced energy storage system using superconducting magnets that could store significantly more energy than today’s best magnetic storage technologies at a fraction of the cost. This system could provide enough storage capacity to encourage more widespread use of renewable power like wind and solar. Superconducting magnetic energy storage systems have been in development for almost 3 decades; however, past devices were designed to supply power only for short durations—generally less than a few minutes. ABB’s system would deliver the stored energy at very low cost, making it ideal for eventual use in the electricity grid as a costeffective competitor to batteries and other energy storage technologies. The device could potentially cost even less, on a per kilowatt basis, than traditional lead-acid batteries.

None

2010-10-01

197

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

198

Horizontal cryogenic bushing for the termination of a superconducting power-transmission line  

DOEpatents

A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminated the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.

Minati, K.F.; Morgan, G.H.; McNerney, A.J.; Schauer, F.

1982-07-29

199

Study on the Shimming Power Supply at room temperature for superconducting magnet  

Microsoft Academic Search

The homogeneity of superconducting magnetic field is one of the important factors determining the spectral resolution and signal-to-noise ratio of NMR spectroscopy. The active shimming is a real-time tuning for a homogeneous magnetic field. In this paper the principle of the active shimming and its process as well as the basic model of room-temperature Shimming Power Supply were investigated. A

J. Li; J. Tan; H. B. Chen; Z. Chen; Z. Y. Zheng

2010-01-01

200

Termination for a superconducting power transmission line including a horizontal cryogenic bushing  

DOEpatents

A termination for a superconducting power transmission line is disclosed which is comprised of a standard air entrance insulated vertical bushing with an elbow, a horizontal cryogenic bushing linking the pressurized cryogenic cable environment to the ambient temperature bushing and a stress cone which terminates the cable outer shield and transforms the large radial voltage gradient in the cable dielectric into a much lower radial voltage gradient in the high density helium coolant at the cold end of the cryogenic bushing.

Minati, Kurt F. (Northport, NY); Morgan, Gerry H. (Patchogue, NY); McNerney, Andrew J. (Shoreham, NY); Schauer, Felix (Upton, NY)

1984-01-01

201

Calorimeters for Precision Power Dissipation Measurements on Controlled-Temperature Superconducting Radiofrequency Samples  

SciTech Connect

Two calorimeters, with stainless steel and Cu as the thermal path material for high precision and high power versions, respectively, have been designed and commissioned for the surface impedance characterization (SIC) system at Jefferson Lab to provide low temperature control and measurement for CW power up to 22 W on a 5 cm dia. disk sample which is thermally isolated from the RF portion of the system. A power compensation method has been developed to measure the RF induced power on the sample. Simulation and experimental results show that with these two calorimeters, the whole thermal range of interest for superconducting radiofrequency (SRF) materials has been covered. The power measurement error in the interested power range is within 1.2% and 2.7% for the high precision and high power versions, respectively. Temperature distributions on the sample surface for both versions have been simulated and the accuracy of sample temperature measurements have been analysed. Both versions have the ability to accept bulk superconductors and thin film superconducting samples with a variety of substrate materials such as Al, Al{sub 2}O{sub 3}, Cu, MgO, Nb and Si.

Xiao, Binping P.; Kelley, Michael J.; Reece, Charles E.; Phillips, H. L.

2012-12-01

202

Calorimeters for precision power dissipation measurements on controlled-temperature superconducting radiofrequency samples  

NASA Astrophysics Data System (ADS)

Two calorimeters, with stainless steel and Cu as the thermal path material for high precision and high power versions, respectively, have been designed and commissioned for the 7.5 GHz surface impedance characterization system at Jefferson Lab to provide low temperature control and measurement for CW power up to 22 W on a 5 cm diameter disk sample which is thermally isolated from the radiofrequency (RF) portion of the system. A power compensation method has been developed to measure the RF induced power on the sample. Simulation and experimental results show that with these two calorimeters, the whole thermal range of interest for superconducting radiofrequency materials has been covered. The power measurement error in the interested power range is within 1.2% and 2.7% for the high precision and high power versions, respectively. Temperature distributions on the sample surface for both versions have been simulated and the accuracy of sample temperature measurements have been analyzed. Both versions have the ability to accept bulk superconductors and thin film superconducting samples with a variety of substrate materials such as Al, Al2O3, Cu, MgO, Nb, and Si.

Xiao, B. P.; Reece, C. E.; Phillips, H. L.; Kelley, M. J.

2012-12-01

203

Self-driven cooling loop for a large superconducting magnet in space  

NASA Technical Reports Server (NTRS)

Pressurized cooling loops in which superfluid helium circulation is driven by the heat being removed have been previously demonstrated in laboratory tests. A simpler and lighter version which eliminates a heat exchanger by mixing the returning fluid directly with the superfluid helium bath was analyzed. A carefully designed flow restriction must be used to prevent boiling in this low-pressure system. A candidate design for Astromag is shown that can keep the magnet below 2.0 K during magnet charging. This gives a greater margin against accidental quench than approaches that allow the coolant to warm above the lambda point. A detailed analysis of one candidate design is presented.

Mord, A. J.; Snyder, H. A.

1992-01-01

204

Thermal optimization of the helium-cooled power leads for the SSC  

Microsoft Academic Search

The optimum thermal design of the power leads for the Superconducting Super Collider (SSC) will minimize the amount of Carnot work (which is a combination of refrigeration and liquefaction work) required. This optimization can be accomplished by the judicious selection of lead length and diameter. Even though an optimum set of dimensions is found, the final design must satisfy other

J. A. Demko; W. E. Schiesser; R. Carcagno; M. McAshan; R. McConeghy

1992-01-01

205

MODEL AND BEAM BASED SETUP PROCEDURES FOR A HIGH POWER HADRON SUPERCONDUCTING LINAC  

SciTech Connect

This presentation will review methods for experimental determination of optimal operational set points in a multi-cavity superconducting high power hadron linac. A typical tuning process is based on comparison between measured data and the results of simulations from envelope and single-particle models. Presence of significant space charge effects requires simulation and measurement of bunch dynamics in 3 dimensions to ensure low loss beam transport. This is especially difficult in a superconducting linac where use of interceptive diagnostics is usually restricted because of the risk of SRF cavity surface contamination. The procedures discussed here are based on non-interceptive diagnostics such as beam position monitors and laser wires, and conventional diagnostics devices such as wire scanners and bunch shape monitors installed outside the superconducting linac. The longitudinal Twiss analysis based on the BPM signals will be described. The superconducting SNS linac tuning experience will be used to demonstrate problems and their solution for real world linac tune-up procedures

Shishlo, Andrei P [ORNL

2014-01-01

206

Package cooling designs for a dual-chip electronic package with one high power chip  

Microsoft Academic Search

Dual-chip microelectronic packages (DCP) with one high power chip are being increasingly encountered in computer and other electronic systems where a common chip carrier, whether a ceramic or an organic laminate, has a central processing unit (CPU) accompanied by a memory chip. In this study, package cooling designs are developed and presented for cooling two product applications of the DCP,

Amilcar Arvelo; Hilton Toy; K. Sikka; A. Tai; H. Longworth; Wei Zou; J. Coffin

2004-01-01

207

The cooling pond of the Chernobyl Nuclear Power Plant: A groundwater remediation case history  

Microsoft Academic Search

The cooling pond of the Chernobyl nuclear power plant was heavily contaminated as a result of the reactor accident in April 1986. From 1989 to 1993 the cooling pond represented one of the major sources of 90Sr migration from the Chernobyl site to the Dnieper River. Several attempts have been made to contain radioactive contamination within the pond. Overestimation of

Dmitri A. Bugai; Robert D. Waters; Sergei P. Dzhepo; Alexander S. Skalsk'ij

1997-01-01

208

The cooling pond of the Chernobyl nuclear power plant: A groundwater remediation case history  

Microsoft Academic Search

The cooling pond of the Chernobyl nuclear power plant was heavily contaminated as a result of the reactor accident in April 1986. From 1989 to 1993 the cooling pond represented one of the major sources of 90Sr migration from the Chernobyl site to the Dnieper River. Several attempts have been made to contain radioactive contamination within the pond. Overestimation of

Dmitri A. Bugai; Robert D. Waters; Sergei P. Dzhepo; Alexander S. Skalsk'ij

1997-01-01

209

A SELF-COOLED LIQUID BREEDER BLANKET FOR A LASER IFE POWER PLANT WITH MAGNETIC INTERVENTION  

E-print Network

A SELF-COOLED LIQUID BREEDER BLANKET FOR A LASER IFE POWER PLANT WITH MAGNETIC INTERVENTION A if an electrically resistive structural material is used. An advanced blanket based on a self- cooled liquid breeder and placement, the current HAPL strategy assumes as baseline a chamber with no protective gas. The armor

Raffray, A. René

210

WET/DRY COOLING SYSTEMS FOR FOSSIL-FUELED POWER PLANTS: WATER CONSERVATION AND PLUME ABATEMENT  

EPA Science Inventory

The report gives results of a study of technical and economic feasibilities of wet/dry cooling towers for water conservation and vapor plume abatement. Results of cost optimizations of wet/dry cooling for 1000-MWe fossil-fueled power plants are presented. Five sites in the wester...

211

Solar-powered/fuel-assisted Rankine cycle power and cooling system - Sensitivity analysis  

NASA Astrophysics Data System (ADS)

The subject of this analysis is a solar power/cooling system based on a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100 C, and it is then superheated to about 600 C in a fossil-fuel-fired superheater. The addition of about 20-26 percent of energy as fuel doubles the power cycle's efficiency as compared to organic fluid Rankine cycles operating at similar collector temperatures. A sensitivity analysis of the system's performance to the size and type of its components was performed by a transient (hourly) computer simulation over the month of August in two representative climatic regions (Washington, D.C. and Phoenix, Ariz.), and led to the description of a system configuration which provides optimal energy performance. The newly designed turbine's predicted efficiency is seen to be essentially invariant with system configuration, and has a monthly average value of about 73 percent.

Lior, N.; Koai, K.

1984-11-01

212

HIGH POWER COUPLERS AND PUSHING THE LIMITS OF SUPERCONDUCTIVE CAVITIES  

E-print Network

procedures. Generally a coupler can be defined as a device that transfers the power from the source a perfect coupler. In order to integrate a coupler in a SC cavity, the ultrahigh vacuum transition (from environment to the machine pressure) and the thermal transition (from ~300K to 2K) should be taken

Paris-Sud XI, Université de

213

Ice Thermal Storage Systems for LWR Supplemental Cooling and Peak Power Shifting  

SciTech Connect

Availability of enough cooling water has been one of the major issues for the nuclear power plant site selection. Cooling water issues have frequently disrupted the normal operation at some nuclear power plants during heat waves and long draught. The issues become more severe due to the new round of nuclear power expansion and global warming. During hot summer days, cooling water leaving a power plant may become too hot to threaten aquatic life so that environmental regulations may force the plant to reduce power output or even temporarily to be shutdown. For new nuclear power plants to be built at areas without enough cooling water, dry cooling can be used to remove waste heat directly into the atmosphere. However, dry cooling will result in much lower thermal efficiency when the weather is hot. One potential solution for the above mentioned issues is to use ice thermal storage systems (ITS) that reduce cooling water requirements and boost the plant’s thermal efficiency in hot hours. ITS uses cheap off-peak electricity to make ice and uses those ice for supplemental cooling during peak demand time. ITS is suitable for supplemental cooling storage due to its very high energy storage density. ITS also provides a way to shift large amount of electricity from off peak time to peak time. Some gas turbine plants already use ITS to increase thermal efficiency during peak hours in summer. ITSs have also been widely used for building cooling to save energy cost. Among three cooling methods for LWR applications: once-through, wet cooling tower, and dry cooling tower, once-through cooling plants near a large water body like an ocean or a large lake and wet cooling plants can maintain the designed turbine backpressure (or condensation temperature) during 99% of the time; therefore, adding ITS to those plants will not generate large benefits. For once-through cooling plants near a limited water body like a river or a small lake, adding ITS can bring significant economic benefits and avoid forced derating and shutdown during extremely hot weather. For the new plants using dry cooling towers, adding the ice thermal storage systems can effectively reduce the efficiency loss and water consumption during hot weather so that new LWRs could be considered in regions without enough cooling water. \\ This paper presents the feasibility study of using ice thermal storage systems for LWR supplemental cooling and peak power shifting. LWR cooling issues and ITS application status will be reviewed. Two ITS application case studies will be presented and compared with alternative options: one for once-through cooling without enough cooling for short time, and the other with dry cooling. Because capital cost, especially the ice storage structure/building cost, is the major cost for ITS, two different cost estimation models are developed: one based on scaling method, and the other based on a preliminary design using Building Information Modeling (BIM), an emerging technology in Architecture/Engineering/Construction, which enables design options, performance analysis and cost estimating in the early design stage.

Haihua Zhao; Hongbin Zhang; Phil Sharpe; Blaise Hamanaka; Wei Yan; WoonSeong Jeong

2010-06-01

214

Performance Analysis of XCPC Powered Solar Cooling Demonstration Project  

E-print Network

chiller. The calculated sun power is the product of totalpower provided by the sun, the power collected by the XCPCs,power tower) generally require a tracking mechanism to concentrate a large number of suns

Widyolar, Bennett

2013-01-01

215

Reliability of water-cooled high-power diode laser modules  

Microsoft Academic Search

High power diode lasers have demonstrated reliable output power of more than 50W per diode far beyond 10,000 hours. Record output power of more than 300W per diode laser bar has been reported. The improved reliability of the semiconductor material demands a review of the performance of the actively water cooled heatsink with regards to the expected lifetime. Results from

Georg Treusch; Raman Srinivasan; Dennis Brown; Robert Miller; Jim Harrison

2005-01-01

216

Study on a Highly Stabilized Power Supply for Hybrid-Magnet Superconducting Outsert  

NASA Astrophysics Data System (ADS)

The superconducting outsert of the 40 T hybrid-magnet in High Magnetic Field Laboratory (HMFL) of Chinese Academy of Sciences (CAS) requires a highly stabilized power supply. In this paper, two kinds of power supply design are briefly presented and both advantages and disadvantages are analyzed. In order to overcome the drawbacks of switching power supply, a series regulated active filter is adopted and a new design is proposed which ensures cooperative relationship between the feedback control loops of the switching converter and the series regulated active filter. Besides, unlike the traditional switching power supply, which can generate positive voltage only, this new design can also generate negative voltage which is needed in the quench protection for the superconducting magnet. In order to demonstrate the effectiveness of the methodology, a low-power prototype has been accomplished. The simulation and experiment results show that the power supply achieves high precision under the combined action of two feedback control loops. The peak-to-peak amplitude of the output ripple voltage of the prototype is 0.063%, while the peak-to-peak amplitude of the output ripple current is 120 ppm.

Wu, Jinglin; Long, Jiaojiao; Liu, Xiaoning

2014-09-01

217

EVALUATION OF EUROPEAN RIVERS FOR POWER PLANT COOLING - A POLISH RESEARCH PROJECT  

EPA Science Inventory

The report describes analytical, laboratory, and field research conducted to optimize the use of rivers, specifically in Poland, for once-through cooling of steam electric power plants. Maximum discharge and receiving water temperatures, based on biological criteria, are coupled ...

218

Fast, low-power manipulation of spin ensembles in superconducting microresonators  

SciTech Connect

We demonstrate the use of high-Q superconducting coplanar waveguide (CPW) microresonators to perform rapid manipulations on a randomly distributed spin ensemble using very low microwave power (400 nW). This power is compatible with dilution refrigerators, making microwave manipulation of spin ensembles feasible for quantum computing applications. We also describe the use of adiabatic microwave pulses to overcome microwave magnetic field (B{sub 1}) inhomogeneities inherent to CPW resonators. This allows for uniform control over a randomly distributed spin ensemble. Sensitivity data are reported showing a single shot (no signal averaging) sensitivity to 10{sup 7} spins or 3×10{sup 4}spins/?(Hz) with averaging.

Sigillito, A. J., E-mail: asigilli@princeton.edu; Malissa, H.; Tyryshkin, A. M.; Houck, A. A.; Lyon, S. A. [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Riemann, H.; Abrosimov, N. V. [Institut für Kristallzüchtung, D-12489 Berlin (Germany); Becker, P. [Physikalisch-Technische Bundesanstalt, D-38116 Braunschweig (Germany); Pohl, H.-J. [VITCON Projectconsult GMBH, D-07745 Jena (Germany); Thewalt, M. L. W. [Department of Physics, Simon Fraser University, Burnaby, British Columbia V5A 1S6 (Canada); Itoh, K. M. [School of Fundamental Science and Technology, Keio University, Yokohama, Kanagawa 2238522 (Japan); Morton, J. J. L. [London Centre for Nanotechnology, University College London, London WC1H 0AH (United Kingdom); Schuster, D. I. [Department of Physics and James Franck Institute, University of Chicago, Chicago, Illinois 60637 (United States)

2014-06-02

219

1. Cooling water is one-third of US water usage Basic approach: (a) estimate power consumption, from which you estimate cooling water usage  

E-print Network

1. Cooling water is one-third of US water usage Basic approach: (a) estimate power consumption) Water for power consumption I happen to know that total energy usage is roughly 10 kW per person, from which you estimate cooling water usage and compare with (b) estimate of other water usage. (a

Nimmo, Francis

220

Sport fishery potential of power plant cooling ponds: Final report  

SciTech Connect

This research was undertaken to determine if cooling ponds could serve as habitat for several coolwater fish species and also to evaluate the potential use of cooling ponds as nursery areas for receiving waters. The work was conducted on two cooling ponds in northern Illinois. Walleye (Stizostedion vitreum), muskellunge (Esox masquinongy), striped bass (Morone saxatilis) fingerlings, and adult threadfin shad (Dorosoma petenense) were stocked into both cooling ponds. The hybrids between the striped bass and white bass (M. chrysops) had been previously stocked into Collins Pond. Smallmouth bass (Micropterus dolomieui) fingerlings and larval striped bass and walleye were stocked in Dresden Pond. Several sampling techniques including seining, electrofishing, and rotenoning were used to monitor growth and survival of stocked species. In addition, escapement of stocked and indigenous species was monitored at the Dresden Pond spillway. Walleye, muskellunge, striped bass and hybrid striped bass exhibited excellent growth in Collins Pond as did smallmouth bass in Dresden Pond. One of the primary differences between an open system (such as Dresden Pond) and a closed system (such as Collins Pond) is the potential that the open system has to serve as a fish nursery area for receiving waters. The stocking of ''coolwater'' species in a closed type system such as Collins Pond is an effective way to control and maintain selected sport species. Dresden Pond was not open to public fishing during this study, but Collins Pond developed an excellent sport fishery as a result of these stockings.

Heidinger, R.C.; Lewis, W.M.

1986-10-01

221

Dry cooling towers as condensers for geothermal power plants  

Microsoft Academic Search

The aim of this paper is to present scaling laws for a dry natural draft cooling tower by modelling the heat exchanger and the tower supports as a porous medium. Porous medium modelling of the tube bundles that allows a vigorous theoretical analysis of the problem is adopted. Scale analysis is used as the theoretical tool to study the problem

Kamel Hooman

2010-01-01

222

Technical analysis of a river basin-based model of advanced power plant cooling technologies for mitigating water management challenges  

Microsoft Academic Search

Thermoelectric power plants require large volumes of water for cooling, which can introduce drought vulnerability and compete with other water needs. Alternative cooling technologies, such as cooling towers and hybrid wet-dry or dry cooling, present opportunities to reduce water diversions. This case study uses a custom, geographically resolved river basin-based model for eleven river basins in the state of Texas

Ashlynn S. Stillwell; Mary E. Clayton; Michael E. Webber

2011-01-01

223

Flux-transfer losses in helically wound superconducting power cables  

SciTech Connect

Minimization of ac losses is essential for economic operation of high-temperature superconductor (HTS) ac power cables. A favorable configuration for the phase conductor of such cables has two counter-wound layers of HTS tape-shaped wires lying next to each other and helically wound around a flexible cylindrical former. However, if magnetic materials such as magnetic substrates of the tapes lie between the two layers, or if the winding pitch angles are not opposite and essentially equal in magnitude to each other, current distributes unequally between the two layers. Then, if at some point in the ac cycle the current of either of the two layers exceeds its critical current, a large ac loss arises from the transfer of flux between the two layers. A detailed review of the formalism, and its application to the case of paramagnetic substrates including the calculation of this flux-transfer loss, is presented.

Clem, John R.; Malozemoff, A.P.

2013-06-25

224

Solving LFC problem in an interconnected power system using superconducting magnetic energy storage  

NASA Astrophysics Data System (ADS)

This paper proposes the combination of a load frequency control (LFC) with superconducting magnetic energy storage (SMES) to solve the LFC problem in interconnected power systems. By using this combination, the speed damping of frequency and tie-line power flow deviations is considerably increased. A new control strategy of SMES is proposed in this paper. The problem of determining optimal parameters of PID and SMES control loop is considered as an optimization problem and a pattern search algorithm (PS) optimization is employed to solve it. The simulation results show that if an SMES unit is installed in an interconnected power system, in addition to eliminating oscillations and deviations, the settling time in the frequency and tie-line power flow responses is considerably reduced.

Farahani, Mohsen; Ganjefar, Soheil

2013-04-01

225

The natural draught, indirect dry cooling system for the 6 times 686 MWe Kendal Power Station, RSA  

Microsoft Academic Search

The use of dry cooling systems in power plants is a relatively new development and limited to only a few applications worldwide. The locations in question are those at which wet cooling system could not be used economically due to a shortage of making-up water. The power plants using dry cooling systems which have been built to date world- wide,

B. Trage; A. J. Ham; T. C. Vicary

1990-01-01

226

Utilization of municipal wastewater for cooling in thermoelectric power plants  

SciTech Connect

A process simulation model has been developed using Aspen Plus(R) with the OLI (OLI System, Inc.) water chemistry model to predict water quality in the recirculating cooling loop utilizing secondary- and tertiary-treated municipal wastewater as the source of makeup water. Simulation results were compared with pilot-scale experimental data on makeup water alkalinity, loop pH, and ammonia evaporation. The effects of various parameters including makeup water quality, salt formation, NH{sub 3} and CO{sub 2} evaporation mass transfer coefficients, heat load, and operating temperatures were investigated. The results indicate that, although the simulation model can capture the general trends in the loop pH, experimental data on the rates of salt precipitation in the system are needed for more accurate prediction of the loop pH. It was also found that stripping of ammonia and carbon dioxide in the cooling tower can influence the cooling loop pH significantly. The effects of the NH{sub 3} mass transfer coefficient on cooling loop pH appear to be more significant at lower values (e.g., k{sub NH3}< 4×10{sup -3} m/s) when the makeup water alkalinity is low (e.g., <90 mg/L as CaCO{sub 3}). The effect of the CO{sub 2} mass transfer coefficient was found to be significant only at lower alkalinity values (e.g., k{sub CO2}<4×10{{sup -6} m/s).

Safari, Iman; Walker, Michael E.; Hsieh, Ming-Kai; Dzombak, David A.; Liu, Wenshi; Vidic, Radisav D.; Miller, David C.; Abbasian, Javad

2013-09-01

227

Method and system for powering and cooling semiconductor lasers  

DOEpatents

A semiconductor laser system includes a diode laser tile. The diode laser tile includes a mounting fixture having a first side and a second side opposing the first side and an array of semiconductor laser pumps coupled to the first side of the mounting fixture. The semiconductor laser system also includes an electrical pulse generator thermally coupled to the diode bar and a cooling member thermally coupled to the diode bar and the electrical pulse generator.

Telford, Steven J; Ladran, Anthony S

2014-02-25

228

Monolayer graphene dispersion and radiative cooling for high power LED.  

PubMed

Molecular fan, a radiative cooling by thin film, has been developed and its application for compact electronic devices has been evaluated. The enhanced surface emissivity and heat dissipation efficiency of the molecular fan coating are shown to correlate with the quantization of lattice modes in active nanomaterials. The highly quantized G and 2D bands in graphene are achieved by our dispersion technique, and then incorporated in an organic-inorganic acrylate emulsion to form a coating assembly on heat sinks (for LED and CPU). This water-based dielectric layer coating has been formulated and applied on metal core printed circuit boards. The heat dissipation efficiency and breakdown voltage are evaluated by a temperature-monitoring system and a high-voltage breakdown tester. The molecular fan coating on heat dissipation units is able to decrease the equilibrium junction temperature by 29.1?° C, while functioning as a dielectric layer with a high breakdown voltage (>5 kV). The heat dissipation performance of the molecular fan coating applied on LED devices shows that the coated 50 W LED gives an enhanced cooling of 20% at constant light brightness. The schematics of monolayer graphene dispersion, undispersed graphene platelet, and continuous graphene sheet are illustrated and discussed to explain the mechanisms of radiative cooling, radiative/non-radiative, and non-radiative heat re-accumulation. PMID:24008305

Hsiao, Tun-Jen; Eyassu, Tsehaye; Henderson, Kimberly; Kim, Taesam; Lin, Chhiu-Tsu

2013-10-01

229

Energy penalty analysis of possible cooling water intake structurerequirements on existing coal-fired power plants.  

SciTech Connect

Section 316(b) of the Clean Water Act requires that cooling water intake structures must reflect the best technology available for minimizing adverse environmental impact. Many existing power plants in the United States utilize once-through cooling systems to condense steam. Once-through systems withdraw large volumes (often hundreds of millions of gallons per day) of water from surface water bodies. As the water is withdrawn, fish and other aquatic organisms can be trapped against the screens or other parts of the intake structure (impingement) or if small enough, can pass through the intake structure and be transported through the cooling system to the condenser (entrainment). Both of these processes can injure or kill the organisms. EPA adopted 316(b) regulations for new facilities (Phase I) on December 18, 2001. Under the final rule, most new facilities could be expected to install recirculating cooling systems, primarily wet cooling towers. The EPA Administrator signed proposed 316(b) regulations for existing facilities (Phase II) on February 28, 2002. The lead option in this proposal would allow most existing facilities to achieve compliance without requiring them to convert once-through cooling systems to recirculating systems. However, one of the alternate options being proposed would require recirculating cooling in selected plants. EPA is considering various options to determine best technology available. Among the options under consideration are wet-cooling towers and dry-cooling towers. Both types of towers are considered to be part of recirculating cooling systems, in which the cooling water is continuously recycled from the condenser, where it absorbs heat by cooling and condensing steam, to the tower, where it rejects heat to the atmosphere before returning to the condenser. Some water is lost to evaporation (wet tower only) and other water is removed from the recirculating system as a blow down stream to control the building up of suspended and dissolved solids. Makeup water is withdrawn, usually from surface water bodies, to replace the lost water. The volume of makeup water is many times smaller than the volume needed to operate a once-through system. Although neither the final new facility rule nor the proposed existing facility rule require dry cooling towers as the national best technology available, the environmental community and several States have supported the use of dry-cooling technology as the appropriate technology for addressing adverse environmental impacts. It is possible that the requirements included in the new facility rule and the ongoing push for dry cooling systems by some stakeholders may have a role in shaping the rule for existing facilities. The temperature of the cooling water entering the condenser affects the performance of the turbine--the cooler the temperature, the better the performance. This is because the cooling water temperature affects the level of vacuum at the discharge of the steam turbine. As cooling water temperatures decrease, a higher vacuum can be produced and additional energy can be extracted. On an annual average, once-through cooling water has a lower temperature than recirculated water from a cooling tower. By switching a once-through cooling system to a cooling tower, less energy can be generated by the power plant from the same amount of fuel. This reduction in energy output is known as the energy penalty. If a switch away from once-through cooling is broadly implemented through a final 316(b) rule or other regulatory initiatives, the energy penalty could result in adverse effects on energy supplies. Therefore, in accordance with the recommendations of the Report of the National Energy Policy Development Group (better known as the May 2001 National Energy Policy), the U.S. Department of Energy (DOE), through its Office of Fossil Energy, National Energy Technology Laboratory (NETL), and Argonne National Laboratory (ANL), has studied the energy penalty resulting from converting plants with once-through cooling to wet towers or indirect-dry towers. Five l

Veil, J. A.; Littleton, D. J.; Gross, R. W.; Smith, D. N.; Parsons, E.L., Jr.; Shelton, W. W.; Feeley, T. J.; McGurl, G. V.

2006-11-27

230

ORNL Superconducting Technology Program for Electric Power Systems, Annual Report for FY 1998  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy to develop the science and technology base needed by U.S. industry for commercial development of electric power applications of high temperature superconductivity. The two major elements of this program are wire development and applications development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from recent open literature publications, presentations, and information prepared for the FY 1998 Annual Program Review held July 20-22, 1998. Aspects of ORNL's work that were presented at the Applied Superconductivity Conference (September 1998) are included in this report, as well. This ORNL program is highly leveraged by the staff and other resources of U.S. industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to cooperative projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer with U.S. industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high temperature superconductor wire and wire-using systems.

Hawsey, R.A.; Murphy, A.W.

