Sample records for cooled superconducting power

  1. A novel cooling scheme for superconducting power cables

    NASA Astrophysics Data System (ADS)

    Ashworth, S. P.; Reagor, D. W.

    Long distance transmission of electrical power with superconducting cables is likely necessary for energy conservation and effective utilization of renewable energy sources. The performance and cost of such superconducting lines is as significantly influenced by cryogenic issues as by superconductor performance. One significant cryogenic issue is that in the usual method of cooling using sub-cooled cryogen flow there is a limited cable length before the cryogen needs to be re-cooled. This adds complexity and cost to the cable system. Here we address this problem by utilizing the latent heat of the cryogen without the complication of multi-phase flow. The cryogen is distributed to the superconducting components by spraying it through small holes in a pressurized line. The pressurized liquid exiting the holes turns into mixed liquid and vapor with a temperature near the boiling point of the cryogen at the pressure of the space surrounding the superconducting components. The pressure in the space surrounding the superconducting components is then kept near atmospheric by maintaining short distances to a vent. The sprayed liquid accumulates but rapidly vaporizes in response to the heat load, providing even cooling power at a fixed temperature for the entire length of the line. Our work indicates that it may be possible to implement a cooling system with much simplified cryogenic stations at the cable ends and allowing cable lengths of up to 100 km with no intermediate cooling stations.

  2. Cooling of the 200 m superconducting DC power transmission system at Chubu University

    NASA Astrophysics Data System (ADS)

    Watanabe, Hirofumi; Sun, Jian; Ivanov, Yury; Hamabe, Makoto; Kawahara, Toshio; Yamaguchi, Satarou

    The fourth cooling test of the superconducting DC power transmission system of Chubu University was conducted in August of 2011. The heat leak from the cryogenic pipe and the eect of reducing the outer pipe temperature were tested. The heat leak from the cryogenic pipe was improved relative to that recorded during the second cooling test performedintheprevious summer,a season similartothatin whichthe fourth cooling testwas conducted.Asigni?cant reduction of the outer pipe temperature was achieved by an infrared re?ective coating, and a reduction of the heat leak was observed.

  3. Peltier cooling of superconducting current leads

    Microsoft Academic Search

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

    2001-01-01

    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

  4. Peltier cooling of superconducting electronics

    Microsoft Academic Search

    J. W. Straehle; S. Rath; K.-J. Klingesberger; T. Nissel; S. G. Doettinger; C. A. Doettinger; R. P. Huebener; S. Kemmler-Sack

    1997-01-01

    The increase of the superconducting transition temperature in some of the cuprate superconductors to values higher than 130 K is generating strong interest in the exploration of Peltier cooling for the operation of superconducting electronics. In this case, we need materials with a sufficiently large figure of merit z down to temperatures near 100 K. We have performed measurements of

  5. Cooling and electrical excitation of 100 m superconducting power transmission cables

    SciTech Connect

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

    1980-01-01

    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.

  6. Power superconducting power transmission cable

    DOEpatents

    Ashworth, Stephen P. (Cambridge, GB)

    2003-01-01

    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.

  7. Prospects for Peltier cooling of superconducting electronics

    Microsoft Academic Search

    R. P Huebener; C. C Tsuei

    1998-01-01

    We report on a Peltier cooling experiment using commercially available Peltier modules and reaching 149K on the cold end. On the warm end the temperature was fixed at 282K by cooling water. For reaching the superconducting transition temperature of the cuprates, better thermoelectric materials must be developed. We discuss estimates of the figure of merit needed for achieving the operating

  8. Superconducting shield for solenoid of electron cooling system

    NASA Astrophysics Data System (ADS)

    Agapov, N. N.; Donets, D. E.; Drobin, V. M.; Kulikov, E. A.; Malinovski, H.; Pivin, R. V.; Smirnov, A. V.; Prokofichev, Yu. V.; Trubnikov, G. V.; Dorofeev, G. L.

    2012-07-01

    Ensuring the high homogeneity of a magnetic field in the straight solenoid of an electron cooling system is a very important task. In the electron cooling system of the collider in the NICA project, it is planned to use superconducting solenoids for the generation of a longitudinal magnetic field. Using of the superconducting shield is proposed to achieve the required homogeneity of the magnetic field in the cooling section. This article discusses the design of the superconducting shield and presents experimental and numerical studies into the homogeneity of the magnetic field in solenoids with the superconducting shield.

  9. Cooling of superconducting devices by liquid storage and refrigeration unit

    DOEpatents

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

    2013-08-20

    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.

  10. Direct cooled power electronics substrate

    DOEpatents

    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

    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.

  11. Magnetic Flux Dynamics in Horizontally Cooled Superconducting Cavities

    E-print Network

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

    2015-01-01

    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...

  12. Neutron star cooling constraints for color superconductivity in hybrid stars

    SciTech Connect

    Popov, S. B. [Sternberg Astronomical Institute, Universitetski pr. 13, RU-119992 Moscow (Russian Federation); Grigorian, H. [Institut fuer Physik, Universitaet Rostock, D-18051 Rostock (Germany); Department of Physics, Yerevan State University, 375049 Yerevan (Armenia); Blaschke, D. [Gesellschaft fuer Schwerionenforschung mbH (GSI), D-64291 Darmstadt (Germany); Bogoliubov Laboratory for Theoretical Physics, JINR Dubna, RU-141980 Dubna (Russian Federation)

    2006-08-15

    We apply the recently developed logN-logS test of compact star cooling theories for the first time to hybrid stars with a color superconducting quark matter core. Although there is not yet a microscopically founded superconducting quark matter phase that would fulfill constraints from cooling phenomenology, we explore the hypothetical 2SC+X phase and show that the magnitude and density dependence of the X-gap can be chosen to satisfy a set of tests: temperature-age (T-t), the brightness constraint, logN-logS, and the mass spectrum constraint. The latter test appears as a new conjecture from the present investigation.

  13. Progress on Superconducting Magnets for the MICE Cooling Channel

    SciTech Connect

    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

    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.

  14. Magnetar superconductivity versus magnetism: Neutrino cooling processes

    NASA Astrophysics Data System (ADS)

    Sinha, Monika; Sedrakian, Armen

    2015-03-01

    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.

  15. Solar-powered cooling system

    DOEpatents

    Farmer, Joseph C

    2013-12-24

    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.

  16. Heat pipe cooled power magnetics

    NASA Technical Reports Server (NTRS)

    Chester, M. S.

    1979-01-01

    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.

  17. Cryogenic performance of a cryocooler-cooled superconducting undulator

    SciTech Connect

    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

    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.

  18. FLOW COOLING OF SUPERCONDUCTING MAGNETS FOR SPACECRAFT APPLICATIONS

    Microsoft Academic Search

    A. J. Dietz; W. E. Audette; M. D. Barton; J. K. Hilderbrand; W. S. Marshall; C. M. Rey; D. S. Winter; A. J. Petro

    2008-01-01

    The development and testing of a flow cooling system for high-temperature superconducting (HTS) magnets is described. The system includes a turbo-Brayton cryocooler, a magnet thermal interface, and a magnet thermal isolation and support system. The target application is the Variable Specific Impulse Magnetoplasma Rocket (VASIMR). Turbo-Brayton coolers are well suited to such spacecraft applications, as they are compact, modular, lightweight,

  19. Flow Cooling of Superconducting Magnets for Spacecraft Applications

    Microsoft Academic Search

    A. J. Dietz; W. E. Audette; M. D. Barton; J. K. Hilderbrand; W. S. Marshall; C. M. Rey; D. S. Winter; A. J. Petro

    2008-01-01

    The development and testing of a flow cooling system for high-temperature superconducting (HTS) magnets is described. The system includes a turbo-Brayton cryocooler, a magnet thermal interface, and a magnet thermal isolation and support system. The target application is the Variable Specific Impulse Magnetoplasma Rocket (VASIMR). Turbo-Brayton coolers are well suited to such spacecraft applications, as they are compact, modular, lightweight,

  20. Thermoelectric cooling and power generation

    PubMed

    DiSalvo

    1999-07-30

    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

  1. Fundamental Power Couplers for Superconducting Cavities

    Microsoft Academic Search

    Isidoro E. Campisi

    2001-01-01

    Fundamental power couplers (FPC's) for superconducting cavities must meet very strict requirements to perform at high power levels (hundreds of kilowatts) and in a variety of conditions (CS, pulsed, travelling wave, standing wave) without adversely affecting the performance of the cavities they are powering. Producing good coupler designs and achieving operational performances in accelerator environments are challenging tasks that have

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

    NASA Astrophysics Data System (ADS)

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

    2013-10-01

    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.

  3. Thermoelectric Devices Cool, Power Electronics

    NASA Technical Reports Server (NTRS)

    2009-01-01

    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.

  4. Surface Power Radiative Cooling Tests

    NASA Astrophysics Data System (ADS)

    Vaughn, Jason; Schneider, Todd

    2006-01-01

    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.

  5. Superconductivity in the splat-cooled UMo alloys

    NASA Astrophysics Data System (ADS)

    Kim-Ngan, N.-T. H.; Sowa, S.; Krupska, M.; Paukov, M.; Tkach, I.; Havela, L.

    2015-03-01

    We have investigated the superconductivity in splat-cooled UMo alloys by low-temperature resistivity and specific-heat measurements down to 0.4 K. The ?-U materials, such as U-Mo15 (with 15 at.% Mo doping), exhibit a conventional BCS superconductivity with Tc = 2.1 K and upper critical field exceeding 5 T, much higher than that for ?-U materials. The alloys with <10 at.% Mo doping consist of a mixed ? + ?-U phase. The superconducting transition in the U-Mo6 revealed by a smooth decrease below 1.5 K and a sharp drop at 0.6 K in the resistivity indicating that ?-U grains are embedded in the ?-U matrix. The superconductivity transition was revealed by ?-type peak at Tc in the C(T) curve only for U-Mo15, while only one broad peak at Tc in the C(T) curves were observed for other UMo splats. With applying the magnetic fields, the resistivity jumps and specific-heat peaks move to lower temperatures. Invited talk at the 7th International Workshop on Advanced Materials Science and Nanotechnology IWAMSN2014, 2-6 November, 2014, Ha Long, Vietnam.

  6. Cooling of neutron stars with color superconducting quark cores

    SciTech Connect

    Grigorian, Hovik [Institut fuer Physik, Universitaet Rostock, D-18051 Rostock (Germany); Department of Physics, Yerevan State University, Alex Manoogian Street 1, 375025 Yerevan (Armenia); Blaschke, David [Fakultaet fuer Physik, Universitaet Bielefeld, D-33615 Bielefeld (Germany); Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Voskresensky, Dmitri [Theory Division, GSI mbH, D-64291 Darmstadt (Germany); Moscow Institute for Physics and Engineering, 115409 Moscow (Russian Federation)

    2005-04-01

    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{sub {center_dot}}. We study the cooling of these objects in isolation for different values of the gravitational mass. Our equation of state (EoS) allows for two-flavor color superconductivity (2SC) quark matter with a large quark gap ({approx}100 MeV) for u and d quarks of two colors that coexists with normal quark matter within a mixed phase in the hybrid star interior. We argue that, if the phases with unpaired quarks were allowed, the corresponding hybrid stars would cool too fast. If they occurred for M<1.3 M{sub {center_dot}}, as follows from our EoS, one could not appropriately describe the neutron star cooling data existing today. We discuss a ''2SC+X'' phase as a possibility for having all quarks paired in two-flavor quark matter under neutron star constraints, where the X gap is of the order of 10 keV-1 MeV. Density-independent gaps do not allow us to fit the cooling data. Only the presence of an X gap that decreases with increasing density would allow us to appropriately fit the data in a similar compact star mass interval to that following from a purely hadronic model. This scenario is suggested as an alternative explanation of the cooling data in the framework of a hybrid star model.

  7. A robust platform cooled by superconducting electronic refrigerators

    NASA Astrophysics Data System (ADS)

    Nguyen, H. Q.; Meschke, M.; Pekola, J. P.

    2015-01-01

    A biased tunnel junction between a superconductor and a normal metal can cool the latter electrode. Based on a recently developed cooler with high power and superior performance, we have integrated it with a dielectric silicon nitride membrane, and cooled phonons from 305 mK down to 200 mK. Without perforation and covered under a thin alumina layer, the membrane is rigorously transformed into a cooling platform that is robust and versatile for multiple practical purposes. We discussed our results and possibilities to further improve the device.

  8. Simulation of the quenching of an internally cooled superconducting magnet

    SciTech Connect

    Lue, J.W.; Miller, J.R.; Dresner, L.; Shen, S.S.

    1982-01-01

    Stability measurements on cable-in-conduit internally cooled superconductors have shown that the heat transferred to helium earlier will cause a pressure rise and induce a transient flow inside the conduit. In turn, this will enhance the heat transfer and help the superconductor to recover to its superconducting state. However, if the heat input is very high or if the heated length is very long, the pressure rise can be tremendous and the helium expulsion can be excessive. This paper describes the experimental results of simulating the quench of an entire hydraulic path. The measured thermal expulsion of helium and peak pressure during the quench are compared favorably with a similarity theory and a simple scaling relation.

  9. Superconducting helical solenoid systems for muon cooling experiment at Fermilab

    SciTech Connect

    Kashikhin, Vladimir S.; Andreev, Nikolai; /Fermilab; Johnson, Rolland P.; /MUONS Inc., Batavia; Kashikhin, Vadim V.; Lamm, Michael J.; Romanov, Gennady; Yonehara, Katsuya; Zlobin, Alexander V.; /Fermilab

    2007-08-01

    Novel configurations of superconducting magnet system for Muon Beam Cooling Experiment is under design at Fermilab. The magnet system has to generate longitudinal and transverse dipole and quadrupole helical magnetic fields providing a muon beam motion along helical orbit. It was found that such complicated field configuration can be formed by a set of circular coils shifted in transverse directions in such a way that their centers lay on the center of the helical beam orbit. Closed beam orbit configurations were also proposed and investigated. This paper describes the magnetic and mechanical designs and parameters of such magnetic system based on a NbTi Rutherford type cable. The helical solenoid fabrication, assembly and quench protection issues are presented.

  10. Bent Superconducting Solenoids for the Muon Cooling Experiment

    SciTech Connect

    Green, M.A.; Eyssa, Y.; Kenney, S.; Miller, J. R.; Prestemon, S.; Wang, S.T.

    1999-03-18

    This report describes some solenoid design work done for the cooling experiment for the muon collider collaboration. This report describes an analysis section of superconducting solenoids that have a center line induction of 3.0 T. The section is bent in the shape of an S. Each bend in the S bends the muon beam one radian (57.3 degrees). The warm bore diameter of the solenoid bent solenoid is 300 to 320 mm. The radius of the bend at the solenoid center line is 1000 mm. This report shows the results of three dimensional field calculations and presents a solenoid design that will include four TPC detectors that are 240 mm in diameter and 550 mm long as well as a 1300 mm long section of 1300 MHz RF cavities. The TPC sections need a solenoid wann bore diameter of about 300 320 mm while RF cavities require a warm bore diameter of 440 mm. The superconducting solenoid design must take into account the varying warm bore diameter requirements for the magnet string yet meet the stringent solenoidal field uniformity requirements within the active volume of the four TPCs.