1999-04-01

231

Performance optimization of dry-cooling systems for power plants through SQP methods  

Microsoft Academic Search

In this study the application of modern optimization techniques to obtain cost optimal design and performance of dry-cooling systems for power plant applications, is illustrated. The Sequential Quadratic Programming (SQP) method, as well as a SQP decomposition technique are implemented. It is shown that through the proper application of these powerful optimization strategies and careful tailoring of the well-constructed optimization

A. E. Conradie; J. D. Buys; D. G. Kröger

1998-01-01

232

The prospect of mox fuel based Pb Bi cooled small nuclear power reactors  

Microsoft Academic Search

Safety performance of MOX fuel based PbBi cooled small fast power reactors has been analyzed and discussed. Though the thermal conductivity of MOX fuel is not large relative to that of nitride or metal fuel, but by proper combination of relatively small power density and relatively large natural circulation it can compensate fuel temperature decrease with coolant temperature increase smartly

Zaki Su'ud; Bakrie Arbie; Sedyartomo S

2005-01-01

233

Integrated three-dimensional module heat exchanger for power electronics cooling  

SciTech Connect

Embodiments discussed herein are directed to a power semiconductor packaging that removes heat from a semiconductor package through one or more cooling zones that are located in a laterally oriented position with respect to the semiconductor package. Additional embodiments are directed to circuit elements that are constructed from one or more modular power semiconductor packages.

Bennion, Kevin; Lustbader, Jason

2013-09-24

234

Rate of cooling and power consumption of farm milk coolers  

E-print Network

milk usinm asit tcr1;. a'. er :;th wit::- out ice bank - mnruier load, i, ". . . rch 20, 196'd. '1'he ac:blent tem; er ature was ~O al ~ 6 & ~ 4 ~ 0 ~ i ~ 0 ~ ~ 0 ~ * ~ ~ ~ I V Typical data sheet for rate of cooling miiir using' crit... or electrical z. ofrizzez' tion (:". ith or . ittz;. tcr an". ilk agitation) gives sufficiently . . -:t=c of coolin- fo f; rzz nuzT. o=es. . . ovic::-. , !, ni~ zlz, snd Soyd (-") 9 ve tize folio:. in; infor- 19'!6 'oaccrain~ far;z ail. '. coclizzr z 1...

McCardle, Arthur, Jr

1952-01-01

235

High-power magnetron transmitter as an RF source for superconducting linear accelerators  

E-print Network

A concept of a high-power magnetron transmitter for operation within a wideband control feedback loop in phase and amplitude is presented. This transmitter is proposed to drive Superconducting RF (SRF) cavities for intensity-frontier GeV-scale proton/ion linacs. The transmitter performance at the dynamic control was verified in experiments with CW, S-Band, 1 kW magnetrons. The wideband control of magnetrons, required for the superconducting linacs, was realized using the magnetrons, injection-locked by the phase-modulated signals. The capabilities of the magnetrons injection-locked by the phase-modulated signals and adequateness for feeding of SRF cavities were verified by measurements of the transfer function magnitude characteristics of single and 2-cascade magnetrons, by measurements the magnetrons phase performance and by measurements of spectra of the carrier frequency. At the ratio of power of locking signal to output power less than -13 dB (in 2-cascade scheme per magnetron, respectively) we demonstrat...

Kazakevich, Grigory; Flanagan, Gene; Marhauser, Frank; Yakovlev, Vyacheslav; Chase, Brian; Lebedev, Valeri; Nagaitsev, Sergei; Pasquinelli, Ralph; Solyak, Nikolay; Quinn, Kenneth; Wolff, Daniel; Pavlov, Viatcheslav

2014-01-01

236

COOLING WATER ISSUES AND OPPORTUNITIES AT U.S. NUCLEAR POWER PLANTS  

SciTech Connect

This report has been prepared for the Department of Energy, Office of Nuclear Energy (DOE-NE), for the purpose of providing a status report on the challenges and opportunities facing the U.S. commercial nuclear energy industry in the area of plant cooling water supply. The report was prompted in part by recent Second Circuit and Supreme Court decisions regarding cooling water system designs at existing thermo-electric power generating facilities in the U.S. (primarily fossil and nuclear plants). At issue in the courts have been Environmental Protection Agency regulations that define what constitutes “Best Technology Available” for intake structures that withdraw cooling water that is used to transfer and reject heat from the plant’s steam turbine via cooling water systems, while minimizing environmental impacts on aquatic life in nearby water bodies used to supply that cooling water. The report was also prompted by a growing recognition that cooling water availability and societal use conflicts are emerging as strategic energy and environmental issues, and that research and development (R&D) solutions to emerging water shortage issues are needed. In particular, cooling water availability is an important consideration in siting decisions for new nuclear power plants, and is an under-acknowledged issue in evaluating the pros and cons of retrofitting cooling towers at existing nuclear plants. Because of the significant ongoing research on water issues already being performed by industry, the national laboratories and other entities, this report relies heavily on ongoing work. In particular, this report has relied on collaboration with the Electric Power Research Institute (EPRI), including its recent work in the area of EPA regulations governing intake structures in thermoelectric cooling water systems.

Gary Vine

2010-12-01

237

Subtask 5.10 - Testing of an Advanced Dry Cooling Technology for Power Plants  

SciTech Connect

The University of North Dakota’s Energy & Environmental Research Center (EERC) is developing a market-focused dry cooling technology that is intended to address the key shortcomings of conventional dry cooling technologies: high capital cost and degraded cooling performance during daytime temperature peaks. The unique aspect of desiccant dry cooling (DDC) is the use of a hygroscopic working fluid—a liquid desiccant—as a heat-transfer medium between a power plant’s steam condenser and the atmosphere. This configuration enables a number of beneficial features for large-scale heat dissipation to the atmosphere, without the consumptive use of cooling water. The overall goal of this project was to accurately define the performance and cost characteristics of DDC to determine if further development of the concept is warranted. A balanced approach of modeling grounded in applied experimentation was pursued to substantiate DDC-modeling efforts and outline the potential for this technology to cool full-scale power plants. The resulting analysis shows that DDC can be a lower-cost dry cooling alternative to an air-cooled condenser (ACC) and can even be competitive with conventional wet recirculating cooling under certain circumstances. This project has also highlighted the key technological steps that must be taken in order to transfer DDC into the marketplace. To address these issues and to offer an extended demonstration of DDC technology, a next-stage project should include the opportunity for outdoor ambient testing of a small DDC cooling cell. This subtask was funded through the EERC–U.S. Department of Energy (DOE) Joint Program on Research and Development for Fossil Energy-Related Resources Cooperative Agreement No. DE-FC26-08NT43291. Nonfederal funding was provided by the Wyoming State Legislature under an award made through the Wyoming Clean Coal Technologies Research Program.

Martin, Christopher; Pavlish, John

2013-09-30

238

Geographic, technologic, and economic analysis of using reclaimed water for thermoelectric power plant cooling.  

PubMed

Use of reclaimed water-municipal wastewater treatment plant effluent-in nonpotable applications can be a sustainable and efficient water management strategy. One such nonpotable application is at thermoelectric power plants since these facilities require cooling, often using large volumes of freshwater. To evaluate the geographic, technologic, and economic feasibility of using reclaimed water to cool thermoelectric power plants, we developed a spatially resolved model of existing power plants. Our model integrates data on power plant and municipal wastewater treatment plant operations into a combined geographic information systems and optimization approach to evaluate the feasibility of cooling system retrofits. We applied this broadly applicable methodology to 125 power plants in Texas as a test case. Results show that sufficient reclaimed water resources exist within 25 miles of 92 power plants (representing 61% of capacity and 50% of generation in our sample), with most of these facilities meeting both short-term and long-term water conservation cost goals. This retrofit analysis indicates that reclaimed water could be a suitable cooling water source for thermoelectric power plants, thereby mitigating some of the freshwater impacts of electricity generation. PMID:24625241

Stillwell, Ashlynn S; Webber, Michael E

2014-04-15

239

Analysis of large dry cooling towers with power-law heat exchanger performance  

Microsoft Academic Search

An analysis is presented for heat exchanger area, tower exit area, and exchanger tube length and number, for heat exchangers in large dry cooling towers, having performance parameters given by powers of Reynolds number, but otherwise under very general cooling-cycle constraints. The calculation method is illustrated for a ''spin-fin'' heat exchanger which, in a tube size of about ³\\/â in.,

F. K. Moore; C. C. Ndubizu

1976-01-01

240

Performance evaluation of dry-cooling systems for power plant applications  

Microsoft Academic Search

The performance evaluation of dry-cooling systems rely heavily on the ability to model the physical phenomena of the system. A sophisticated equation-based model, consisting of the conservation equations (energy, mass, momentum) and engineering design relations, is presented to model the dry-cooling systems performance for power plant applications. The implementation of this model gives rise to practical and reliable design methods

A. E. Conradie; D. G. Kröger

1996-01-01

241

Energy penalty analysis of possible cooling water intake structurerequirements on existing coal-fired power plants  

Microsoft Academic Search

Section 316(b) of the Clean Water Act requires that cooling water intake structures must reflect the best technology available for minimizing adverse environmental impact. Many existing power plants in the United States utilize once-through cooling systems to condense steam. Once-through systems withdraw large volumes (often hundreds of millions of gallons per day) of water from surface water bodies. As the

J. A. Veil; D. J. Littleton; R. W. Gross; D. N. Smith; Parsons E. L. Jr; W. W. Shelton; T. J. Feeley; G. V. McGurl

2006-01-01

242

The development of a solar-powered residential heating and cooling system  

NASA Technical Reports Server (NTRS)

Efforts to demonstrate the engineering feasibility of utilizing solar power for residential heating and cooling are described. These efforts were concentrated on the analysis, design, and test of a full-scale demonstration system which is currently under construction at the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville, Alabama. The basic solar heating and cooling system under development utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating and water heating, and an absorption cycle air conditioner for space cooling.

1974-01-01

243

Performance Improvement of a Power Conversion Module by Liquid MicroJet Impingement Cooling  

Microsoft Academic Search

Liquid micro-jet array impingement cooling of a power conversion module with 12 power switching devices (six insulated gate bipolar transistors and six diodes) is investigated. The 1200-V\\/150-A module converts dc input power to variable frequency, variable voltage three-phase ac output to drive a 50HP three-phase induction motor. The silicon devices are attached to a packaging layer [direct bonded copper (DBC)],

Avijit Bhunia; Sriram Chandrasekaran; Chung-Lung Chen

2007-01-01

244

Wet\\/dry cooling and cooling tower blowdown disposal in synthetic fuel and steam-electric power plants. Final report jul 77-dec 78  

Microsoft Academic Search

This report extends the results of a previous study dealing with the detailed determination of consumptive water use and wet-solids residuals for coal and oil shale conversion plants and coal-fired steam-electric power generation plants located in the western United States. The present report addresses the problem of determining the degree to which wet cooling, dry cooling, or wet\\/dry cooling should

H. Gold; D. J. Goldstein

1979-01-01

245

Power applications of high-temperature superconductivity: Variable speed motors, current switches, and energy storage for end use  

SciTech Connect

The objective of this project is to conduct joint research and development activities related to certain electric power applications of high-temperature superconductivity (HTS). The new superconductors may allow development of an energy-efficient switch to control current to variable speed motors, superconducting magnetic energy storage (SMES) systems, and other power conversion equipment. Motor types that were considered include induction, permanent magnet, and superconducting ac motors. Because it is impractical to experimentally alter certain key design elements in radial-gap motors, experiments were conducted on an axial field superconducting motor prototype using 4 NbTi magnets. Superconducting magnetic energy storage technology with 0.25--5 kWh stored energy was studied as a viable solution to short duration voltage sag problems on the customer side of the electric meter. The technical performance characteristics of the device wee assembled, along with competing technologies such as active power line conditioners with storage, battery-based uninterruptible power supplies, and supercapacitors, and the market potential for SMES was defined. Four reports were prepared summarizing the results of the project.

Hawsey, R.A. [Oak Ridge National Lab., TN (United States); Banerjee, B.B.; Grant, P.M. [Electric Power Research Inst., Palo Alto, CA (United States)

1996-08-01

246

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Cost-Benefit Analysis for Radwaste Systems for Light-Water-Cooled Nuclear Power Reactors...Cost-Benefit Analysis for Radwaste Systems for Light-Water-Cooled Nuclear Power Reactors...gaseous radwaste system components for light water nuclear power reactors....

2013-10-25

247

Dynamical behaviour of superconducting resonators under readout-frequency, readout-power, and signal-power switching  

NASA Astrophysics Data System (ADS)

The sensitivities, saturation powers, and response times of Kinetic Inductance Detectors depend on the degree to which the quasiparticle and phonon temperatures differ when readout and signal power are applied. Previously, we proposed a model for saturation in KIDs, and found that hysteretic switching, which is seen experimentally, emerges from the model in a natural way. Here we extend our work, and show through a diagrammatic rep- resentation of operating-point trajectories that output pulse shapes can be calculated for non-hysteretic and hysteretic changes of state driven by readout-frequency, readout-power, and signal-power pulses. The work has several applications: (i) Understanding quasiparticle and phonon relaxation, and their dependence on film and substrate thickness. (ii) Recovering quasiparticle cooling functions from measurements. (iii) Understanding the relationship between optimum readout power and device and material parameters. (iv) Characterising the time-dependent behaviour of photon-counting KIDs, including nonlinearity and pile up.

Thompson, Sarah E.; Withington, Stafford; Goldie, David

2012-09-01

248

A passive cooling system proposal for multifunction and high-power displays  

NASA Astrophysics Data System (ADS)

Flat panel displays are conventionally cooled by internal natural convection, which constrains the possible rate of heat transfer from the panel. On one hand, during the last few years, the power consumption and the related cooling requirement for 1080p displays have decreased mostly due to energy savings by the switch to LED backlighting and more efficient electronics. However, on the other hand, the required cooling rate recently started to increase with new directions in the industry such as 3D displays, and ultra-high-resolution displays (recent 4K announcements and planned introduction of 8K). In addition to these trends in display technology itself, there is also a trend to integrate consumer entertainment products into displays with the ultimate goal of designing a multifunction device replacing the TV, the media player, the PC, the game console and the sound system. Considering the increasing power requirement for higher fidelity in video processing, these multifunction devices tend to generate very high heat fluxes, which are impossible to dissipate with internal natural convection. In order to overcome this obstacle, instead of active cooling with forced convection that comes with drawbacks of noise, additional power consumption, and reduced reliability, a passive cooling system relying on external natural convection and radiation is proposed here. The proposed cooling system consists of a heat spreader flat heat pipe and aluminum plate-finned heat sink with anodized surfaces. For this system, the possible maximum heat dissipation rates from the standard size panels (in 26-70 inch range) are estimated by using our recently obtained heat transfer correlations for the natural convection from aluminum plate-finned heat sinks together with the surface-to-surface radiation. With the use of the proposed passive cooling system, the possibility of dissipating very high heat rates is demonstrated, hinting a promising green alternative to active cooling.

Tari, Ilker

2013-03-01

249

Compact fluid cooled power converter supporting multiple circuit boards  

DOEpatents

A 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, in conjunction with other packaging features may form 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.

Radosevich, Lawrence D.; Meyer, Andreas A.; Beihoff, Bruce C.; Kannenberg, Daniel G.

2005-03-08

250

USE of mine pool water for power plant cooling  

Microsoft Academic Search

Water and energy production issues intersect in numerous ways. Water is produced along with oil and gas, water runs off of or accumulates in coal mines, and water is needed to operate steam electric power plants and hydropower generating facilities. However, water and energy are often not in the proper balance. For example, even if water is available in sufficient

J. A. Veil; J. M. Kupar; M. G. Puder

2006-01-01

251

POWER PLANT COOLING WATER CHLORINATION IN NORTHERN CALIFORNIA  

EPA Science Inventory

A survey was conducted of chlorination practices at five power plants owned and operated by the Pacific Gas and Electric Company. Frequency and duration of chlorination varied significantly from plant to plant and was controlled analytically by the orthotolidine and/or amperometr...

252

Adaptive Environmentally Contained Power and Cooling IT Infrastructure for the Data Center  

SciTech Connect

The objectives of this program were to research and develop a fully enclosed Information Technology (IT) rack system for 100 kilowatts (KW) of IT load that provides its own internal power and cooling with High Voltage Alternating Current (HVAC defined as 480 volt) and chilled water as the primary inputs into the system and accepts alternative energy power sources such as wind and solar. For maximum efficiency, internal power to the IT equipment uses distributed High Voltage Direct Current power (HVDC defined as 360-380 volt) from the power source to the IT loads. The management scheme aggressively controls energy use to insure the best utilization of available power and cooling resources. The solution incorporates internal active management controls that not only optimizes the system environment for the given dynamic IT loads and changing system conditions, but also interfaces with data center Building Management Systems (BMS) to provide a complete end-to-end view of power and cooling chain. This technology achieves the goal of a Power Usage Effectiveness (PUE) of 1.25, resulting in a 38% reduction in the total amount of energy needed to support a 100KW IT load compared to current data center designs.

Mann, Ron; Chavez, Miguel, E.

2012-06-27

253

High power density self-cooled lithium-vanadium blanket.  

SciTech Connect

A self-cooled lithium-vanadium blanket concept capable of operating with 2 MW/m{sup 2} surface heat flux and 10 MW/m{sup 2} neutron wall loading has been developed. The blanket has liquid lithium as the tritium breeder and the coolant to alleviate issues of coolant breeder compatibility and reactivity. Vanadium alloy (V-4Cr-4Ti) is used as the structural material because it can accommodate high heat loads. Also, it has good mechanical properties at high temperatures, high neutron fluence capability, low degradation under neutron irradiation, good compatibility with the blanket materials, low decay heat, low waste disposal rating, and adequate strength to accommodate the electromagnetic loads during plasma disruption events. Self-healing electrical insulator (CaO) is utilized to reduce the MHD pressure drop. A poloidal coolant flow with high velocity at the first wall is used to reduce the peak temperature of the vanadium structure and to accommodate high surface heat flux. The blanket has a simple blanket configuration and low coolant pressure to reduce the fabrication cost, to improve the blanket reliability, and to increase confidence in the blanket performance. Spectral shifter, moderator, and reflector are utilized to improve the blanket shielding capability and energy multiplication, and to reduce the radial blanket thickness. Natural lithium is used to avoid extra cost related to the lithium enrichment process.

Gohar, Y.; Majumdar, S.; Smith, D.

1999-07-01

254

From BCS to Vortices: A 40 Year Personal Journey through Superconductivity from Basic Research to Power Applications  

NASA Astrophysics Data System (ADS)

A century has passed since the discovery of superconductivity in Leiden followed 75 years later by the Great Leap Forward in Zuerich.ootnotetext"20th Anniversary of the Woodstock of Physics," APS March Meeting 2007, Denver, CO. This talk will chronicle the author's trajectory through the science and technology of superconductivity first taking off with his IBM career in fundamental research on organic and layered copper oxide perovskite superconductors to a final landing at EPRI to explore applications of the latter to the electric power industry. Although many fundamental mysteries remain with respect to the copper and iron compounds, especially regarding the BCS pairing mechanism, nonetheless a significant number of successful demonstrations of cables, rotating machinery, storage and power conditioning equipment employing both low-and high-TC superconducting materialsootnotetextP. M. Grant, IEEE Trans. Appl. Supercon. 7, 112 (1997). have been undertaken worldwide since the decade of the 1960s to the present. However, massive application to the power industry has yet to take place or be inserted into utility long-range planning cycles.ootnotetextP. M. Grant, "Superconductivity in Power Applications," submitted to the ICEC-ICMC 2010 Conference Proceedings. Although there will certainly be a relatively small number of opportunistic deployments in those situations where superconductivity has a compelling advantage over conventional technology, its time will more likely await a future revolution in energy and electricity infrastructure such as a symbiosisootnotetextP. M. Grant, C. Starr and T. J. Overbye, "A Power Grid for the Hydrogen Economy," Scientific American, July 2006, p.76. of nuclear and hydrogen with superconductivity. Perhaps the distant future will even deliver the dreamootnotetextP. M. Grant, Physics Today, May 1998. of a room temperature superconductor.

Grant, Paul M.

2011-03-01

255

Oxygen plants for coal gasification: Experience at the Cool Water GCC (gasification combined cycle) Power Plant: Final report  

Microsoft Academic Search

This report presents the results of a study conducted by Airco-BOC for EPRI to assess performance of the Cool Water Oxygen Plant as it relates to the Cool Water Coal Gasification Program's requirements and evaluate alternate supply arrangements for future larger gasifier based combined cycle power plants. The Cool Water Oxygen Plant is the first application of a dedicated oxygen

R. A. Petras; R. A. Mostello; A. P. Ko

1987-01-01

256

Impact of Hybrid Wet/Dry Cooling on Concentrating Solar Power Plant Performance  

SciTech Connect

This paper examines the sensitivity of Rankine cycle plant performance to dry cooling and hybrid (parallel) wet/dry cooling combinations with the traditional wet-cooled model as a baseline. Plants with a lower temperature thermal resource are more sensitive to fluctuations in cooling conditions, and so the lower temperature parabolic trough plant is analyzed to assess the maximum impact of alternative cooling configurations. While low water-use heat rejection designs are applicable to any technology that utilizes a Rankine steam cycle for power generation, they are of special interest to concentrating solar power (CSP) technologies that are located in arid regions with limited water availability. System performance is evaluated using hourly simulations over the course of a year at Daggett, CA. The scope of the analysis in this paper is limited to the power block and the heat rejection system, excluding the solar field and thermal storage. As such, water used in mirror washing, maintenance, etc., is not included. Thermal energy produced by the solar field is modeled using NREL's Solar Advisor Model (SAM).

Wagner, M. J.; Kutscher, C.

2010-01-01

257

A modular gas-cooled cermet reactor system for planetary base power  

SciTech Connect

Fission nuclear power is foreseen as the source for electricity in planetary colonization and exploration. A six module gas-cooled, cermet-fueled reactor is proposed that can meet the design objectives. The highly enriched core is compact and can operate at high temperature for a long life. The helium coolant powers six modular Brayton cycles that compare favorably with the SP-100-based Brayton cycle.

Jahshan, S.N.; Borkowski, J.A. (Idaho National Engineering Laboratory, EG G Idaho, P.O. Box 1625, MS 1575, Idaho Falls, Idaho 83415-1575 (United States))

1993-01-15

258

Solar-powered systems for cooling, dehumidification and air-conditioning  

Microsoft Academic Search

This paper describes current trends in solar-powered air conditioning, which has seen renewed interest in recent years due to the growing awareness of global warming and other environmental problems. Closed-cycle heat-powered cooling devices are based mainly on absorption chillers, a proven technology employing LiBr–water as the working fluid pair. Recent developments in gas-fired systems of this type make available double-

Gershon Grossman

2002-01-01

259

Characterization of Chlorination By-products in Cooling Effluents of Coastal Nuclear Power Stations  

Microsoft Academic Search

In power stations, the cooling effluents are chlorinated to avoid excessive biofouling. Yet, this disinfecting treatment leads to the formation of halogenated by-products. In spite of possible toxicity of such compounds towards aquatic organisms, there is an evident lack of information on the formation of halogenated compounds in chlorinated seawater samples. So, this study was undertaken to identify and quantify

Anne-Sophie Allonier; Michel Khalanski; ValÉrie Camel; Alain Bermond

1999-01-01

260

Systems approach to financial appraisal of greenhouse heating with power plant cooling water  

Microsoft Academic Search

The low-grade waste heat contained in power plant condenser cooling water (CCW) is a virtually untapped resource with potential for reducing heating costs of the greenhouse industry. Some commercial development is occurring, but the lack of a model for valuation and pricing of heat from CCW is an impediment to commercialization. A framework is needed to assist growers in estimating

Burch

1985-01-01

261

The emergence of insects from a British River warmed by power station cooling-water  

Microsoft Academic Search

During a programme of research on the fauna of the River Severn around Ironbridge Power Station, the emergence patterns of resident insect species were studied upstream and downstream of the cooling-water outfalls. This paper describes the traps used to catch emerging adult insects and relates their overall performance, total catches and species selectivity, to the physical characteristics of the river.

T. E. Langford; J. R. Daffern

1975-01-01

262

The emergence of insects from a British River, warmed by Power Station Cooling-Water  

Microsoft Academic Search

As a result of some field observations and laboratory experiments, a number of authors (see text) have suggested that insects living in rivers, even slightly heated by power station cooling water, may have their life-cycles altered sufficiently to lead to the elimination of species owing to early emergence into a lethally cold air, shorter emergence periods, disrupted mating behaviour, or

T. E. Langford

1975-01-01

263

ORNL superconducting technology program for electric power systems. Annual report for FY 1993  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the US Department of Energy`s Office of Energy Efficiency and Renewable Energy to develop the technology base needed by US industry for commercial development of electric power applications of high-temperature superconductivity. The two major elements of this program are conductor development and applications development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from information prepared for the FY 1993 Annual Program Review held July 28--29, 1993. This ORNL program is highly leveraged by the staff and other resources of US industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to industrial competitiveness projects with private companies. Interlaboratory teams are also in place on a number of industry-driven projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer to US industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high-temperature superconductor wire and wire products.

Hawsey, R.A. [comp.

1994-04-01

264

ORNL Superconducting Technology Program for Electric Power Systems: Annual Report for FY 1999  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy to develop the science and technology base needed by U.S. industry for development of electric power applications of high-temperature superconductivity. The two major elements of this program are wire development and applications development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from recent open literature publications, presentations, and information prepared for the FY 1999 Annual Program Review held July 26-28, 1999. Aspects of ORNL's work that were presented at the International Cryogenic Materials Conference and the Cryogenic Engineering Conference (July 1999) are included in this report, as well. This ORNL program is highly leveraged by the staff and other resources of U.S. industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to cooperative projects with private companies. Interlaboratory teams are also in place on a number of industry-driven projects. Working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer with U.S. industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high-temperature superconductor wire and wire-using systems.

Hawsey, R.A.

2000-06-13

265

ORNL Superconducting Technology Program for Electric Power Systems, Annual Report for FY 1999  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy to develop the science and technology base needed by U.S. industry for development of electric power applications of high-temperature superconductivity. The two major elements of this program are wire development and applications development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from recent open literature publications, presentations, and information prepared for the FY 1999 Annual Program Review held July 26--28, 1999. Aspects of ORNL's work that were presented at the International Cryogenic Materials Conference and the Cryogenic Engineering Conference (July 1999) are included in this report, as well. This ORNL program is highly leveraged by the staff and other resources of U.S. industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to cooperative projects with private companies. Interlaboratory teams are also in place on a number of industry-driven projects. Working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer with U.S. industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high-temperature superconductor wire and wire-using systems.

Hawsey, R.A.; Murphy, A.W

2000-04-01

266

ORNL Superconducting Technology Program for electric power systems. Annual report for FY 1996  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the US Department of Energy`s Office of Energy Efficiency and Renewable Energy to develop the science and technology base needed by US industry for commercial development of electric power applications of high temperature superconductivity. The two major elements of this program are wire development and applications development. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from recent open literature publications, presentations, and information prepared for the FY 1996 Annual Program Review held July 31 and August 1, 1996. This ORNL program is highly leveraged by the staff and other resources of US industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to cooperative projects with private companies. Interlaboratory teams are also in place on a number of industry-driven projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer with US industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high temperature superconductor wire and wire-using systems.

Koncinski, W.S. [ed.; Hawsey, R.A. [comp.

1997-05-01

267

ORNL Superconducting Technology Program for electric power systems: Annual report for FY 1997  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the US Department of Energy`s Office of Energy Efficiency and Renewable Energy to develop the science and technology base needed by US industry for commercial development of electric power applications of high temperature superconductivity. The two major elements of this program are wire development and applications development. This document describes the major research and developments activities for this program together with related accomplishments. The technical progress reported was summarized from recent open literature publications, presentations, and information prepared for the FY 1997 Annual Program Review held July 21--23, 1997. This ORNL program is highly leveraged by the staff and other resources of US industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to cooperative projects with private companies. Interlaboratory teams are also in place on a number of industry-driven projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer with US industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high temperature superconductor wire and wire-using systems.

Koncinski, W.S.; O`Hara, L.M. [eds.; Hawsey, R.A.; Murphy, A.W. [comps.

1998-03-01

268

First High Temperature Superconducting ECRIS  

SciTech Connect

The first High Temperature Superconducting Electron Cyclotron Resonance Ion Source (HTS-ECRIS) called PKDELIS has been developed as a collaborative project. The source has been designed for suitable use on a high voltage platform with minimum requirements of electrical power and water cooling. The design is based on the required A/q of {approx} 7 for the High Current Injector (HCI) of the Superconducting Linear Accelerator (SC-LINAC) at Nuclear Science Centre and to provide relatively higher beam currents of multiply charged ions. High Temperature Superconducting coils (Bi-2223) have been chosen to reduce the power and cooling requirements for obtaining large axial magnetic fields corresponding to a frequency of 18 GHz. The HTS coils are operated in a superconducting mode in a temperature range of about 20 to 22 K using Gifford-McMahon type cryo-refrigerators. A 36 element hexapole was designed using NdFeB to obtain higher fields at the chamber wall. The source is tested thoroughly by producing beams of carbon, oxygen, neon, argon, xenon, tantalum and lead at various charge states having analysed current up to 2 mA. The detailed design aspects and test results are presented.