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

    NASA Astrophysics Data System (ADS)

    Lagier, B.; Rousset, B.; Hoa, C.; Bonnay, P.

    2014-01-01

    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.

  12. New power-conditioning systems for superconducting magnetic energy storage

    Microsoft Academic Search

    Byung Moon Han

    1992-01-01

    This dissertation presents the development of new power-conditioning systems for superconducting magnetic energy storage (SMES), which can regulate fast and independently the active and reactive powers demanded in the ac network. Three new power-conditioning systems were developed through a systematic approach to match the requirements of the superconducting coil and the ac power network. Each of these new systems is

  13. Solid-Cryogen Cooling Technique for Superconducting Magnets of NMR and MRI

    E-print Network

    Iwasa, Yukikazu

    This paper describes a solid-cryogen cooling technique currently being developed at the M.I.T. Francis Bitter Magnet Laboratory for application to superconducting magnets of NMR and MRI. The technique is particularly ...

  14. Maglev cooling options for Nb{sub 3}Sn cables in conduit superconducting magnets

    SciTech Connect

    Longsworth, R.C. [APD Cryogenics Inc., Allentown, PA (United States)

    1994-12-31

    This paper reports on studies of cooling Nb{sub 3}Sn superconducting magnets in magnetically-levitated trains. Each car is designed to have six bogies with two cryostats per bogie and multiple coils in each cryostat which have gas-cooled cables in conduit windings that can have exit temperatures as high as 8 K. Refrigeration systems that are considered include the use of liquid helium (LHe) and liquid nitrogen (LN{sub 2}), supplied from central stations on a daily basis, on-board refrigerators that receive power from the guide way, and hybrid systems that use LN{sub 2} and LHe from central stations to reduce the power input and weight of an on-board refrigeration system. It is assumed that LN{sub 2} which is supplied from a central station, can be vented but that He would be recovered. The system for recovering and storing He on board the train for 24 hours of operation adds appreciable weight to the system and requires a significant amount of power for the recovery compressor. An on-board refrigerator that uses LN{sub 2} for 77 K refrigeration is lighter and uses less power than a refrigeration system that uses no cryogens. The system that is lightest and requires very little power input is one that uses LHe in a sealed system for refrigeration between 4.2 K and 8 K and LN{sub 2} for 77 K refrigeration.

  15. Low noise NbN lattice-cooled superconducting hot-electron bolometric mixers at submillimeter wavelengths

    Microsoft Academic Search

    Jonathan Kawamura; Raymond Blundell; Cheuk-Yu Edward Tong; Gregory Gol'Tsman; Eugene Gershenzon; Boris Voronov; Sergey Cherednichenko

    1997-01-01

    Lattice-cooled superconducting hot-electron bolometric mixers are used in a submillimeter-wave waveguide heterodyne receiver. The mixer elements are niobium nitride film with 3.5 nm thickness and ?10 ?m2 area. The local oscillator power for optimal performance is estimated to be 0.5 ?W, and the instantaneous bandwidth is 2.2 GHz. At an intermediate frequency centered at 1.4 GHz with 200 MHz bandwidth,

  16. Heterodyne mixing in diffusion-cooled superconducting aluminum hot-electron bolometers

    Microsoft Academic Search

    I. Siddiqi; A. Verevkin; D. E. Prober; A. Skalare; W. R. McGrath; P. M. Echternach; H. G. Leduc

    2002-01-01

    We present microwave (30 GHz) measurements on aluminum superconducting hot-electron bolometer (HEB) mixers. Aluminum HEB mixers have a lower superconducting transition temperature than niobium and niobium nitride devices, and are predicted to have improved sensitivity and require less local oscillator power. The devices studied consist of a narrow superconducting aluminum microbridge with contacts comprised of thick aluminum, titanium, and gold.

  17. Small high cooling power space cooler

    SciTech Connect

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

    2014-01-29

    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.

  18. Cooling Strings of Superconducting Devices below 2 K:the Helium II Bayonet Heat Exchanger

    Microsoft Academic Search

    P Lebrun; L Serio; L Tavian; R Van Weelderen

    1997-01-01

    High-energy particle accelerators and colliders contain long strings of superconducting devices - acceleration RF cavities and magnets - operating at high field, which may require cooling in helium II below 2 K. In order to maintain adequate operating conditions, the applied or generated heat loads must be extracted and transported with minimum temperature difference. Conventional cooling schemes based on conductive

  19. On the efficiency at maximum cooling power

    NASA Astrophysics Data System (ADS)

    Apertet, Y.; Ouerdane, H.; Michot, A.; Goupil, C.; Lecoeur, Ph.

    2013-08-01

    The efficiency at maximum power (EMP) of heat engines operating as generators is one corner stone of finite-time thermodynamics, the Curzon-Ahlborn efficiency \\eta_CA being considered as a universal upper bound. Yet, no valid counterpart to \\eta_CA has been derived for the efficiency at maximum cooling power (EMCP) for heat engines operating as refrigerators. In this letter we analyse the reasons of the failure to obtain such a bound and we demonstrate that, despite the introduction of several optimisation criteria, the maximum cooling power condition should be considered as the genuine equivalent of maximum power condition in the finite-time thermodynamics frame. We then propose and discuss an analytic expression for the EMCP in the specific case of exoreversible refrigerators.

  20. Heat pipe cooling of power processing magnetics

    NASA Technical Reports Server (NTRS)

    Hansen, I. G.; Chester, M.

    1979-01-01

    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.

  1. Pressure rise during the quench of a superconducting magnet using internally cooled conductors

    SciTech Connect

    Miller, J.R.; Dresner, L.; Lue, J.W.; Shen, S.S.; Yeh, H.T.

    1980-01-01

    Superconducting magnets cooled by supercritical helium flowing through internal conductor passages are an alternative to magnets cooled in a boiling pool. This alternative involves a possible large pressure increase in the captured volume of helium during a quench. In the US Large Coil Program (LCP), three of six coils to be tested will use internally cooled conductors. This paper describes experiments performed to understand the quench behavior of the Westinghouse coil. Agreement between experiment and theory is good. Also discussed is the extension of this work to the EURATOM coil and the Swiss coil, as well as to any coils wound with internally cooled conductors.

  2. Hybrid Wet/Dry Cooling for Power Plants (Presentation)

    SciTech Connect

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

    2006-02-01

    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.

  3. Application of Superconducting Power Cables to DC Electric Railway Systems

    NASA Astrophysics Data System (ADS)

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

    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.

  4. Steam-Electric Power-Plant-Cooling Handbook

    SciTech Connect

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

    1982-02-01

    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.

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

    SciTech Connect

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

    2014-01-29

    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.

  6. Cooling and Excitation Tests of a Thin 1 mphi× 1 m Superconducting Solenoid Magnet

    Microsoft Academic Search

    Hiromi Hirabayashi; Kimio Morimoto; Masayoshi Wake; Ryuji Yamada; Akira Yamamoto; Shigeki Mori; Ryozo Yoshizaki; Hisao Kawakami; Kunitaka Kondo; Katsuzo Aihara; Yoshiaki Kazawa; Hiroshi Kimura; Hisao Ogata; Ryusei Saito; Shohei Suzuki; Yasuhiko Miyake

    1982-01-01

    Cooling and excitation tests of a thin 1 mphi× 1 m superconducting solenoid magnet were performed. Quench properties were measured after inducing quenches with a heater. The magnet has a single layer aluminum-stabilized NbTi\\/Cu superconductor of 269 turns and the forced flow cooling method of two-phase helium was used. The design excitation current of the magnet is 4.5 kA to

  7. Polk power station syngas cooling system

    SciTech Connect

    Jenkins, S.D.

    1995-01-01

    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.

  8. The Application of High Temperature Superconducting Materials to Power Switches

    E-print Network

    March, S A; Ballarino, A

    2009-01-01

    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...

  9. a Rotating Heat Pipe for Cooling of Superconducting Machines

    NASA Astrophysics Data System (ADS)

    Jankowski, T. A.; Prenger, F. C.; Schmierer, E. N.; Razani, A.

    2008-03-01

    A curved rotating heat pipe for use in superconducting motor and generator applications is introduced here. The heat pipe shown here is built so that both the condenser and evaporator sections are parallel to the axis of rotation. The condenser section is concentric with the axis of rotation while the evaporator section can be placed in contact with off-axis heat sources in the rotating machine. The geometry is achieved by incorporating an S-shaped curve between the on-axis rotating condenser section and the off-axis revolving evaporator section. We show that because the heat pipe is a sealed, passive heat transfer device with nearly isothermal operation, the heat pipe concept may be advantageous when considering the overall refrigeration system used with the superconducting machine. High-speed, room temperature test data with this heat pipe geometry indicate that the working fluid in the heat pipe continued to circulate, resulting in heat transfer with a high effective thermal conductivity, with the heat pipe operating under the influence of centrifugal accelerations approaching 400 g.

  10. Emerging Two-Phase Cooling Technologies for Power Electronic Inverters

    Microsoft Academic Search

    2005-01-01

    In order to meet the Department of Energy's (DOE's) FreedomCAR and Vehicle Technologies (FVCT) goals for volume, weight, efficiency, reliability, and cost, the cooling of the power electronic devices, traction motors, and generators is critical. Currently the power electronic devices, traction motors, and generators in a hybrid electric vehicle (HEV) are primarily cooled by water-ethylene glycol (WEG) mixture. The cooling

  11. Power converter having improved fluid cooling

    SciTech Connect

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

    2007-03-06

    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.

  12. Superconducting power delivery systems for transmission and distribution applications

    SciTech Connect

    Kral, S.F.; Aslam, M.; Ribeiro, P.F.; Huang, X.; Xu, M. [Babcock and Wilcox, Lynchburg, VA (United States)

    1995-10-01

    Transmission and distribution power systems are presently experiencing tremendous changes in both load requirements and system operation. End-users demand increased reliability and power quality. System operations change to optimize the distribution and number of generation sources to take advantage of load diversity and fuel availability. Superconducting Magnetic Energy Storage (SMES) and modern power electronics systems emerge as technologies enabling power utility systems to adapt to these changes. These systems deliver services unique and previously unavailable and the authors suggest the term Superconducting Power Systems to describe them. Babcock and Wilcox (B and W) is working with Anchorage Municipal Light and Power (ML and P) to design, manufacture and install a 50 MW, 1,800 MJ system in Anchorage, Alaska. The system will be commissioned in early 1998.

  13. Cooling Concepts for High Power Density Magnetic Devices

    Microsoft Academic Search

    J. Biela; J. W. Kolar

    2007-01-01

    In the area of power electronics there is a general trend to higher power densities. In order to increase the power density the systems must be designed optimally concerning topology, semiconductor selection, etc. and the volume of the components must be decreased. The decreasing volume comes along with a reduced surface for cooling. Consequently, new cooling methods are required. In

  14. Performance Analysis of XCPC Powered Solar Cooling Demonstration Project

    NASA Astrophysics Data System (ADS)

    Widyolar, Bennett K.

    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.

  15. Cooling Strings of Superconducting Devices below 2 K the Helium II Bayonet Heat Exchanger

    E-print Network

    Lebrun, P; Tavian, L; Van Weelderen, R

    1998-01-01

    High-energy particle accelerators and colliders contain long strings of superconducting devices - acceleration RF cavities and magnets - operating at high field, which may require cooling in helium II below 2 K. In order to maintain adequate operating conditions, the applied or generated heat loads must be extracted and transported with minimum temperature difference. Conventional cooling schemes based on conductive or convective heat transport in pressurized helium II very soon reach their intrinsic limits of thermal impedance over extended lengths. We present the concept of helium II bayonet heat exchanger, which has been developed at CERN for the magnet cooling scheme of the Large Hadron Collider (LHC), and describe its specific advantages as a slim, quasi-isothermal heat sink. Experimental results obtained on several test set-ups, and a prototype magnet string have permitted to validate its performance and sizing rules, for transporting linear heat loads in the W.m-1 range over distances of several tens o...

  16. Power module integrated cooling design using CFD simulation

    Microsoft Academic Search

    O. Karim; C. Schaeffer; B. Mallet; M. Coyaud; E. Gimet

    2001-01-01

    Thermal grease used in classical power module water-cooling takes 40 percent of the water-cooled heat sink thermal resistance. This part which belong to conduction phenomena can be suppressed using a direct cooling method. In this paper, the basic conduction term provided by the component packaging is firstly determined, using several methods. Then mini water-cooled channels are directly machined in a

  17. Cool Chips: Opportunities and Implications for Power and Thermal Management

    Microsoft Academic Search

    Sheng-Chih Lin; Kaustav Banerjee

    2008-01-01

    Alongside innovative device, circuit, and microarchitecture level techniques to alleviate power and thermal problems in nanoscale CMOS-based integrated circuits (ICs), chip cooling could be an effective knob for power and thermal management. This paper analyzes IC cooling while focusing on the practical temperature range of operation. Comprehensive analyses of chip cooling for various nanometer scale bulk-CMOS and silicon-on-insulator (SOI) technologies

  18. High-temperature cooling power of the superfluid Stirling refrigerator

    SciTech Connect

    Brisson, J.G.; Swift, G.W. [Los Alamos National Lab., NM (United States)

    1995-02-01

    Above 1 Kelvin, the measured cooling power of the superfluid Stirling refrigerator is significantly greater than would be expected simply from a classical ideal gas of {sup 3}He quasiparticles. Analysis shows that this increased cooling power is due to the presence of the {sup 4}He excitations.

  19. Low noise NbN lattice-cooled superconducting hot-electron bolometric mixers at submillimeter wavelengths

    SciTech Connect

    Kawamura, J.; Blundell, R.; Tong, C.E. [Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138 (United States); Goltsman, G.; Gershenzon, E.; Voronov, B.; Cherednichenko, S. [Moscow State Pedagogical University, Moscow, 119435 (Russia)] [Moscow State Pedagogical University, Moscow, 119435 (Russia)

    1997-03-01

    Lattice-cooled superconducting hot-electron bolometric mixers are used in a submillimeter-wave waveguide heterodyne receiver. The mixer elements are niobium nitride film with 3.5 nm thickness and {approximately}10 {mu}m{sup 2} area. The local oscillator power for optimal performance is estimated to be 0.5 {mu}W, and the instantaneous bandwidth is 2.2 GHz. At an intermediate frequency centered at 1.4 GHz with 200 MHz bandwidth, the double sideband receiver noise temperature is 410 K at 430 GHz. The receiver has been used to detect molecular line emission in a laboratory gas cell. {copyright} {ital 1997 American Institute of Physics.}

  20. New power-conditioning systems for superconducting magnetic energy storage

    NASA Astrophysics Data System (ADS)

    Han, Byung Moon

    1992-06-01

    This dissertation presents the development of new power-conditioning systems for superconducting magnetic energy storage (SMES), which can regulate fast and independently the active and reactive powers demanded in the ac network. Three new power-conditioning systems were developed through a systematic approach to match the requirements of the superconducting coil and the ac power network. Each of these new systems is composed of ten 100-MW modules connected in parallel to handle the large current through the superconducting coil. The first system, which was published in the IEEE Transactions on Energy Conversion, consists of line-commutated 24-pulse converter, a thyristor-switched tap-changing transformer, and a thyristor-switched capacitor bank. The second system, which was accepted for publication in the IEEE Transactions on Energy Conversion, consists of a 12-pulse GTO (gate turn-off thyristor) converter and a thyristor-switched tap-changing transformer. The third system, which was submitted to the International Journal of Energy System, consists of a dc chopper and a voltage-source PWM (pulse width modulation) converter. The operational concept of each new system is verified through mathematical analyses and computer simulations. The dynamic interaction of each new system with the ac network and the superconducting coil is analyzed using a simulation model with EMTP (electro-magnetic transients program). The analysis results prove that each new system is feasible and realizable. Each system can regulate the active and reactive powers of the utility network rapidly and independently, and each offer a significant reduction of the system rating by reducing the reactive power demand in the converter. Feasible design for each new system was introduced using a modular design approach based on the 1000 MW/5000 MWH plant, incorporating commercially available components and proven technologies.

  1. New power-conditioning systems for superconducting magnetic energy storage

    SciTech Connect

    Han, B.M.

    1992-01-01

    This dissertation presents the development of new power-conditioning systems for superconducting magnetic energy storage (SMES), which can regulate fast and independently the active and reactive powers demanded in the ac network. Three new power-conditioning systems were developed through a systematic approach to match the requirements of the superconducting coil and the ac power network. Each of these new systems is composed of ten 100-MW modules connected in parallel to handle the large current through the superconducting coil. The first system, which was published in the IEEE Transactions on EnergyConversion, consists of line-commutated 24-pulse converter, a thyristor-switched tap-changing transformer, and a thyristor-switched capacitor bank. The second system, which was accepted for publication in the IEEE Transactions on Energy Conversion, consists of a 12-pulse GTO (gate turn-off thyristor) converter and a thyristor-switched tap-changing transformer. The third system, which was submitted to the International Journal of Energy System, consists of a dc chopper and a voltage-source PWM (pulse width modulation) converter. The operational concept of each new system is verified through mathematical analyses and computer simulations. The dynamic interaction of each new system with the ac network and the superconducting coil is analyzed using a simulation model with EMTP (electro-magnetic transients program). The analysis results prove that each new system is feasible and realizable. Each system can regulate the active and reactive powers of the utility network rapidly and independently, and each offer a significant reduction of the system rating by reducing the reactive power demand in the converter. Feasible design for each new system was introduced using a modular design approach based on the 1000 MW/5000 MWH plant, incorporating commercially available components and proven technologies.

  2. Power and capacity reduction scheme for tokamak poloidal field power supply using superconducting coils

    SciTech Connect

    Yokota, K.; Kondoh, J.; Shimada, R. [Tokyo Inst. of Tech., Tokyo (Japan). Research Lab. for Nuclear Reactors

    1995-12-31

    A new-type Poloidal Field (PF) Coil power supply for future Tokamak reactors, aimed at removing the disturbance to the utility power system and reducing the power supply capacity, is proposed. PF power supply requires reductions of the capacity and the enormous regenerative power, by introducing a superconducting coil to the power supply. The new scheme of the circuit is described. After analyzing the start-up scenario of ITER, the concept of the new system is demonstrated.

  3. Test of a high Tc superconducting power transformer

    Microsoft Academic Search

    Kyeong Dal Choi; Hee Joon Lee; Gueesoo Cha; Kyung Woo Ryu; Woo Seok Kim; Song Yop Hahn

    2000-01-01

    A single-phase power transformer with windings made of Tc superconducting tapes was fabricated and tested. The tapes are made of Bi-2223 imbedded in a silver alloy matrix. The primary and secondary windings are made of double pancake coil. The rated voltages of the windings are 220\\/110 V. Four pancake type coil windings are stacked on the core. The inner two

  4. 77 FR 73056 - Initial Test Programs for Water-Cooled Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-07

    ...Test Programs for Water-Cooled Nuclear Power Plants AGENCY: Nuclear Regulatory...Test Programs for Water-Cooled Nuclear Power Plants.'' This guide describes...ITPs) for light water cooled nuclear power plants. DATES: Submit...

  5. 78 FR 35330 - Initial Test Programs for Water-Cooled Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-12

    ...Test Programs for Water-Cooled Nuclear Power Plants AGENCY: Nuclear Regulatory...Test Programs for Water-Cooled Nuclear Power Plants.'' This guide describes...ITPs) for light water cooled nuclear power plants. ADDRESSES: Please...

  6. Results of the APT RF power coupler development for superconducting linacs.

    SciTech Connect

    Schmierer, E. N. (Eric N.); Haynes, W. B. (William B.); Krawczyk, F. L. (Frank L.); Gautier, D. C. (Donald Cort); Gioia, J. G. (Jack G.); Madrid, M. A. (Michael A.); Lujan, R. E. (Richard E.); Chan, K. D. (Kwok-Chi D.); Schrage, D. L. (Dale L.); Smith, B. G. (Brian G.); Waynert, J. A. (Joseph A.); Rusnak, B. (Brian)

    2001-01-01

    For the new baseline APT (Accelerator Production of Tritium) linac design, the power couplers are required to transmit 420 kW of CW RF power to the superconducting cavities at 700 MHz. These couplers consist of an airside waveguide-to-coax transition, an air/vacuum break made by two planar, coaxial windows, and a vacuum-side coaxial antenna section. The coaxial antenna allows adjustability of the RF matching to the superconducting cavities. Design, fabrication, and testing of the power coupler/window occurred over the last four years, and room temperature testing of the prototype design is complete. Coupler/window assemblies have transmitted power to 1 MW, CW and have handled full reflected 850 kW, CW over a limited standing-wave phase range. Couplers were tested with a portion of the outer conductor cooled by liquid nitrogen to study the effects of condensed gases. No hard multipacting barriers were encountered during any of this room temperature testing. Final results, conclusions, and lessons learned about the coupler design, fabrication, and testing will be discussed.

  7. Development of a solar-powered passive ejector cooling system

    Microsoft Academic Search

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

    2001-01-01

    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

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

    Microsoft Academic Search

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

    2009-01-01

    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

  9. Emerging Two-Phase Cooling Technologies for Power Electronic Inverters

    SciTech Connect

    Hsu, J.S.

    2005-08-17

    In order to meet the Department of Energy's (DOE's) FreedomCAR and Vehicle Technologies (FVCT) goals for volume, weight, efficiency, reliability, and cost, the cooling of the power electronic devices, traction motors, and generators is critical. Currently the power electronic devices, traction motors, and generators in a hybrid electric vehicle (HEV) are primarily cooled by water-ethylene glycol (WEG) mixture. The cooling fluid operates as a single-phase coolant as the liquid phase of the WEG does not change to its vapor phase during the cooling process. In these single-phase systems, two cooling loops of WEG produce a low temperature (around 70 C) cooling loop for the power electronics and motor/generator, and higher temperature loop (around 105 C) for the internal combustion engine. There is another coolant option currently available in automobiles. It is possible to use the transmission oil as a coolant. The oil temperature exists at approximately 85 C which can be utilized to cool the power electronic and electrical devices. Because heat flux is proportional to the temperature difference between the device's hot surface and the coolant, a device that can tolerate higher temperatures enables the device to be smaller while dissipating the same amount of heat. Presently, new silicon carbide (SiC) devices and high temperature direct current (dc)-link capacitors, such as Teflon capacitors, are available but at significantly higher costs. Higher junction temperature (175 C) silicon (Si) dies are gradually emerging in the market, which will eventually help to lower hardware costs for cooling. The development of high-temperature devices is not the only way to reduce device size. Two-phase cooling that utilizes the vaporization of the liquid to dissipate heat is expected to be a very effective cooling method. Among two-phase cooling methods, different technologies such as spray, jet impingement, pool boiling and submersion, etc. are being developed. The Oak Ridge National Laboratory (ORNL) is leading the research on a novel floating refrigerant loop that cools high-power electronic devices and the motor/generator with very low cooling energy. The loop can be operated independently or attached to the air conditioning system of the vehicle to share the condenser and other mutually needed components. The ability to achieve low cooling energy in the floating loop is attributable to the liquid refrigerant operating at its hot saturated temperature (around 50 C+). In an air conditioning system, the liquid refrigerant is sub-cooled for producing cool air to the passenger compartment. The ORNL floating loop avoids the sub-cooling of the liquid refrigerant and saves significant cooling energy. It can raise the coefficient of performance (COP) more than 10 fold from that of the existing air-conditioning system, where the COP is the ratio of the cooled power and the input power for dissipating the cooled power. In order to thoroughly investigate emerging two-phase cooling technologies, ORNL subcontracted three university/companies to look into three leading two-phase cooling technologies. ORNL's assessments on these technologies are summarized in Section I. Detailed descriptions of the reports by the three university/companies (subcontractors) are in Section II.

  10. Thermoacoustic Duplex Technology for Cooling and Powering a Venus Lander

    NASA Astrophysics Data System (ADS)

    Walker, A. R.; Haberbusch, M. S.; Sasson, J.

    2015-04-01

    A Thermoacoustic Stirling Heat Engine (TASHE) is directly coupled to a Pulse Tube Refrigerator (PTR) in a duplex configuration, providing simultaneous cooling and electrical power, thereby suiting the needs of a long-lived Venus lander.

  11. International development of superconducting magnets for fusion power

    SciTech Connect

    Haubenreich, P.N.; Shimamoto, S.; Komarek, P.; Vecsey, G.

    1989-03-01

    In the 10-year-long Large Coil Task, the U.S., EURATOM, Japan and Switzerland separately designed and jointly tested six superconducting toroidal field coils, having 2.5 x 3.5-m bores. Three coils were bath-cooled; three used forced flow. Five used NbTi conductors; one Nb/sub 3/Sn. All were fully instrumented. All coils surpassed 8-T design criteria, reaching peak fields of 9.0 T. Tests demonstrated tolerances for internal heating and safety under abnormal conditions (e.g., loss of flow). Data were gained in experiments to extreme conditions. This paper summarizes results, both technical and with regard to successful international collaboration.

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

    SciTech Connect

    Kutscher, C.; Costenaro, D.

    2002-08-01

    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 summer days, compared to winter performance. This problem of reduced summer performance is exacerbated by the fact that electricity has a higher value in the summer. This paper describes a spreadsheet model that was developed to assess the cost and performance of four methods for using supplemental evaporative cooling to boost summer performance: (1) pre-cooling with spray nozzles, (2) pre-cooling with Munters media, (3) a hybrid combination of nozzles and Munters media, and (4) direct deluge cooling of the air-cooled condenser tubes. Although all four options show significant benefit, deluge cooling has the potential to be the most economic. However, issues of scaling and corrosion would need to be addressed.

  13. Superconductivity

    SciTech Connect

    Langone, J.

    1989-01-01

    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.

  14. Dependence of the residual surface resistance of superconducting radio frequency cavities on the cooling dynamics around Tc

    NASA Astrophysics Data System (ADS)

    Romanenko, A.; Grassellino, A.; Melnychuk, O.; Sergatskov, D. A.

    2014-05-01

    We report a strong effect of the cooling dynamics through Tc 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.

  15. Water Cooling of High Power Light Emitting Diode Henrik Srensen

    E-print Network

    Berning, Torsten

    Water Cooling of High Power Light Emitting Diode Henrik Sørensen Department of Energy Technology and product lifetime. The high power Light Emitting Diodes (LED) belongs to the group of electronics 1411 Email: hs@et.aau.dk ABSTRACT The development in light technologies for entertainment is moving

  16. Novel concept for a space power distribution busbar using HTS materials and passive cooling

    NASA Astrophysics Data System (ADS)

    Shimko, Martin A.; Crowley, Christopher J.; Wallis, Peter N.

    1992-04-01

    This paper presents the performance, defines the range of applications, and shows the feasibility of using high temperature superconducting (HTS) materials with passive heat rejection for space power transmission. A conceptual design for the busbar is presented, and mass and resistive energy losses are estimated for various missions, power levels, and current types (AC and DC). All applications display a large increase in power transmission efficiency, while mass comparisons show the passively cooled HTS busbar mass ranges from 12% of the mass of a copper busbar at geosynchronous orbit (GEO) and beyond, to 38% at a 1000 km earth orbit (LEO). The design of the HTS conductor is novel, consisting of interleaved HTS strip conductors (HTS plus substrate) separated by dielectric insulating material. Appropriate HTS materials are presently available in long length (?100 m) with current densities (?1000 amp/cm2) and critical temperatures (95 K) which make the passively cooled busbar feasible. An original numerical model for the conductor/radiator assembly is described which includes the effects of solar insolation, reflected and IR thermal loads from the earth, and internally generated losses in the HTS. Completely passive operation at low earth orbits (LEO) of 1000 km is enabled by a novel asymmetric design for a directional radiator that includes a unique back-to-back busbar configuration that does not require active pointing. The design includes copper conductor downleads employing the same passive cooling scheme.

  17. High-power passive-cooled diode laser device

    NASA Astrophysics Data System (ADS)

    Bonati, Guido F.; Hennig, Petra; Rollig, Ullrich; Lorenzen, Dirk

    2003-06-01

    In order to achieve a thermally stable diode laser system based on high power diode laser bars, actively cooled heatsinks in form of micro channel heat sinks (MCHS) are used to face the power loss density of 106 W/m2 while requiring a minimum device volume. At identical junction temperature, passively cooled diode lasers are usually lower in power and the device volume is much higher due to the heat flux spreading design of passive heatsinks. However, as a matter of principle, the cooling with MCHS sinks requires a sealing between the heat sink itself and the system around. This sealing is usually achieved by o-rings, what can never avoid the transfer of vapor from the cooling system into the vicinity of the diode laser. Extreme requirements on availability, which lead to corresponding lifetime requirements, like in telecom applications, already require passively cooled diode lasers without any water in the inner system boundaries. For applications not requiring the extreme compact design volume of actively cooled diode lasers but requiring extreme lifetime or a minimum outlay on the periphery, we started looking into passively cooled diode laser stacks. To achieve a minimized temperature rise in the junction, we already developed a new copper-based heat sink, spreading the power loss in an optimized manner. Based on this heatsink, we started developing a heat exchanger with a low thermal resistance while keeping the water out of the inner system boundaries. The thermal resistance is low enough to run up to 12 passively cooled diode lasers on a low ambient temperature with a minimum of periphery requirements.