Kanjilal, D.; Rodrigues, G.O.; Kumar, P.; Safvan, C.P.; Rao, U.K.; Mandal, A.; Roy, A. [Nuclear Science Centre, Aruna Asaf Ali Marg, New Delhi - 110067 (India); Bieth, C.; Kantas, S. [Pantechnik, 14000 CAEN (France); Sortais, P. [Laboratoire de Physique Subatomique et de Cosmologie, Grenoble (France)

2005-03-15

269

Performance analysis of radiation cooled dc transmission lines for high power space systems  

NASA Technical Reports Server (NTRS)

As space power levels increase to meet mission objectives and also as the transmission distance between power source and load increases, the mass, volume, power loss, and operating voltage and temperature become important system design considerations. This analysis develops the dependence of the specific mass and percent power loss on hte power and voltage levels, transmission distance, operating temperature and conductor material properties. Only radiation cooling is considered since the transmission line is assumed to operate in a space environment. The results show that the limiting conditions for achieving low specific mass, percent power loss, and volume for a space-type dc transmission line are the permissible transmission voltage and operating temperature. Other means to achieve low specific mass include the judicious choice of conductor materials. The results of this analysis should be immediately applicable to power system trade-off studies including comparisons with ac transmission systems.

Schwarze, G. E.

1985-01-01

270

Determination method of equivalent insulation test voltage at room temperature for high temperature superconducting power apparatus with coil structure  

Microsoft Academic Search

This paper deals with the determination method of the equivalent insulation test voltage at room temperature that secures the reliability of the cryogenic electrical insulation of the high temperature superconducting (HTS) power apparatus. The high voltage test is related to the apparatus with coil structure at the stages of its development, manufacturing and shipment. In the test method, the equivalent

M. Hara; T. Kurihara; T. Nishioka; J. Suehiro; H. Okamoto

2004-01-01

271

Construction of two powered hybrid magnets, each with resistive inner coils and a superconducting outer coil is  

E-print Network

Construction of two powered hybrid magnets, each with resistive inner coils and a superconducting outer coil is occurring as parallel activities at the National High Magnetic Field Laboratory (MagLab). The Series-Connected Hybrid (SCH) magnet systems demonstrate two different applications for high-field hybrid

Weston, Ken

272

Economic Operation of Long Distances Power Networks Using On-line Control of Superconducting Magnetic Energy Storage  

Microsoft Academic Search

This paper investigates a two-purpose application for the superconducting magnetic energy storage (SMES) in order to remove its economic barriers for a wide spread promotion in power systems. A practical realization of the control method using the locally measurable signals is considered. A simulation case study is conducted to verify the performance of the proposed application. The results prove that

Seyed Mohammad; SADEGH ZADEH

2007-01-01

273

Superconductors for superconducting magnets  

NASA Astrophysics Data System (ADS)

Even in 1913 Kamerlingh Onnes envisioned the use of superconductors to create powerful magnetic fields well beyond the capability provided by cooling normal metals with liquid helium. Only some "bad places" in his Hg and Pb wires seemed to impede his first attempts at this dream, one that he imagined would be resolved in a few weeks of effort. In fact, of course, resolution required another 50 years and development of both a true understanding of the difference between type I and type II superconductors and the discovery of compounds such as Nb3Sn that could remain superconducting to fields as high as 30 T. And then indeed, starting in the 1960s, Onnes's dreams were comfortably surpassed. In the last 45 years virtually all superconducting magnets have been made from just two Nb-base materials, Nb-Ti and Nb3Sn. Now it seems that a new generation of magnets based on cuprate high temperature superconductors with fields well above 30 T are possible using Bi-Sr-Ca-Cu-O and the RE-Ba-Cu-O compounds. We hope that a first demonstration of this possibility will be an all-superconducting 32 T magnet with RE-Ba-Cu-O insert that we are building for NHMFL users. The magnet application potential of this new generation of superconducting conductors will be discussed.

Larbalestier, David

2011-03-01

274

Peak power reduction and energy efficiency improvement with the superconducting flywheel energy storage in electric railway system  

NASA Astrophysics Data System (ADS)

This paper proposes an application of the 100 kWh superconducting flywheel energy storage systems to reduce the peak power of the electric railway system. The electric railway systems have high-power characteristics and large amount of regenerative energy during vehicles’ braking. The high-power characteristic makes operating cost high as the system should guarantee the secure capacity of electrical equipment and the low utilization rate of regenerative energy limits the significant energy efficiency improvement. In this paper, it had been proved that the peak power reduction and energy efficiency improvement can be achieved by using 100 kWh superconducting flywheel energy storage systems with the optimally controlled charging or discharging operations. Also, economic benefits had been assessed.

Lee, Hansang; Jung, Seungmin; Cho, Yoonsung; Yoon, Donghee; Jang, Gilsoo

2013-11-01

275

Operation of the 30 MJ superconducting magnetic energy storage system in the Bonneville Power Administration Electrical Grid  

SciTech Connect

The 30 MJ superconducting magnetic energy storage (SMES) system was installed in the Bonneville Power Administration (BPA) Tacoma Substation in 1982 to 1983. Operation of the unit since that time has been for over 1200 hours. Specific tests to explore the SMES system's thermal and electrical characteristics and the control functions were conducted. The coil heat load with current modulation was determined. A converter with two 6-pulse bridges interfaces the superconducting coil to the power bus. Equal bridge voltage amplitude and constant reactive power modes of operation of the system were run with computer control of the SCR bridge firing angles. Coil energy dump tests were performed. Electrical grid system response to SMES modulation was observed, and full power SMES modulation was undertaken.

Rogers, J.D.; Boenig, H.J.; Schermer, R.I.; Hauer, J.F.

1984-01-01

276

Organohalogen products from chlorination of cooling water at nuclear power stations  

SciTech Connect

Eight nuclear power units at seven locations in the US were studied to determine the effects of chlorine, added as a biocide, on the composition of cooling water discharge. Water, sediment and biota samples from the sites were analyzed for total organic halogen and for a variety of organohalogen compounds. Haloforms were discharged from all plants studied, at concentrations of a few ..mu..g/L (parts-per-billion). Evidence was obtained that power plants with cooling towers discharge a significant portion of the haloforms formed during chlorination to the atmosphere. A complex mixture of halogenated phenols was found in the cooling water discharges of the power units. Cooling towers can act to concentrate halogenated phenols to levels approaching those of the haloforms. Examination of samples by capillary gas chromatography/mass spectrometry did not result in identification of any significant concentrations of lipophilic base-neutral compounds that could be shown to be formed by the chlorination process. Total concentrations of lipophilic (Bioabsorbable) and volatile organohalogen material discharged ranged from about 2 to 4 ..mu..g/L. Analysis of sediment samples for organohalogen material suggests that certain chlorination products may accumulate in sediments, although no tissue bioaccumulation could be demonstrated from analysis of a limited number of samples. 58 references, 25 figures, 31 tables.

Bean, R.M.

1983-10-01

277

Development of passive dry cooling system for power plants in arid land  

SciTech Connect

Availability of large amounts of cooling water is essential for steam power plants. In inland arid areas, gas turbines are usually used for electric power generation at low efficiency and high operation costs. Dry cooling towers are another option but they are not effective with high ambient temperature. This work explores the use of radiative cooling for power plants and large refrigeration plants in inland arid areas. The work done consists of small scale experiments, mathematical models, a survey of the suitable materials, and a prototype experiment. This article presents the prototype experiment. The mathematical modeling was presented by the authors in Solar Energy 48(5), 279-286 (1992). A prototype experimental pond, 10m x 25m x 1m, covered with a painted white aluminum sheet was designed, constructed, and tested. The pond was divided into two layers. The experiment was carried out from January to June. Temperatures in the pond at different sections and depths, net radiation, and weather data were measured. At night the results showed an average heat rejection by radiation of 50 W/m[sup 2]. These results were comparable with the results of the mathematical model. The net result of the experiment was positive. It demonstrated the suitability of the covered pond as a heat rejection system in place where a sufficient amount of cooling water was not available.

Sabbagh, J.A.; Khalifa, A.M.A.; Olwi, I.A. (King Abdulaziz Univ., Jeddah (Saudi Arabia))

1993-12-01

278

Simulation of chip-size electrocaloric refrigerator with high cooling-power density  

NASA Astrophysics Data System (ADS)

The large electrocaloric effect that found in ferroelectric polymers creates unique opportunity for developing high performance chip scale solid state refrigerator. This letter presents a finite volume simulation study and shows that by employing solid state regenerators and the micro-heat pumping mechanism used in the thermoacoustic cooling, a compact Electrocaloric Oscillatory Refrigeration (ECOR) device can be realized. The simulation results demonstrate that a 1 cm-long ECOR device can provide 9 W/cm3 volumetric cooling power density at 20 K temperature span. By tuning the device parameters in the model, the ECOR can reach more than 50% of the Carnot efficiency.

Gu, Haiming; Craven, Brent; Qian, Xiaoshi; Li, Xinyu; Cheng, Ailan; Zhang, Q. M.

2013-03-01

279

Advanced high-cooling power 2-stage Gifford-McMahon refrigerator systems  

NASA Astrophysics Data System (ADS)

This paper describes the development of high-cooling power systems by making use of multiple cold head operation with a minimized number of compressor units. These advanced cooling systems were investigated for optimization and their Carnot efficiencies were analyzed. Test series were performed to monitor and rank some of their critical operation parameters. Operating envelopes for different cold head / compressor configurations were defined for applications in various VLT instruments. This new concept of providing high pressure helium as a service point for a large number of detached cold heads is a first step towards a new cryogenic facility concept for the E-ELT.

Jakob, Gerd; Lizon, Jean-Louis

2010-07-01

280

Design and operation of the 30-MJ superconducting magnetic-storage system on the Bonneville Power Administration bus  

SciTech Connect

A superconducting magnetic-energy-storage (SMES) unit is suitable for power-system stabilization because it can provide positive damping by absorbing or releasing energy with a relatively fast response time, 10 ms. In the fall of 1982, an SMES unit was installed at the Tacoma Substation of the Bonneville Power Administration as an experiment in monitoring, predicting and improving system stability. This paper reports principally on the system testing.

Schermer, R.I.; Barron, M.H.; Boenig, H.J.; Brown, R.R.; Criscuolo, A.L.; Cumming, C.J.; Dean, J.W.; Hassenzahl, W.V.; Rogers, J.D.; Seamons, M.J.

1983-01-01

281

A gas-cooled cermet reactor system for planetary base power  

SciTech Connect

Fission nuclear power is foreseen as the source for electricity in colonization exploration. A gas-cooled, cermet-fueled reactor is proposed that can meet many of the design objectives. The highly enriched core is compact and can operate at high temperature for a long life. The helium coolant powers a Brayton cycle that compares well with the SP-100-based Brayton cycle. The power cycle can be upgraded further under certain siting-related conditions by the addition of a low temperature Rankine cycle.

Jahshan, S.N.; Borkowski, J.A.

1992-01-01

282

A gas-cooled cermet reactor system for planetary base power  

SciTech Connect

Fission nuclear power is foreseen as the source for electricity in colonization exploration. A gas-cooled, cermet-fueled reactor is proposed that can meet many of the design objectives. The highly enriched core is compact and can operate at high temperature for a long life. The helium coolant powers a Brayton cycle that compares well with the SP-100-based Brayton cycle. The power cycle can be upgraded further under certain siting-related conditions by the addition of a low temperature Rankine cycle.

Jahshan, S.N.; Borkowski, J.A.

1992-08-01

283

Development of fundamental power coupler for high-current superconducting RF cavity  

SciTech Connect

Brookhaven National Laboratory took a project of developing a 704 MHz five-cell superconducting RF cavity for high-current linacs, including Energy Recovery Linac (ERL) for planned electron-hadron collider eRHIC. The cavity will be fed by a high-power RF amplifier using a coaxial Fundamental Power Coupler (FPC), which delivers 20 kW of CW RF power to the cavity. The design of FPC is one of the important aspects as one has to take into account the heat losses dissipated on the surface of the conductor by RF fields along with that of the static heat load. Using a simple simulation model we show the temperature profile and the heat load dissipated along the coupler length. To minimize the heat load on FPC near the cavity end, a thermal intercept is required at an appropriate location on FPC. A 10 K intercept was chosen and its location optimized with our simulation code. The requirement on the helium gas flow rate for the effective heat removal from the thermal intercept is also discussed.

Jain P.; Belomestnykh, S.; Ben-Zvi, I.; Xu, W.

2012-05-20

284

Use of Produced Water in Recirculated Cooling Systems at Power Generating Facilities  

SciTech Connect

Tree ring studies indicate that, for the greater part of the last three decades, New Mexico has been relatively 'wet' compared to the long-term historical norm. However, during the last several years, New Mexico has experienced a severe drought. Some researchers are predicting a return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters to supplement current fresh water supplies for power plant operation and cooling and other uses. The U.S. Department of Energy's National Energy Technology Laboratory sponsored three related assessments of water supplies in the San Juan Basin area of the four-corner intersection of Utah, Colorado, Arizona, and New Mexico. These were (1) an assessment of using water produced with oil and gas as a supplemental supply for the San Juan Generating Station (SJGS); (2) a field evaluation of the wet-surface air cooling (WSAC) system at SJGS; and (3) the development of a ZeroNet systems analysis module and an application of the Watershed Risk Management Framework (WARMF) to evaluate a range of water shortage management plans. The study of the possible use of produced water at SJGS showed that produce water must be treated to justify its use in any reasonable quantity at SJGS. The study identified produced water volume and quality, the infrastructure needed to deliver it to SJGS, treatment requirements, and delivery and treatment economics. A number of produced water treatment alternatives that use off-the-shelf technology were evaluated along with the equipment needed for water treatment at SJGS. Wet surface air-cooling (WSAC) technology was tested at the San Juan Generating Station (SJGS) to determine its capacity to cool power plant circulating water using degraded water. WSAC is a commercial cooling technology and has been used for many years to cool and/or condense process fluids. The purpose of the pilot test was to determine if WSAC technology could cool process water at cycles of concentration considered highly scale forming for mechanical draft cooling towers. At the completion of testing, there was no visible scale on the heat transfer surfaces and cooling was sustained throughout the test period. The application of the WARMF decision framework to the San Juan Basis showed that drought and increased temperature impact water availability for all sectors (agriculture, energy, municipal, industry) and lead to critical shortages. WARMF-ZeroNet, as part of the integrated ZeroNet decision support system, offers stakeholders an integrated approach to long-term water management that balances competing needs of existing water users and economic growth under the constraints of limited supply and potential climate change.

C. McGowin; M. DiFilippo; L. Weintraub

2006-06-30

285

Environmental problems associated with decommissioning the Chernobyl Nuclear Power Plant Cooling Pond.  

PubMed

Decommissioning of nuclear power plants and other nuclear fuel cycle facilities associated with residual radioactive contamination of their territories is an imperative issue. Significant problems may result from decommissioning of cooling ponds with residual radioactive contamination. The Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond is one of the largest self-contained water reservoirs in the Chernobyl region and Ukrainian and Belorussian Polesye region. The 1986 ChNPP Reactor Unit Number Four significantly contaminated the ChNPP Cooling Pond. The total radionuclide inventory in the ChNPP Cooling Pond bottom deposits are as follows: ¹³?Cs: 16.28 ± 2.59 TBq; ??Sr: 2.4 ± 0.48 TBq; and ²³?+²??Pu: 0.00518 ± 0.00148 TBq. The ChNPP Cooling Pond is inhabited by over 500 algae species and subspecies, over 200 invertebrate species, and 36 fish species. The total mass of the living organisms in the ChNPP Cooling Pond is estimated to range from about 60,000 to 100,000 tons. The territory adjacent to the ChNPP Cooling Pond attracts many birds and mammals (178 bird species and 47 mammal species were recorded in the Chernobyl Exclusion Zone). This article describes several options for the ChNPP Cooling Pond decommissioning and environmental problems associated with its decommissioning. The article also provides assessments of the existing and potential exposure doses for the shoreline biota. For the 2008 conditions, the estimated total dose rate values were 11.4 40 ?Gy h?¹ for amphibians, 6.3 ?Gy h?¹ for birds, 15.1 ?Gy h?¹ for mammals, and 10.3 ?Gy h?¹ for reptiles, with the recommended maximum dose rate being equal to 40 ?Gy h?¹. However, drying the ChNPP Cooling Pond may increase the exposure doses to 94.5 ?Gy h?¹ for amphibians, 95.2 ?Gy h?¹ for birds, 284.0 ?Gy h?¹ for mammals, and 847.0 ?Gy h?¹ for reptiles. All of these anticipated dose rates exceed the recommended values. PMID:20938234

Oskolkov, B Ya; Bondarkov, M D; Gaschak, S P; Maksymenko, A M; Maksymenko, V M; Martynenko, V I; Farfán, E B; Jannik, G T; Marra, J C

2010-11-01

286

Solar-powered\\/fuel-assisted Rankine-cycle power and cooling system: Simulation method and seasonal performance  

Microsoft Academic Search

The subject of this analysis is a solar cooling system based on a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100°C, and it is then superheated to about 600°C in a fossil-fuel-fired superheater. The addition of about 20-26 percent of fuel doubles the power cycle's efficiencyas compared to organic Rankine

N. Lior; K. Koai

1984-01-01

287

Cooling Power Density of SiGe/Si Superlattice Micro Refrigerators Gehong Zeng, Xiaofeng Fan, Chris LaBounty, Edward Croke2  

E-print Network

Cooling Power Density of SiGe/Si Superlattice Micro Refrigerators Gehong Zeng, Xiaofeng Fan, Chris Experiments were carried out to determine the cooling power density of SiGe/Si superlattice microcoolers by integrating thin film metal resistor heaters on the cooling surface. By evaluating the maximum cooling

Bowers, John

288

Prospects for the medium- and long-term development of China`s electric power industry and analysis of the potential market for superconductivity technology  

SciTech Connect

First of all, overall economic growth objectives in China are concisely and succinctly specified in this report. Secondly, this report presents a forecast of energy supply and demand for China`s economic growth for 2000--2050. In comparison with the capability of energy construction in China in the future, a gap between supply and demand is one of the important factors hindering the sustainable development of Chain`s economy. The electric power industry is one of China`s most important industries. To adopt energy efficiency through high technology and utilizing energy adequately is an important technological policy for the development of China`s electric power industry in the future. After briefly describing the achievements of China`s electric power industry, this report defines the target areas and policies for the development of hydroelectricity and nuclear electricity in the 2000s in China, presents the strategic position of China`s electric power industry as well as objectives and relevant plans of development for 2000--2050. This report finds that with the discovery of superconducting electricity, the discovery of new high-temperature superconducting (HTS) materials, and progress in materials techniques, the 21st century will be an era of superconductivity. Applications of superconductivity in the energy field, such as superconducting storage, superconducting transmission, superconducting transformers, superconducting motors, its application in Magneto-Hydro-Dynamics (MHD), as well as in nuclear fusion, has unique advantages. Its market prospects are quite promising. 12 figs.

Li, Z. [Bob Lawrence and Associates, Inc., Alexandria, VA (United States)

1998-05-01

289

Power-flow control and transient-stability enhancement of a large-scale wind power generation system using a superconducting magnetic energy storage (SMES) unit  

Microsoft Academic Search

This paper proposes a novel scheme using a superconducting magnetic energy-storage (SMES) unit to simultaneously perform both power-flow control and transient stability improvement of a large-scale wind power generation system (WPGS) subject to severe wind fluctuations. A complete system model based on a synchronously rotating reference frame for the studied WPGS combined with the proposed SMES unit is derived and

Shiang-Shong Chen; Li Wang; Zhe Chen; Wei-Jen Lee

2008-01-01

290

Macro-channel cooled high power fiber coupled diode lasers exceeding 1.2kW of output power  

NASA Astrophysics Data System (ADS)

We report on a new series of fiber coupled diode laser modules exceeding 1.2kW of single wavelength optical power from a 400um / 0.2NA fiber. The units are constructed from passively cooled laser bars as opposed to other comparably powered, commercially available modules that use micro-channel heat-sinks. Micro-channel heat sinks require cooling water to meet demanding specifications and are therefore prone to failures due to contamination and increase the overall cost to operate and maintain the laser. Dilas' new series of high power fiber coupled diode lasers are designed to eliminate micro channel coolers and their associated failure mechanisms. Low-smile soldering processes were developed to maximize the brightness available from each diode laser bar. The diode laser brightness is optimally conserved using Dilas' recently developed propriety laser bar stacking geometry and optics. A total of 24 bars are coupled into a single fiber core using a polarization multiplexing scheme. The modular design permits further power scaling through wavelength multiplexing. Other customer critical features such as industrial grade fibers, pilot beams, fiber interlocks and power monitoring are standard features on these modules. The optical design and the beam parameter calculations will be presented to explain the inherit design trade offs. Results for single and dual wavelengths modules will be presented.

Koenning, Tobias; Alegria, Kim; Wang, Zuolan; Segref, Armin; Stapleton, Dean; Faßbender, Wilhelm; Flament, Marco; Rotter, Karsten; Noeske, Axel; Biesenbach, Jens

2011-03-01

291

Microwave power coupler for a superconducting multiple-cell cavity for accelerator application and its testing procedures  

SciTech Connect

Superconducting cavity resonators offer the advantage of high field intensity for a given input power, making them an attractive contender for particle accelerator applications. Power coupling into a superconducting cavity employed in a particle accelerator requires unique provisions to maintain high vacuum and cryogenic temperature on the cavity side, while operating with ambient conditions on the source side. Components introduced to fulfill mechanical requirements must show negligible obstruction of the propagation of the microwave with absence of critical locations that may give rise to electron multipaction, leading to a multiple section design, instead of an aperture, a probe, or a loop structure as found in conventional cavities. A coaxial power coupler for a superconducting multiple-cell cavity at 3.9 GHz has been developed. The cavity is intended to be employed as an accelerator to provide enhanced electron beam quality in a free-electron laser in Hamburg (FLASH) user facility. The design of the coupler called for two windows to sustain high vacuum in the cavity and two bellows to accommodate mechanical dimensional changes resulting from cryogenics. Suppression of multipacting was accomplished by the choice of conductor dimensions and materials with low second yield coefficients. Prior to integration with the cavity, the coupler was tested for intrinsic properties in a back-to-back configuration and conditioned for high-power operation with increasing power input. Maximum incident power was measured to be 61 kW. When integrated with the superconducting cavity, a loaded quality factor of 9 x 10{sup 5} was measured by transient method. Coupler return loss and insertion loss were estimated to be around -21 dB and -0.2 dB, respectively.

Li, Jianjian; /IIT, Chicago

2008-12-01

292

Progress in development of high temperature superconducting wire for electric power applications  

SciTech Connect

The technology of high temperature superconductivity has gone beyond mere scientific curiosity and into the manufacturing environment. Single lengths of multifilamentary wire are now produced that are over 200 meters long and that carry over 13 amperes at 77 K. Short-sample critical current densities approach 5 x 10{sup 4} A/cm{sup 2} at 77 K. Conductor requirements such as high critical current density in a magnetic field, strain-tolerant sheathing materials, and other engineering properties are addressed. A new process for fabricating round BSCCO-2212 wire has produced wires with critical current densities as high as 165,000 A/cm{sup 2} at 4.2 K and 53,000 A/cm{sup 2} at 40 K. This process eliminates the costly, multiple pressing and rolling steps that are commonly used to develop texture in the wires. New multifilamentary wires with strengthened sheathing materials have shown improved yield strengths up to a factor of five better than those made with pure silver. Many electric power devices require the wire to be formed into coils for production of strong magnetic fields. Requirements for coils and magnets for electric power applications are described.

Hawsey, R.A. [Oak Ridge National Lab., TN (United States); Sokolowski, R.S.; Haldar, P. [Intermagnetics General Corp., Latham, NY (United States); Motowidlo, L.R. [IGC Advanced Superconductors, Waterbury, CT (United States)

1994-12-31

293

Development of practical high temperature superconducting wire for electric power applications  

SciTech Connect

The technology of high temperature superconductivity has gone from beyond mere scientific curiosity into the manufacturing environment. Single lengths of multifilamentary wire are now produced that are over 200 meters long and that carry over 13 amperes at 77 K. Short-sample critical current densities approach 5 {times} 10{sup 4} A/cm{sup 2} at 77 K. Conductor requirements such as high critical current density in a magnetic field, strain-tolerant sheathing materials, and other engineering properties are addressed. A new process for fabricating round BSCCO-2212 wire has produced wires with critical current densities as high as 165,000 A/cm{sup 2} at 4.2 K and 53,000 A/cm{sup 2} at 40 K. This process eliminates the costly, multiple pressing and rolling steps that are commonly used to develop texture in the wires. New multifilamentary wires with strengthened sheathing materials have shown improved yield strengths up to a factor of five better than those made with pure silver. Many electric power devices require the wire to be formed into coils for production of strong magnetic fields. Requirements for coils and magnets for electric power applications are described.

Hawsey, R.A. [Oak Ridge National Lab., TN (United States); Sokolowski, R.S.; Haldar, P. [Intermagnetics General Corp., Latham, NY (United States); Motowidlo, L.R. [IGC/Advanced Superconductors, Inc., Waterbury, CT (United States)

1994-09-01

294

Development of practical high temperature superconducting wire for electric power application  

NASA Technical Reports Server (NTRS)

The technology of high temperature superconductivity has gone from beyond mere scientific curiousity into the manufacturing environment. Single lengths of multifilamentary wire are now produced that are over 200 meters long and that carry over 13 amperes at 77 K. Short-sample critical current densities approach 5 x 104 A/sq cm at 77 K. Conductor requirements such as high critical current density in a magnetic field, strain-tolerant sheathing materials, and other engineering properties are addressed. A new process for fabricating round BSCCO-2212 wire has produced wires with critical current densities as high as 165,000 A/sq cm at 4.2 K and 53,000 A/sq cm at 40 K. This process eliminates the costly, multiple pressing and rolling steps that are commonly used to develop texture in the wires. New multifilamentary wires with strengthened sheathing materials have shown improved yield strengths up to a factor of five better than those made with pure silver. Many electric power devices require the wire to be formed into coils for production of strong magnetic fields. Requirements for coils and magnets for electric power applications are described.

Hawsey, Robert A.; Sokolowski, Robert S.; Haldar, Pradeep; Motowidlo, Leszek R.

1995-01-01

295

Cooling, Heating, Generating Power, and Recovering Waste Heat with Thermoelectric Systems  

Microsoft Academic Search

Thermoelectric materials are solid-state energy converters whose combination of thermal, electrical, and semiconducting properties allows them to be used to convert waste heat into electricity or electrical power directly into cooling and heating. These materials can be competitive with fluid-based systems, such as two-phase air-conditioning compressors or heat pumps, or used in smaller-scale applications such as in automobile seats, night-vision

Lon E. Bell

2008-01-01

296

Analysis to the Reliability of Evaporative Cooling Turbo generator in Power System  

Microsoft Academic Search

Evaporative cooling technique is successfully applied for large turbo generator following the air-cooled, hydrogen- cooled and water-cooled techniques. Compared with the three techniques, evaporative cooling technique absorbs the heat of thermal parts of generator by vaporization latent heat of coolant, which is sharply more efficient than the specific heat cooling approaches. The temperature rise of evaporative cooling generator can be

Bin Xiong; GuoBiao Gu

2011-01-01

297

Feasibility study of a cryogenically cooled window for high-power gyrotrons  

NASA Astrophysics Data System (ADS)

Single-crystal sapphire is currently in use as the material for output windows in high-power microwave tubes, particularly gyrotrons. These windows are currently being cooled by fluorocarbon fluids at near-room temperatures. There are, however, several advantages in operating the window at very low temperatures: less absorption and consequent heating of the window, greater material strength, improved resistance to crack formation, greater thermal conductivity, and reduced thermal expansion. Operation at cryogenic temperatures is shown to be feasible. The output power, which is currently limited by window constraints, could be increased by an order of magnitude or more.

Haste, G. R.; Kimrey, H. D.; Prosise, J. D.

1986-07-01

298

Cryogenic Technology for Superconducting Accelerators  

NASA Astrophysics Data System (ADS)

Superconducting devices such as magnets and cavities are key components in the accelerator field for increasing the beam energy and intensity, and at the same time making the system compact and saving on power consumption in operation. An effective cryogenic system is required to cool and keep the superconducting devices in the superconducting state stably and economically. The helium refrigeration system for application to accelerators will be discussed in this review article. The concept of two cooling modes -- the liquefier and refrigerator modes -- will be discussed in detail because of its importance for realizing efficient cooling and stable operation of the system. As an example of the practical cryogenic system, the TRISTAN cryogenic system of KEK Laboratory will be treated in detail and the main components of the cryogenic system, including the high-performance multichannel transfer line and liquid nitrogen circulation system at 80K, will also be discussed. In addition, we will discuss the operation of the cryogenic system, including the quench control and safety of the system. The satellite refrigeration system will be discussed because of its potential for wide application in medium-size accelerators and in industry.

Hosoyama, Kenji

2012-01-01

299

Injection locking of a high power ultraviolet laser diode for laser cooling of ytterbium atoms  

E-print Network

We developed a high-power laser system at a wavelength of 399 nm for laser cooling of ytterbium atoms with ultraviolet laser diodes. The system is composed of an external cavity laser diode providing frequency stabilized output at a power of 40 mW and another laser diode for amplifying the laser power up to 220 mW by injection locking. The systematic method for optimization of our injection locking can also be applied to high power light sources at any other wavelengths. Our system, which does not depend on complex nonlinear frequency-doubling, has great importance for implementing transportable optical lattice clocks, and is also useful for investigations on condensed matter physics or quantum information processing using cold atoms.