  18. Liquid metal cooled reactors for space power applications

    NASA Technical Reports Server (NTRS)

    Bailey, S.; Vaidyanathan, S.; Van Hoomissen, J.

    1985-01-01

    The technology basis for evaluation of liquid metal cooled space reactors is summarized. Requirements for space nuclear power which are relevant to selection of the reactor subsystem are then reviewed. The attributes of liquid metal cooled reactors are considered in relation to these requirements in the areas of liquid metal properties, neutron spectrum characteristics, and fuel form. Key features of typical reactor designs are illustrated. It is concluded that liquid metal cooled fast spectrum reactors provide a high confidence, flexible option for meeting requirements for SP-100 and beyond.

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

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

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

  20. Design of a cryogenic system for a 20m direct current superconducting MgB2 and YBCO power cable

    NASA Astrophysics Data System (ADS)

    Cheadle, Michael J.; Bromberg, Leslie; Jiang, Xiaohua; Glowacki, Bartek; Zeng, Rong; Minervini, Joseph; Brisson, John

    2014-01-01

    The Massachusetts Institute of Technology, the University of Cambridge in the United Kingdom, and Tsinghua University in Beijing, China, are collaborating to design, construct, and test a 20 m, direct current, superconducting MgB2 and YBCO power cable. The cable will be installed in the State Key Laboratory of Power Systems at Tsinghua University in Beijing beginning in 2013. In a previous paper [1], the cryogenic system was briefly discussed, focusing on the cryogenic issues for the superconducting cable. The current paper provides a detailed discussion of the design, construction, and assembly of the cryogenic system and its components. The two-stage system operates at nominally 80 K and 20 K with the primary cryogen being helium gas. The secondary cryogen, liquid nitrogen, is used to cool the warm stage of binary current leads. The helium gas provides cooling to both warm and cold stages of the rigid cryostat housing the MgB2 and YBCO conductors, as well as the terminations of the superconductors at the end of the current leads. A single cryofan drives the helium gas in both stages, which are thermally isolated with a high effectiveness recuperator. Refrigeration for the helium circuit is provided by a Sumitomo RDK415 cryocooler. This paper focuses on the design, construction, and assembly of the cryostat, the recuperator, and the current leads with associated superconducting cable terminations.

  1. Evacuation time of cryogenic pipes for superconducting power transmission

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

    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.

  2. Investigation into the use of solid nitrogen to create a ''Thermal Battery'' for cooling a portable high-temperature superconducting magnet

    NASA Astrophysics Data System (ADS)

    Hales, P.; Jones, H.; Milward, S.; Harrison, S.

    2005-02-01

    The design of a portable, "stand-alone" cooling system, for use with a high-temperature superconducting (HTS) magnet, is discussed. The HTS magnet is used to propel a magnetohydrodynamically powered model boat (approximately 120 cm × 60 cm). The aim of this investigation was to establish the suitability of solid nitrogen for use in the stand-alone cooling system, and determine the optimum method for exploiting its cooling power. It was found that obtaining good thermal contact between solid nitrogen and its container is very difficult if the nitrogen is frozen under vacuum, due to the formation of a thermal barrier between the nitrogen and its container. This problem is overcome if the nitrogen is frozen via conduction cooling from cold helium gas (at ˜4.2 K); and the design for a near isothermal "thermal battery" based on this principle is presented. This thermal battery has been constructed and integrated into the HTS magnet system onboard the model boat, and the results from the first trials of this system are presented here.

  3. Gas-cooled reactor power systems for space

    SciTech Connect

    Walter, C.E.

    1987-01-01

    In this paper the characteristics of six designs for power levels of 2, 10, and 20 MWe for operating times of 1 and 7 y are described. The operating conditions for these arbitrary designs were chosen to minimize system specific mass. The designs are based on recent work which benefits from earlier analyses of nuclear space power systems conducted at our Laboratory. Both gas- and liquid-cooled reactors had been considered. Pitts and Walter (1970) reported on the results of a detailed study of a 10-MWe lithium-cooled reactor in a potassium Rankine system. Unpublished results (1966) of a computer analysis provide details of an argon-cooled reactor in an argon Brayton system. The gas-cooled reactor design was based on extensive development work on the 500-MWth reactor for the nuclear ramjet (Pluto) as described by Walter (1964). The designs discussed here draw heavily on the Pluto project experience, which culminated in a successful full-power ground test as reported by Reynolds (1964). At higher power levels gas-cooled reactors coupled with Brayton systems with advanced radiator designs become attractive.

  4. Resistance and Cooling Power of Various Radiators

    NASA Technical Reports Server (NTRS)

    Smith, R H

    1928-01-01

    This reports combines the wind tunnel results of radiator tests made at the Navy Aerodynamical Laboratory in Washington during the summers of 1921, 1925, and 1926. In all, 13 radiators of various types and capacities were given complete tests for figure of merit. Twelve of these were tested for resistance to water flow and a fourteenth radiator was tested for air resistance alone, its heat dissipating capacity being known. All the tests were conducted in the 8 by 8 foot tunnel, or in its 4 by 8 foot restriction, by the writer and under conditions as nearly the same as possible. That is to say, as far as possible, the general arrangement and condition of the apparatus, the observation intervals, the ratio of water flow per unit of cooling surface, the differential temperatures, and the air speeds were the same for all.

  5. Zig–Zag-Array Superconducting Resonators for Relatively High-Power Applications

    Microsoft Academic Search

    George L. Matthaei; Balam A. Willemsen; Eric M. Prophet; Genichi Tsuzuki

    2008-01-01

    Since power handling of superconducting resonators is severely limited by current density saturation, it is proposed to form resonators having their incident power and resulting currents divided within interior arrays of \\

  6. Thermally matched fluid cooled power converter

    DOEpatents

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

    2005-06-21

    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.

  7. Concurrent Wind Cooling in Power Transmission Lines

    SciTech Connect

    Jake P Gentle

    2012-08-01

    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.

  8. Modular power converter having fluid cooled support

    DOEpatents

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

    2005-09-06

    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.

  9. Modular power converter having fluid cooled support

    SciTech Connect

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

    2005-12-06

    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.

  10. Combined cooling heat and power in supermarkets

    Microsoft Academic Search

    G. G Maidment; R. M Tozer

    2002-01-01

    With recent initiatives from the UK government on reduced energy use, energy efficient systems such as combined heat and power (CHP) have been considered for new applications, including supermarkets. In these commercial buildings, the seasonal demand for heat results in underutilisation of the CHP equipment, limiting the primary energy savings that may be achieved. To increase the utilisation time, it

  11. Gas-cooled reactor power systems for space

    SciTech Connect

    Walter, C.E.

    1987-01-01

    Efficiency and mass characteristics for four gas-cooled reactor power system configurations in the 2- to 20-MWe power range are modeled. The configurations use direct and indirect Brayton cycles with and without regeneration in the power conversion loop. The prismatic ceramic core of the reactor consists of several thousand pencil-shaped tubes made from a homogeneous mixture of moderator and fuel. The heat rejection system is found to be the major contributor to system mass, particularly at high power levels. A direct, regenerated Brayton cycle with helium working fluid permits high efficiency and low specific mass for a 10-MWe system.

  12. Development Project of Supercritical-water Cooled Power Reactor

    Microsoft Academic Search

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

    2002-01-01

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

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

    Microsoft Academic Search

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

    2012-01-01

    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

  14. The Design and Winding Method of a Conduction-Cooled 1.5 T Bi2223 High Temperature Superconducting Magnet

    Microsoft Academic Search

    Jiayin Ling; Chen Gu; Timing Qu; Zhenghe Han

    2010-01-01

    A conduction-cooled 1.5 T high temperature superconducting (HTS) magnet was designed. The magnet will be used to provide a steady and confining magnetic field, which requires the uniformity within ??5% of the central field, over a ?? 25 mm ?? 120 mm cylindrical region. Totally 0.8 km Bi-2223 HTS tapes will be used to wind 22 double-pancakes. The inner and

  15. SUPERCONDUCTING PHOTOINJECTOR

    SciTech Connect

    BEN-ZVI,I.; BURRILL, A.; CALAGA, R.; CHANG, X.; GROVER, R.; GUPTA, R.; HAHN, H.; HAMMONS, L.; KAYRAN, D.; KEWISCH, J.; LAMBIASE, R.; LITVINENKO, V.; MCINTYRE, G.; NAIK, D.; PATE, D.; PHILLIPS, D.; POZDEYEV, E.; RAO, T.; SMEDLEY, J.; THAN, R.; TODD, R.; WEISS, D.; WU, Q.; ZALTSMAN, A.; ET AL.

    2007-08-26

    One of the frontiers in FEL science is that of high power. In order to reach power in the megawatt range, one requires a current of the order of one ampere with a reasonably good emittance. The superconducting laser-photocathode RF gun with a high quantum efficiency photocathode is the most natural candidate to provide this performance. The development of a 1/2 cell superconducting photoinjector designed to operate at up to a current of 0.5 amperes and beam energy of 2 MeV and its photocathode system are the subjects covered in this paper. The main issues are the photocathode and its insertion mechanism, the power coupling and High Order Mode damping. This technology is being developed at BNL for DOE nuclear physics applications such as electron cooling at high energy and electron ion colliders..

  16. Personal cooling in nuclear power stations. Final report

    SciTech Connect

    Kamon, E.

    1983-03-01

    Two approaches to personal, non-restrictive cooling of workers exposed to high-temperature work environments in nuclear power plants were evaluated. Both approaches involved a cooling garment designed to be worn under the protective clothing donned in penetration into radiation areas. One garmet was developed to cool by direct body contact with small packets of frozen water enclosed in the pockets of a shirt. The other garmets cooled by circulating a cooled liquid through capillaries in a vest and head cap (System A) or a vest (System B). Testing was conducted in a laboratory simulation of high ambient temperature (55/sup 0/C) and moderate metabolic heat production (200 to 300 kcal/h). Exposure time without cooling (control) was 52 minutes (Group 1) for the workloads demanding 200 kcal/h (48 minutes for Group 2). A long garmet with 7.2 kg of frozen water (LFWG) increased mean exposure time over the control by 242% (163% for the same garmet with 6.2 kg of frozen water). A short-version garmet with 3.8 kg of frozen water (SFWG) increased the stay time by 115%. The circulating-liquid garmets increased mean exposure time 35% (System A) and 27% (System B) over the control. In field observation, the LFWG with 6.2 kg of frozen water improved stay time by 125%.

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

    Microsoft Academic Search

    W. S. Koncinski; A. W. Murphy; R. A. Hawsey

    1994-01-01

    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

  18. Potential minimum cost of electricity of superconducting coil tokamak power reactors

    Microsoft Academic Search

    R. L. Reid; Y.-K. M. Peng

    1989-01-01

    The potential minimum cost of electricity (COE) for superconducting tokamak power reactors is estimated by increasing the physics (confinement, beta-limit, bootstrap current fraction) and technology (neutral beam energy, toroidal field, or TF, coil allowable stresses, divertor heat flux, superconducting coil critical field, critical temperature, and quench temperature rise) constraints far beyond those assumed for the ITER (International Thermonuclear Experimental Reactor)

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

    SciTech Connect

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

    2007-01-01

    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

  20. Superconductivity

    SciTech Connect

    Mayo, J.L.

    1988-01-01

    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.

  1. Active cooling solutions for high power laser diodes stacks

    NASA Astrophysics Data System (ADS)

    Karni, Yoram; Klumel, Genady; Levy, Moshe; Berk, Yuri; Openhaim, Yaki; Gridish, Yaakov; Elgali, Asher; Avisar, Meir; Blonder, Moshe; Sagy, Hila; Gertsenshtein, Alex

    2008-02-01

    High power water cooled diode lasers find increasing demand in biomedical, cosmetic and industrial applications, where very high brightness and power are required. The high brightness is achieved either by increasing the power of each bar or by reducing the emitting area of the stacks. Two new products will be presented: Horizontal CW stacks with output power as high as 1kW using 80 W bars with emitting area width as low as 50 ?m Vertical QCW stacks with output power as high as 1.2kW using 120 W bars. Heat removal from high power laser stacks often requires microchannel coolers operated with finely filtered deionized (DI) water. However, for certain industrial applications the reliability of this cooling method is widely considered insufficient due to leakage failures caused the highly corrosive DI water. Two solutions to the above problem will be discussed. A microchannel cooler-based package, which vastly reduces the corrosion problem, and a novel high-power laser diode stack that completely eliminates it. The latter solution is especially effective for pulsed applications in high duty cycle range.

  2. Power system stabilization by superconducting magnetic energy storage with solid-state phase shifter

    Microsoft Academic Search

    Y. Mitani; T. Uranaka; K. Tsuji

    1995-01-01

    In this paper, a new configuration of power system controller with a combination of superconducting magnetic energy storage and phase shifter, is proposed to improve the stability of a long distance bulk power transmission system. A power system stabilizing control scheme is also proposed. A related simulation shows that the proposed controller is effective for enhancement of power system stability

  3. a Study of the Heat Transfer Characteristics during Cool-Down of a 1.5 T Superconducting MRI Magnet

    NASA Astrophysics Data System (ADS)

    Zia, J.; Wexler, E.

    2010-04-01

    One of the steps in the manufacture of a superconducting MRI magnet involves cool down of the magnet cryostat from room temperature to 4.2 K before it can be filled with liquid helium. The primary source for refrigeration in this process is cryogenic temperature helium gas that is injected into an inlet port in the cryostat and recovered at the outlet port. During normal clinical use, the electromagnetic forces generated by the magnet are extremely high. The design of the cryostat is therefore aimed at supporting the structural and electromagnetic requirements of the magnet at the expense of heat transfer efficiency during cool down. As a result, the cool down process may be inefficient leading to loss and expense of cryogenic helium. The aim of this work is to evaluate this potential inefficiency by experimentally measuring temperature distribution and heat transfer characteristics of a typical GE 1.5 T magnet to refine and validate a CFD model of the cryostat.

  4. Full-power test of a string of magnets comprising a half-cell of the Superconducting Super Collider

    SciTech Connect

    Burgett, W.; Christianson, M.; Coombes, R. [and others

    1992-10-01

    In this paper we describe the full-powered operation of a string of industrially-fabricated magnets comprising a half-cell of the Superconducting Super Collider (SSC). The completion of these tests marks the first successful operation of a major SSC subsystem. The five 15-m long dipole magnets in the string had an aperture of 50 mm and the single 5-m long quadrupole aperture was 40 mm. Power and cryogenic connections were made to the string through spool pieces that are prototypes for SSC operations. The string was cooled to cryogenic temperatures in early July, 1992, and power tests were performed at progressively higher currents up to the nominal SSC operating point above 6500 amperes achieved in mid-August. In this paper we report on the electrical and cryogenic performance of the string components and the quench protection system during these initial tests.

  5. Uniform temperature cooling power of the superfluid stirling refrigerator

    SciTech Connect

    Watanabe, A.; Brisson, J.G. [Massachusetts Inst. of Technology, Cambridge, MA (United States); Swift, G.W. [Los Alamos National Laboratory, NM (United States)

    1996-06-01

    Uniform temperature cooling power measurements of a superfluid Stirling refrigerator are presented for {sup 3}He-{sup 4}He molar concentrations of 5.9%, 17% and 36% and for temperatures between 0.37 K and 1.4 K. The results are compared to an ideal Fermi gas model and to a more general thermodynamic model. The Fermi model agrees well with the 5.9% concentration data; however, the more elaborate model is needed for higher concentration mixtures.

  6. Exergy analysis of solar Rankine power cycles used for cooling

    Microsoft Academic Search

    Lior; W. J. Brady

    1983-01-01

    Second-law (exergy) analysis was performed on two types of solar-cooling systems which are based on a vapor-compression cycle driven by a Rankine cycle: those energized by the sun at one temperature and using organic fluids in the power cycle, and a hybrid cycle which is energized by a solar source at a low temperature and by a fossil source at

  7. Design of the fundamental power coupler and photocathode inserts for the 112MHz superconducting electron gun

    SciTech Connect

    Xin, T.; Ben-Zvi, I.; Belomestnykh, S.; Chang, X.; Rao, T.; Skaritka, J.; Wu, Q.; Wang, E.; Liang, X.

    2011-07-25

    A 112 MHz superconducting quarter-wave resonator electron gun will be used as the injector of the Coherent Electron Cooling (CEC) proof-of-principle experiment at BNL. Furthermore, this electron gun can be the testing cavity for various photocathodes. In this paper, we present the design of the cathode stalks and a Fundamental Power Coupler (FPC) designated to the future experiments. Two types of cathode stalks are discussed. Special shape of the stalk is applied in order to minimize the RF power loss. The location of cathode plane is also optimized to enable the extraction of low emittance beam. The coaxial waveguide structure FPC has the properties of tunable coupling factor and small interference to the electron beam output. The optimization of the coupling factor and the location of the FPC are discussed in detail. Based on the transmission line theory, we designed a half wavelength cathode stalk which significantly brings down the voltage drop between the cavity and the stalk from more than 5.6 kV to 0.1 kV. The transverse field distribution on cathode has been optimized by carefully choosing the position of cathode stalk inside the cavity. Moreover, in order to decrease the RF power loss, a variable diameter design of cathode stalk has been applied. Compared to the uniform shape of stalk, this design gives us much smaller power losses in important locations. Besides that, we also proposed a fundamental power coupler based on the designed beam parameters for the future proof-of-principle CEC experiment. This FPC should give a strong enough coupling which has the Q external range from 1.5e7 to 2.6e8.

  8. High power rapidly tunable system for laser cooling

    NASA Astrophysics Data System (ADS)

    Gomez, Eduardo; Valenzuela Jimenez, Victor Manuel; Hernandez Diaz, Lorenzo

    2012-06-01

    Laser cooling experiments require light sources that can be rapidly tuned in frequency and power. Keeping as much power as possible increases the number of trapped atoms. We present a configuration that combines the capabilities of rapid frequency tuning with power amplification in a robust system. A double pass acousto-optic modulator (AOM) changes the frequency of the laser beam while keeping the alignment approximately constant. We decouple the modulation and amplification sections using an optical fiber and we keep the power out of the fiber constant by feed-forward on the amplitude modulation of the AOM. The tapered amplifier is in a double pass configuration and requires an input of only 1 mW to obtain 1 W out. A second modulator controls the intensity after the amplifier and generates additional beams that we use, for example, to do absorption imaging. We demonstrate the transfer of atoms to a dipole trap using the system.

  9. Power plant cooling system water consumption and nonwater impact reports. Executive summary August 1979-April 1981

    SciTech Connect

    Hu, M.C.; Pavlenco, G.F.; Englesson, G.A.

    1981-07-01

    Water evaporation and consumption of power plant cooling systems were studied and six simple generic evaporation prediction models were evaluated, one for cooling towers and five for cooling ponds/lakes using field data provided by twelve utilities. Also evaluated in the study is a regional comparison of evaporation rates of cooling towers and cooling ponds/lakes with the objective of determining which of the two cooling system types is more water consumptive in terms of evaporation only.

  10. A gas-cooled reactor surface power system

    NASA Astrophysics Data System (ADS)

    Lipinski, Ronald J.; Wright, Steven A.; Lenard, Roger X.; Harms, Gary A.

    1999-01-01

    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 nitride clad in Nb1%Zr, which has been extensively tested under the SP-100 program. The fuel rods are arranged in a hexagonal array within a BeO block. The BeO softens the spectrum, allowing better use of the fuel and stabilizing the geometry 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 can not occur for any launch accident. This system is also adaptable for electric propulsion or life-support during transit to and from Mars.

  11. Enhanced magnetic anomaly detection using a nitrogen-cooled superconducting gradiometer

    Microsoft Academic Search

    Ted R. Clem; David J. Overway; John W. Purpura; John T. Bono; Paul J. Carroll; Roger H. Koch; James R. Rozen; George A. Keefe; Scott Willen; Robert A. Mohling

    2000-01-01

    During the 1980's the Superconducting Gradiometer\\/Magnetometer Sensor was demonstrated in the Magnetic and Acoustic Detection of Mines Advanced Technology Demonstration to provide effective mine detection, localization, and classification capabilities, especially against buried mines, and to reduce significantly acoustic false alarms arising from bottom clutter. This sensor utilized Superconducting Quantum Interference Devices manufactured using the low critical temperature (low Tc) superconductor

  12. Performance of a power conversion system for superconducting magnetic energy storage (SMES)

    Microsoft Academic Search

    James J. Skiles; Robert L. Kustom; Ka-Pui Ko; V. Wong; Ka-Shu Ko; F. Vong; K. Klontz

    1996-01-01

    This paper presents the results of laboratory tests of a power conversion system (PCS) for superconducting magnetic energy storage (SMES) applications. The PCS uses a two-quadrant chopper and a voltage-source power converter. Operating modes of the chopper are discussed. Operation of SMES to provide independent control of real and reactive power, operation as a static VAr compensator, low frequency modulation

  13. Solar-powered Rankine heat pump for heating and cooling

    NASA Technical Reports Server (NTRS)

    Rousseau, J.

    1978-01-01

    The design, operation and performance of a familyy of solar heating and cooling systems are discussed. The systems feature a reversible heat pump operating with R-11 as the working fluid and using a motor-driven centrifugal compressor. In the cooling mode, solar energy provides the heat source for a Rankine power loop. The system is operational with heat source temperatures ranging from 155 to 220 F; the estimated coefficient of performance is 0.7. In the heating mode, the vapor-cycle heat pump processes solar energy collected at low temperatures (40 to 80 F). The speed of the compressor can be adjusted so that the heat pump capacity matches the load, allowing a seasonal coefficient of performance of about 8 to be attained.

  14. New cryocooler-cooled superconducting magnet: A 13.5 T high-field split-pair coil magnet for neutron scattering

    Microsoft Academic Search

    S. Katano; N. Minakawa; T. Hasebe; J. Sakuraba

    2006-01-01

    A new high-field superconducting magnet of the cryogen-free type has been developed. The superconducting coil of this system is directly cooled down by three 4 K-GM cryocoolers. The magnet consists of a split-pair of (Nb,Ti)3Sn inner coils and NbTi outer ones; and its outer diameter is 545mm and the height is 352mm. The gap for the beam path is 18mm

  15. 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

  16. NQR study of local structures and cooling rate dependent superconductivity in La sub 2 CuO sub 4+. delta

    SciTech Connect

    Reyes, A.P.; Ahrens, E.T.; Hammel, P.C.; Heffner, R.H.; Thompson, J.D.; Canfield, P.C.; Fisk, Z. (Los Alamos National Lab., NM (United States)); Schirber, J.E. (Sandia National Labs., Albuquerque, NM (United States))

    1992-01-01

    Structural properties of oxygen-annealed polycrystals of La{sub 2}CuO{sub 4 + {delta}} ({delta}{approximately}0.03) have been studied using {sup 139}La NQR spectroscopy. Superconducting critical temperatures were found to depend on the rate of cooling through a narrow temperature range at about 195K. Preliminary analysis of the {sup 139}La NQR spectra suggest that the oxygen-rich phase-separated region is composed of two structurally distinct phases, both of which are metallic and super-conducting. One phase has a structure closely related to the stoichiometric oxygen-poor compound. The second shows a considerable amount of apical oxygen disorder, a large shift in NQR frequency {nu}{sub Q}, and a volume fraction which increases with cooling rate. The formation of the second phase below {minus}200K is indicative of the freezing Of CuO{sub 6} octahedral tilting. Abrupt shifts in {nu}{sub Q} above {Tc} were also observed for both phases, suggestive of a local structural anomaly or charge transfer to the Cu-O plane.

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

    SciTech Connect

    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

    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.

  18. Cold side thermal energy storage system for improved operation of air cooled power plants

    E-print Network

    Williams, Daniel David

    2012-01-01

    Air cooled power plants experience significant performance fluctuations as plant cooling capacity reduces due to higher daytime temperature than nighttime temperature. The purpose of this thesis is to simulate the detailed ...

  19. Power Conversion Study for High Temperature Gas-Cooled Reactors

    SciTech Connect

    Chang Oh; Richard Moore; Robert Barner

    2005-05-01

    The Idaho National Laboratory (INL) is investigating a Brayton cycle efficiency improvement on a high temperature gas-cooled reactor (HTGR) as part of Generation-IV nuclear engineering research initiative. There are some technical issues to be resolved before the selection of the final design of the high temperature gascooled reactor, called as a Next Generation Nuclear Plant (NGNP), which is supposed to be built at the INEEL by year 2017. The technical issues are the selection of the working fluid, direct vs. indirect cycle, power cycle type, the optimized design in terms of a number of intercoolers, and others. In this paper, we investigated a number of working fluids for the power conversion loop, direct versus indirect cycle, the effect of intercoolers, and other thermal hydraulics issues. However, in this paper, we present part of the results we have obtained. HYSYS computer code was used along with a computer model developed using Visual Basic computer language.

  20. Insulation design of cryogenic bushing for superconducting electric power applications

    NASA Astrophysics Data System (ADS)

    Koo, J. Y.; Lee, Y. J.; Shin, W. J.; Kim, Y. H.; Kim, J. T.; Lee, B. W.; Lee, S. H.

    2013-01-01

    Recently, the superconductivity projects to develop commercial superconducting devices for extra high voltage transmission lines have been undergoing in many countries. One of the critical components to be developed for high voltage superconducting devices, including superconducting transformers, cables, and fault current limiters, is a high voltage bushing, to supply high current to devices without insulating difficulties, that is designed for cryogenic environments. Unfortunately, suitable bushings for HTS equipment were not fully developed for some cryogenic insulation issues. Such high voltage bushings would need to provide electrical insulation capabilities from room temperature to cryogenic temperatures. In this paper, design factors of cryogenic bushings were discussed and test results of specimen were introduced in detail. First, the dielectric strength of three kinds of metals has been measured with uniform and non-uniform electrodes by withstand voltage of impulse and AC breakdown test in LN2. Second, puncture breakdown voltage of glass fiber reinforced plastics (GFRPs) plates has been analyzed with non-uniform electrodes. Finally, creepage discharge voltages were measured according to the configuration of non-uniform and uniform electrode on the FRP plate. From the test results, we obtained the basic design factors of extra high voltage condenser bushing, which could be used in cryogenic environment.

  1. RF design and processing of a power coupler for third harmonic superconducting cavities

    SciTech Connect

    Li, Jianjian; Harms, Elvin; Kubicki, Tom; Nicklaus, Dennis; Olis, Daniel; Prieto, Peter; Reid, John; Solyak, Nikolay; /Fermilab; Wong, Thomas; /IIT, Chicago

    2007-06-01

    The FLASH user facility providing free electron laser radiation is built based on the TTF project at DESY. Fermilab has the responsibility for the design and processing of a third harmonic, 3.9 GHz, superconducting cavity which is powered via a coaxial power coupler. Six power couplers have been manufactured at CPI after successful design of the power coupler including RF simulation, multipacting calculation, and thermal analysis. The power couplers are being tested and processed with high pulsed power in an elaborate test stand at Fermilab now. This paper presents the RF design and processing work of the power coupler.

  2. Non-Cooled Power System for Venus Lander

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

    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.

  3. Development of superconducting magnet with low electric power loss for SMES

    Microsoft Academic Search

    K. Hayakawa; T. Nakano; M. Minami; M. Fujiwara; T. Kanzawa; S. Terai; E. Haraguchi; A. Ryouman; Y. Murakami

    1993-01-01

    A superconducting magnet with a 0.01% electric power loss was developed. This magnet is used to store electric power as magnetic energy and to stabilize an electric power system. This magnet of 78-cm outer diameter and 27-cm width consists of 18 double-pancake-type coils and was designed with a 10-T\\/s pulse-discharge speed and 350-A transportation current. To reduce energy loss caused

  4. Development of REBCO superconducting power transformers in Japan

    NASA Astrophysics Data System (ADS)

    Iwakuma, M.; Hayashi, H.; Okamoto, H.; Tomioka, A.; Konno, M.; Saito, T.; Iijima, Y.; Suzuki, Y.; Yoshida, S.; Yamada, Y.; Izumi, T.; Shiohara, Y.

    2009-10-01

    In Japan we started a national project to develop a 66/6.9 kV-20 MVA transformer with REBCO superconducting tapes in 2006. This paper gives an overview of progress of the development of superconducting transformers in Japan and also describes the fundamental technologies studied before now to realize a 66/6.9 kV-20 MVA transformer as follows. To reduce the ac loss in REBCO superconducting thin tapes, authors proposed a new method different from the conventional technique of reducing the ac loss in superconducting multifilamentary wires. It consists of scribing process into a multifilamentary structure by laser or chemical etching, and a special winding process. Making a multilayered solenoidal coil with laser-scribed REBCO tapes, we verified the ac loss reduction in proportion to a filament width even in coil configuration. In addition, to realize a current capacity more than the rated secondary current of 2.4 kA, we first investigated the workability of REBCO tapes in the actual winding process with forming a transposed parallel conductor, where REBCO tapes were bent edgewise at transposing points. Making a test coil of a 24-strand parallel conductor, we verified no degradation of the critical current and nearly uniform current distribution among the tapes. The result suggests the applicability of the method of enhancing the current capacity by forming a parallel conductor with REBCO tapes. Further, to realize the dielectric strength regulated for the Japanese standards, i.e. lightning impulse withstand level of 350 kV and excess ac voltage of 140 kV, we made test coils and carried out dielectric breakdown tests. As a result, we got hold of the required insulation distance at the important points from the viewpoint of insulation design.