Toshiyuki Hosoya; Martin Miranda; Ryotaro Inoue; Mikio Kozuma

2014-12-02

300

Power flattening on modified CANDLE small long life gas-cooled fast reactor  

NASA Astrophysics Data System (ADS)

Gas-cooled Fast Reactor (GFR) is one of the candidates of next generation Nuclear Power Plants (NPPs) that expected to be operated commercially after 2030. In this research conceptual design study of long life 350 MWt GFR with natural uranium metallic fuel as fuel cycle input has been performed. Modified CANDLE burn-up strategy with first and second regions located near the last region (type B) has been applied. This reactor can be operated for 10 years without refuelling and fuel shuffling. Power peaking reduction is conducted by arranging the core radial direction into three regions with respectively uses fuel volume fraction 62.5%, 64% and 67.5%. The average power density in the modified core is about 82 Watt/cc and the power peaking factor decreased from 4.03 to 3.43.

Monado, Fiber; Su'ud, Zaki; Waris, Abdul; Basar, Khairul; Ariani, Menik; Sekimoto, Hiroshi

2014-09-01

301

Contingency power for small turboshaft engines using water injection into turbine cooling air  

NASA Technical Reports Server (NTRS)

Because of one engine inoperative requirements, together with hot-gas reingestion and hot day, high altitude takeoff situations, power augmentation for multiengine rotorcraft has always been of critical interest. However, power augmentation using overtemperature at the turbine inlet will shorten turbine life unless a method of limiting thermal and mechanical stresses is found. A possible solution involves allowing the turbine inlet temperature to rise to augment power while injecting water into the turbine cooling air to limit hot-section metal temperatures. An experimental water injection device was installed in an engine and successfully tested. Although concern for unprotected subcomponents in the engine hot section prevented demonstration of the technique's maximum potential, it was still possible to demonstrate increases in power while maintaining nearly constant turbine rotor blade temperature.

Biesiadny, Thomas J.; Klann, Gary A.; Clark, David A.; Berger, Brett

1987-01-01

302

Contingency power for a small turboshaft engine by using water injection into turbine cooling air  

NASA Technical Reports Server (NTRS)

Because of one-engine-inoperative (OEI) requirements, together with hot-gas reingestion and hot-day, high-altitude take-off situations, power augmentation for multiengine rotorcraft has always been of critical interest. However, power augmentation by using overtemperature at the turbine inlet will shorten turbine life unless a method of limiting thermal and mechanical stress is found. A possible solution involves allowing the turbine inlet temperature to rise to augment power while injecting water into the turbine cooling air to limit hot-section metal temperatures. An experimental water injection device was installed in an engine and successfully tested. Although concern for unprotected subcomponents in the engine hot section prevented demonstration of the technique's maximum potential, it was still possible to demonstrate increases in power while maintaining nearly constant turbine rotor blade temperature.

Biesiadny, Thomas J.; Klann, Gary A.

1992-01-01

303

Topographic power spectral density study of the effect of surface treatment processes on niobium for superconducting radio frequency accelerator cavities  

DOE PAGESBeta

Microroughness is viewed as a critical issue for attaining optimum performance of superconducting radio frequency accelerator cavities. The principal surface smoothing methods are buffered chemical polish (BCP) and electropolish (EP). The resulting topography is characterized by atomic force microscopy (AFM). The power spectral density (PSD) of AFM data provides a more thorough description of the topography than a single-value roughness measurement. In this work, one dimensional average PSD functions derived from topography of BCP and EP with different controlled starting conditions and durations have been fitted with a combination of power law, K correlation, and shifted Gaussian models to extract characteristic parameters at different spatial harmonic scales. While the simplest characterizations of these data are not new, the systematic tracking of scale-specific roughness as a function of processing is new and offers feedback for tighter process prescriptions more knowledgably targeted at beneficial niobium topography for superconducting radio frequency applications.

Xu, Chen; Tian, Hui; Reece, Charles E.; Kelley, Michael J.

2012-04-01

304

Multi-criteria decision analysis of concentrated solar power with thermal energy storage and dry cooling.  

PubMed

Decisions about energy backup and cooling options for parabolic trough (PT) concentrated solar power have technical, economic, and environmental implications. Although PT development has increased rapidly in recent years, energy policies do not address backup or cooling option requirements, and very few studies directly compare the diverse implications of these options. This is the first study to compare the annual capacity factor, levelized cost of energy (LCOE), water consumption, land use, and life cycle greenhouse gas (GHG) emissions of PT with different backup options (minimal backup (MB), thermal energy storage (TES), and fossil fuel backup (FF)) and different cooling options (wet (WC) and dry (DC). Multicriteria decision analysis was used with five preference scenarios to identify the highest-scoring energy backup-cooling combination for each preference scenario. MB-WC had the highest score in the Economic and Climate Change-Economy scenarios, while FF-DC and FF-WC had the highest scores in the Equal and Availability scenarios, respectively. TES-DC had the highest score for the Environmental scenario. DC was ranked 1-3 in all preference scenarios. Direct comparisons between GHG emissions and LCOE and between GHG emissions and land use suggest a preference for TES if backup is require for PT plants to compete with baseload generators. PMID:24245524

Klein, Sharon J W

2013-12-17

305

ENVIRONMENTAL PROBLEMS ASSOCIATED WITH DECOMMISSIONING THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND  

SciTech Connect

Decommissioning of nuclear power plants and other nuclear fuel cycle facilities has been an imperative issue lately. There exist significant experience and generally accepted recommendations on remediation of lands with residual radioactive contamination; however, there are hardly any such recommendations on remediation of cooling ponds that, in most cases, are fairly large water reservoirs. The literature only describes remediation of minor reservoirs containing radioactive silt (a complete closure followed by preservation) or small water reservoirs resulting in reestablishing natural water flows. Problems associated with remediation of river reservoirs resulting in flooding of vast agricultural areas also have been described. In addition, the severity of environmental and economic problems related to the remedial activities is shown to exceed any potential benefits of these activities. One of the large, highly contaminated water reservoirs that require either remediation or closure is Karachay Lake near the MAYAK Production Association in the Chelyabinsk Region of Russia where liquid radioactive waste had been deep well injected for a long period of time. Backfilling of Karachay Lake is currently in progress. It should be noted that secondary environmental problems associated with its closure are considered to be of less importance since sustaining Karachay Lake would have presented a much higher radiological risk. Another well-known highly contaminated water reservoir is the Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond, decommissioning of which is planned for the near future. This study summarizes the environmental problems associated with the ChNPP Cooling Pond decommissioning.

Farfan, E.

2009-09-30

306

Environmental Problems Associated With Decommissioning The Chernobyl Nuclear Power Plant Cooling Pond  

SciTech Connect

Decommissioning of nuclear power plants and other nuclear fuel cycle facilities has been an imperative issue lately. There exist significant experience and generally accepted recommendations on remediation of lands with residual radioactive contamination; however, there are hardly any such recommendations on remediation of cooling ponds that, in most cases, are fairly large water reservoirs. The literature only describes remediation of minor reservoirs containing radioactive silt (a complete closure followed by preservation) or small water reservoirs resulting in reestablishing natural water flows. Problems associated with remediation of river reservoirs resulting in flooding of vast agricultural areas also have been described. In addition, the severity of environmental and economic problems related to the remedial activities is shown to exceed any potential benefits of these activities. One of the large, highly contaminated water reservoirs that require either remediation or closure is Karachay Lake near the MAYAK Production Association in the Chelyabinsk Region of Russia where liquid radioactive waste had been deep well injected for a long period of time. Backfilling of Karachay Lake is currently in progress. It should be noted that secondary environmental problems associated with its closure are considered to be of less importance since sustaining Karachay Lake would have presented a much higher radiological risk. Another well-known highly contaminated water reservoir is the Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond, decommissioning of which is planned for the near future. This study summarizes the environmental problems associated with the ChNPP Cooling Pond decommissioning.

Farfan, E. B.; Jannik, G. T.; Marra, J. C.; Oskolkov, B. Ya.; Bondarkov, M. D.; Gaschak, S. P.; Maksymenko, A. M.; Maksymenko, V. M.; Martynenko, V. I.

2009-11-09

307

Effect of makeup water properties on the condenser fouling in power planr cooling system  

SciTech Connect

The thermoelectric power industry in the U.S. uses a large amount of fresh water. As available freshwater for use in thermoelectric power production becomes increasingly limited, use of nontraditional water sources is of growing interest. Utilization of nontraditional water, in cooling systems increases the potential for mineral precipitation on heat exchanger surfaces. In that regard, predicting the accelerated rate of scaling and fouling in condenser is crucial to evaluate the condenser performance. To achieve this goal, water chemistry should be incorporated in cooling system modeling and simulation. This paper addresses the effects of various makeup water properties on the cooling system, namely pH and aqueous speciation, both of which are important factors affecting the fouling rate in the main condenser. Detailed modeling of the volatile species desorption (i.e. CO{sub 2} and NH{sub 3}), the formation of scale in the recirculating system, and the relationship between water quality and the corresponding fouling rates is presented.

Safari, I.; Walker, M.; Abbasian, J.; Arastoopour, H.; Hsieh, M-K.; Dzombak, D.; Miller, D.

2011-01-01

308

Design of 154 kV Extra-High-Voltage Prototype SF6 Bushing for Superconducting Electric Power Applications  

NASA Astrophysics Data System (ADS)

One of the critical components to be developed for high-voltage superconducting devices, such as superconducting transformers, cables, and fault current limiters, is a high-voltage bushing to supply a high current to devices without insulation difficulties in cryogenic environments. Unfortunately, suitable bushings for high-temperature-superconductivity (HTS) equipment have not been fully developed to address cryogenic insulation issues. As a fundamental step towards developing the optimum design of the 154 kV prototype SF6 bushing of HTS devices, the puncture and creepage breakdown voltages of glass-fiber-reinforced-plastic (GFRP) were analyzed with a variety of configurations of electrodes and gap distances in the insulation material. And design factors of high-voltage cryogenic bushings were obtained from the result of tests. Finally, the withstand voltage tests of manufacturing a 154 kV extra-high-voltage (EHV) prototype bushing has been performed. Consequently, we verified the insulation level of the newly designed 154 kV EHV cryogenic prototype bushings for superconducting electric power applications.

Koo, Ja-yoon; Seong, Jae-gyu; Hwang, Jae-sang; Lee, Bang-wook; Lee, Sang-hwa

2012-09-01

309

AP1000{sup R} nuclear power plant safety overview for spent fuel cooling  

SciTech Connect

The AP1000{sup R} plant is an 1100-MWe class pressurized water reactor with passive safety features and extensive plant simplifications that enhance construction, operation, maintenance, safety and costs. The AP1000 design uses passive features to mitigate design basis accidents. The passive safety systems are designed to function without safety-grade support systems such as AC power, component cooling water, service water or HVAC. Furthermore, these passive features 'fail safe' during a non-LOCA event such that DC power and instrumentation are not required. The AP1000 also has simple, active, defense-in-depth systems to support normal plant operations. These active systems provide the first level of defense against more probable events and they provide investment protection, reduce the demands on the passive features and support the probabilistic risk assessment. The AP1000 passive safety approach allows the plant to achieve and maintain safe shutdown in case of an accident for 72 hours without operator action, meeting the expectations provided in the U.S. Utility Requirement Document and the European Utility Requirements for passive plants. Limited operator actions are required to maintain safe conditions in the spent fuel pool via passive means. In line with the AP1000 approach to safety described above, the AP1000 plant design features multiple, diverse lines of defense to ensure spent fuel cooling can be maintained for design-basis events and beyond design-basis accidents. During normal and abnormal conditions, defense-in-depth and other systems provide highly reliable spent fuel pool cooling. They rely on off-site AC power or the on-site standby diesel generators. For unlikely design basis events with an extended loss of AC power (i.e., station blackout) or loss of heat sink or both, spent fuel cooling can still be provided indefinitely: - Passive systems, requiring minimal or no operator actions, are sufficient for at least 72 hours under all possible pool heat load conditions. - After 3 days, several different means are provided to continue spent fuel cooling using installed plant equipment as well as off-site equipment with built-in connections. Even for beyond design basis accidents with postulated pool damage and multiple failures in the passive safety-related systems and in the defense-in-depth active systems, the AP1000 multiple spent fuel pool spray and fill systems provide additional lines of defense to prevent spent fuel damage. (authors)

Gorgemans, J.; Mulhollem, L.; Glavin, J.; Pfister, A.; Conway, L.; Schulz, T.; Oriani, L.; Cummins, E.; Winters, J. [Westinghouse Electric Company LLC, 1000 Westinghouse Drive, Cranberry Township, PA 16066 (United States)

2012-07-01

310

An approach for electrical self-stabilization of high-temperature superconducting wires for power applications  

NASA Astrophysics Data System (ADS)

Electrical and thermal stability of high-temperature superconducting (HTS) wires/tapes are essential in applications involving efficient production, distribution, and storage of electrical energy. We have developed a conductive buffer layer structure composed of bilayer La0.7Sr0.3MnO3/Ir on a textured Ni -W alloy metal tape to functionally shunt the HTS layer to the underlying substrate. The key feature is the Ir layer, which serves as a barrier to both inward diffusion of oxygen and outward diffusion of metal substrate cations during fabrication. Electrical and microstructural property characterizations of YBa2Cu3O7-? films on short prototype conductors demonstrate self-field critical current density values, Jc, exceeding 2×106A /cm2 at 77K and excellent electrical coupling to the underlying metal substrate, with no unwanted insulating oxide interfaces. Implementing this approach in power technologies would significantly increase the engineering current density of the conductor and reduce overall process costs.

Aytug, T.; Paranthaman, M.; Zhai, H. Y.; Gapud, A. A.; Leonard, K. J.; Martin, P. M.; Goyal, A.; Thompson, J. R.; Christen, D. K.

2004-10-01

311

Heterogeneous Superconducting Low-Noise Sensing Coils  

NASA Technical Reports Server (NTRS)

A heterogeneous material construction has been devised for sensing coils of superconducting quantum interference device (SQUID) magnetometers that are subject to a combination of requirements peculiar to some advanced applications, notably including low-field magnetic resonance imaging for medical diagnosis. The requirements in question are the following: The sensing coils must be large enough (in some cases having dimensions of as much as tens of centimeters) to afford adequate sensitivity; The sensing coils must be made electrically superconductive to eliminate Johnson noise (thermally induced noise proportional to electrical resistance); and Although the sensing coils must be cooled to below their superconducting- transition temperatures with sufficient cooling power to overcome moderate ambient radiative heat leakage, they must not be immersed in cryogenic liquid baths. For a given superconducting sensing coil, this combination of requirements can be satisfied by providing a sufficiently thermally conductive link between the coil and a cold source. However, the superconducting coil material is not suitable as such a link because electrically superconductive materials are typically poor thermal conductors. The heterogeneous material construction makes it possible to solve both the electrical- and thermal-conductivity problems. The basic idea is to construct the coil as a skeleton made of a highly thermally conductive material (typically, annealed copper), then coat the skeleton with an electrically superconductive alloy (typically, a lead-tin solder) [see figure]. In operation, the copper skeleton provides the required thermally conductive connection to the cold source, while the electrically superconductive coating material shields against Johnson noise that originates in the copper skeleton.

Hahn, Inseob; Penanen, Konstantin I.; Ho Eom, Byeong

2008-01-01

312

Environmental Problems Associated with Decommissioning of Chernobyl Power Plant Cooling Pond  

NASA Astrophysics Data System (ADS)

Decommissioning of nuclear power plants and other nuclear fuel cycle facilities associated with residual radioactive contamination is a fairly pressing issue. Significant problems may result from decommissioning of cooling ponds. The Chernobyl Nuclear Power Plant (ChNPP) Cooling Pond is one of the largest self-contained bodies of water in the Chernobyl Region and Ukrainian Polesye with a water surface area of 22.9 km2. The major hydrological feature of the ChNPP Cooling Pond is that its water level is 6-7 m higher than the water level in the Pripyat River and water losses due to seepage and evaporation are replenished by pumping water from the Pripyat River. In 1986, the accident at the ChNPP #4 Reactor Unit significantly contaminated the ChNPP Cooling Pond. According to the 2001 data, the total radionuclide inventory in the ChNPP Cooling Pond bottom deposits was as follows: 16.28 ± 2.59 TBq for 137Cs; 2.4 ± 0.48 TBq for 90Sr, and 0.00518 ± 0.00148 TBq for 239+240Pu. Since ChNPP is being decommissioned, the ChNPP Cooling Pond of such a large size will no longer be needed and cost effective to maintain. However, shutdown of the water feed to the Pond would expose the contaminated bottom deposits and change the hydrological features of the area, destabilizing the radiological and environmental situation in the entire region in 2007 - 2008, in order to assess potential consequences of draining the ChNPP Cooling Pond, the authors conducted preliminary radio-ecological studies of its shoreline ecosystems. The radioactive contamination of the ChNPP Cooling Pond shoreline is fairly variable and ranges from 75 to 7,500 kBq/m2. Three areas with different contamination levels were selected to sample soils, vegetation, small mammals, birds, amphibians, and reptilians in order to measure their 137Cs and 90Sr content. Using the ERICA software, their dose exposures were estimated. For the 2008 conditions, the estimated dose rates were found to be as follows: amphibians - 11.4 µGy/hr; birds - 6.3 µGy/hr; mammals - 15.1 µGy/hr; reptilians - 10.3 µGy/hr, with the recommended maximum allowable limit of 40 µGy/hr. The conservative risk coefficient ranged from 0.51 for birds to 1.82 for amphibians. In spite of a high contamination level of the shoreline areas, the current total doses received by the animals do not reach the recommended maximum allowable doses. However, drainage of the ChNPP Cooling Pond is likely to increase the dose rates as follows: amphibians - 94.5, birds - 95.2, mammals - 284.0, reptilians - 847.0 µGy/hr, which will significantly exceed the maximum allowable values. These predictions are conservative and prior to making the final decision on the fate of the ChNPP Cooling Pond, a detailed radio-ecological assessment of its drainage will have to be performed.

Foley, T. Q.; Oskolkov, B. Y.; Bondarkov, M. D.; Gashchak, S. P.; Maksymenko, A. M.; Maksymenko, V. M.; Martynenko, V. I.; Jannik, G. T.; Farfan, E. B.; Marra, J. C.

2009-12-01

313

Breeding blanket design and systems integration for a helium-cooled lithium–lead fusion power plant  

Microsoft Academic Search

This paper describes the work performed for the power plant conceptual studies (PPCS) reactor model AB, a ‘near-term’ fusion power reactor based on limited extrapolations from today knowledge on technology and plasma physic assumption, featuring a helium-cooled lithium lead (HCLL) blanket concept and a He cooled divertor.The main design rational and characteristics of the PPCS model AB as well as

A. Li Puma; J. L. Berton; B. Brañas; L. Bühler; J. Doncel; U. Fischer; W. Farabolini; L. Giancarli; D. Maisonnier; P. Pereslavtsev; S. Raboin; J.-F. Salavy; P. Sardain; J. Szczepanski; D. Ward

2006-01-01

314

Cooling, heating, generating power, and recovering waste heat with thermoelectric systems.  

PubMed

Thermoelectric materials are solid-state energy converters whose combination of thermal, electrical, and semiconducting properties allows them to be used to convert waste heat into electricity or electrical power directly into cooling and heating. These materials can be competitive with fluid-based systems, such as two-phase air-conditioning compressors or heat pumps, or used in smaller-scale applications such as in automobile seats, night-vision systems, and electrical-enclosure cooling. More widespread use of thermoelectrics requires not only improving the intrinsic energy-conversion efficiency of the materials but also implementing recent advancements in system architecture. These principles are illustrated with several proven and potential applications of thermoelectrics. PMID:18787160

Bell, Lon E

2008-09-12

315

Efficiency and its bounds for thermal engines at maximum power using Newton's law of cooling.  

PubMed

We study a thermal engine model for which Newton's cooling law is obeyed during heat transfer processes. The thermal efficiency and its bounds at maximum output power are derived and discussed. This model, though quite simple, can be applied not only to Carnot engines but also to four other types of engines. For the long thermal contact time limit, new bounds, tighter than what were known before, are obtained. In this case, this model can simulate Otto, Joule-Brayton, Diesel, and Atkinson engines. While in the short contact time limit, which corresponds to the Carnot cycle, the same efficiency bounds as that from Esposito et al. [Phys. Rev. Lett. 105, 150603 (2010)] are derived. In both cases, the thermal efficiency decreases as the ratio between the heat capacities of the working medium during heating and cooling stages increases. This might provide instructions for designing real engines. PMID:22400551

Yan, H; Guo, Hao

2012-01-01

316

Medium factors of electrical insulation systems in high temperature superconducting power apparatus with coil structure for equivalent ac withstand voltage test at room temperature  

Microsoft Academic Search

Equivalent insulation test voltage at room temperature of high temperature superconducting (HTS) power apparatus with coil structure for power frequency withstand voltage tests is discussed based on medium factors of insulation weak parts in electrical insulation elements of the HTS power apparatus. Uniform and non-uniform field gaps, triple junction and solid insulator surface are selected as the insulation weak parts,

M. Hara; T. Kurihara; R. Nakano; J. Suehiro

2005-01-01

317

High-power laser phosphor light source with liquid cooling for digital cinema applications  

NASA Astrophysics Data System (ADS)

Laser excited phosphor has been used to excite phosphor material, producing high intensity light output with smaller etendue than that of LEDs with the same long lifetime. But due to the high intensity of the laser light, phosphor with organic binder burns at low power, which requires the phosphor to be deposited on a rotating wheel in practical applications. Phosphor with inorganic binders, commonly known as ceramic phosphor, on the other hand, does not burn, but efficiency goes down as temperature goes up under high power excitation. This paper describes cooling schemes in sealed chambers such that the phosphor materials using organic or inorganic binders can be liquid cooled for high efficiency operations. Confined air bubbles are introduced into the sealed chamber accommodating the differential thermal expansion of the liquid and the chamber. For even higher power operation suitable for digital cinema, a suspension of phosphor in liquid is described suitable for screen brightness of over 30,000 lumens. The aging issues of phosphor can also be solved by using replaceable phosphor cartridges.

Li, Kenneth

2014-02-01

318

High-Powered Gas-Cooled Microwave Ablation: Shaft Cooling Creates an Effective Stick Function Without Altering the Ablation Zone  

PubMed Central

OBJECTIVE The purpose of our study was to validate the ability of a new gas-cooled microwave device to secure antennas into tissue before ablation via shaft cooling and to verify that such cooling does not compromise the intended ablation. MATERIALS AND METHODS The force required to extract several types of applicators from ex vivo bovine liver before and after ablation was measured. Six groups were compared: cooled needle and multitined radiofrequency electrodes, secured and unsecured cryoprobes, and gas-cooled microwave antennas (n = 6 each). Ablations were next created in in vivo porcine livers for 2 and 10 minutes (n = 6 each) using the gas-cooled microwave system at 140 W. Extraction force was again measured before and after ablation and compared between groups using analysis of variance with post hoc Student t tests. Histologic analysis of the ablation zone was performed to evaluate cellular necrosis along the antenna shaft. RESULTS Ex vivo, the secured cryoprobe and microwave antenna required significantly more force to remove than unsecured radiofrequency, cryoprobe, and microwave applicators (p < 0.05, all comparisons). The multitined radiofrequency electrode and cooled radiofrequency electrode required significantly more force to remove after ablation than before ablation (p = 0.006 and 0.02, respectively). In vivo, the secured antenna required significantly more force to remove before ablation than after ablation at both 2 (p < 0.0001) and 10 minutes (p < 0.0001). There was no histologic evidence of cell preservation along the antenna shaft. CONCLUSION The gas cooling used in this microwave device can effectively secure antennas into tissue without altering ablation shape or reducing the intended thermal damage. PMID:22358023

Knavel, Erica M.; Hinshaw, J. Louis; Lubner, Meghan G.; Andreano, Anita; Warner, Thomas F.; Lee, Fred T.; Brace, Christopher L.

2012-01-01

319

Rotating cryostats for heat transfer and fluid flow studies on the helium cooling of superconducting generator rotors  

NASA Astrophysics Data System (ADS)

This paper describes the design and construction of two 1 m diameter rotating cryostats for the study of the heat transfer and fluid flow behaviour of helium at 3000 r.p.m. towards the design of refrigeration systems for superconducting a.c. generators. The first LO rotating cryostat has been in continual operation since 1976 and a great deal of basic data has been produced on the high convective heat transfer performance of helium, on the self-pumping capability of helium gas loops and their associated intrinsic instability, on the behaviour of superfluid helium and the He I/He II interface, and on the forward and reverse flows in thermo-siphon loops, together with a wide range of practical experience with rotating helium and instrumentation at 3000 r.p.m., 5000 g or 150 ms -1 tip speed. A second LX rotating cryostat with increased working volume is also described.

Haseler, L. E.; Lorch, H. O.; Rao, M. G.; Scurlock, R. G.; Stevens, F. A.; Utton, D. B.

320

State of the art of superconducting fault current limiters and their application to the electric power system  

NASA Astrophysics Data System (ADS)

Modern electric power systems are becoming more and more complex in order to meet new needs. Nowadays a high power quality is mandatory and there is the need to integrate increasing amounts of on-site generation. All this translates in more sophisticated electric network with intrinsically high short circuit rate. This network is vulnerable in case of fault and special protection apparatus and procedures needs to be developed in order to avoid costly or even irreversible damage. A superconducting fault current limiter (SFCL) is a device with a negligible impedance in normal operating conditions that reliably switches to a high impedance state in case of extra-current. Such a device is able to increase the short circuit power of an electric network and to contemporarily eliminate the hazard during the fault. It can be regarded as a key component for future electric power systems. In this paper the state of the art of superconducting fault current limiters mature for applications is briefly resumed and the potential impact of this device on the paradigm of design and operation of power systems is analyzed. In particular the use of the FCL as a mean to allow more interconnection of MV bus-bars as well an increased immunity with respect to the voltage disturbances induced by critical customer is discussed. The possibility to integrate more distributed generation in the distribution grid is also considered.

Morandi, Antonio

2013-01-01

321

Harvest of Blue tilapia (Tilapia aurea) from a power plant cooling lake  

E-print Network

May 1986 Major Subject: Wildlife and Fisheries Sciences HARVEST OF BLUE TILAPIA (TILAPIA AUREA) FROM A POWER PLANT COOLING LAKE A Thesis by ROBERT ANDREW MECUM Approved as to style and content by: Kirk Strawn (Chair of Committee) Rudol J... are cultured throughout the tropics and sub- tropics and, with the probabl e exception of the common carp, are the most widely cultured fish in the world (Bardach et a 1. 1972). Ti l~aia aurea (Steindachner), a mouthbrooder of the family Cichlidae...

Mecum, Robert Andrew

1986-01-01

322

Determining Optimal Equipment Capacities in Cooling, Heating and Power (CHP) Systems  

SciTech Connect

Evaluation of potential cooling, heating and power (CHP) applications requires an assessment of the operations and economics of a particular system in meeting the electric and thermal demands of a specific end-use facility. A key determinate in whether a candidate system will be economic is the proper selection of equipment capacities. A methodology to determine the optimal capacities for CHP prime movers and absorption chillers using nonlinear optimization algorithms has been coded into a Microsoft Excel spreadsheet tool that performs the capacity optimization and operations simulation. This paper presents details on the use and results of this publicly available tool.

DeVault, Robert C [ORNL; Hudson II, Carl Randy [ORNL

2006-01-01

323

Compatibility tests of materials for a lithium-cooled space power reactor concept  

NASA Technical Reports Server (NTRS)

Materials for a lithium-cooled space power reactor concept must be chemically compatible for up to 50,000 hr at high temperature. Capsule tests at 1040 C (1900 F) were made of material combinations of prime interest: T-111 in direct contact with uranium mononitride (UN), Un in vacuum separated from T-111 by tungsten wire, UN with various oxygen impurity levels enclosed in tungsten wire lithium-filled T-111 capsules, and TZM and lithium together in T-111 capsules. All combinations were compatible for over 2800 hr except for T-111 in direct contact with UN.

Sinclair, J. H.

1973-01-01

324

Analysis of Unsymmetrical Faults in High Voltage Power Systems With Superconducting Fault Current Limiters  

Microsoft Academic Search

An analysis of unsymmetrical faults for a 110 kV sub-grid coupling with a superconducting fault current limiter is conducted in this contribution. For the design of the super-conducting fault current limiters it is essential to identify the highest possible voltage during the limitation process. As reference the symmetric three phase fault which generally leads to the highest short-circuit currents is

Mark Stemmle; Claus Neumann; Frank Merschel; Ulrich Schwing; Karl-Heinz Weck; Mathias Noe; Frank Breuer; Steffen Elschner

2007-01-01

325

Outbreak of legionnaires' disease from a cooling water system in a power station.  