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

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

    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.

  6. Air-cycle cooling of electric power cables: Phase I. Final report

    Microsoft Academic Search

    Limberg

    1981-01-01

    A study was conducted to determine the feasibility of using an air cycle system for cooling underground electrical power transmission cables. The air cycle system features an expansion turbine where ambient air is expanded to subatmospheric pressure; this air is circulated in a plate fin heat exchanger and cools the cable dielectric oil. The cooling capacity of the low pressure

  7. The Cost of Helium Refrigerators and Coolers for SuperconductingDevices as a Function of Cooling at 4 K

    SciTech Connect

    Green, Michael A.

    2007-08-27

    This paper is an update of papers written in 1991 and in1997 by Rod Byrns and this author concerning estimating the cost ofrefrigeration for superconducting magnets and cavities. The actual costsof helium refrigerators and coolers (escalated to 2007 dollars) areplotted and compared to a correlation function. A correlation functionbetween cost and refrigeration at 4.5 K is given. The capital cost oflarger refrigerators (greater than 10 W at 4.5 K) is plotted as afunction of 4.5-K cooling. The cost of small coolers is plotted as afunction of refrigeration available at 4.2 K. A correlation function forestimating efficiency (percent of Carnot) of both types of refrigeratorsis also given.

  8. Testing of a Liquid Nitrogen Cooled 5-meter, 3000 A Tri-Axial High Temperature Superconducting Cable System

    NASA Astrophysics Data System (ADS)

    Demko, J. A.; Duckworth, R. C.; Fisher, P. W.; Gouge, M. J.; Rey, C. M.; Young, M. A.; Lindsay, D.; Roden, M.; Tolbert, J.; Willen, D.; Træholt, C.; Thidemann, C.

    2006-04-01

    The tri-axial HTS cable design uses three concentric superconducting layers for the phase conductors separated by a cold dielectric material. It offers an efficient HTS cable configuration by reducing the amount of superconductor needed, and placing all three phases in a single cryostat. Ultera and ORNL tested a 5-meter long tri-axial HTS cable and terminations designed to operate at 3 kA ac and 13.2 kV. Test results, including the thermal loads on the system, will be reported. An existing liquid nitrogen skid that circulates subcooled liquid nitrogen through the cable was initially designed for the heat loads on single phase cables at lower current ratings. The refrigeration needed for the 3 kA tri-axial cable configuration made it necessary to upgrade the nitrogen system to increase the cooling capacity. A description of the upgrades and performance of the system is provided.

  9. Introduction to progress and promise of superconductivity for energy storage in the electric power sector

    SciTech Connect

    Wolsky, A.M.

    1998-05-01

    Around the world, many groups conduct research, development and demonstration (RD and D) to make storage an economic option for the electric power sector. The progress and prospects for the application of superconductivity, with emphasis on 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, Korea, the Netherlands, Norway, Sweden, Switzerland, Turkey, the United Kingdom and the US. 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 informtion among experts in all countries and has documented relevant assessments. Further, this work has reviewed the status of SMES and is now updating same, as well as investigating the progress on and prospects for flywheels with superconducting bearings. The Operating Agent and Task members find a substantially different set of opportunities for and alternatives to storage than was the case before the 1987 discovery of high-temperature superconductivity. Beside the need to level generation, there is also the need to level the load on transmission lines, increase transmission stability, and increase power quality. These needs could be addressed by high power storage that could be brought in and out of the grid in fractions of a second. Superconducting Magnetic Energy Storage and flywheels with superconducting bearings are devices that deserve continued RD and D because they promise to be the needed storage devices.

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

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    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.

  11. Forced cooling of underground electric power transmission lines : design manual

    E-print Network

    Brown, Jay A.

    1978-01-01

    The methodology utilized for the design of a forced-cooled pipe-type underground transmission system is presented. The material is divided into three major parts: (1) The Forced-cooled Pipe-Type Underground Transmission ...

  12. Gas-cooled reactor for space power systems

    SciTech Connect

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

    1987-05-01

    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.

  13. Concepts and methods of refrigeration for superconducting power transmission cables. Final report

    Microsoft Academic Search

    S. A. Manatt; P. G. Wapato; J. Stanko; J. P. Baumgartner

    1976-01-01

    An analysis of refrigeration system requirements for the superconducting power transmission cables currently under study at the three principal US cable development centers indicates the need for cable system design considering the interrelated performance of the various cable system elements to successfully develop these systems for commercial operation in the 1990's. Hardware alternatives, compatible with the application timeframe, are evaluated

  14. Installation and operation of the Southwire 30-meter high-temperature superconducting power cable

    Microsoft Academic Search

    J. P. Stovall; J. A. Demko; P. W. Fisher; M. J. Gouge; J. W. Lue; U. K. Sinha; J. W. Armstrong; R. L. Hughey; D. Lindsay; J. C. Tolbert

    2001-01-01

    Southwire Company has installed, tested and is operating the first real-world application of a high-temperature superconducting cable system at its headquarters in Carrollton, GA, USA. The cable is powering three Southwire manufacturing plants, marking the first time a company has successfully made the difficult transition front laboratory to practical field application of an HTS cable. The cables are rated at

  15. Pathogenic amoebae in power-plant cooling lakes. Final report

    SciTech Connect

    Tyndall, R.L.; Willaert, E.; Stevens, A.R.

    1981-06-01

    Cooling waters and associated algae and sediments from four northern and four southern/western electric power plants were tested for the presence of pathogenic amoebae. Unheated control waters and algae/sediments from four northern and five southern/western sites were also tested. When comparing results from the test versus control sites, a significantly higher proportion (P less than or equal to 0.05) of the samples from the test sites were positive for thermophilic amoeba, thermophilic Naegleria and pathogenic Naegleria. The difference in number of samples positive for thermophilic Naegleria between heated and unheated waters, however, was attributable predominantly to the northern waters and algae/sediments. While two of four northern test sites yielded pathogenic Naegleria, seven of the eight isolates were obtained from one site. Seasonality effects relative to the isolation of the pathogen were also noted at this site. One pathogen was isolated from a southwestern test site. Pathogens were not isolated from any control sites. Some of the pathogenic isolates were analyzed serologically and classified as pathogenic Naegleria fowleri. Salinity, pH, conductivity, and bacteriological profiles did not obviously correlate with the presence or absence of pathogenic Naegleria. While thermal addition was significantly associated with the presence of thermophilic Naegleria (P less than or equal to 0.05), the data implicate other as yet undefined parameters associated with the presence of the pathogenic thermophile. Until further delineation of these parameters is effected, generalizations cannot be made concerning the effect of thermal impact on the growth of pathogenic amoeba in a particular cooling system.

  16. Site-dependent factors affecting the economic feasibility of solar powered absorption cooling

    NASA Technical Reports Server (NTRS)

    Bartlett, J. C.

    1977-01-01

    A procedure has been developed which can be used to determine the economic feasibility of solar powered absorption cooling systems. This procedure has been used in a study to investigate the influence of the site-dependent parameters on the economic feasibility of solar absorption cooling. The purpose of this study was to make preliminary site selections for solar powered absorption cooling systems. This paper summarizes the results of that study.

  17. Commissioning tests of the Bonneville Power Administration 30 MJ superconducting magnetic energy storage unit

    NASA Astrophysics Data System (ADS)

    Boening, H. J.; Hauer, J. F.

    A 30 MJ (8.4 kWh) Superconducting Magnetic Energy Storage (SMES) unit with a 10 MW converter was 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 of energy at a frequency of 0.35 Hz, was designed to damp the dominant power swing mode of the Pacific AC Intertie. The electrical characteristics of the magnetic energy storage unit, its modes of operation, results of device tests, means for controlling real and reactive power, and some initial power system response tests are described. A short summary of the operating history of the unit over the first eleven months is also presented.

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

    Microsoft Academic Search

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

    2011-01-01

    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

  19. Experimental results on the free cooling power available on 4K pulse tube coolers

    E-print Network

    Boyer, Edmond

    Experimental results on the free cooling power available on 4K pulse tube coolers T Prouv´e1, H on the free cooling power available at the level of the second stage regenerator of a 4K pulse tube cooler and the pulse tube stages under different distributions of the total heat load. 1. Introduction In order

  20. Environmental Problems Associated with Decommissioning of Chernobyl Power Plant Cooling Pond

    Microsoft Academic Search

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

    2009-01-01

    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

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

    Microsoft Academic Search

    Jiangfeng Wang; Yiping Dai; Lin Gao; Shaolin Ma

    2009-01-01

    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

  2. Space power reactor ground test in the Experimental Gas Cooled Reactor (EGCR) at Oak Ridge

    Microsoft Academic Search

    M. H. Fontana; R. S. Holcomb; R. H. Cooper

    1992-01-01

    The Experimental Gas Cooled Reactor (EGCR) facility and the supporting technical infrastructure at the Oak Ridge National Laboratory have the capabilities of performing ground tests of space nuclear power reactor systems. A candidate test would be a 10 MWt lithium cooled reactor, generating potassium vapor that would drive a power turbine. The facility is a large containment vessel originally intended

  3. High-temperature superconducting microstrip filters with high power-handling capability

    Microsoft Academic Search

    G.-C. Liang; D. Zhang; C.-F. Shih; M. E. Johansson; R. Withers; A. C. Anderson; D. E. Oates; P. Polakos; P. Mankiewich; E. de Obaldia; R. E. Miller

    1995-01-01

    The performance of narrowband microstrip filters with low insertion loss and high power-handling capabilities made from YBa2 Cu3O7 (YBCO) high-temperature superconducting (HTS) films is presented. Results are shown for two different novel designs that were chosen to optimize the power-handling capabilities. Both have a 2-GHz center frequency and 5-poles that incorporate coupled resonators with 10-? internal impedances on 50-mm-diameter LaAlO3

  4. At the Frontiers of Science Superconductivity and Its Electric Power Applications

    SciTech Connect

    None

    1998-07-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

    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.

  6. Fabrication of a diffusion cooled superconducting hot electron bolometer for THz mixing applications

    Microsoft Academic Search

    Bruce Bumble; Henry G. LeDuc

    1997-01-01

    Recent interest in bolometers for heterodyne mixing applications has prompted development of microbridges which are small enough to allow electron diffusion to dominate over electron-phonon interaction as a cooling mechanism. Prior results at 533 GHz have demonstrated several GHz intermediate frequency (IF) bandwidth. Here we describe our processing method in which the bolometer element is a 10 nm thin film

  7. Simulation of multiple stability regions in an internally cooled superconducting conductor with the computer code SSICC

    SciTech Connect

    Turner, L.R.; Shindler, J.

    1984-08-01

    The computer code SSICC (Safety and Stability of Internally Cooled Conductors) has successfully simulated the multiple stability regions observed experimentally by Lue, Miller, and Dresner of Oak Ridge National Laboratory. The simulation requires asymmetrical boundary conditions and a heating pulse duration short compared to the time for reflection of the transient pressure wave back into the heated region of the conductor.

  8. Spray cooling characteristics of nanofluids for electronic power devices

    NASA Astrophysics Data System (ADS)

    Hsieh, Shou-Shing; Leu, Hsin-Yuan; Liu, Hao-Hsiang

    2015-03-01

    The performance of a single spray for electronic power devices using deionized (DI) water and pure silver (Ag) particles as well as multi-walled carbon nanotube (MCNT) particles, respectively, is studied herein. The tests are performed with a flat horizontal heated surface using a nozzle diameter of 0.5 mm with a definite nozzle-to-target surface distance of 25 mm. The effects of nanoparticle volume fraction and mass flow rate of the liquid on the surface heat flux, including critical heat flux (CHF), are explored. Both steady state and transient data are collected for the two-phase heat transfer coefficient, boiling curve/ cooling history, and the corresponding CHF. The heat transfer removal rate can reach up to 274 W/cm2 with the corresponding CHF enhancement ratio of 2.4 for the Ag/water nanofluids present at a volume fraction of 0.0075% with a low mass flux of 11.9 × 10-4 kg/cm2s.

  9. Mechanical Analysis of High Power Internally Cooled Annular Fuel

    SciTech Connect

    Zhao Jiyun; No, Hee Cheon; Kazimi, Mujid S. [Center for Advanced Nuclear Energy Systems (United States)

    2004-05-15

    Annular fuel with internal flow is proposed to allow higher power density in pressurized water reactors. The structural behavior issues arising from the higher flow rate required to cool the fuel are assessed here, including buckling, vibrations, and potential wear problems. Five flow-induced vibration mechanisms are addressed: buckling instability, vortex-induced vibration, acoustic resonance, fluid-elastic instability, and turbulence-induced vibration. The structural behavior of the 17 x 17 traditional solid fuel array is compared with that of two types of annular fuels, a 15 x 15 array, and a 13 x 13 array.It is seen that the annular fuels are superior to the reference fuel in avoiding vibration-induced damage, even at a 50% increase in flow velocity above today's reactors. The higher resistance to vibration is mainly due to their relatively larger cross section area making them more rigid. The 13 x 13 annular fuel shows better structural performance than the 15 x 15 one due to its higher rigidity. Analysis of acoustic resonance of the inner channel cladding with pump blade passing frequencies showed that the acoustic frequencies are within 120% of the pulsation frequency. The annular fuel exhibits reduced impact, sliding, and fretting wear than the solid fuel, even at 150% flow rate of today's reactors.

  10. Spray cooling characteristics of nanofluids for electronic power devices.

    PubMed

    Hsieh, Shou-Shing; Leu, Hsin-Yuan; Liu, Hao-Hsiang

    2015-01-01

    The performance of a single spray for electronic power devices using deionized (DI) water and pure silver (Ag) particles as well as multi-walled carbon nanotube (MCNT) particles, respectively, is studied herein. The tests are performed with a flat horizontal heated surface using a nozzle diameter of 0.5 mm with a definite nozzle-to-target surface distance of 25 mm. The effects of nanoparticle volume fraction and mass flow rate of the liquid on the surface heat flux, including critical heat flux (CHF), are explored. Both steady state and transient data are collected for the two-phase heat transfer coefficient, boiling curve/ cooling history, and the corresponding CHF. The heat transfer removal rate can reach up to 274 W/cm(2) with the corresponding CHF enhancement ratio of 2.4 for the Ag/water nanofluids present at a volume fraction of 0.0075% with a low mass flux of 11.9?×?10(-4) kg/cm(2)s. PMID:25852429

  11. Remote Measurement of Heat Flux from Power Plant Cooling Lakes

    SciTech Connect

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

    2013-01-01

    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.

  12. Experimental study on active cooling systems used for thermal management of high-power multichip light-emitting diodes.

    PubMed

    Kaya, Mehmet

    2014-01-01

    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

  13. The impact of high temperature superconductivity on the electric power sector

    SciTech Connect

    Wolsky, A.M.

    1996-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  15. Sub-cooled liquid nitrogen cryogenic system with neon turbo-refrigerator for HTS power equipment

    NASA Astrophysics Data System (ADS)

    Yoshida, S.; Hirai, H.; Nara, N.; Ozaki, S.; Hirokawa, M.; Eguchi, T.; Hayashi, H.; Iwakuma, M.; Shiohara, Y.

    2014-01-01

    We developed a prototype sub-cooled liquid nitrogen (LN) circulation system for HTS power equipment. The system consists of a neon turbo-Brayton refrigerator with a LN sub-cooler and LN circulation pump unit. The neon refrigerator has more than 2 kW cooling power at 65 K. The LN sub-cooler is a plate-fin type heat exchanger and is installed in a refrigerator cold box. In order to carry out the system performance tests, a dummy cryostat having an electric heater was set instead of a HTS power equipment. Sub-cooled LN is delivered into the sub-cooler by the LN circulation pump and cooled within it. After the sub-cooler, sub-cooled LN goes out from the cold box to the dummy cryostat, and comes back to the pump unit. The system can control an outlet sub-cooled LN temperature by adjusting refrigerator cooling power. The refrigerator cooling power is automatically controlled by the turbo-compressor rotational speed. In the performance tests, we increased an electric heater power from 200 W to 1300 W abruptly. We confirmed the temperature fluctuation was about ±1 K. We show the cryogenic system details and performance test results in this paper.

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

    SciTech Connect

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

    1982-10-01

    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.

  17. Engineering development of superconducting RF linac for high-power applications

    SciTech Connect

    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

    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.

  18. Advanced superconducting MHD magnet design for a retrofit power plant

    Microsoft Academic Search

    P. G. Marston; J. R. Hale; A. M. Dawson

    1989-01-01

    A magnet system has been designed for an MHD topping cycle retrofit of a conventional power plant. The channel power output wil be --35 MWe. The 4.5 T peak on-axis field magnet will be constructed of an unusual NbTi superconductor wound into four subunits per dipole half. These will be three 45° saddle coils with circular or ellipsoidal end turns

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

    SciTech Connect

    None

    2010-10-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

    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.

  1. Self-cooling on power MOSFET using n-type Si wafer

    NASA Astrophysics Data System (ADS)

    Nakatsugawa, H.; Sato, T.; Okamoto, Y.; Kawahara, T.; Yamaguchi, S.

    2012-06-01

    The self-cooling device was developed by combining the commercial n-channel power MOSFET and the copper plating single-crystalline Sb doped n-type silicon wafer in order to improve heat removal or cooling for power devices. The time dependence of the temperature distribution of the self-cooling device was measured to estimate the heat flux both by the thermal conduction and by the Peltier effect. We found that the average temperature of the upper side of the power MOSFET was cooled down about 0.7°C by the addition of the copper plating n-type Si wafer after 40 minutes despite enlargement of the temperature distribution range. This fact strongly indicates that the copper plating ntype Si wafer is one of the candidate materials for use in self-cooling devices.

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

    DOEpatents

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

    1982-07-29

    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.

  3. Performance test of current lead cooled by a cryocooler in low temperature superconducting magnet system

    NASA Astrophysics Data System (ADS)

    Choi, Yeon Suk; Kim, Myung Su

    2013-11-01

    In a low temperature superconducting magnet system, heat leakage through current leads is one of the major factors in cryogenic load. The semi-retractable current lead is a good option because the conductive heat leakage can be eliminated after the excitation of the magnet. It is composed of a normal metal element, conducting the current from room temperature to intermediate temperature, and an HTS element, conducting the current down to liquid helium temperature. The normal metal element is disengaged from the HTS element through the multi-contact connector without disturbance to the insulating vacuum space and without requiring complete removal of the normal metal element. The intermediate block with a lockable set point is thermally connected to the first stage of cryocooler and carries current through a strip of louvered material. The electrical contact resistance of multi-contact connector in the intermediate block is measured during magnet charging process. The effects of current level as well as operating temperature on the heat generation in the joint block are also discussed.

  4. Development of 275kV gas cooled type gas-insulated power transformer

    Microsoft Academic Search

    A. Kudo; T. Nishitani; T. Yoshikawa; C. T. Wan

    1993-01-01

    A world's first 275kV gas cooled type gas insulated power transformer with a low sound level ideal for urban area, which depends on SF6 gas alone for both insulation and cooling, was developed and has been put into commercial service since 1990 in Hong Kong. This paper presents the design philosophy, the principal technical items, the rating and the feature

  5. 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...

  6. Thermal Management of Power Semiconductor Packages - Matching Cooling Technologies with Packaging Technologies (Presentation)

    Microsoft Academic Search

    K. Bennion; G. Moreno

    2010-01-01

    Heat removal for power semiconductor devices is critical for robust operation. Because there are different packaging options, different thermal management technologies, and a range of applications, there is a need for a methodology to match cooling technologies and package configurations to target applications. To meet this need, a methodology was developed to compare the sensitivity of cooling technologies on the

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

    SciTech Connect

    Shishlo, Andrei P [ORNL

    2014-01-01

    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

  8. The effect of operating temperature and turbine blade cooling on Brayton cycle space power systems

    Microsoft Academic Search

    Michael W. Edenburn

    1988-01-01

    Systems analyses were performed to evaluate multimegawatt (MMW) space power systems and to help determine which areas of technical development should receive emphasis. Results are presented from a part of the system evaluation work that deals with MMW, Brayton cycle, and space power systems. How turbine inlet temperature and turbine blade cooling affect the mass of a Brayton space power

  9. 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 ...

  10. 100 W-output power from passively cooled laser bar with 30% filling factor

    Microsoft Academic Search

    A. Knigge; G. Erbert; P. Ressel; B. Sumpf; H. Wenzel; G. Trankle

    2004-01-01

    940 nm laser bars with optimised layer structures will be reported. 100 W output power, wall plug efficiency above 60% and a vertical divergence of 27° FWHM were achieved despite mounting on passively cooled heat sinks only.

  11. Energy Efficiency Evaluation of Refrigeration Technologies in Combined Cooling, Heating and Power Systems 

    E-print Network

    Zuo, Z.; Hu, W.

    2006-01-01

    ICEBO2006, Shenzhen, China Building Commi ssioning for Energy Efficiency and Comfort, Vol.VI-7-3 Energy Efficiency Evaluation of Refrigeration Technologies in Combined Cooling, Heating and Power Systems Zheng Zuo WenBin Hu...

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

    NASA Astrophysics Data System (ADS)

    Wu, Jinglin; Long, Jiaojiao; Liu, Xiaoning

    2014-09-01

    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.

  13. Cryogenics Vision Workshop for High-Temperature Superconducting Electric Power Systems Proceedings

    SciTech Connect

    Energetics, Inc.

    2000-01-01

    The US Department of Energy's Superconductivity Program for Electric Systems sponsored the Cryogenics Vision Workshop, which was held on July 27, 1999 in Washington, D.C. This workshop was held in conjunction with the Program's Annual Peer Review meeting. Of the 175 people attending the peer review meeting, 31 were selected in advance to participate in the Cryogenics Vision Workshops discussions. The participants represented cryogenic equipment manufactures, industrial gas manufacturers and distributors, component suppliers, electric power equipment manufacturers (Superconductivity Partnership Initiative participants), electric utilities, federal agencies, national laboratories, and consulting firms. Critical factors were discussed that need to be considered in describing the successful future commercialization of cryogenic systems. Such systems will enable the widespread deployment of high-temperature superconducting (HTS) electric power equipment. Potential research, development, and demonstration (RD and D) activities and partnership opportunities for advancing suitable cryogenic systems were also discussed. The workshop agenda can be found in the following section of this report. Facilitated sessions were held to discuss the following specific focus topics: identifying Critical Factors that need to be included in a Cryogenics Vision for HTS Electric Power Systems (From the HTS equipment end-user perspective) identifying R and D Needs and Partnership Roles (From the cryogenic industry perspective) The findings of the facilitated Cryogenics Vision Workshop were then presented in a plenary session of the Annual Peer Review Meeting. Approximately 120 attendees participated in the afternoon plenary session. This large group heard summary reports from the workshop session leaders and then held a wrap-up session to discuss the findings, cross-cutting themes, and next steps. These summary reports are presented in this document. The ideas and suggestions raised during the Workshop will be used by the DOE Superconductivity Program for Electric Systems in preparing subsequent planning and strategy documents such as a Cryogenic Technology Development Roadmap.

  14. Analysis of power and cooling cogeneration using ammonia-water mixture

    Microsoft Academic Search

    Ricardo Vasquez Padilla; Gökmen Demirkaya; D. Yogi Goswami; Elias Stefanakos; Muhammad M. Rahman

    2010-01-01

    Development of innovative thermodynamic cycles is important for the efficient utilization of low-temperature heat sources such as solar, geothermal and waste heat sources. This paper presents a parametric analysis of a combined power\\/cooling cycle, which combines the Rankine and absorption refrigeration cycles, uses ammonia-water mixture as the working fluid and produces power and cooling simultaneously. This cycle, also known as

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

    NASA Astrophysics Data System (ADS)

    Sigillito, A. J.; Malissa, H.; Tyryshkin, A. M.; Riemann, H.; Abrosimov, N. V.; Becker, P.; Pohl, H.-J.; Thewalt, M. L. W.; Itoh, K. M.; Morton, J. J. L.; Houck, A. A.; Schuster, D. I.; Lyon, S. A.

    2014-06-01

    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 (B1) 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 107 spins or 3×104spins/?Hz with averaging.

  16. A Unique Approach to Power Electronics and Motor Cooling in a Hybrid Electric Vehicle Environment

    SciTech Connect

    Ayers, Curtis William [ORNL; Hsu, John S [ORNL; Lowe, Kirk T [ORNL; Conklin, Jim [ORNL

    2007-01-01

    An innovative system for cooling the power electronics of hybrid electric vehicles is presented. This system uses a typical automotive refrigerant R-134a (1,1,1,2 tetrafluoroethane) as the cooling fluid in a system that can be used as either part of the existing vehicle passenger air conditioning system or separately and independently of the existing air conditioner. Because of the design characteristics, the cooling coefficient of performance is on the order of 40. Because liquid refrigerant is used to cool the electronics directly, high heat fluxes can result while maintaining an electronics junction temperature at an acceptable value. In addition, an inverter housing that occupies only half the volume of a conventional inverter has been designed to take advantage of this cooling system. Planned improvements should result in further volume reductions while maintaining a high power level.

  17. Rate of cooling and power consumption of farm milk coolers

    E-print Network

    McCardle, Arthur, Jr

    1952-01-01

    VIE Discussion of Resolta , , ~ . ~ . . . 51 VII. Corclusions ~ ~ ~ 55 VIII. sitsrsture Citsrl 55 Page X Typical data sheet for rats of cooling milk usinw agitated water bath with ice bank morning load~ Iarch 80, 195Ri The ambient temperature... was o Bla8 Pe ~ ~ ~ ~ ~ i ~ i ~ ~ I s o ~ ~ XI Typical data sheet for rate of cooling milk usins agitated water bath with ice bank - night load, Marsh 80, 19. ":R. Thc ambler t tcm-, erature waa 61. 6 P. III Typical -Tata sheet fer rate of cccliup...

  18. Advanced superconducting MHD magnet design for a retrofit power plant

    SciTech Connect

    Marston, P.G.; Hale, J.R.; Dawson, A.M.

    1989-03-01

    A magnet system has been designed for an MHD topping cycle retrofit of a conventional power plant. The channel power output wil be --35 MWe. The 4.5 T peak on-axis field magnet will be constructed of an unusual NbTi superconductor wound into four subunits per dipole half. These will be three 45/sup 0/ saddle coils with circular or ellipsoidal end turns and a single planar coil with a modified racetrack shape that will serve principally as a field shaping coil. This planar coil also enables a substantial reduction in the ratio of peak to central field strength. Among the unique features of this design will be the use of flexible bands in tension as the primary element of the transverse force containment structure. The conductor will be of the cable-in-conduit type with a low copper-to-superconductor ratio cable and a thick-walled aluminum conduit sheath. The sheath will support the axial loads on the saddles and will also provide thermal mass for protection against overheating in the event of an energy dump. The analysis and design of this magnet system and its projected advantages in both performance and economics are discussed.

  19. A High Power, Radiation Cooled, Rotating Toroidal Target

    E-print Network

    McDonald, Kirk

    IN A VACUUM VACUUM CHAMBER WALLS WATER COOLED #12;Slide 5 proton beam rotating ring, velocity v Schematic = the effective length of the target in the beam at any one time (20 cm) = the thermal emissivity (0.3) = Stefan ( )44 2 eTTgrl dt dq -= Stefan's Radiation Law Thermal Capacity ( )oTTSlrQ -= 2 L V QW = which gives

  20. Calculation and visual displaying of the water chemistry conditions in return cooling systems at thermal power stations

    NASA Astrophysics Data System (ADS)

    Ochkov, V. F.; Orlov, K. A.; Ivanov, E. N.; Makushin, A. A.

    2013-07-01

    Matters concerned with treatment of cooling water at thermal power stations are addressed. Problems arising during operation of return cooling systems equipped with cooling towers are analyzed. The software used for monitoring, control, and indication of the hydraulic and water chemistry operating conditions of the circulation system at the Yaivinsk district power station is considered.

  1. Implementation of superconducting fault current limiter for flexible operation in the power substation

    NASA Astrophysics Data System (ADS)

    Song, Chong Suk; Lee, Hansang; Cho, Yoon-sung; Suh, Jaewan; Jang, Gilsoo

    2014-09-01

    The concentration of large-scale power loads located in the metropolitan areas have resulted in high fault current levels during a fault thereby requiring the substation to operate in the double busbar configuration mode. However, the double busbar configuration mode results in deterioration of power system reliability and unbalanced power flow in the adjacent transmission lines which may result in issues such as overloading of lines. This paper proposes the implementation of the superconducting fault current limiter (SFCL) to be installed between the two substation busbars for a more efficient and flexible operation of the substation enabling both single and double busbar configurations depending on the system conditions for guaranteeing power system reliability as well as fault current limitations. Case studies are being performed for the effectiveness of the SFCL installation and results are compared for the cases where the substation is operating in single and double busbar mode and with and without the installation of the SFCL for fault current mitigation.

  2. Microscale Thermoelectric Cooling Elements (TECs) are being proposed to cool down an integrated circuit to maintain its performance. The maximum cooling power of microscale TECs is significantly reduced by the interfacial resistance. For our

    E-print Network

    ICT 2008 1 Abstract Microscale Thermoelectric Cooling Elements (TECs) are being proposed to cool act as a good guideline for two-dimensional analysis and assembly of TECs. Key Words - Thermoelectric by the thermal power at the hotspot regions. Microscale Thermoelectric Cooling Elements (TECs) or Thermoelectric

  3. Energy and peak power saved by passively cooled residences

    NASA Astrophysics Data System (ADS)

    Clark, G.; Loxsom, F.; Doderer, E.; Vieira, R.; Fleischhacker, P.