PubMed Central

In September and October 1981 six cases of pneumonia occurred among men working in a power station under construction. Three were identified as cases of legionella pneumonia and two others had serology suggestive of legionella infection. In a sample of 92 men from the site 10 had low levels of antibodies to legionella; a similar sample of men working on an adjacent site showed none with positive serology. In a case control study it was found that cases of pneumonia were more likely than controls to have worked on a part of the site where four small capacity cooling towers were located. Legionella pneumophila serogroup 1 was isolated from the water systems of these four towers but was not found in samples from any other cooling towers or hot or cold water outlets on the site. It would appear that there was airborne spread of the organism from these cooling water systems which had not received conventional treatment to inhibit corrosion and organic growth. This is the first outbreak of legionnaires' disease to be recorded in an industrial setting in the United Kingdom. No cases of legionella infection have occurred on the site since the introduction of control measures. PMID:3756116

Morton, S; Bartlett, C L; Bibby, L F; Hutchinson, D N; Dyer, J V; Dennis, P J

1986-01-01

326

Analysis of the solar powered/fuel assisted Rankine cycle cooling system. Phase 1: Revision  

NASA Astrophysics Data System (ADS)

The subject of this analysis is a solar cooling system which consists of a conventional open-compressor chiller, driven by a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100C, and it is then superheated to about 600C in a fossil-fuel fired superheater. The steam drives a novel counter-rotating turbine, some of the heat from it is regenerated, and it is then condensed. Thermal storage is implemented as an integral part of the cycle, by means of hot-water which is flashed to steam when needed for driving the turbine. For the solar energy input, both evacuated and double-glazed flat-plate collectors were considered. A comprehensive computer program was developed to analyze the operation and performance of the entire power/cooling system. Each component was described by a separate subroutine to compute its performance from basic principles, and special attention was given to the parasitic losses, including pumps, fans and pressure drops in the piping and heat exchangers, and to describe the off-design performance of the components. The thermophysical properties of the fluids used are also described in separate subroutines. Transient simulation of the entire system was performed on an hourly basis over a cooling season in two representative climatic regions (Washington, DC, and Phoenix, AZ) for a number of system configurations.

Lior, N.; Koai, K.; Yeh, H.

1985-04-01

327

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 Energy’s 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 team’s 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 wetland’s 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

328

Superconducting magnet for nuclei orientation  

E-print Network

. Introduction . . . . . ~ ~ ~ ~ ~ ~ ~ ~ II. Superconducting Magnet 1 ~ Superconductivity and Super- conliuc'tore ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 3 2. Superconducting Solenoid Model 1 ~ ~ o ~ e ~ o ~ ~ ~ ~ ~ ~ eoe ~ ~ o ~ oeo 1Q Superconducting... drops suddenly to zero when the specimen is cooled down to a sufficiently: low temperature. Another dramat1c property exhibited by a super- conductor is a magnetic property. It 1s an experi- mental fact that when a bulk specimen is placed in a weak...

Wang, Fa-Chung

1968-01-01

329

Superconducting mirror for laser gyroscope  

SciTech Connect

This paper describes an apparatus for reflecting a light beam. It comprises: a mirror assembly comprising a substrate and a superconductive mirror formed on such substrate, wherein: the substrate is optically transparent to the light beam and has a thickness of from about 0.5 to about 1.0 millimeter, and the superconductive mirror has a thickness of from about 0.5 to about 1.0 microns; means for cooling the superconductive mirror; means for measuring the temperature of the superconductive mirror; means for determining the reflectivity of the superconductive mirror; and means for varying the reflectivity of the superconductive mirror.

Wang, X.

1991-05-14

330

Design and test of a simplified and reliable cryogenic system for high speed superconducting generator applications  

NASA Astrophysics Data System (ADS)

Under the contract with Air Force Research Lab (AFRL), General Electric has successfully tested a high speed, superconducting generator for a Multimegawatt Electric Power System (MEPS). As the first successful full-power test of a superconducting generator for the Air Force, the demonstration tested the generator's load up to 1.3 MW and over 10,000 rpm. A key component of the generator system is a closed loop cryo-refrigeration system to cool the field excitation coil at liquid neon temperature. This paper reports the design and tests of the cryogenic system, including the liquid neon dewar, cryogenic cooling loop for the high temperature superconducting (HTS) field coil and the cryostat. Performance data during both short-term load run and long-term non-load run were presented. Also, some key issues to design a reliable cryogenic system for a superconducting generator were discussed.

Zhang, T.; Haran, K.; Laskaris, E. T.; Bray, J. W.

2011-07-01

331

Powering of cool filaments in cluster cores by buoyant bubbles - I. Qualitative model  

NASA Astrophysics Data System (ADS)

Cool-core clusters (e.g. Perseus or M87) often possess a network of bright gaseous filaments, observed in radio, infrared, optical and X-ray bands. We propose that these filaments are powered by the reconnection of the magnetic field in the wakes of buoyant bubbles. Active galactic nucleus (AGN)-inflated bubbles of relativistic plasma rise buoyantly in the cluster atmosphere, stretching and amplifying the field in the wake to values of ? = 8?Pgas/B2 ˜ 1. The field lines in the wake have opposite directions and are forced together as the bubble motion stretches the filament. This setup bears strong similarity to the coronal loops on the Sun or to the Earth's magnetotail. The reconnection process naturally explains both the required level of local dissipation rate in filaments and the overall luminosity of filaments. The original source of power for the filaments is the potential energy of buoyant bubbles, inflated by the central AGN.

Churazov, E.; Ruszkowski, M.; Schekochihin, A.

2013-11-01

332

Design and testing of a phototype water-cooled vacuum interrupter for use in superconducting magnet protection circuits  

SciTech Connect

A water-cooled vacuum interrupter was designed and tested for use at 25 kA and 10 kV. This device is expected to have a lifetime approximately one order of magnitude greater than commercial dc circuit breakers. Testing showed that, although the device could successfully carry and interrupt 25 kA, interruption reliabililty was only about 95% with a 10 kV recovery voltage. In addition, a structural crack developed in one electrode from either thermal or mechanical stresses or a combination thereof. 11 refs., 4 figs., 1 tab.

Parsons, W.M.

1988-01-01

333

Numerical Hydraulic Study on Seawater Cooling System of Combined Cycle Power Plant  

NASA Astrophysics Data System (ADS)

As the rated flow and pressure increase in pumping facilities, a proper design against surges and severe cavitations in the pipeline system is required. Pressure surge due to start-up, shut-down process and operation failure causes the water hammer in upstream of the closing valve and the cavitational hammer in downstream of the valve. Typical cause of water hammer is the urgent closure of valves by breakdown of power supply and unexpected failure of pumps. The abrupt changes in the flow rate of the liquid results in high pressure surges in upstream of the valves, thus kinetic energy is transformed into potential energy which leads to the sudden increase of the pressure that is called as water hammer. Also, by the inertia, the liquid continues to flow downstream of the valve with initial speed. Accordingly, the pressure decreases and an expanding vapor bubble known as column separation are formed near the valve. In this research, the hydraulic study on the closed cooling water heat exchanger line, which is the one part of the power plant, is introduced. The whole power plant consists of 1,200 MW combined power plant and 220,000 m3/day desalination facility. Cooling water for the plant is supplied by sea water circulating system with a capacity of 29 m3/s. The primary focus is to verify the steady state hydraulic capacity of the system. The secondary is to quantify transient issues and solutions in the system. The circuit was modeled using a commercial software. The stable piping network was designed through the hydraulic studies using the simulation for the various scenarios.

Kim, J. Y.; Park, S. M.; Kim, J. H.; Kim, S. W.

2010-06-01

334

Micro capillary pumped loop system for a cooling high power device  

SciTech Connect

This work discusses the operation of a capillary-driven two-phase loop, configured on a micro capillary pumped loop (MCPL) system without an external power supply but capable of automatic heat transmission. The MCPL device, fabricated using MEMS (microelectricomechanical system) technology, was tested and yielded the following results: first, the proposed design of a new MCPL system with a water reservoir operating at low pressures is feasible and requires no additional power supply and instead relies on automatic heat transmission. Second, the issue of depriming in a MCPL was effectively controlled, the endurance of MCPL for the depriming problem can be executed by yielding input heat fluxes of 185.2 W/cm{sup 2} at an evaporator temperature of 165 C, thus revealing that this model provides excellent cooling performance. Third, the effective operation range was determined and its successful operation was confirmed for MCPL. The ease of starting up increased with the temperature of the reservoir. Finally, two-phase tension that originated in the groove structures in the evaporator and condenser was confirmed to control the movement of the fluids throughout the system and verified to be effective in improving cooling efficiency. (author)

Wang, Chin-Tsan [Department of Mechanical and Electro-Mechanical Engineering, National I-Lan University, 1, Sec. 1, Shen-Lung Road, I-Lan 26047 (China); Leu, Tzong-Shyng; Lai, Tsai-Ming [Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan 701 (China)

2008-04-15

335

Optimizing Cooling Tower Performance Refrigeration Systems, Chemical Plants, and Power Plants All Have A Resource Quietly Awaiting Exploitation-Cold Water!!  

E-print Network

Cooling towers, because of their seeming simplicity, are usually orphans of the facilities operation. We are all aware that cooling towers are the step-children of the chemical process plant, electric power generating station, and refrigeration...

Burger, R.

336

Transport critical current measurement apparatus using liquid nitrogen cooled high-Tc superconducting magnet with variable temperature insert  

NASA Astrophysics Data System (ADS)

We have developed an apparatus to investigate transport critical current (Ic) as a function of magnetic field and temperature using only liquid nitrogen. The apparatus consists of a (Bi,Pb)2Sr2Ca2Cu3O10 (Bi-2223) superconducting magnet, an outer dewar, and a variable temperature insert (VTI). The magnet, which is operated in depressurized liquid nitrogen, generates magnetic field up to 1.26 T. The sample is also immersed in liquid nitrogen. The pressure in the VTI is controlled from 0.02 to 0.3 MPa, which corresponds to temperature ranging from 66 to 88 K. We have confirmed the long-term stable operation of the Bi-2223 magnet at 1 T. The temperature stability of the sample at high transport current was also demonstrated. The apparatus provides easy-operating Ic measurement environment for a high-Tc superconductor up to 500 A in magnetic fields up to 1 T and in temperatures ranging from 66 to 88 K.

Nishijima, G.; Kitaguchi, H.; Tshuchiya, Y.; Nishimura, T.; Kato, T.

2013-01-01

337

A passive bearing system using superconducting magnets  

NASA Technical Reports Server (NTRS)

A passive radial bearing concept is presented using superconducting magnets which can generate a bearing pressure as high as 360 N/sq cm, comparable to a conventional active bearing system. The system consists of a number of solenoidal superconducting coils of alternating current direction. These coils are stacked axially over the bearing length and connected in series. The currents in stator and rotor coils are in the opposite directions, generating repulsive forces. This system, in comparison with an active system, has the advantage of much smaller power dissipation in the coils since the coil currents are mostly dc currents. The cooling for the superconducting coils is therefore simpler, and the coils are more stable. An optimization study seeking the maximum bearing pressure was conducted. Details of the design, pressure calculations, and results are presented.

Huang, X.; Eyssa, Y. M.

1990-01-01

338

A Closed Neon Liquefier System for Testing Superconducting Devices  

NASA Astrophysics Data System (ADS)

A Neon liquefier system has been developed by Southampton University (UK) and EDISON (Italy) with the aim to provide a facility for testing HTS superconducting devices using Magnesium Diboride materials, in the range 25-30K. The system consists of a liquid Neon cryostat coupled to a two stages cryocooler and a recovery system. The first stage of the cryocooler is connected to the thermal shield of the cryostat and a copper station positioned at mid point along the access neck to the liquid Neon bath to reduce heat leak and to provide pre-cooling of samples. The second stage, capable of 20W cooling power at 22K, is used to provide the cooling power for liquefaction and to refrigerate the liquid Neon bath and the superconducting device/sample during the steady state operation. The recovery system has been designed to automatically compress excess boil-off generated by a quench or a transient heating into a storage gas container. Transport measurement up to 900A can be carried out in the Ne cryostat using purposely build hybrid current leads. These leads have a copper upper section cooled by liquid Nitrogen and a superconducting lower section of Ag/AuBi2223 tapes. In this paper we report on the performance of the system and the initial measurement of superconducting samples.

Bianchetti, M.; Al-Mosawi, M. K.; Yang, Y.; Beduz, C.; Giunchi, G.

2006-04-01

339

User's guide for the BNW-III optimization code for modular dry/wet-cooled power plants  

SciTech Connect

This user's guide describes BNW-III, a computer code developed by the Pacific Northwest Laboratory (PNL) as part of the Dry Cooling Enhancement Program sponsored by the US Department of Energy (DOE). The BNW-III code models a modular dry/wet cooling system for a nuclear or fossil fuel power plant. The purpose of this guide is to give the code user a brief description of what the BNW-III code is and how to use it. It describes the cooling system being modeled and the various models used. A detailed description of code input and code output is also included. The BNW-III code was developed to analyze a specific cooling system layout. However, there is a large degree of freedom in the type of cooling modules that can be selected and in the performance of those modules. The costs of the modules are input to the code, giving the user a great deal of flexibility.

Braun, D.J.; Faletti, D.W.

1984-09-01

340

Oak Ridge National Laboratory (ORNL) Superconducting Technology Program for electric power systems. Annual report for FY 1994  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) Superconducting Technology Program is conducted as part of a national effort by the US Department of Energy`s Office of Energy Efficiency and Renewable Energy to develop the technology base needed by US industry for commercial development of electric power applications of high-temperature superconductivity. The three major elements of this program are conductor development, applications development, and the Superconductivity Partnership Initiative. This document describes the major research and development activities for this program together with related accomplishments. The technical progress reported was summarized from information prepared for the FY 1994 Annual Program Review held July 19--20, 2994. This ORNL program is highly leveraged by the staff and other resources of US industry and universities. In fact, nearly three-fourths of the ORNL effort is devoted to industrial competitiveness projects with private companies. Interlaboratory teams are also in place on a number of industry-driven projects. Patent disclosures, working group meetings, staff exchanges, and joint publications and presentations ensure that there is technology transfer with US industry. Working together, the collaborative teams are making rapid progress in solving the scientific and technical issues necessary for the commercialization of long lengths of practical high-temperature superconductor wire and wire products.

Koncinski, W.S. [ed.; Hawsey, R.A. [comp.

1994-12-01

341

Next generation cooled long range thermal sights with minimum size, weight, and power  

NASA Astrophysics Data System (ADS)

Situational awareness and precise targeting at day, night and severe weather conditions are key elements for mission success in asymmetric warfare. To support these capabilities for the dismounted soldier, AIM has developed a family of stand-alone thermal weapon sights based on high performance cooled IR-modules which are used e.g. in the infantryman of the future program of the German army (IdZ). The design driver for these sights is a long ID range <1500m for the NATO standard target to cover the operational range of a platoon with the engagement range of .50 cal rifles, 40mm AGLs or for reconnaissance tasks. The most recent sight WBZG has just entered into serial production for the IdZ enhanced system of the German army with additional capabilities like a wireless data link to the soldier backbone computer. Minimum size, weight and power (SWaP) are most critical requirements for the dismounted soldiers' equipment and sometimes push a decision towards uncooled equipment with marginal performance referring to the outstanding challenges in current asymmetric warfare, e.g. the capability to distinguish between combatants and non-combatants in adequate ranges. To provide the uncompromised e/o performance with SWaP parameters close to uncooled, AIM has developed a new thermal weapon sight based on high operating temperature (HOT) MCT MWIR FPAs together with a new low power single piston stirling cooler. In basic operation the sight is used as a clip-on in front of the rifle scope. An additional eyepiece for stand-alone targeting with e.g. AGLs or a biocular version for relaxed surveillance will be available. The paper will present details of the technologies applied for such long range cooled sights with size, weight and power close to uncooled.

Breiter, R.; Ihle, T.; Wendler, J.; Rühlich, I.; Ziegler, J.

2013-06-01

342

ANALYSIS OF A HIGH TEMPERATURE GAS-COOLED REACTOR POWERED HIGH TEMPERATURE ELECTROLYSIS HYDROGEN PLANT  

SciTech Connect

An updated reference design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322°C and 750°C, respectively. The reactor heat is used to produce heat and electric power to the HTE plant. A Rankine steam cycle with a power conversion efficiency of 44.4% was used to provide the electric power. The electrolysis unit used to produce hydrogen includes 1.1 million cells with a per-cell active area of 225 cm2. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 42.8% at a hydrogen production rate of 1.85 kg/s (66 million SCFD) and an oxygen production rate of 14.6 kg/s (33 million SCFD). An economic analysis of this plant was performed with realistic financial and cost estimating The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a competitive cost. A cost of $3.03/kg of hydrogen was calculated assuming an internal rate of return of 10% and a debt to equity ratio of 80%/20% for a reactor cost of $2000/kWt and $2.41/kg of hydrogen for a reactor cost of $1400/kWt.

M. G. McKellar; E. A. Harvego; A. M. Gandrik

2010-11-01

343

Interim Report: Air-Cooled Condensers for Next Generation Geothermal Power Plants Improved Binary Cycle Performance  

SciTech Connect

As geothermal resources that are more expensive to develop are utilized for power generation, there will be increased incentive to use more efficient power plants. This is expected to be the case with Enhanced Geothermal System (EGS) resources. These resources will likely require wells drilled to depths greater than encountered with hydrothermal resources, and will have the added costs for stimulation to create the subsurface reservoir. It is postulated that plants generating power from these resources will likely utilize the binary cycle technology where heat is rejected sensibly to the ambient. The consumptive use of a portion of the produced geothermal fluid for evaporative heat rejection in the conventional flash-steam conversion cycle is likely to preclude its use with EGS resources. This will be especially true in those areas where there is a high demand for finite supplies of water. Though they have no consumptive use of water, using air-cooling systems for heat rejection has disadvantages. These systems have higher capital costs, reduced power output (heat is rejected at the higher dry-bulb temperature), increased parasitics (fan power), and greater variability in power generation on both a diurnal and annual basis (larger variation in the dry-bulb temperature). This is an interim report for the task ‘Air-Cooled Condensers in Next- Generation Conversion Systems’. The work performed was specifically aimed at a plant that uses commercially available binary cycle technologies with an EGS resource. Concepts were evaluated that have the potential to increase performance, lower cost, or mitigate the adverse effects of off-design operation. The impact on both cost and performance were determined for the concepts considered, and the scenarios identified where a particular concept is best suited. Most, but not all, of the concepts evaluated are associated with the rejection of heat. This report specifically addresses three of the concepts evaluated: the use of recuperation, the use of turbine reheat, and the non-consumptive use of EGS make-up water to supplement heat rejection

Daniel S. Wendt; Greg L. Mines

2010-09-01

344

Experimental investigation of an ammonia-based combined power and cooling cycle  

NASA Astrophysics Data System (ADS)

A novel ammonia-water thermodynamic cycle, capable of producing both power and refrigeration, was proposed by D. Yogi Goswami. The binary mixture exhibits variable boiling temperatures during the boiling process, which leads to a good thermal match between the heating fluid and working fluid for efficient heat source utilization. The cycle can be driven by low temperature sources such as solar, geothermal, and waste heat from a conventional power cycle, reducing the reliance on high temperature sources such as fossil fuels. A theoretical simulation of the cycle at heat source temperatures obtainable from low and mid temperature solar collectors showed that the ideal cycle could produce power and refrigeration at a maximum exergy efficiency, defined as the ratio of the net work and refrigeration output to the change in availability of the heat source, of over 60%. The exergy efficiency is a useful measure of the cycle's performance as it compares the effectiveness of different cycles in harnessing the same source. An experimental system was constructed to demonstrate the feasibility of the cycle and to compare the experimental results with the theoretical simulations. In this first phase of experimentation, the turbine expansion was simulated with a throttling valve and a heat exchanger. Results showed that the vapor generation and absorption condensation processes work experimentally. The potential for combined turbine work and refrigeration output was evidenced in operating the system. Analysis of losses led to modifications in the system design, which were implemented to yield improvements in heat exchange, vapor generation, pump performance and overall stability. The research that has been conducted verifies the potential of the power and cooling cycle as an alternative to using conventional fossil fuel technologies. The research that continues is to further demonstrate the concept and direct it towards industry. On the large scale, the cycle can be used for industrial power production or as a central power plant for a community, with refrigeration produced as required by the application. On the small scale, an affordable residential or commercial unit could allow independent electricity generation for the home or business while also cooling it.

Tamm, Gunnar Olavi

345

Confined flow multiple beam shaping at the powerful klystron for the superconducting linear electron-positron colliders  

NASA Astrophysics Data System (ADS)

The results of modeling of the electro-optic system proposed and designed for the powerful multiple beam klystron Toshiba E3736 have been represented. Toshiba E3736 is the 10MW L-band six-beam klystron being developed for the superconductive accelerator projects TESLA (XFEL), ILC. The key features of device are the new compact scheme of the confined flow multiple beam shaping, the most low cathode loading (<2.1 A/cm2) in comparison with analogues, a controlled beamlet size (diameter) in the drift tubes of klystron.

Larionov, A. V.

2006-05-01

346

DEPOSITION OF NIOBIUM AND OTHER SUPERCONDUCTING MATERIALS WITH HIGH POWER IMPULSE MAGNETRON SPUTTERING: CONCEPT AND FIRST RESULTS  

SciTech Connect

Niobium coatings on copper cavities have been considered as a cost-efficient replacement of bulk niobium RF cavities, however, coatings made by magnetron sputtering have not quite lived up to high expectations due to Q-slope and other issues. High power impulse magnetron sputtering (HIPIMS) is a promising emerging coatings technology which combines magnetron sputtering with a pulsed power approach. The magnetron is turned into a metal plasma source by using very high peak power density of ~ 1 kW/cm{sup 2}. In this contribution, the cavity coatings concept with HIPIMS is explained. A system with two cylindrical, movable magnetrons was set up with custom magnetrons small enough to be inserted into 1.3 GHz cavities. Preliminary data on niobium HIPIMS plasma and the resulting coatings are presented. The HIPIMS approach has the potential to be extended to film systems beyond niobium, including other superconducting materials and/or multilayer systems.

High Current Electronics Institute, Tomsk, Russia; Anders, Andre; Mendelsberg, Rueben J.; Lim, Sunnie; Mentink, Matthijs; Slack, Jonathan L.; Wallig, Joseph G.; Nollau, Alexander V.; Yushkov, Georgy Yu.

2011-07-24

347

The potential for solar powered single-stage desiccant cooling in southern Europe  

Microsoft Academic Search

Desiccant cooling is an environmentally friendly technology which can be used to condition the internal environment of buildings. Unlike conventional air conditioning systems, which rely on electrical energy to drive the cooling cycle, desiccant cooling is a heat driven cycle. Desiccant cooling systems have been used successfully in northern Europe and a number of studies have demonstrated that solar energy

P. Mavroudaki; C. B. Beggs; P. A. Sleigh; S. P. Halliday

2002-01-01

348

Nuclear technology and potential ripple effect of superconducting magnets for fusion power plant  

Microsoft Academic Search

In a fusion reactor plant, a neutral beam injector (NBI) will be operated for a long time, and it will allow neutron streaming from NBI ports to outside of the plasma vacuum vessel. This fact requires that the superconducting magnets develop nuclear technology to maintain high performance and to reduce activation of the magnet components. In this report, the background

Arata Nishimura; Takeo Muroga; Takao Takeuchi; Takeo Nishitani; Atsuhiko Morioka

2006-01-01

349

Investigation of the power losses in a laminated dipole magnet with superconducting coils  

Microsoft Academic Search

Dynamic processes in a window-frame dipole with superconducting windings and a cold, laminated iron yoke have been investigated experimentally at JINR (Dubna, Russia), and theoretically at GSI (Darmstadt, Germany). The main aim of these investigations was a reduction of energy losses in the yoke during ramping. These losses are produced mainly by energy dissipation due to eddy currents and hysteresis

Alexander Kalimov; Egbert Fischer; Guenter Hess; Gebhard Moritz; Carsten Mühle

2004-01-01

350

Experiments on solar photovoltaic power generation using concentrator and liquid cooling  

NASA Technical Reports Server (NTRS)

Calculations and experimental data are presented leading to the development of a practical, economical solar photovoltaic power supply. The concept involves concentration of sunlight up to about 100 times normal solar intensity in a solar tracking collector and directing this to an array of solar cells. The cells are immersed in water circulated from a thermal reservoir which limits cell temperature rise to about 20 C above ambient during the day and which cools to ambient temperature during the night. Experiments were conducted on solar cells using a Fresnel lens for magnification, a telescope equatorial mount with clock drive, and tap water circulated through the solar cell holder cavity. Test results show that cells operate satisfactorily under these conditions. Power outputs achieved experimentally with cell optimized for 25 suns were linear with concentration to about 15 suns. Cells optimized for 100 suns were not available, but a corresponding linear relation of power output with concentration is anticipated. Test results have been used in a design analysis of the cost of systems utilizing this technique.

Beam, B. H.; Hansen, C. F.

1975-01-01

351

Overturning the Case for Gravitational Powering in the Prototypical Cooling Ly? Nebula  

NASA Astrophysics Data System (ADS)

The Nilsson et al. Ly? nebula has often been cited as the most plausible example of an Ly? nebula powered by gravitational cooling. In this paper, we bring together new data from the Hubble Space Telescope and the Herschel Space Observatory as well as comparisons to recent theoretical simulations in order to revisit the questions of the local environment and most likely power source for the Ly? nebula. In contrast to previous results, we find that this Ly? nebula is associated with six nearby galaxies and an obscured AGN that is offset by ?4? ? 30 kpc from the Ly? peak. The local region is overdense relative to the field, by a factor of ?10, and at low surface brightness levels the Ly? emission appears to encircle the position of the obscured AGN, highly suggestive of a physical association. At the same time, we confirm that there is no compact continuum source located within ?2–3? ? 15–23 kpc of the Ly? peak. Since the latest cold accretion simulations predict that the brightest Ly? emission will be coincident with a central growing galaxy, we conclude that this is actually a strong argument against, rather than for, the idea that the nebula is gravitationally powered. While we may be seeing gas within cosmic filaments, this gas is primarily being lit up, not by gravitational energy, but due to illumination from a nearby buried AGN.

Prescott, Moire K. M.; Momcheva, Ivelina; Brammer, Gabriel B.; Fynbo, Johan P. U.; Møller, Palle

2015-03-01

352

System for thermal energy storage, space heating and cooling and power conversion  

DOEpatents

An integrated system for storing thermal energy, for space heating and cong and for power conversion is described which utilizes the reversible thermal decomposition characteristics of two hydrides having different decomposition pressures at the same temperature for energy storage and space conditioning and the expansion of high-pressure hydrogen for power conversion. The system consists of a plurality of reaction vessels, at least one containing each of the different hydrides, three loops of circulating heat transfer fluid which can be selectively coupled to the vessels for supplying the heat of decomposition from any appropriate source of thermal energy from the outside ambient environment or from the spaces to be cooled and for removing the heat of reaction to the outside ambient environment or to the spaces to be heated, and a hydrogen loop for directing the flow of hydrogen gas between the vessels. When used for power conversion, at least two vessels contain the same hydride and the hydrogen loop contains an expansion engine. The system is particularly suitable for the utilization of thermal energy supplied by solar collectors and concentrators, but may be used with any source of heat, including a source of low-grade heat.

Gruen, Dieter M. (Downers Grove, IL); Fields, Paul R. (Chicago, IL)

1981-04-21

353

High power RF test of an 805 MHz RF cavity for a muon cooling channel  

SciTech Connect

We present recent high power RF test results on an 805 MHz cavity for a muon cooling experiment at Lab G in Fermilab. In order to achieve high accelerating gradient for large transverse emittance muon beams, the cavity design has adopted a pillbox like shape with 16 cm diameter beam iris covered by thin Be windows, which are demountable to allow for RF tests of different windows. The cavity body is made from copper with stiff stainless steel rings brazed to the cavity body for window attachments. View ports and RF probes are available for visual inspections of the surface of windows and cavity and measurement of the field gradient. Maximum of three thermo-couples can be attached to the windows for monitoring the temperature gradient on the windows caused by RF heating. The cavity was measured to have Q{sub 0} of about 15,000 with copper windows and coupling constant of 1.3 before final assembling. A 12 MW peak power klystron is available at Lab G in Fermilab for the high power test. The cavity and coupler designs were performed using the MAFIA code in the frequency and the time domain. Numerical simulation results and cold test measurements on the cavity and coupler will be presented for comparisons.

Li, Derun; Corlett, J.; MacGill, R.; Rimmer, R.; Wallig, J.; Zisman, M.; Moretti, A.; Qian, Z.; Wu, V.; Summers, D.; Norem, J.

2002-05-30

354

Solid-Core, Gas-Cooled Reactor for Space and Surface Power  

SciTech Connect

The solid-core, gas-cooled, Submersion-Subcritical Safe Space (S and 4) reactor is developed for future space power applications and avoidance of single point failures. The Mo-14%Re reactor core is loaded with uranium nitride fuel in enclosed cavities, cooled by He-30%Xe, and sized to provide 550 kWth for seven years of equivalent full power operation. The beryllium oxide reflector disassembles upon impact on water or soil. In addition to decreasing the reactor and shadow shield mass, Spectral Shift Absorber (SSA) materials added to the reactor core ensure that it remains subcritical in the worst-case submersion accident. With a 0.1 mm thick boron carbide coating on the outside surface of the core block and 0.25 mm thick iridium sleeves around the fuel stacks, the reflector outer diameter is 43.5 cm and the combined reactor and shadow shield mass is 935.1 kg. With 12.5 atom% gadolinium-155 added to the fuel, 2.0 mm diameter gadolinium-155 sesquioxide intersititial pins, and a 0.1 mm thick gadolinium-155 sesquioxide coating, the S and 4 reactor has a slightly smaller reflector outer diameter of 43.0 cm, and a total reactor and shield mass of 901.7 kg. With 8.0 atom% europium-151 added to the fuel, 2.0 mm diameter europium-151 sesquioxide interstitial pins, and a 0.1 mm thick europium-151 sesquioxide coating, the reflector's outer diameter and the total reactor and shield mass are further reduced to 41.5 cm and 869.2 kg, respect0011ive.

King, Jeffrey C.; El-Genk, Mohamed S. [Institute for Space and Nuclear Power Studies, University of New Mexico, Albuquerque, NM 87131 (United States); Chemical and Nuclear Engineering Dept., University of New Mexico, Albuquerque, NM 87131 (United States)

2006-01-20

355

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 625°C 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

356

Passive radiative cooling of a HTS coil for attitude orbit control in micro-spacecraft  

NASA Astrophysics Data System (ADS)

This paper proposes a novel radiative cooling system for a high temperature superconducting (HTS) coil for an attitude orbit control system in nano- and micro-spacecraft missions. These days, nano-spacecraft (1-10 kg) and micro-spacecraft (10-100 kg) provide space access to a broader range of spacecraft developers and attract interest as space development applications. In planetary and high earth orbits, most previous standard-size spacecraft used thrusters for their attitude and orbit control, which are not available for nano- and micro-spacecraft missions because of the strict power consumption, space, and weight constraints. This paper considers orbit and attitude control methods that use a superconducting coil, which interacts with on-orbit space plasmas and creates a propulsion force. Because these spacecraft cannot use an active cooling system for the superconducting coil because of their mass and power consumption constraints, this paper proposes the utilization of a passive radiative cooling system, in which the superconducting coil is thermally connected to the 3 K cosmic background radiation of deep space, insulated from the heat generation using magnetic holders, and shielded from the sun. With this proposed cooling system, the HTS coil is cooled to 60 K in interplanetary orbits. Because the system does not use refrigerators for its cooling system, the spacecraft can achieve an HTS coil with low power consumption, small mass, and low cost.

Inamori, Takaya; Ozaki, Naoya; Saisutjarit, Phongsatorn; Ohsaki, Hiroyuki

2015-02-01

357

HOM damping properties of fundamental power couplers in the superconducting electron gun of the energy recovery LINAC at Brookhaven National Laboratory  

SciTech Connect

Among the accelerator projects under construction at the Relativistic Heavy Ion Collider (RHIC) is an R and D energy recovery LINAC (ERL) test facility. The ERL includes both a five-cell superconducting cavity as well as a superconducting, photoinjector electron gun. Because of the high-charge and high-current demands, effective higher-order mode (HOM) damping is essential, and several strategies are being pursued. Among these is the use of the fundamental power couplers as a means for damping some HOMs. Simulation studies have shown that the power couplers can play a substantial role in damping certain HOMs, and this presentation discusses these studies along with measurements.

Hammons, L.; Hahn, H.

2011-03-28

358

Comprehensive Evaluation of Biological Growth Control by Chlorine-Based Biocides in Power Plant Cooling Systems Using Tertiary Effluent  

PubMed Central

Abstract Recent studies have shown that treated municipal wastewater can be a reliable cooling water alternative to fresh water. However, elevated nutrient concentration and microbial population in wastewater lead to aggressive biological proliferation in the cooling system. Three chlorine-based biocides were evaluated for the control of biological growth in cooling systems using tertiary treated wastewater as makeup, based on their biocidal efficiency and cost-effectiveness. Optimal chemical regimens for achieving successful biological growth control were elucidated based on batch-, bench-, and pilot-scale experiments. Biocide usage and biological activity in planktonic and sessile phases were carefully monitored to understand biological growth potential and biocidal efficiency of the three disinfectants in this particular environment. Water parameters, such as temperature, cycles of concentration, and ammonia concentration in recirculating water, critically affected the biocide performance in recirculating cooling systems. Bench-scale recirculating tests were shown to adequately predict the biocide residual required for a pilot-scale cooling system. Optimal residuals needed for proper biological growth control were 1, 2–3, and 0.5–1?mg/L as Cl2 for NaOCl, preformed NH2Cl, and ClO2, respectively. Pilot-scale tests also revealed that Legionella pneumophila was absent from these cooling systems when using the disinfectants evaluated in this study. Cost analysis showed that NaOCl is the most cost-effective for controlling biological growth in power plant recirculating cooling systems using tertiary-treated wastewater as makeup. PMID:23781129

Chien, Shih-Hsiang; Dzombak, David A.; Vidic, Radisav D.

2013-01-01

359

DEVELOP A CONCENTRATED SOLAR POWER-BASED THERMAL COOLING SYSTEM VIA SIMULATION AND EXPERIMENTAL STUDIES  

EPA Science Inventory

A small scale CSP-based cooling system prototype (300W cooling capacity) and the system performance simulation tool will be developed as a proof of concept. Practical issues will be identified to improve our design. ...

360

Hybrid superconducting magnetic suspensions  

SciTech Connect

Superconductors, especially high T{sub c} ones, are the most attractive materials to design stable and fully passive magnetic suspensions which have to control five degrees of freedom. The hybrid superconducting magnetic suspensions present high performances and a simple cooling mode. They consist of a permanent magnet bearing, stabilized by a suitable magnet-superconductor structure. Several designs are given and compared in terms of forces and stiffnesses. The design of the magnet bearing plays an important part. The superconducting magnetic bearing participates less in levitation but must provide a high stabilizing stiffness. This is achieved by the magnet configuration, a good material in term of critical current density and field cooling. A hybrid superconducting suspension for a flywheel is presented. This system consists of a magnet thrust bearing stabilized by superconductors interacting with an alternating polarity magnet structure. First tests and results are reported. Superconducting materials are magnetically melt-textured YBaCuO.

Tixador, P.; Hiebel, P.; Brunet, Y. [CNRS-CRTBT/LEG, Grenoble (France)] [CNRS-CRTBT/LEG, Grenoble (France); Chaud, X.; Gautier-Picard, P. [CNRS-EPM-Matformag, Grenoble (France)] [CNRS-EPM-Matformag, Grenoble (France)

1996-07-01

361

A model to predict total chlorine residue in the cooling seawater of a power plant using iodine colorimetric method.  

PubMed

A model experiment monitoring the fate of total residue oxidant (TRO) in water at a constant temperature and salinity indicated that it decayed exponentially with time, and with TRO decaying faster in seawater than in distilled water. The reduction of TRO by temperature ( degrees K) was found to fit a curvilinear relationship in distilled water (r(2) = 0.997) and a linear relationship in seawater (r(2) = 0.996). Based on the decay rate, flow rate, and the length of cooling water flowing through at a given temperature, the TRO level in the cooling water of a power plant could be estimated using the equation developed in this study. This predictive model would provide a benchmark for power plant operators to adjust the addition of chlorine to levels necessary to control bio-fouling of cooling water intake pipelines, but without irritating ambient marine organisms. PMID:19325768

Wang, Jih-Terng; Chen, Ming-Hui; Lee, Hung-Jen; Chang, Wen-Been; Chen, Chung-Chi; Pai, Su-Cheng; Meng, Pei-Jie

2008-04-01

362

A Model to Predict Total Chlorine Residue in the Cooling Seawater of a Power Plant Using Iodine Colorimetric Method  

PubMed Central

A model experiment monitoring the fate of total residue oxidant (TRO) in water at a constant temperature and salinity indicated that it decayed exponentially with time, and with TRO decaying faster in seawater than in distilled water. The reduction of TRO by temperature (°K) was found to fit a curvilinear relationship in distilled water (r2 = 0.997) and a linear relationship in seawater (r2 = 0.996). Based on the decay rate, flow rate, and the length of cooling water flowing through at a given temperature, the TRO level in the cooling water of a power plant could be estimated using the equation developed in this study. This predictive model would provide a benchmark for power plant operators to adjust the addition of chlorine to levels necessary to control bio-fouling of cooling water intake pipelines, but without irritating ambient marine organisms. PMID:19325768

Wang, Jih-Terng; Chen, Ming-Hui; Lee, Hung-Jen; Chang, Wen-Been; Chen, Chung-Chi; Pai, Su-Cheng; Meng, Pei-Jie

2008-01-01

363

Minnesota Project: district heating and cooling through power plant retrofit and distribution network. Final report. Phase 1. [Minnesota Project  

SciTech Connect

Appendices are presented for the Minnesota Project: District Heating and Cooling Through Power Plant Retrofit and Distribution Network. These are: SYNTHA results (SYNTHA II is a proprietary program of the SYNTHA Corporation); Market Survey Questionnaire: Environmental Review Procedures; Public Service Commission Regulation of District Heating; Energy Use Normalization Procedures; Power Plant Description; Letters of Commitment; Bond Opinion and Issuance; and Marvin Koeplin Letter, Chairman of Public Service Commission, Moorehead, Minnesota.

none,

1980-01-01

364

Superconducting magnet  

NASA Technical Reports Server (NTRS)

Extensive computer based engineering design effort resulted in optimization of a superconducting magnet design with an average bulk current density of approximately 12KA/cm(2). Twisted, stranded 0.0045 inch diameter NbTi superconductor in a copper matrix was selected. Winding the coil from this bundle facilitated uniform winding of the small diameter wire. Test coils were wound using a first lot of the wire. The actual packing density was measured from these. Interwinding voltage break down tests on the test coils indicated the need for adjustment of the wire insulation on the lot of wire subsequently ordered for construction of the delivered superconducting magnet. Using the actual packing densities from the test coils, a final magnet design, with the required enhancement and field profile, was generated. All mechanical and thermal design parameters were then also fixed. The superconducting magnet was then fabricated and tested. The first test was made with the magnet immersed in liquid helium at 4.2K. The second test was conducted at 2K in vacuum. In the latter test, the magnet was conduction cooled from the mounting flange end.

1985-01-01

365

MoXy fiber with active cooling cap for bovine prostate vaporization with high power 200W 532 nm laser  

NASA Astrophysics Data System (ADS)

A novel MoXyTM fiber delivery device with Active Cooling Cap (ACCTM) is designed to transmit up to 180W of 532 nm laser light to treat benign prostatic hyperplasia (BPH). Under such high power tissue ablation, effective cooling is key to maintaining fiber power transmission and ensuring the reliability of the fiber delivery device To handle high power and reduce fiber degradation, the MoXy fiber features a larger core size (750 micrometer) and an internal fluid channel to ensure better cooling of the fiber tip to prevent the cap from burning, detaching, or shattering during the BPH treatment. The internal cooling channel was created with a metal cap and tubing that surrounds the optical fiber. In this study MoXy fibers were used to investigate the effect of power levels of 120 and 200 W on in-vitro bovine prostate ablation using a 532 nm XPSTM laser system. For procedures requiring more than 100 kJ, the MoXy fiber at 200W removed tissue at twice the rate of the current HPS fiber at 120W. The fiber maintained a constant tissue vaporization rate during the entire tissue ablation process. The coagulation at 200W was about 20% thicker than at 120W. In conclusion, the new fibers at 200W doubled the tissue removal rate, maintained vaporization efficiency throughout delivery of 400kJ energy, and induced similar coagulation to the existing HPS fiber at 120W.

Peng, Steven Y.; Kang, Hyun Wook; Pirzadeh, Homa; Stinson, Douglas

2011-03-01

366

User's manual for the BNW-I optimization code for dry-cooled power plants. Volume I  

Microsoft Academic Search

This User's Manual provides information on the use and operation of three versions of BNW-I, a computer code developed by Battelle, Pacific Northwest Laboratory (PNL) as a part of its activities under the ERDA Dry Cooling Tower Program. These three versions of BNW-I were used as reported elsewhere to obtain comparative incremental costs of electrical power production by two advanced

D. J. Braun; D. J. Daniel; W. V. De Mier; D. W. Faletti; L. E. Wiles

2011-01-01

367

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 125°C to 200°C. 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 10-25°C. 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 5-10°C in the EAHE. Vertical pipes were used to lower the temperature of water by 5°C 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 10-20°C 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

368

Helium Transfer System for the Superconducting Devices at NSRRC  

NASA Astrophysics Data System (ADS)

A helium cryogenic plant with a maximum cooling power of 450 W at 4.5K was installed at the end of the year 2003. This plant has provide the cooling power for the test of one superconducting cavity and the commission of one superconducting magnet for nine months. In November 2004, we installed one helium transfer system in NSRRC's storage ring to fulfill the cooling requirement for the operation of one superconducting cavity and two superconducting magnets. This helium transfer system consists of a switch valve box and the nitrogen-shielding multi-channel transfer lines. The averaged heat leak to the helium process line (including the straight section, the joint, the elbow, the coupling) at liquid helium temperature is specified to be less than 0.1 W/m at 4.2K; the total heat leak of the switching valve box to helium process lines is less than 16 W at 4.2K. In this paper we present the function, design parameters and test result of the helium transfer system. Commissioning results of both the cavity and the magnets using this helium transfer system will be shown as well.

Li, H. C.; Hsiao, F. Z.; Chang, S. H.; Chiou, W. S.

2006-04-01

369

Electrical and thermal characterization of a novel high pressure gas cooled DC power cable  

NASA Astrophysics Data System (ADS)

High-temperature superconductors (HTS) allow power cables of substantially higher current density than conventional copper or aluminum cables. This is important for applications where a low mass and a low volume are critical such as naval, aeronautical and space applications. The novel type of cable under consideration is cooled by gaseous Helium at elevated pressure. Helium is known for having poor electric breakdown strength; therefore the dielectric capabilities of this type of cable must be tested under conditions similar to the envisaged operation. In order to study the dielectric performance we have designed and built a novel high pressure cryostat rated at 2.17 MPa which has been used for testing model cables of lengths of up to 1 m. The cryostat is an open system where the gas is not re-circulated. This allows maintaining a high purity of the gas. The target temperature range is between 40 K and 70 K. This substantially increases the critical current density of the HTS compared to 77 K, which is the typical temperature of cables cooled by liquid Nitrogen. The cryostat presented allows for adjusting the temperature and keeping it constant for the time necessary to run a complete dielectric characterization test. We give a detailed description of the cryostat. Measurements of partial discharge inception voltages as well as the temperature distribution along the model cables as a function of time are presented. Tests showed that the thermal insulation characteristics of this cryostat were sufficient for the dielectric tests of up to 1 h duration. The partial discharge inception voltage (PDIV) of the high voltage bushing was about 16 kV. These values are well within our design requirements.

Rodrigo, H.; Salmhofer, F.; Kwag, D. S.; Pamidi, S.; Graber, L.; Crook, D. G.; Ranner, S. L.; Dale, S. J.; Knoll, D.

2012-04-01

370

PREFACE: Superconducting materials Superconducting materials  

NASA Astrophysics Data System (ADS)

The discovery of superconductivity in 1911 was a great milestone in condensed matter physics. This discovery has resulted in an enormous amount of research activity. Collaboration among chemists and physicists, as well as experimentalists and theoreticians has given rise to very rich physics with significant potential applications ranging from electric power transmission to quantum information. Several superconducting materials have been synthesized. Crucial progress was made in 1987 with the discovery of high temperature superconductivity in copper-based compounds (cuprates) which have revealed new fascinating properties. Innovative theoretical tools have been developed to understand the striking features of cuprates which have remained for three decades the 'blue-eyed boy' for researchers in superconductor physics. The history of superconducting materials has been notably marked by the discovery of other compounds, particularly organic superconductors which despite their low critical temperature continue to attract great interest regarding their exotic properties. Last but not least, the recent observation of superconductivity in iron-based materials (pnictides) has renewed hope in reaching room temperature superconductivity. However, despite intense worldwide studies, several features related to this phenomenon remain unveiled. One of the fundamental key questions is the mechanism by which superconductivity takes place. Superconductors continue to hide their 'secret garden'. The new trends in the physics of superconductivity have been one of the two basic topics of the International Conference on Conducting Materials (ICoCoM2010) held in Sousse,Tunisia on 3-7 November 2010 and organized by the Tunisian Physical Society. The conference was a nice opportunity to bring together participants from multidisciplinary domains in the physics of superconductivity. This special section contains papers submitted by participants who gave an oral contribution at ICoCoM2010 and by invited authors selected by the editor. We are grateful to IUPAP, ICTP and the European Office of Aerospace Research and Development, Air Force Office of Scientific Research, United States Air Force Laboratory. We would like to acknowledge the authors for their careful work, and finally we thank Dr L Smith the publisher of Journal of Physics: Condensed Matter for her patience and help. Superconducting materials contents Raman spectrum in the pseudogap phase of the underdoped cuprates: effect of phase coherence and the signature of the KT-type superconducting transitionTao Li and Haijun Liao Pressure effects on Dirac fermions in ?-(BEDT-TTF)2I3Takahiro Himura, Takao Morinari and Takami Tohyama Effect of Zn doping in hole-type 1111 phase (Pr, Sr)FeAsOXiao Lin, Chenyi Shen, Chen Lv, Jianjian Miao, Hao Tan, Guanghan Cao and Zhu-An Xu Superconductivity and ferromagnetism in EuFe2(As1 - xPx)2*Guanghan Cao, Shenggao Xu, Zhi Ren, Shuai Jiang, Chunmu Feng and Zhu'an Xu OInhomogeneous superconductivity in organic conductors: the role of disorder and magnetic fieldS Haddad, S Charfi-Kaddour and J-P Pouget

Charfi Kaddour, Samia; Singleton, John; Haddad, Sonia

2011-11-01

371

Evaluation of gas-cooled pressurized phosphoric acid fuel cells for electric utility power generation  

NASA Astrophysics Data System (ADS)

Gas cooling is a more reliable, less expensive and a more simple alternative to conventional liquid cooling for heat removal from the phosphoric acid fuel cell (PAFC). The feasibility of gas-cooling was already demonstrated in atmospheric pressure stacks. Theoretical and experimental investigations of gas-cooling for pressurized PAFC are presented. Two approaches to gas cooling, Distributed Gas-Cooling (DIGAS) and Separated Gas-Cooling (SGC) were considered, and a theoretical comparison on the basis of cell performance indicated SGC to be superior to DIGAS. The feasibility of SGC was experimentally demonstrated by operating a 45-cell stack for 700 hours at pressure, and determining thermal response and the effect of other related parameters.

Faroque, M.

1983-09-01

372

Evaluation of Gas-Cooled Pressurized Phosphoric Acid Fuel Cells for Electric Utility Power Generation  

NASA Technical Reports Server (NTRS)

Gas cooling is a more reliable, less expensive and a more simple alternative to conventional liquid cooling for heat removal from the phosphoric acid fuel cell (PAFC). The feasibility of gas-cooling was already demonstrated in atmospheric pressure stacks. Theoretical and experimental investigations of gas-cooling for pressurized PAFC are presented. Two approaches to gas cooling, Distributed Gas-Cooling (DIGAS) and Separated Gas-Cooling (SGC) were considered, and a theoretical comparison on the basis of cell performance indicated SGC to be superior to DIGAS. The feasibility of SGC was experimentally demonstrated by operating a 45-cell stack for 700 hours at pressure, and determining thermal response and the effect of other related parameters.

Faroque, M.

1983-01-01

373

WET/DRY COOLING AND COOLING TOWER BLOWDOWN DISPOSAL IN SYNTHETIC FUEL AND STEAM-ELECTRIC POWER PLANTS  

EPA Science Inventory

This report extends the results of a previous study dealing with the detailed determination of consumptive water use and wet-solids residuals for coal and oil shale conversion plants and coal-fired steam-electric power generation plants located in the western United States. The p...

374

Technical analysis of a river basin-based model of advanced power plant cooling technologies for mitigating water management challenges  

NASA Astrophysics Data System (ADS)

Thermoelectric power plants require large volumes of water for cooling, which can introduce drought vulnerability and compete with other water needs. Alternative cooling technologies, such as cooling towers and hybrid wet-dry or dry cooling, present opportunities to reduce water diversions. This case study uses a custom, geographically resolved river basin-based model for eleven river basins in the state of Texas (the Brazos and San Jacinto-Brazos, Colorado and Colorado-Brazos, Cypress, Neches, Nueces, Red, Sabine, San Jacinto, and Trinity River basins), focusing on the Brazos River basin, to analyze water availability during drought. We utilized two existing water availability models for our analysis: (1) the full execution of water rights—a scenario where each water rights holder diverts the full permitted volume with zero return flow, and (2) current conditions—a scenario reflecting actual diversions with associated return flows. Our model results show that switching the cooling technologies at power plants in the eleven analyzed river basins to less water-intensive alternative designs can potentially reduce annual water diversions by 247-703 million m3—enough water for 1.3-3.6 million people annually. We consider these results in a geographic context using geographic information system tools and then analyze volume reliability, which is a policymaker's metric that indicates the percentage of total demand actually supplied over a given period. This geographic and volume reliability analysis serves as a measure of drought susceptibility in response to changes in thermoelectric cooling technologies. While these water diversion savings do not alleviate all reliability concerns, the additional streamflow from the use of dry cooling alleviates drought concerns for some municipal water rights holders and might also be sufficient to uphold instream flow requirements for important bays and estuaries on the Texas Gulf coast.

Stillwell, Ashlynn S.; Clayton, Mary E.; Webber, Michael E.

2011-07-01

375

Surface Superconductivity in Niobium for Superconducting RF Cavities0  

E-print Network

Surface Superconductivity in Niobium for Superconducting RF Cavities0 S. Casalbuoni1,2 , E) parameters of the ultrapure niobium used for the fabrication of the nine-cell 1.3 GHz cavities for the lin.3 GHz nine-cell cavities which are made from pure niobium and cooled by superfluid helium at 2 K. The 0

376

Electric Current Dependence of a Self-Cooling Device Consisting of Silicon Wafers Connected to a Power MOSFET  

NASA Astrophysics Data System (ADS)

A self-cooling device has been developed by combining a commercial n-channel power metal-oxide-semiconductor field-effect transistor (MOSFET) and single-crystalline Sb-doped n-type or B-doped p-type silicon wafers in order to improve the heat removal or cooling quantitatively. The electric current dependence of the temperature distribution in the self-cooling device and the voltage between the source and drain electrodes have been measured to estimate the Peltier heat flux. We found that the average temperature is decreased for a power MOSFET in which an electric current of 50 A flows. In particular, the average temperature of the power MOSFET was decreased by 2.7°C with the n-type Si wafer and by 3.5°C with the p-type Si wafer, although an electric current of 40 A makes little difference. This certainly warrants further work with improved measurement conditions. Nonetheless, the results strongly indicate that such n-type or p-type silicon wafers are candidate materials for use in self-cooling devices.

Nakatsugawa, H.; Okamoto, Y.; Kawahara, T.; Yamaguchi, S.

2014-06-01

377

Use of caged fish for mariculture and environmental monitoring in a power-plant cooling-water system  

E-print Network

fishes were cultured in cages in the intake area, at the head of the 9. S-km discharge canal, and at three locations in the 1053-ha ccoling lake of a power plant near upper Galveston Bay, fran 1 September 1975 to 11 September 1976 both to explore... discharge canal, and in the cooling lake remained rare stable, (3) Dissolved oxygen levels and pH generally increased frcm intake area to discharge canal to cooling lake, which probably indicated increases in primary production and improvensnts in overall...

Chamberlain, George William

1978-01-01

378

European roadmap on superconductive electronics - status and perspectives  

NASA Astrophysics Data System (ADS)

Executive SummaryFor four decades semiconductor electronics has followed Moore’s law: with each generation of integration the circuit features became smaller, more complex and faster. This development is now reaching a wall so that smaller is no longer any faster. The clock rate has saturated at about 3-5 GHz and the parallel processor approach will soon reach its limit. The prime reason for the limitation the semiconductor electronics experiences is not the switching speed of the individual transistor, but its power dissipation and thus heat. Digital superconductive electronics is a circuit- and device-technology that is inherently faster at much less power dissipation than semiconductor electronics. It makes use of superconductors and Josephson junctions as circuit elements, which can provide extremely fast digital devices in a frequency range - dependent on the material - of hundreds of GHz: for example a flip-flop has been demonstrated that operated at 750 GHz. This digital technique is scalable and follows similar design rules as semiconductor devices. Its very low power dissipation of only 0.1 ?W per gate at 100 GHz opens the possibility of three-dimensional integration. Circuits like microprocessors and analogue-to-digital converters for commercial and military applications have been demonstrated. In contrast to semiconductor circuits, the operation of superconducting circuits is based on naturally standardized digital pulses the area of which is exactly the flux quantum ?0. The flux quantum is also the natural quantization unit for digital-to-analogue and analogue-to-digital converters. The latter application is so precise, that it is being used as voltage standard and that the physical unit ‘Volt’ is defined by means of this standard. Apart from its outstanding features for digital electronics, superconductive electronics provides also the most sensitive sensor for magnetic fields: the Superconducting Quantum Interference Device (SQUID). Amongst many other applications SQUIDs are used as sensors for magnetic heart and brain signals in medical applications, as sensor for geological surveying and food-processing and for non-destructive testing. As amplifiers of electrical signals, SQUIDs can nearly reach the theoretical limit given by Quantum Mechanics. A further important field of application is the detection of very weak signals by ‘transition-edge’ bolometers, superconducting nanowire single-photon detectors, and superconductive tunnel junctions. Their application as radiation detectors in a wide frequency range, from microwaves to X-rays is now standard. The very low losses of superconductors have led to commercial microwave filter designs that are now widely used in the USA in base stations for cellular phones and in military communication applications. The number of demonstrated applications is continuously increasing and there is no area in professional electronics, in which superconductive electronics cannot be applied and surpasses the performance of classical devices. Superconductive electronics has to be cooled to very low temperatures. Whereas this was a bottleneck in the past, cooling techniques have made a huge step forward in recent years: very compact systems with high reliability and a wide range of cooling power are available commercially, from microcoolers of match-box size with milli-Watt cooling power to high-reliability coolers of many Watts of cooling power for satellite applications. Superconductive electronics will not replace semiconductor electronics and similar room-temperature techniques in standard applications, but for those applications which require very high speed, low-power consumption, extreme sensitivity or extremely high precision, superconductive electronics is superior to all other available techniques. To strengthen the European competitiveness in superconductor electronics research projects have to be set-up in the following field: Ultra-sensitive sensing and imaging. Quantum measurement instrumentation. Advanced analogue-to-digital converters. Superconductive

Anders, S.; Blamire, M. G.; Buchholz, F.-Im.; Crété, D.-G.; Cristiano, R.; Febvre, P.; Fritzsch, L.; Herr, A.; Il'ichev, E.; Kohlmann, J.; Kunert, J.; Meyer, H.-G.; Niemeyer, J.; Ortlepp, T.; Rogalla, H.; Schurig, T.; Siegel, M.; Stolz, R.; Tarte, E.; ter Brake, H. J. M.; Toepfer, H.; Villegier, J.-C.; Zagoskin, A. M.; Zorin, A. B.

2010-12-01

379

Micro Cooling, Heating, and Power (Micro-CHP) and Bio-Fuel Center, Mississippi State University  

SciTech Connect

Initially, most micro-CHP systems will likely be designed as constant-power output or base-load systems. This implies that at some point the power requirement will not be met, or that the requirement will be exceeded. Realistically, both cases will occur within a 24-hour period. For example, in the United States, the base electrical load for the average home is approximately 2 kW while the peak electrical demand is slightly over 4 kW. If a 3 kWe micro- CHP system were installed in this situation, part of the time more energy will be provided than could be used and for a portion of the time more energy will be required than could be provided. Jalalzadeh-Azar [6] investigated this situation and presented a comparison of electrical- and thermal-load-following CHP systems. In his investigation he included in a parametric analysis addressing the influence of the subsystem efficiencies on the total primary energy consumption as well as an economic analysis of these systems. He found that an increase in the efficiencies of the on-site power generation and electrical equipment reduced the total monthly import of electricity. A methodology for calculating performance characteristics of different micro-CHP system components will be introduced in this article. Thermodynamic cycles are used to model each individual prime mover. The prime movers modeled in this article are a spark-ignition internal combustion engine (Otto cycle) and a diesel engine (Diesel cycle). Calculations for heat exchanger, absorption chiller, and boiler modeling are also presented. The individual component models are then linked together to calculate total system performance values. Performance characteristics that will be observed for each system include maximum fuel flow rate, total monthly fuel consumption, and system energy (electrical, thermal, and total) efficiencies. Also, whether or not both the required electrical and thermal loads can sufficiently be accounted for within the system specifications is observed. Case study data for various micro-CHP system configurations have been discussed and compared. Comparisons are made of the different prime mover/fuel combinations. Also, micro- CHP monthly energy cost results are compared for each system configuration to conventional monthly utility costs for equivalent monthly building power, heating, and cooling requirements.

Louay Chamra

2008-09-26

380

Superconductivity in general domains Virginie Bonnaillie  

E-print Network

Superconductivity in general domains Virginie Bonnaillie D´epartement de Math´ematiques, UMR CNRS.Bonnaillie@math.u-psud.fr Abstract Motivated by the superconductivity, we are interested in the funda- mental state of the Schr A superconducting sample cooled below a certain critical temperature TC al- lows the current to flow

Bonnaillie-Noël, Virginie

381

Superconducting wire with improved strain characteristics  

DOEpatents

A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improves the strain characteristics of the wire.

Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (E. Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

1982-01-01

382

Superconducting wire with improved strain characteristics  

DOEpatents

A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improve the strain characteristics of the wire.

Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (East Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

1982-01-01

383

Nonequilibrium Thermoelectrics: Low-Cost, High-Performance Materials for Cooling and Power Generation  

SciTech Connect

Thermoelectric materials can be made into coolers (TECs) that use electricity to develop a temperature difference, cooling something, or generators (TEGs) that convert heat directly to electricity. One application of TEGs is to place them in a waste heat stream to recuperate some of the power being lost and putting it to use more profitably. To be effective thermoelectrics, however, materials must have both high electrical conductivity and low thermal conductivity, a combination rarely found in nature. Materials selection and processing has led to the development of several systems with a figure of merit, ZT, of nearly unity. By using non-equilibrium techniques, we have fabricated higher efficiency thermoelectric materials. The process involves creating an amorphous material through melt spinning and then sintering it with either spark plasma or a hot press for as little as two minutes. This results in a 100% dense material with an extremely fine grain structure. The grain boundaries appear to retard phonons resulting in a reduced thermal conductivity while the electrons move through the material relatively unchecked. The techniques used are low-cost and scaleable to support industrial manufacturing.

Li, Q.

2011-05-18

384

Magnetocaloric properties and critical behavior of high relative cooling power FeNiB nanoparticles  

SciTech Connect

Low cost magnetocaloric nanomaterials have attracted considerable attention for energy efficient applications. We report a very high relative cooling power (RCP) in a study of the magnetocaloric effect in quenched FeNiB nanoparticles. RCP increases from 89.8 to 640?J kg{sup ?1} for a field change of 1 and 5?T, respectively, these values are the largest for rare earth free iron based magnetocaloric nanomaterials. To investigate the magnetocaloric behavior around the Curie temperature (T{sub C}), the critical behavior of these quenched nanoparticles was studied. Detailed analysis of the magnetic phase transition using the modified Arrott plot, Kouvel-Fisher method, and critical isotherm plots yields critical exponents of ??=?0.364, ??=?1.319, ??=?4.623, and ??=??0.055, which are close to the theoretical exponents obtained from the 3D-Heisenberg model. Our results indicate that these FeNiB nanoparticles are potential candidates for magnetocaloric fluid based heat pumps and low grade waste heat recovery.

Chaudhary, V. [Interdisciplinary Graduate School, Nanyang Technological University, Singapore 639798 (Singapore); Energy Research Institute @NTU, Nanyang Technological University, Singapore 637553 (Singapore); School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Maheswar Repaka, D. V.; Chaturvedi, A.; Ramanujan, R. V., E-mail: ramanujan@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798 (Singapore); Sridhar, I. [School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore 639798 (Singapore)

2014-10-28

385

Thermal ecology of Naegleria fowleri from a power plant cooling reservoir  

SciTech Connect

The pathogenic, free-living amoeba Naegleria fowleri is the causative agent of human primary amebic meningoencephalitis. N. fowleri has been isolated from thermally elevated aquatic environments worldwide, but temperature factors associated with occurrence of the amoeba remain undefined. In this study, a newly created cooling reservoir (Clinton Lake, Illinois) was surveyed for Naegleria spp. before and after thermal additions from a nuclear power plant. Water and sediment samples were collected from heated and unheated arms of the reservoir and analyzed for the presence of thermophilic Naegleria spp. and pathogenic N. fowleri. Amoebae were identified by morphology, in vitro cultivation, temperature tolerance, mouse pathogenicity assay, and DNA restriction fragment length analysis. N. fowleri was isolated from the thermally elevated arm but not from the ambient-temperature arm of the reservoir. The probability of isolating thermophilic Naegleria and pathogenic N. fowleri increased significantly with temperature. Repetitive DNA restriction fragment profiles of the N. fowleri Clinton Lake isolates and a known N. fowleri strain of human origin were homogeneous.

Huizinga, H.W. (Illinois State Univ., Normal (USA)); McLaughlin, G.L. (Univ. of Illinois, Urbana (USA))

1990-07-01

386

Magnetocaloric properties and critical behavior of high relative cooling power FeNiB nanoparticles  

NASA Astrophysics Data System (ADS)

Low cost magnetocaloric nanomaterials have attracted considerable attention for energy efficient applications. We report a very high relative cooling power (RCP) in a study of the magnetocaloric effect in quenched FeNiB nanoparticles. RCP increases from 89.8 to 640 J kg-1 for a field change of 1 and 5 T, respectively, these values are the largest for rare earth free iron based magnetocaloric nanomaterials. To investigate the magnetocaloric behavior around the Curie temperature (TC), the critical behavior of these quenched nanoparticles was studied. Detailed analysis of the magnetic phase transition using the modified Arrott plot, Kouvel-Fisher method, and critical isotherm plots yields critical exponents of ? = 0.364, ? = 1.319, ? = 4.623, and ? = -0.055, which are close to the theoretical exponents obtained from the 3D-Heisenberg model. Our results indicate that these FeNiB nanoparticles are potential candidates for magnetocaloric fluid based heat pumps and low grade waste heat recovery.

Chaudhary, V.; Maheswar Repaka, D. V.; Chaturvedi, A.; Sridhar, I.; Ramanujan, R. V.

2014-10-01

387

Development of superconductive magnets  

NASA Technical Reports Server (NTRS)

Survey of superconductive magnets considers - stabilization problems, advances in materials and their uses, and design evolution. Uses of superconducting magnets in particle accelerators and bubble chambers, as well as possible applications in magnetohydrodynamic and thermonuclear power generation and levitation are discussed.

Laurence, J. C.

1970-01-01

388

New 30 kA power system at Fermilab and its use for measuring the effects of ripple current on the performance of superconducting high field magnets  

SciTech Connect

A new 30 kA, 30 V dc Power System was designed, built, and commissioned at Fermilab for testing Superconducting High Field Magnets. This system has been successfully supporting operations at the Fermilab Magnet Test Facility since April 2002. It is based on six commercial 150 kW Power Energy Industries power supply modules and the following in-house modules: six 720 Hz filters, two 15 kA/1kV dc solid-state dump switch, and a 3 MJ/30 kA/1 kV dc dump resistor. Additional inhouse electronic components were designed and built to provide precise current regulation and distribution of current and current rate of change. An industrial-type Programmable Logic Controller system was used to provide equipment interlocks and monitoring. This paper summarizes studies on the influence of characteristics of this new power system--such as ripple current--on the performance of High Field Superconducting magnets.

Carcagno, R.; Feher, S.; Garvey, J.; Jaskierny, W.; Lamm, M.; Makulski, A.; Orris, D.F.; Pfeffer, H.; Tartaglia, M.; Tompkins, J.; Wolff, D.; /Fermilab

2004-12-01

389

MULTI-TUBE POWER LEADS TOWER FOR BEPCII IR MAGNETS.  

SciTech Connect

A power lead tower containing the multi-tube power leads is designed and under fabrication for the superconducting IR quadrupole magnets in the Beijing Electron Position Collider Upgrade (BEPCII). The lead tower consists of six pairs of gas-cooled leads for seven superconducting coils at various operating currents. The power lead is designed in a modular fashion, which can be easily applied to suit different operating current. The end copper block of the tube lead has a large cold mass that provide a large time constant in case of cooling flow interruption. A novel cryogenic electrical isolator is used for the leads.

JIA,L.X.; ZHANG,X.B.; WANG,L.; WANG,T.H.; YAO,Z.L.

2004-05-11

390

Cooling through heat pumps powered by a combustion engine for natural gas  

NASA Astrophysics Data System (ADS)

The heat pump can be used both for heating and hot water in winter, but in the case of reversible heat pumps also air-conditioning in summer. Currently, air conditioners are becoming standard equipment for residential and industrial buildings. Heating and cooling occurs separately in many cases, ie that for the purpose of heating is used a separate heat source and for the cooling production other source of cold with own equipment and distribution systems. The heat pump is one device that can heat and cool often at a much lower price. This article deals with the research parameters of the gas heat pump in cooling mode.

Janovcová, Martina; Janda?ka, Jozef; Kiš, Roman

2014-08-01

391

Superconducting levitating bearing  

NASA Technical Reports Server (NTRS)

A superconducting bearing assembly includes a coil field source that may be superconducting and a superconducting structure. The coil field source assembly and superconducting structure are positioned so as to enable relative rotary movement therebetween. The structure and coil field source are brought to a supercooled temperature before a power supply induces a current in the coil field source. A Meissner-like effect is thereby obtained and little or no penetration of the field lines is seen in the superconducting structure. Also, the field that can be obtained from the superconducting coil is 2-8 times higher than that of permanent magnets. Since the magnetic pressure is proportioned to the square of the field, magnetic pressures from 4 to 64 times higher are achieved.

Moon, Francis C. (Inventor)

1996-01-01

392

Modeling of a 22.9 kV 50 MVA superconducting power cable based on PSCAD/EMTDC for application to the Icheon substation in Korea  

NASA Astrophysics Data System (ADS)

Two projects for high temperature superconducting (HTS) power cable have been carried out in Korea since 2001. One of them is a HTS cable project in DAPAS (Development of Advanced Power system by Applied Superconductivity technologies) program funded by the Ministry of Education, Science and Technology. In this project, LS Cable Ltd. (LSC) and Korea Electrotechnology Research Institute (KERI) jointly developed a 22.9 kV, 50 MVA, 3 phase, 100 m HTS cable using first generation (1G) HTS wire in 2006. The HTS cable system has been tested in a power test center of Korea Electric Power Corporation (KEPCO). LSC and KEPCO have been developing a 22.9 kV, 50 MVA, 3 phase, 500 m HTS cable system using second generation (2G) HTS wire since 2008, based on the technology of the DAPAS project. This project is called as GENI (Green Superconducting Electric Power Network at the Icheon Substation) project. The target of GENI project is to install and operate the HTS cable system in the Icheon substation located in near Seoul. In order to analyze the Icheon substation power system employing the HTS cable, an analysis model of the HTS cable is necessary. This paper describes the development of an analysis model for the 22.9 kV, 50 MVA HTS cable that will be applied to the Icheon substation in Korea.

Lee, S.; Yoon, J.; Lee, B.; Yang, B.

2011-11-01

393

Weight and power considerations for the design of a cryogenically cooled HTS electronic system  

Microsoft Academic Search

Much progress has been reported on the fabrication of high temperature superconducting (HTS) electronic devices, circuits and systems. In some of these reports, comparisons have been made between the electrical behavior of HTS components and their “equivalent” semiconductor counterparts. Unfortunately, in almost all cases, the comparisons have been made at the device or circuit level. In an operational system, the

M Nisenoff

1996-01-01

394

Impact of drought on U.S. steam electric power plant cooling water intakes and related water resource management issues.  

SciTech Connect

This report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) Existing Plants Research Program, which has an energy-water research effort that focuses on water use at power plants. This study complements their overall research effort by evaluating water availability at power plants under drought conditions. While there are a number of competing demands on water uses, particularly during drought conditions, this report focuses solely on impacts to the U.S. steam electric power plant fleet. Included are both fossil-fuel and nuclear power plants. One plant examined also uses biomass as a fuel. The purpose of this project is to estimate the impact on generation capacity of a drop in water level at U.S. steam electric power plants due to climatic or other conditions. While, as indicated above, the temperature of the water can impact decisions to halt or curtail power plant operations, this report specifically examines impacts as a result of a drop in water levels below power plant submerged cooling water intakes. Impacts due to the combined effects of excessive temperatures of the returned cooling water and elevated temperatures of receiving waters (due to high ambient temperatures associated with drought) may be examined in a subsequent study. For this study, the sources of cooling water used by the U.S. steam electric power plant fleet were examined. This effort entailed development of a database of power plants and cooling water intake locations and depths for those plants that use surface water as a source of cooling water. Development of the database and its general characteristics are described in Chapter 2 of this report. Examination of the database gives an indication of how low water levels can drop before cooling water intakes cease to function. Water level drops are evaluated against a number of different power plant characteristics, such as the nature of the water source (river vs. lake or reservoir) and type of plant (nuclear vs. fossil fuel). This is accomplished in Chapter 3. In Chapter 4, the nature of any compacts or agreements that give priority to users (i.e., which users must stop withdrawing water first) is examined. This is examined on a regional or watershed basis, specifically for western water rights, and also as a function of federal and state water management programs. Chapter 5 presents the findings and conclusions of this study. In addition to the above, a related intent of this study is to conduct preliminary modeling of how lowered surface water levels could affect generating capacity and other factors at different regional power plants. If utility managers are forced to take some units out of service or reduce plant outputs, the fuel mix at the remaining plants and the resulting carbon dioxide emissions may change. Electricity costs and other factors may also be impacted. Argonne has conducted some modeling based on the information presented in the database described in Chapter 2 of this report. A separate report of the modeling effort has been prepared (Poch et al. 2009). In addition to the U.S. steam electric power plant fleet, this modeling also includes an evaluation of power production of hydroelectric facilities. The focus of this modeling is on those power plants located in the western United States.

Kimmell, T. A.; Veil, J. A.; Environmental Science Division

2009-04-03

395

COOLING WATER ISSUES AND OPPORTUNITIES AT U.S. NUCLEAR POWER PLANTS  

Microsoft Academic Search

This report has been prepared for the Department of Energy, Office of Nuclear Energy (DOE-NE), for the purpose of providing a status report on the challenges and opportunities facing the U.S. commercial nuclear energy industry in the area of plant cooling water supply. The report was prompted in part by recent Second Circuit and Supreme Court decisions regarding cooling water

Gary Vine

2010-01-01

396

Evaluation of distributed gas cooling of pressurized PAFC for utility power generation  

NASA Technical Reports Server (NTRS)

A proof-of-concept test for a gas-cooled pressurized phosphoric acid fuel cell is described. After initial feasibility studies in short stacks, two 10 kW stacks are tested. Progress includes: (1) completion of design of the test stations with a recirculating gas cooling loop; (2) atmospheric testing of the baseline stack.

Farooque, M.; Hooper, M.; Maru, H.

1981-01-01

397

Evaluation of distributed gas cooling of pressurized PAFC for utility power generation  

NASA Astrophysics Data System (ADS)

A proof-of-concept test for a gas-cooled pressurized phosphoric acid fuel cell is described. After initial feasibility studies in short stacks, two 10 kW stacks are tested. Progress includes: (1) completion of design of the test stations with a recirculating gas cooling loop; (2) atmospheric testing of the baseline stack.

Farooque, M.; Hooper, M.; Maru, H.

1981-03-01

398

Evaluation of distributed gas cooling of pressurized PAFC for utility power generation  

NASA Astrophysics Data System (ADS)

A proof-of-concept test of a gas cooled pressurized phosphoric acid fuel cell (PAFC) is provided. Significant progress includes: design of subsystem components for the recirculation loop; fluid dynamic analyses of DIGAS cooling; and seal effectiveness testing of the baseline stack.

Ahmad, J.; Farooque, M.; Hooper, M.; Maru, H.

1980-12-01

399

Improved Performance of an Air Cooled Condenser (ACC) Using SPX Wind Guide Technology at Coal-Based Thermoelectric Power Plants  

SciTech Connect

This project added a new airflow enhancement technology to an existing ACC cooling process at a selected coal power plant. Airflow parameters and efficiency improvement for the main plant cooling process using the applied technology were determined and compared with the capabilities of existing systems. The project required significant planning and pre-test execution in order to reach the required Air Cooled Condenser system configuration for evaluation. A host Power Plant ACC system had to be identified, agreement finalized, and addition of the SPX ACC Wind Guide Technology completed on that site. Design of the modification, along with procurement, fabrication, instrumentation, and installation of the new airflow enhancement technology were executed. Baseline and post-modification cooling system data was collected and evaluated. The improvement of ACC thermal performance after SPX wind guide installation was clear. Testing of the improvement indicates there is a 5% improvement in heat transfer coefficient in high wind conditions and 1% improvement at low wind speed. The benefit increased with increasing wind speed. This project was completed on schedule and within budget.

Ken Mortensen

2010-12-31

400

Performance and cost of wet and dry cooling systems for pulverized coal power plants with and without carbon capture and storage  

Microsoft Academic Search

Thermoelectric power plants require significant quantities of water, primarily for the purpose of cooling. Water also is becoming critically important for low-carbon power generation. To reduce greenhouse gas emissions from pulverized coal (PC) power plants, post-combustion carbon capture and storage (CCS) systems are receiving considerable attention. However, current CO2 capture systems require a significant amount of cooling. This paper evaluates

Haibo Zhai; Edward S. Rubin

2010-01-01

401

USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES  

SciTech Connect

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Produced water is generated nationally as a byproduct of oil and gas production. Seven states generate 90 percent of the produced water in the continental US. About 37 percent of the sources documented in the US Geological Survey's (USGS) Produced Waters Database have a TDS of less than 30,000 mg/l. This is significant because produced water treatment for reuse in power plants was found to be very costly above 30,000 mg/l TDS. For the purposes of this report, produced water treatment was assessed using the technologies evaluated for the San Juan Generating Station (SJGS) in Deliverable 3, Treatment and Disposal Analysis. Also, a methodology was developed to readily estimate capital and operating costs for produced water treatment. Two examples are presented to show how the cost estimating methodology can be used to evaluate the cost of treatment of produced water at power plants close to oil and gas production.

Kent Zammit; Michael N. DiFilippo

2005-01-01

402

Potential of cryogenic liquids for future power equipment insulation in the medium high voltage range  

Microsoft Academic Search

Cryogenic liquids show a noteworthy impact on the concept of improved future power equipment with superconductors. Superconducting materials eliminate any Joule heating but are based on very low operating temperatures. A high overall current density in the equipment may be presupposed. Cooling however must be guaranteed by cryogenic liquids, i.e. liquid helium or liquid nitrogen, respectively. The cooling liquids are

J. Gerhold

2002-01-01

403

Development of a high-power water cooled beryllium target for use in accelerator-based boron neutron capture therapy.  

PubMed

In order for ABNCT (accelerator-based boron neutron capture therapy) to be successful, 10-16 kW or more must be dissipated from a target. Beryllium is well suited as a high-power target material. Beryllium has a thermal conductivity of 200 W/mK at 300 K which is comparable to aluminum, and it has one of the highest strength to weight ratios of any metal even at high temperatures (100 MPa at 600 degrees C). Submerged jet impingement cooling has been investigated as an effective means to remove averaged power densities on the order of 2 x 10(7) W/m2 with local power densities as high as 6 x 10(7) W/m2. Water velocities required to remove these power levels are in excess of 24 m/s with volumetric flow rates of nearly 100 GPM. Tests on a prototype target revealed that the heat transfer coefficient scaled as Re0.6. With jet-Reynolds numbers as high as 5.5 x 10(5) heat transfer coefficients of 2.6 x 10(5) W/m2K were achieved. With this type of cooling configuration 30 kW of power could be effectively removed from a beryllium target placed on the end of an accelerator. A beryllium target utilizing a proton beam of 3.7 MeV and cooled by submerged jet impingement could be used to deliver a dose of 13 RBE cGy/min mA to a tumor at a depth of 4 cm. With a beam power of 30 kW, 1500 cGy could be delivered in 14.2 min. PMID:9800705

Blackburn, B W; Yanch, J C; Klinkowstein, R E

1998-10-01

404

Aerospace applications of high temperature superconductivity  

NASA Technical Reports Server (NTRS)

Space application of high temperature superconducting (HTS) materials may occur before most terrestrial applications because of the passive cooling possibilities in space and because of the economic feasibility of introducing an expensive new technology which has a significant system benefit in space. NASA Lewis Research Center has an ongoing program to develop space technology capitalizing on the potential benefit of HTS materials. The applications being pursued include space communications, power and propulsion systems, and magnetic bearings. In addition, NASA Lewis is pursuing materials research to improve the performance of HTS materials for space applications.

Heinen, V. O.; Connolly, D. J.

1991-01-01

405

FEASIBILITY OF RECOVERING USEFUL SALTS FROM IRRIGATION WASTEWATER CONCENTRATES PRODUCED BY POWER PLANT COOLING  

EPA Science Inventory

The report evaluates the feasibility of a novel energy-conserving way to recover useful salts (sodium sulfate and calcium sulfate) from concentrated brines by evaporation/crystallization. The concentrated brines examined were cooling tower blowdown from agricultural wastewater an...

406

Cryogenic operation of UHF power static induction transistors  

Microsoft Academic Search

Results are described of recent experiments with high power surface-gate silicon static induction transistors (SGSITs) operated at and near the temperature of liquid nitrogen, which would be employed in cooling RF power systems for the entire electronics system in high Tc superconducting technologies. Following a discussion of SIT operation, the dc current-voltage characteristics of a test SGSIT are examined. The

Robert J. Regan; Scott J. Butler; Mehdy Abdollahian; Emel Bulat

1989-01-01

407

Development of high temperature superconducting current feeders for a large-scale superconducting experimental fusion system  

Microsoft Academic Search

The National Institute for Fusion Science (NIFS), in collaboration with universities and laboratories in Japan, the Forschungszentrum Karlsruhe (FZK) and the Max-Planck Institut fur Plasma Physik (IPP) in Germany, is planning to develop high temperature superconducting (HTS) current feeders for large-scale superconducting coils. Two programs are being progressed: one is a current feedthrough for superfluid helium (He II) cooled superconducting

T. Mito; K. Takahata; R. Heller; A. Iwamoto; R. Maekawa; H. Tamura; Y. Yamada; K. Tachikawa; K. Maehata; K. Ishibashi; G. Friesinger; M. Tasca; A. Nishimura; S. Yamada; S. Imagawa; N. Yanagi; H. Chikaraishi; S. Hamaguchi; M. Takeo; T. Shintomi; T. Satow; O. Motojima

2001-01-01

408

The superconducting magnet of AMS-02  

NASA Astrophysics Data System (ADS)

The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to search for anti-matter, dark matter and the origin of cosmic rays in space. The detector will be installed on the International Space Station (ISS). The planned duration of the experiment is 3 years. The magnetic dipole field is achieved by an arrangement of 14 superconducting coils. The magnet system consists of a pair of large Helmholtz coils together with two series of six racetrack coils, circumferentially distributed between them. This arrangement was mainly chosen to minimize the stray field outside of the magnet. It generates a magnetic field of 0.87 T in the center of the magnet with a bending power of 0.78 Tm 2. All superconducting coils are indirectly cooled by pressurized superfluid helium at 1.8 K. This cooling loop is thermally connected with a 2500 l vessel for superfluid helium which serves as a cold reservoir. In order to ensure the 3 year endurance without refilling, the magnet design was optimized with respect to very low heat losses. This paper describes the main features of the AMS superconducting magnet and the principle concept of the cryogenic system.

Blau, B.; Harrison, S. M.; Hofer, H.; Milward, S. R.; Ross, J. S. H.; Ting, S. C. C.; Ulbricht, J.; Viertel, G.

409

Site dependent factors affecting the economic feasibility of solar powered absorption cooling  

NASA Technical Reports Server (NTRS)

A procedure was developed to evaluate the cost effectiveness of combining an absorption cycle chiller with a solar energy system. A basic assumption of the procedure is that a solar energy system exists for meeting the heating load of the building, and that the building must be cooled. The decision to be made is to either cool the building with a conventional vapor compression cycle chiller or to use the existing solar energy system to provide a heat input to the absorption chiller. Two methods of meeting the cooling load not supplied by solar energy were considered. In the first method, heat is supplied to the absorption chiller by a boiler using fossil fuel. In the second method, the load not met by solar energy is net by a conventional vapor compression chiller. In addition, the procedure can consider waste heat as another form of auxiliary energy. Commercial applications of solar cooling with an absorption chiller were found to be more cost effective than the residential applications. In general, it was found that the larger the chiller, the more economically feasible it would be. Also, it was found that a conventional vapor compression chiller is a viable alternative for the auxiliary cooling source, especially for the larger chillers. The results of the analysis gives a relative rating of the sites considered as to their economic feasibility of solar cooling.

Bartlett, J. C.

1978-01-01

410

Feasibility study of a superconducting motor for electrical helicopter propulsion  

NASA Astrophysics Data System (ADS)

During the past decades, superconducting electrical machines have become more suitable to replace conventional iron based designs, because of their lower weight and higher torque density. These properties make them good candidates for use in More Electric Aircraft (MEA). Especially helicopter propulsion systems could benefit from the increased performance. This paper describes the feasibility study of a superconducting motor to be used for helicopter propulsion as part of a More Electric Aircraft (MEA). For this, the armature, field windings and cryostat are designed, aiming at meeting the difficult specifications. Since superconductors have virtually no electrical resistance when cooled down below a certain critical temperature, they can be used to build high field and low weight coils for electrical machines. Especially the possibility to not use iron can make the superconducting motor lighter with a higher power density compared with conventional Permanent Magnet (PM) motors.

Simons, C. A. B. A. E.; Sanabria-Walter, C.; Polinder, H.

2014-05-01

411

Superconducting light generator for large offshore wind turbines  

NASA Astrophysics Data System (ADS)

Offshore wind market demands higher power rate and reliable turbines in order to optimize capital and operational cost. These requests are difficult to overcome with conventional generator technologies due to a significant weight and cost increase with the scaling up. Thus superconducting materials appears as a prominent solution for wind generators, based on their capacity to held high current densities with very small losses, which permits to efficiently replace copper conductors mainly in the rotor field coils. However the state-of-the-art superconducting generator concepts still seem to be expensive and technically challenging for the marine environment. This paper describes a 10 MW class novel direct drive superconducting generator, based on MgB2 wires and a modular cryogen free cooling system, which has been specifically designed for the offshore wind industry needs.

Sanz, S.; Arlaban, T.; Manzanas, R.; Tropeano, M.; Funke, R.; Ková?, P.; Yang, Y.; Neumann, H.; Mondesert, B.

2014-05-01

412

Offshore Floating Wind Turbine-driven Deep Sea Water Pumping for Combined Electrical Power and District Cooling  

NASA Astrophysics Data System (ADS)

A new concept utilising floating wind turbines to exploit the low temperatures of deep sea water for space cooling in buildings is presented. The approach is based on offshore hydraulic wind turbines pumping pressurised deep sea water to a centralised plant consisting of a hydro-electric power system coupled to a large-scale sea water-cooled air conditioning (AC) unit of an urban district cooling network. In order to investigate the potential advantages of this new concept over conventional technologies, a simplified model for performance simulation of a vapour compression AC unit was applied independently to three different systems, with the AC unit operating with (1) a constant flow of sea surface water, (2) a constant flow of sea water consisting of a mixture of surface sea water and deep sea water delivered by a single offshore hydraulic wind turbine and (3) an intermittent flow of deep sea water pumped by a single offshore hydraulic wind turbine. The analysis was based on one year of wind and ambient temperature data for the Central Mediterranean that is known for its deep waters, warm climate and relatively low wind speeds. The study confirmed that while the present concept is less efficient than conventional turbines utilising grid-connected electrical generators, a significant portion of the losses associated with the hydraulic transmission through the pipeline are offset by the extraction of cool deep sea water which reduces the electricity consumption of urban air-conditioning units.

Sant, T.; Buhagiar, D.; Farrugia, R. N.

2014-06-01

413

Helical Muon Beam Cooling Channel Engineering Design  

SciTech Connect

The Helical Cooling Channel (HCC), a novel technique for six-dimensional (6D) ionization cooling of muon beams, has shown considerable promise based on analytic and simulation studies. However, the implementation of this revolutionary method of muon cooling requires new techniques for the integration of hydrogen-pressurized, high-power RF cavities into the low-temperature superconducting magnets of the HCC. We present the progress toward a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb{sub 3}Sn based HCC test section. We include discussions on the pressure and thermal barriers needed within the cryostat to maintain operation of the magnet at 4.2 K while operating the RF and energy absorber at a higher temperature. Additionally, we include progress on the Nb{sub 3}Sn helical solenoid design.

Kashikhin, V.S.; Lopes, M.L.; Romanov, G.V.; Tartaglia, M.A.; Yonehara, K.; Yu, M.; Zlobin, A.V.; /Fermilab; Flanagan, G.; Johnson, R.P.; Kazakevich, G.M.; Marhauser, F.; /MUONS Inc., Batavia

2012-05-01

414

High-power operation of 1cm laser diode bars on funryu heat sink cooled by fluorinated-refrigerant  

NASA Astrophysics Data System (ADS)

We investigated the properties of fluorinated refrigerants for high-power laser diode bars mounted on a funryu heat sink. The thermal conductivity of fluorinated refrigerants is about ten times lower than that of water, but they are less corrosive to funryu heat sinks. Using 3M's "Fluorinet" FC77 and "Novec" HFE-7300 and comparing them with water as refrigerants, we developed a new fluorinated refrigerant cooling device that is suitable for removing heat from highpower LDs and LD modules. This device achieved CW light-output power from a 1-cm LD bar equivalent to that for a cooling device using ion-exchange water. With HFE-7300 as the refrigerant, we achieved over 100 W of output power at a drive current of CW 120 A and over 1.5 kW for a stacked-LD module operated at a constant current of 55 A in continuous-wave (CW) mode. High-power LD bars subjected to lifetime testing under these conditions have been successfully running for over 15,000 consecutive hours.

Oishi, Satoru; Miyajima, Hirofumi; Suzuki, Noriyasu; Natsume, Tomoyuki; Fujita, Toru; Nishida, Koji; Kurino, Hironobu; Okamoto, Ryusuke; Kageyama, Nobuto; Suzuki, Nobutaka; Uchiyama, Takayuki; Kan, Hirofumi

2009-02-01

415

Technical and economic assessment of the use of ammonia expanders for energy recovery in air-cooled power plants  

SciTech Connect

Binary cycle power plants have been the subject of much discussion among engineers and scientists for nearly 100 years. Current economic and environmental concerns have stimulated new interest and research. Ammonia has been recommended by other studies as the leading contender for use as simply the heat rejection medium in an air-cooled power plant. This study investigates the technical feasibility and economic potential of including an expander in the heat rejection system of an air-cooled power plant. The expander would be used during certain parts of the year to increase the total output of the power plant. Five different plant locations (Miami, San Francisco, Bakersfield, Chicago, Anchorage) were investigated to show the effect which climate has on the economic potential of this ammonia bottoming cycle. The study shows that the expected energy costs for the bottoming cycle only will be less than 50 mills/kWh for any of the five plant locations. This cost assumes that an ammonia phase-change heat rejection system is already a part of the existing plant. The colder climates of Chicago and Anchorage demonstrate an even smaller energy cost of less than 15 mills/kWh. Further investigation of the concept is merited to substantiate these costs and determine the needed technology.

Hauser, S.G.; Hane, G.J.; Johnson, B.M.

1982-07-01

416

Serious pitting hazard in the raft river 5MW(e) Geothermal Power Plant isobutane cooling loop  

SciTech Connect

The 5MW(e) Dual Boiling Cycle Geothermal Power Plant, hence referred to as the Raft River plant, is being developed for DOE by EG and G, Inc., Idaho Falls, Idaho. This pilot power plant is of the binary concept and utilizes isobutane as the working second fluid. The plant will demonstrate the feasibility of power generation from an intermediate temperature ({approx} 290 F) resource. The plant is schematically diagrammed in Figure 1. During the final design phase and after the major components were specified to be made of carbon steel, and ordered, various conditions forced the power plant design to switch from surface water to geothermal fluid for the condenser cooling loop make-up water. Because the geothermal fluid contains significant concentrations of chlorides and sulfates, about 1000 ppm and 65 ppm respectively, aeration in the cooling tower causes this water to become extremely aggressive, especially in the pitting of carbon steel components. Although essentially all of the condenser cooling loop materials are carbon steel, the isobutane condenser and turbine lube oil cooler are the most vulnerable. These components are tubed with carbon steel tubes of 0.085 and 0.075 inch wall thickness. These two components are extremely leak critical heat exchangers. For example, even a single pit perforation in the isobutane condenser can cause plant shutdown through loss of isobutane. Such a leak also poses an explosion or fire hazard. As isobutane pressure falls, the incursion of cooling water into the isobutane loop could occur, causing damage to anhydrous service seals. Under a DOE contract for geothermal failure analysis, Radian Corporation has made a preliminary investigation of the pitting hazard presented by the aggressive cooling fluid and the corrosion inhibition treatment that has thus far been proposed. This report documents Radian's understanding of the present situation and the results of its investigation on possible mitigation of this hazard. Finally, various conclusions and recommendations are made that may, if pursued, lead to a satisfactory solution that will avert a certain early prolonged plant shutdown due to failure of the thin walled isobutane and turbine lube oil cooler tubes.

Ellis, Peter F.

1980-02-25

417

Superconducting Magnets in High-Energy Physics: Large-scale magnets that dissipate no electrical power are under construction for high-energy physics research.  

PubMed

The promise of superconductivity making possible large magnets that dissipate no power is now being realized. Most of the early difficulties have been overcome; hence it is now a straight-forward engineering problem to design and build a large stable supermagnet. The application of such magnets to research in high-energy physics can be expected to grow rapidly in the next few years. PMID:17794314

Derrick, M

1967-10-20

418

Use of Air2Air Technology to Recover Fresh-Water from the Normal Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants  

SciTech Connect

This program was undertaken to build and operate the first Air2Air{trademark} Water Conservation Cooling Tower at a power plant, giving a validated basis and capability for water conservation by this method. Air2Air{trademark} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10%-25% annually, depending on the cooling tower location (climate).

Ken Mortensen

2009-06-30

419

Evaluation of distributed gas cooling of pressurized PAFC for utility power generation  

NASA Astrophysics Data System (ADS)

Two short stacks were pressure tested at 446 kPa (4.4 atm.) and the pressure gains were more than the theoretically predicted gains. Temperature profiles were observed to be independent of operating pressure. The pressure drop was found to be inversely proportional to operating pressure as expected. Continuous pressurized operation of a stack for 1000 hours verified the compatability of the fuel cell component design. A simple pressurization procedure was also developed. Six separate designs, covering two gas cooling schemes (DIGAS and separated) and two cooling channel geometries (straight through and treed), were analysed on the net voltage output basis. Separated cooling with 5 cells per cooler was recognized to be the best among the designs considered.

Farooque, M.; Maru, H.; Skok, A.

1981-05-01

420

Evaluation of distributed gas cooling of pressurized PAFC for utility power generation  

NASA Technical Reports Server (NTRS)

Two short stacks were pressure tested at 446 kPa (4.4 atm.) and the pressure gains were more than the theoretically predicted gains. Temperature profiles were observed to be independent of operating pressure. The pressure drop was found to be inversely proportional to operating pressure as expected. Continuous pressurized operation of a stack for 1000 hours verified the compatability of the fuel cell component design. A simple pressurization procedure was also developed. Six separate designs, covering two gas cooling schemes (DIGAS and separated) and two cooling channel geometries (straight through and treed), were analysed on the net voltage output basis. Separated cooling with 5 cells per cooler was recognized to be the best among the designs considered.

Farooque, M.; Maru, H.; Skok, A.

1981-01-01

421

Superconducting magnet  

DOEpatents

A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

Satti, John A. (Naperville, IL)

1980-01-01

422

Self-cooling mono-container fuel cell generators and power plants using an array of such generators  

DOEpatents

A mono-container fuel cell generator contains a layer of interior insulation, a layer of exterior insulation and a single housing between the insulation layers, where fuel cells, containing electrodes and electrolyte, are surrounded by the interior insulation in the interior of the generator, and the generator is capable of operating at temperatures over about 650 C, where the combination of interior and exterior insulation layers have the ability to control the temperature in the housing below the degradation temperature of the housing material. The housing can also contain integral cooling ducts, and a plurality of these generators can be positioned next to each other to provide a power block array with interior cooling. 7 figs.

Gillett, J.E.; Dederer, J.T.; Zafred, P.R.

1998-05-12

423

Self-cooling mono-container fuel cell generators and power plants using an array of such generators  

DOEpatents

A mono-container fuel cell generator (10) contains a layer of interior insulation (14), a layer of exterior insulation (16) and a single housing (20) between the insulation layers, where fuel cells, containing electrodes and electrolyte, are surrounded by the interior insulation (14) in the interior (12) of the generator, and the generator is capable of operating at temperatures over about 650.degree. C., where the combination of interior and exterior insulation layers have the ability to control the temperature in the housing (20) below the degradation temperature of the housing material. The housing can also contain integral cooling ducts, and a plurality of these generators can be positioned next to each other to provide a power block array with interior cooling.

Gillett, James E. (Greensburg, PA); Dederer, Jeffrey T. (Valencia, PA); Zafred, Paolo R. (Pittsburgh, PA)

1998-01-01

424

Economic analysis of wind-powered refrigeration cooling/water-heating systems in food processing. Final report  

SciTech Connect

Potential applications of wind energy include not only large central turbines that can be utilized by utilities, but also dispersed systems for farms and other applications. The US Departments of Energy (DOE) and Agriculture (USDA) currently are establishing the feasibility of wind energy use in applications where the energy can be used as available, or stored in a simple form. These applications include production of hot water for rural sanitation, heating and cooling of rural structures and products, drying agricultural products, and irrigation. This study, funded by USDA, analyzed the economic feasibility of wind power in refrigeration cooling and water heating systems in food processing plants. Types of plants included were meat and poultry, dairy, fruit and vegetable, and aquaculture.

Garling, W.S.; Harper, M.R.; Merchant-Geuder, L.; Welch, M.

1980-03-01

425

Thermal and dynamic analysis of the RING (Radiatively-cooled, Inertially-driven Nuclear Generator) power system radiator  

SciTech Connect

The nuclear option for a space-based power system appears most suitable for missions that require long-term, sustained operation at power levels above 100 kWe. Systems currently available operate at relatively low thermal efficiencies (6--10%). Thus, a 100 kWe system must discharge nearly 2 MWth of waste heat through the comparatively inefficient process of radiative cooling. The impact of the resultant radiator assembly size on overall power system weight is significant, and has led to proposals for radiators with potentially higher efficiencies. Examples include the: liquid droplet radiator; fabric radiator; bubble membrane radiator; rotating film radiator; and dust radiator. 14 refs., 2 figs., 2 tabs.

Apley, W.J.; Babb, A.L.

1989-01-01

426

Power systems  

NASA Astrophysics Data System (ADS)

Significant events in current, prototype, and experimental utility power generating systems in 1981 are reviewed. The acceleration of licensing and the renewal of plans for reprocessing of fuel for nuclear power plants are discussed, including the rise of French reactor-produced electricity to over 40% of the country's electrical output. A 4.5 MW fuel cell neared completion in New York City, while three 2.5 MW NASA-designed windpowered generators began producing power in the state of Washington. Static bar compensators, nonflammable-liquid cooled power transformers, and ZnO surge arrestors were used by utilities for the first time, and the integration of a coal gasifier-combined cycle power plant approached the planning phase. An MHD generator was run for 1000 hours and produced 50-60 kWe, while a 20 MVA superconducting generator was readied for testing.

Kaplan, G.

1982-01-01

427

High-Temperature Superconductive Cabling Investigated for Space Solar Power Satellites  

NASA Technical Reports Server (NTRS)

NASA has been directed by Congress to take a fresh look at the Space Solar Power (SSP) concept that was studied by the Department of Energy and NASA about 20 years ago. To summarize, the concept involves (1) collecting solar energy and converting it to electrical energy via photovoltaic arrays on satellites in Earth orbit, (2) conducting the electricity to the microwave transmitting portion of the satellite, and (3) transmitting the power via microwave transmitters (or possibly via lasers) to ground power station antennas located on the surface of the Earth. One Sun Tower SSP satellite concept is illustrated here. This figure shows many photovoltaic arrays attached to a "backbone" that conducts electricity down to a wireless transmitter, which is pointed toward the Earth. Other variations on this concept use multiple backbones to reduce the overall length of the satellite structure. In addition, non-Sun-Tower concepts are being considered. The objective of the work reported here was to determine the benefits to the SSP concept of using high-temperature superconductors (HTS) to conduct the electricity from the photovoltaic arrays to the wireless power transmitters. Possible benefits are, for example, reduced mass, improved efficiency, and improved reliability. Dr. James Powell of Plus Ultra Technologies, Inc., of Stony Brook, New York, is conducting the study, and it is being managed by the NASA Glenn Research Center at Lewis Field via a task-order contract through Scientific Applications International Corp. (SAIC).

Tew, Roy C.; Juhasz, Albert J.

2000-01-01

428

Expanding the potential for saline formations : modeling carbon dioxide storage, water extraction and treatment for power plant cooling.  

SciTech Connect

The National Water, Energy and Carbon Sequestration simulation model (WECSsim) is being developed to address the question, 'Where in the current and future U.S. fossil fuel based electricity generation fleet are there opportunities to couple CO{sub 2} storage and extracted water use, and what are the economic and water demand-related impacts of these systems compared to traditional power systems?' The WECSsim collaborative team initially applied this framework to a test case region in the San Juan Basin, New Mexico. Recently, the model has been expanded to incorporate the lower 48 states of the U.S. Significant effort has been spent characterizing locations throughout the U.S. where CO{sub 2} might be stored in saline formations including substantial data collection and analysis efforts to supplement the incomplete brine data offered in the NatCarb database. WECSsim calculates costs associated with CO{sub 2} capture and storage (CCS) for the power plant to saline formation combinations including parasitic energy costs of CO{sub 2} capture, CO{sub 2} pipelines, water treatment options, and the net benefit of water treatment for power plant cooling. Currently, the model can identify the least-cost deep saline formation CO{sub 2} storage option for any current or proposed coal or natural gas-fired power plant in the lower 48 states. Initial results suggest that additional, cumulative water withdrawals resulting from national scale CCS may range from 676 million gallons per day (MGD) to 30,155 MGD depending on the makeup power and cooling technologies being utilized. These demands represent 0.20% to 8.7% of the U.S. total fresh water withdrawals in the year 2000, respectively. These regional and ultimately nation-wide, bottom-up scenarios coupling power plants and saline formations throughout the U.S. can be used to support state or national energy development plans and strategies.

Not Available

2011-04-01

429

Tritium control modelling for a helium cooled lithium–lead blanket of a fusion power reactor  

Microsoft Academic Search

In this paper, we present computations linking the tritium release rate to the characteristics of lithium–lead and helium cooling circuits. Impacting component performances are evaluated such as tritium permeation towards the He coolant in the blanket modules, lithium–lead circulation rate, tritium extraction unit efficiency, tritium permeation in steam generator, helium coolant leak rate, helium purification unit maximum flow rate and

W. Farabolini; A. Ciampichetti; F. Dabbene; M. A. Fütterer; L. Giancarli; G. Laffont; A. Li Puma; S. Raboin; Y. Poitevin; I. Ricapito; P. Sardain

2006-01-01

430

REPRODUCTION AND DISTRIBUTION OF FISHES IN A COOLING LAKE: WISCONSIN POWER PLANT IMPACT STUDY  

EPA Science Inventory

Spatial and temporal patterns during reproduction and early life history of fishes were studied in a manmade cooling lake. Lake Columbia, impounded in 1974, near Portage, Wisconsin, has an area of 190 ha, a mean depth of 2.1 m, and a 15C temperature gradient derived from the ther...

431

Dry cooling design characteristics of a large power plant. [330MW Wyodak Station in NE Wyoming  

Microsoft Academic Search

The new Wyodak Station in the northeast corner of Wyoming, now under construction and scheduled for operation by May 1, 1978, is rated at 330 MW and will be the largest air-cooled unit in the world. The shortage of water in the area is so severe that extreme measures were required to obtain water for other plant uses, e.g., steam

R. C. Norton; W. J. Westre; G. L. Larsen

1975-01-01

432

Intracavity-enhanced laser cooling of solids using high power VECSELs at 1020 nm  

NASA Astrophysics Data System (ADS)

Laser cooling of solids to 148 K has been demonstrated in a Yb:YLF crystal using intracavity absorption enhancement in an InGaAs MQW VECSEL at 1020 nm. This is the lowest temperature achieved in the intracavity geometry to date and presents a significant advancement towards an all-solid-state compact cryocooler.

Sheik-Bahae, Mansoor; Ghasemkhani, Mohammad; Albrecht, Alexander R.; Seletskiy, Denis V.; Cederberg, Jeffrey G.; Melgaard, Seth D.

2013-02-01

433

An assessment of the use of direct contact condensers with wet cooling systems for utility steam power plants  

SciTech Connect

Potential use of a direct contact condenser for steam recovery at the turbine exhaust of a utility power plant using a wet cooling system is investigated. To maintain condensate separate from the cooling water, a bank of plate heat exchangers is used. In a case study for a nominal 130-MW steam power plant, two heat rejection systems, one using a conventional surface condenser and another using a direct contact condenser together with a set of plate heat exchangers are compared on the basis of their performance, operation and maintenance, and system economics. Despite a higher initial cost for the direct contact system, the advantages it offers suggests that this system is viable both technically and economically. Key to the improvements the direct contact system offers is a higher equivalent availability for the power system. Reduction of dissolved oxygen and other metallic ions in the condensate, reduced use of chemical scavengers and polishers, and potential elimination of a plant floor are also major benefits of this system. Drawbacks include added plant components and higher initial cost. The potential for long-term cost reduction for the direct contact system is also identified.

Bharathan, D.; Hoo, E. [National Renewable Energy Lab., Golden, CO (United States)] [National Renewable Energy Lab., Golden, CO (United States); D`Errico, P. [Stone and Webster Engineering Corp., Boston, MA (United States)] [Stone and Webster Engineering Corp., Boston, MA (United States)

1992-02-01

434

Higher-order-mode (HOM) power in elliptical superconducting cavities for intense pulsed proton accelerators  

Microsoft Academic Search

In linacs for intense pulsed proton accelerators, the beam has a multiple time-structure, and each beam time-structure generates resonance. When a higher-order mode (HOM) is near these resonance frequencies, the induced voltage could be large and accordingly the resulting HOM power, too. In order to understand the effects of a complex beam time-structure on the mode excitations and the resulting

Sang-ho Kim; Marc Doleans; Dong-o Jeon; Ronald Sundelin

2002-01-01

435

High Power Intermodulation Measurements up to 30 W of High Temperature Superconducting Filters  

NASA Technical Reports Server (NTRS)

We have demonstrated a high power intermodulation measurement set-up capable of delivering 30 W in each of two fundamental tones. For closely spaced frequencies (less than 35 MHz), the dynamic range of the measurement is limited by the nonlinear performance of the mixer in the front end of the HP71210C spectrum analyzer. A tunable TE(sub 011) mode copper cavity was fabricated in which one of the endwalls could be adjusted shifting its resonant frequency between 5.7 and 6.6 GHz. Since the Q-value of this cavity is high, greater than 10(exp 4), and its bandwidth is small, less than 1 MHz, it can be used to attenuate the two fundamental tones relative to one of the harmonic tones, which greatly enhances the dynamic range of the measurement. This set-up can be used to measure the two-tone intermodulation distortion of any passive microwave device, e.g. a HTS filter, a connector, a cable, etc., over a frequency range of 5.9 to 6.4 GHz and a power range of 0.1 to 30 W. The third order intercept (TOI) of a prototype HTS filter measured at powers up to 30 W was +81.3 dBm.

Wilker, Charles; Carter, Charles F., III; Shen, Zhi-Yuan

1999-01-01

436

Power conversion system design for supercritical carbon dioxide cooled indirect cycle nuclear reactors  

E-print Network

The supercritical carbon dioxide (S-CO?) cycle is a promising advanced power conversion cycle which couples nicely to many Generation IV nuclear reactors. This work investigates the power conversion system design and ...

Gibbs, Jonathan Paul

2008-01-01

437

Study on neutronic of very small Pb - Bi cooled no-onsite refueling nuclear power reactor (VSPINNOR)  

NASA Astrophysics Data System (ADS)

A conceptual design study on Very Small Pb-Bi No-Onsite Refueling Cooled Nuclear Reactor (VSPINNOR) with Uranium nitride fuel using MCNPX program has been performed. In this design the reactor core is divided into three regions with different enrichment. At the center of the core is laid fuel without enrichment (internal blanket). While for the outer region using fuel enrichment variations. VSPINNOR fast reactor was operated for 10 years without refueling. Neutronic analysis shows optimized result of VSPINNOR has a core of 50 cm radius and 100 cm height with 300 MWth thermal power output at 60% fuel fraction that can be operated 18 years without refueling or fuel shuffling.

Arianto, Fajar; Su'ud, Zaki; Zuhair

2014-09-01

438

Study on neutronic of very small Pb - Bi cooled no-onsite refueling nuclear power reactor (VSPINNOR)  

SciTech Connect

A conceptual design study on Very Small Pb-Bi No-Onsite Refueling Cooled Nuclear Reactor (VSPINNOR) with Uranium nitride fuel using MCNPX program has been performed. In this design the reactor core is divided into three regions with different enrichment. At the center of the core is laid fuel without enrichment (internal blanket). While for the outer region using fuel enrichment variations. VSPINNOR fast reactor was operated for 10 years without refueling. Neutronic analysis shows optimized result of VSPINNOR has a core of 50 cm radius and 100 cm height with 300 MWth thermal power output at 60% fuel fraction that can be operated 18 years without refueling or fuel shuffling.

Arianto, Fajar, E-mail: ariantofajar@gmail.com [Laboratory of Nuclear and Biophysics, Department of Physics, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132, Indonesia and Laboratory of Atom and Nuclear, Department of Physics, Diponegoro University, Jl. Prof. Soedarto, S.H., Tembala (Indonesia); Su'ud, Zaki, E-mail: szaki@fi.itba.c.id [Nuclear Physics and Biophysics Research Group, Faculty of Mathematics and Natural Science, Bandung Institute of Technology (Ganesha 10 Bandung, Indonesia) (Indonesia); Zuhair [Center for Reactor Technology and Nuclear Safety, National Nuclear Energy Agency, Kawasan Puspiptek, Gedung No. 80, Serpong, Tangerang 15310 (Indonesia)

2014-09-30

439

Short-circuit characteristics of non-inductive superconducting coil wound with stainless steel stabilized coated conductor in sub-cooled liquid nitrogen  

Microsoft Academic Search

This paper deals with the short-circuit characteristics, including current limiting and current distribution characteristics of non-inductive superconducting coil wound with stainless steel-stabilized coated conductor (CC). From the tests of current limiting characteristics, we concluded that:(1)stainless steel-stabilized CC is efficient in the reduction of the wires required and volume of bobbin. However, its current limitation was not as efficient due to

M. J. Kim; S. E. Yang; M. C. Ahn; D. K. Park; Y. Kim; Y. S. Yoon; T. K. Ko

2007-01-01

440

A Cool-down and Fault Study of a Long Length HTS Power Transmission Cable  

Microsoft Academic Search

High temperature superconductor (HTS) power transmission cables offer significant advantages in power density over conventional copper-based cables. Currently the US Department of Energy is funding the design, development, and demonstration of the first long length, transmission level voltage, cold dielectric, underground high temperature superconductor power cable. The cable is 620 meters long and is designed for permanent installation in the

J. Yuan; J. Maguire; A. Allais; F. Schmidt

2006-01-01

441

Electric and magnetic properties measurement and analysis of a conventional and a superconducting power transformer  

NASA Astrophysics Data System (ADS)

Power transformers based on High Temperature Superconductors (HTS) technology have revealed potential for several practical applications, offering economic, environmental and operational benefits. In this work, two 650 VA single-phase transformers prototypes were developed, tested and characterized: a conventional one, using copper windings, and another with the same primary copper winding, but with a secondary winding made of HTS BSCCO tape. The two prototypes were compared regarding magnetic properties, losses, electric parameters and efficiency, and the results are presented and interpreted. Also, several measures to determine AC critical current of the HTS tape were made. The results are compared with DC critical current for the same tape.

Figueira, P.; Pronto, A. G.; Vilhena, N.; Pina, J. M.

2014-05-01

442

Energy Efficiency Evaluation of Refrigeration Technologies in Combined Cooling, Heating and Power Systems  

E-print Network

power( ) for compression chiller. For this selection, extra electrical power ( ) will be consumed for the same quantity of cold energy ( ) production, and can be positive or negative value. hQ cQ 2 3 cQ 3 Two refrigeration modes are given by Fig...). hQ 1 cQ 3 1 w wRESR + ?= (3) hQ St eam turbine 2 Compr essi on chiller 3 cQSt eam Ret urn wat er Power Power Col d energy St eam h St eam chiller 1 Col d energy c Return water Power (a) (b) Fig 3 Two modes of steam utilization...

Zuo, Z.; Hu, W.

2006-01-01

443

Analysis of the solar powered\\/fuel assisted Rankine cycle cooling system. Phase 1: Revision  

Microsoft Academic Search

The subject of this analysis is a solar cooling system which consists of a conventional open-compressor chiller, driven by a novel hybrid steam Rankine cycle. Steam is generated by the use of solar energy collected at about 100C, and it is then superheated to about 600C in a fossil-fuel fired superheater. The steam drives a novel counter-rotating turbine, some of

N. Lior; K. Koai; H. Yeh

1985-01-01

444

A neutronic investigation of He-cooled liquid Li-breeder blankets for fusion power reactor  

Microsoft Academic Search

Configuration of a He-cooled liquid lithium blanket has been optimized in terms of the tritium breeding ratio (TBR) and the neutron shielding. For a model blanket, fundamental neutronic characteristics are analyzed with a Monte Carlo code. To improve the TBR, various neutron reflectors are compared, which are graphite, TiC and ZrH2, and the optimal application of the reflector is investigated,

Y. Kim; B. G. Hong; C. H. Kim

2005-01-01

445

Reproduction and distribution of fishes in a cooling lake: Wisconsin power plant impact study  

Microsoft Academic Search

Spatial and temporal patterns during reproduction and early-life history of fishes were studied in a manmade cooling lake. Lake Columbia, impounded in 1974, near Portage, Wisconsin, has an area of 190 ha, a mean depth of 2.1 m, and a 15C temperature gradient derived from the thermal effluent of a 527-MW fossil-fueled generating station that began operating in 1975. The

D. W. Rondorf; J. F. Kitchell

1985-01-01

446

Asbestos in cooling-tower waters. Final report. [Source, hazards, and recommendations at nuclear power plants  

Microsoft Academic Search

Water discharges from cooling towers constructed with asbestos fill were found to contain chrysotile--asbestos fibers at concentrations as high as 10⁸ fibers\\/liter. The major source of these fibers, appears to be the components of the towers rather than the air drawn through the towers or the makeup water taken into the towers. Suggested mechanisms for the release of chrysotile fibers

B. A. G

1979-01-01

447

Test and simulation of a solar-powered absorption cooling machine  

Microsoft Academic Search

At the Institut fuer Thermodynamik und Waermetechnik (ITW) a solar cooling machine has been built for demonstration purposes. The main part of the device is an absorber\\/desorber unit which is mounted inside a concentrating solar collector. The working pair consists of NH3 used as the refrigerant and SrCl2 used as the absorbing medium. Performance of the solar refrigeration unit was

Alfred Erhard; Erich Hahne

1997-01-01

448

Sidestream treatment of high silica cooling water and reverse osmosis desalination in geothermal power generation  

SciTech Connect

Bench scale and pilot plant test work has been performed on cooling water for silica reduction and water reuse, at DOE's Raft River Geothermal Site, Malta, Idaho in cooperation with EG and G (Idaho), Inc. Technical supervision was by Permutit. A novel process of rusting iron shavings was found effective and economical in reducing silica to less than 20 mg/l. Reverse Osmosis was investigated for water reuse after pretreatment and ion exchange softening.

Mindler, A.B.; Bateman, S.T.

1981-01-19

449

Power Handling and Responsivity of Submicron Wide Superconducting Coplanar Waveguide Resonators  

E-print Network

The sensitivity of microwave kinetic inductance detectors (MKIDs) based on coplanar waveguides (CPWs) needs to be improved by at least an order of magnitude to satisfy the requirements for space-based terahertz astronomy. Our aim is to investigate if this can be achieved by reducing the width of the CPW to much below what has typically been made using optical lithography (> 1 {\\mu}m). CPW resonators with a central line width as narrow as 300 nm were made in NbTiN using electron beam lithography and reactive ion etching. In a systematic study of quarter-wave CPW resonators with varying widths it is shown that the behavior of responsivity, noise and power handling as a function of width continues down to 300 nm. This encourages the development of narrow KIDs using Al in order to improve their sensitivity.

Janssen, R M J; Baselmans, J J A; de Visser, P J; Barends, R; Klapwijk, T M; 10.1007/s10909-012-0458-1

2012-01-01

450

Serial and parallel power equipment with high-temperature superconducting elements  

NASA Technical Reports Server (NTRS)

One of the prospective, practical applications of high-temperature superconductors is the fault-current limitation in electrical energy networks. The development and testing of experimental HTSC serial current limiters have been reported in the literature. A Hungarian electric power company has proposed the development of a parallel equipment for arc suppressing both in the industrial and customers' networks. On the basis of the company's proposal the authors have outlined the scheme of a compound circuit that can be applied both for current limitation and arc suppressing. In this paper the design principles and methods of the shunt equipment are presented. These principles involve the electrical, mechanical and cryogenic aspects with the special view on the electrical and mechanical connection between the HTSC material and the current lead. Preliminary experiments and tests have been carried out to demonstrate the validity of the design principles developed. The results of the experiments and of the technological investigations are presented.

Bencze, Laszlo; Goebl, Nandor; Palotas, Bela; Vajda, Istvan

1995-01-01

451

Performance simulation of the JPL solar-powered distiller. Part 1: Quasi-steady-state conditions. [for cooling microwave equipment  

NASA Technical Reports Server (NTRS)

A 37.85 cu m (10,000 gallons) per year (nominal) passive solar powered water distillation system was installed and is operational in the Venus Deep Space Station. The system replaced an old, electrically powered water distiller. The distilled water produced with its high electrical resistivity is used to cool the sensitive microwave equipment. A detailed thermal model was developed to simulate the performance of the distiller and study its sensitivity under varying environment and load conditions. The quasi-steady state portion of the model is presented together with the formulas for heat and mass transfer coefficients used. Initial results indicated that a daily water evaporation efficiency of 30% can be achieved. A comparison made between a full day performance simulation and the actual field measurements gave good agreement between theory and experiment, which verified the model.

Yung, C. S.; Lansing, F. L.

1983-01-01

452

Power-law decay of the velocity autocorrelation function of a granular fluid in the homogeneous cooling state  

NASA Astrophysics Data System (ADS)

The hydrodynamic part of the velocity autocorrelation function of a granular fluid in the homogeneous cooling state has been calculated by using mode-coupling theory for a finite system with periodic boundary conditions. The existence of the shearing instability, leading to a divergent behavior of the velocity flow fluctuations, is taken into account. A time region in which the velocity autocorrelation function exhibits a power-law decay, when time is measured by the number of collisions per particle, has been been identified. Also the explicit form of the exponential asymptotic long time decay has been obtained. The theoretical prediction for the power-law decay is compared with molecular dynamics simulation results, and a good agreement is found, after taking into account finite size corrections. The effects of a