    1983-11-01

    The energy displacement potential of roof pond cooling in humid climates is sensitive to the type of dehumidification equipment employed and the humidity levels allowed. The simulated energy requirements of roof pond residences assisted by two high efficiency dehumidifier options are described. One dehumidifier was a vapor compression air conditioner with sensible cooling recovery by an air-to-air heat exchanger (improved mechanical dehumidification or IMD). The second option was a solar regenerated desiccant dehumidifier (SRDD). An IMD assisted roof pond house had energy savings of 30 to 65% in humid climates compared to the conventional house; an SRDD assisted roof pond house had energy savings of 70 to 75% in humid climates.

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

    SciTech Connect

    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

    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

  5. Method and system for powering and cooling semiconductor lasers

    DOEpatents

    Telford, Steven J; Ladran, Anthony S

    2014-02-25

    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.

  6. Utilization of municipal wastewater for cooling in thermoelectric power plants

    SciTech Connect

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

    2013-09-01

    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).

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

    SciTech Connect

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

    1999-04-01

    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.

  8. Thermoelectric power generator design and selection from TE cooling module specifications

    Microsoft Academic Search

    Richard J. Buist; Paul G. Lau

    1997-01-01

    There are many applications where thermoelectric (TE) coolers can be used effectively as power generators. In fact, where temperatures are less than 500 K, TE cooling modules are the best choice for power generation, whether it be from a cost or performance standpoint. The literature available on this subject is scarce and very limited in scope. This paper describes the

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

    Microsoft Academic Search

    Zaki Su'ud; Bakrie Arbie; Sedyartomo S

    2005-01-01

    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

  10. RF power upgrade at the superconducting 1.3 GHz CW LINAC "ELBE" with solid state amplifiers

    NASA Astrophysics Data System (ADS)

    Büttig, Hartmut; Arnold, A.; Büchner, A.; Justus, M.; Kuntsch, M.; Lehnert, U.; Michel, P.; Schurig, R.; Staats, G.; Teichert, J.

    2013-03-01

    The RF power for the superconducting 1.3 GHz CW LINAC "ELBE" has been doubled from less than 10 kW to 20 kW per cavity. In January 2012 the four 10 kW klystrons used to drive the four superconducting cavities of the LINAC have been replaced by pairs of 10 kW solid state power amplifiers (SSPA). ELBE is now worldwide the first 1.3 GHz CW LINAC equipped with solid state RF power amplifiers. This technical note details on this project.

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

    SciTech Connect

    Gary Vine

    2010-12-01

    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.

  12. Conceptual design study of the moderate size superconducting spherical tokamak power plant

    NASA Astrophysics Data System (ADS)

    Gi, Keii; Ono, Yasushi; Nakamura, Makoto; Someya, Youji; Utoh, Hiroyasu; Tobita, Kenji; Ono, Masayuki

    2015-06-01

    A new conceptual design of the superconducting spherical tokamak (ST) power plant was proposed as an attractive choice for tokamak fusion reactors. We reassessed a possibility of the ST as a power plant using the conservative reactor engineering constraints often used for the conventional tokamak reactor design. An extensive parameters scan which covers all ranges of feasible superconducting ST reactors was completed, and five constraints which include already achieved plasma magnetohydrodynamic (MHD) and confinement parameters in ST experiments were established for the purpose of choosing the optimum operation point. Based on comparison with the estimated future energy costs of electricity (COEs) in Japan, cost-effective ST reactors can be designed if their COEs are smaller than 120 mills kW?1 h?1 (2013). We selected the optimized design point: A = 2.0 and Rp = 5.4 m after considering the maintenance scheme and TF ripple. A self-consistent free-boundary MHD equilibrium and poloidal field coil configuration of the ST reactor were designed by modifying the neutral beam injection system and plasma profiles. The MHD stability of the equilibrium was analysed and a ramp-up scenario was considered for ensuring the new ST design. The optimized moderate-size ST power plant conceptual design realizes realistic plasma and fusion engineering parameters keeping its economic competitiveness against existing energy sources in Japan.

  13. Power system analysis of Hanlim superconducting HVDC system using real time digital simulator

    NASA Astrophysics Data System (ADS)

    Won, Y. J.; Kim, J. G.; Kim, A. R.; Kim, G. H.; Park, M.; Yu, I. K.; Sim, K. D.; Cho, J.; Lee, S.; Jeong, K. W.; Watanabe, K.

    2011-11-01

    Jeju island is located approximately 100 km south from the mainland of Korea, and had a peak load of about 553 MW in 2008. The demand increases 7.2% a year over the last 5 years. Since the wind profiles of Jeju island are more favorable than mainland of Korea, many companies have shown interest in the wind power business at the Jeju island. Moreover KEPCO has a plan for renewable energy test too whose power will be delivered by HVDC system. One kilometer length of total 8 km was designed as superconducting DC cable. Rest 7 km will be the conventional overhead line. In this paper, the authors have developed a simulation model of the power network around 8 km HVDC system using real time digital simulator (RTDS).

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

    PubMed

    Stillwell, Ashlynn S; Webber, Michael E

    2014-04-15

    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

  15. Advanced superconducting power conditioning system with SMES for effective use of renewable energy

    NASA Astrophysics Data System (ADS)

    Hamajima, T.; Tsuda, M.; Miyagi, D.; Amata, H.; Iwasaki, T.; Son, K.; Atomura, N.; Shintomi, T.; Makida, Y.; Takao, T.; Munakata, K.; Kajiwara, M.

    Since it is an urgent issue to reduce the global Carbon-dioxide in the world, renewable energy should be supplied as a large amount of the electric power. However, if a large amount of fluctuating renewable energy becomes more than adjustable amount of a utility grid capacity, instabilities such as frequency deviation might occur. We propose a system that is composed of SMES and FC-H2-Electrolyzer and also installed adjacent to Liquid Hydrogen station to cool down the SMES. Since the SMES has potentials of quick response and large I/O power, and Fuel Cell has potentials of slow response and steady power supplied from a large amount of hydrogen, we combine both storage devices and apply them to suppress the fluctuating power. We convert the fluctuating power to the constant power by using a developed prediction technology of Kalman filter to predict a trend of the fluctuating power. While the trend power should be supplied by FC or absorbed by the electrolyzer to produce hydrogen, the power difference between the renewable power and the trend power should be stored by the SMES. We simulate the power balance and analyze the required SMES capacity, design the concept of the SMES, and propose an operation algorithm for the SMES to estimate the electric efficiency of the system. It is found that the electric efficiency of the ASPCS can become greater than that of a pumped hydro-machine.

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

    SciTech Connect

    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

    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.

  17. 78 FR 64029 - Cost-Benefit Analysis for Radwaste Systems for Light-Water-Cooled Nuclear Power Reactors

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-25

    ...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....

  18. 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

    Nimmo, Francis

    water bill, water costs around 0.1 cents per gallon (or 103 times the cost of bottled water!). But we1. Cooling water is one-third of US water usage Basic approach: (a) estimate power consumption, from which you estimate cooling water usage and compare with (b) estimate of other water usage. (a

  19. Biocide usage in cooling towers in the electric power and petroleum refining industries

    SciTech Connect

    Veil, J.; Rice, J.K.; Raivel, M.E.S.

    1997-11-01

    Cooling towers users frequently apply biocides to the circulating cooling water to control growth of microorganisms, algae, and macroorganisms. Because of the toxic properties of biocides, there is a potential for the regulatory controls on their use and discharge to become increasingly more stringent. This report examines the types of biocides used in cooling towers by companies in the electric power and petroleum refining industries, and the experiences those companies have had in dealing with agencies that regulate cooling tower blowdown discharges. Results from a sample of 67 electric power plants indicate that the use of oxidizing biocides (particularly chlorine) is favored. Quaternary ammonia salts (quats), a type of nonoxidizing biocide, are also used in many power plant cooling towers. The experience of dealing with regulators to obtain approval to discharge biocides differs significantly between the two industries. In the electric power industry, discharges of any new biocide typically must be approved in writing by the regulatory agency. The approval process for refineries is less formal. In most cases, the refinery must notify the regulatory agency that it is planning to use a new biocide, but the refinery does not need to get written approval before using it. The conclusion of the report is that few of the surveyed facilities are having any difficulty in using and discharging the biocides they want to use.

  20. COOLING SYSTEM FOR THE MERIT HIGH-POWER TARGET EXPERIMENT

    SciTech Connect

    Haug, F.; Pereira, H.; Silva, P.; Pezzetti, M.; Pavlov, O.; Pirotte, O.; Metselaar, J.; Efthymiopoulos, I.; Fabich, A.; Lettry, J. [CERN, CH-1211, Geneva, 23 (Switzerland); Kirk, H. G. [BNL, Upton, NY 11973 (United States); McDonald, K. T. [Princeton University, Princeton, NJ 08544 (United States); Titus, P. [NW22-225 MIT Plasma Science and Fusion Center, 185 Albany Street, Cambridge MA 02139 (United States); Bennett, J. R. J. [CCLRC, RAL, Chilton, OX11 0QX (United Kingdom)

    2010-04-09

    MERIT is a proof-of-principle experiment of a target station suitable as source for future muon colliders or neutrino factories. When installed at the CERN (European Organization for Nuclear Research) PS (Proton Synchrotron) complex fast-extracted high-intensity proton beams intercepted a free mercury jet inside a normal-conducting, pulsed 15-T capture solenoid magnet cooled with liquid nitrogen. Up to 25 MJ of Joule heat was dissipated in the magnet during a pulse. The fully automated, remotely controlled cryogenic system of novel design permitted the transfer of nitrogen by the sole means of differential pressures inside the vessels. This fast cycling system permitted several hundred tests in less than three weeks during the 2007 data taking campaign.

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

    SciTech Connect

    Mann, Ron; Chavez, Miguel, E.

    2012-06-27

    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.

  2. Compact fluid cooled power converter supporting multiple circuit boards

    DOEpatents

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

    2005-03-08

    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.

  3. Evaluation of Hybrid Air-Cooled Flash/Binary Power Cycle

    SciTech Connect

    Greg Mines

    2005-10-01

    Geothermal binary power plants reject a significant portion of the heat removed from the geothermal fluid. Because of the relatively low temperature of the heat source (geothermal fluid), the performance of these plants is quite sensitive to the sink temperature to which heat is rejected. This is particularly true of air-cooled binary plants. Recent efforts by the geothermal industry have examined the potential to evaporatively cool the air entering the air-cooled condensers during the hotter portions of a summer day. While the work has shown the benefit of this concept, air-cooled binary plants are typically located in regions that lack an adequate supply of clean water for use in this evaporative cooling. In the work presented, this water issue is addressed by pre-flashing the geothermal fluid to produce a clean condensate that can be utilized during the hotter portions of the year to evaporatively cool the air. This study examines both the impact of this pre-flash on the performance of the binary plant, and the increase in power output due to the ability to incorporate an evaporative component to the heat rejection process.

  4. Study and realization of a high power density electronics device cooling loop using a liquid metal coolant

    Microsoft Academic Search

    Mansour Tawk; Yvan Avenas; Afef Kedous-Lebouc; Mickael Petit

    2011-01-01

    Thermal management became the limiting factor in the development of high power electronic devices and new methods of cooling are required. Due to the low thermal conductivity of classical liquids (water, alcohols, dielectric fluids…), in many cases, the standard liquid cooling techniques cannot achieve the required cooling performances. Therefore the use of liquid gallium alloys whose thermal conductivity (approx. 28W\\/m\\/K)

  5. Design and construction of a high temperature superconducting power cable cryostat for use in railway system applications

    NASA Astrophysics Data System (ADS)

    Tomita, M.; Muralidhar, M.; Suzuki, K.; Fukumoto, Y.; Ishihara, A.; Akasaka, T.; Kobayashi, Y.

    2013-10-01

    The primary objective of the current effort was to design and test a cryostat using a prototype five-meter long high temperature Bi2Sr2Ca2Cu3Oy (Bi-2223) superconducting dc power cable for railway systems. To satisfy the safety regulations of the Govt of Japan a mill sheet covered by super-insulation was used inside the walls of the cryostat. The thicknesses of various walls in the cryostat were obtained from a numerical analysis. A non-destructive inspection was utilized to find leaks under vacuum or pressure. The cryostat target temperature range was around 50 K, which is well below liquid nitrogen temperature, the operating temperature of the superconducting cable. The qualification testing was carried out from 77 down to 66 K. When using only the inner sheet wire, the maximum current at 77.3 K was 10 kA. The critical current (Ic) value increased with decreasing temperature and reached 11.79 kA at 73.7 K. This is the largest dc current reported in a Bi2Sr2Ca2Cu3Oy or YBa2Cu3Oy (Y-123) superconducting prototype cable so far. These results verify that the developed DC superconducting cable is reliable and fulfils all the requirements necessary for successful use in various power applications including railway systems. The key issues for the design of a reliable cryogenic system for superconducting power cables for railway systems are discussed.

  6. A New Water-Cooled Power Vacuum Tube

    Microsoft Academic Search

    I. E. Mouromtseff

    1932-01-01

    Part I. The evolution of transmitting tubes is outlined. The ever present desirability of using a single tube for a given power output instead of paralleling several smaller tubes leads finally to the design and construction of tubes with 100-kw output, or larger. The design of a tube for 100- to 200-kw output is described. A basically new feature of

  7. High power density self-cooled lithium-vanadium blanket.

    SciTech Connect

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

    1999-07-01

    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.

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

    SciTech Connect

    Wagner, M. J.; Kutscher, C.

    2010-01-01

    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).

  9. Wind tunnel simulation on re-circulation of air-cooled condensers of a power plant

    Microsoft Academic Search

    Zhifu Gu; Hui Li; Wenhong Zhang; Yan Li; Jiye Peng

    2005-01-01

    The criteria as well as the methods and measurements of wind tunnel simulation on wind effects on air-cooled condensers in a power plant were discussed. The parameter of re-circulation was suggested to describe the wind effects on the efficiency of the condenser. The result of practical project models shows that great wind effects of both wind speed and the angle

  10. CoolSpots: reducing the power consumption of wireless mobile devices with multiple radio interfaces

    Microsoft Academic Search

    Trevor Pering; Yuvraj Agarwal; Rajesh K. Gupta; Roy Want

    2006-01-01

    CoolSpots enable a wireless mobile device to automatically switch between multiple radio interfaces, such as WiFi and Bluetooth, in order to increase battery lifetime. The main contribution of this work is an exploration of the policies that enable a system to switch among these interfaces, each with diverse radio characteristics and different ranges, in order to save power - supported

  11. Hydro energy potential of cooling water at the thermal power plant

    Microsoft Academic Search

    Vladimir D. Stevanovic; Aleksandar Gajic; Ljubodrag Savic; Vladan Kuzmanovic; Dusan Arnautovic; Tina Dasic; Blazenka Maslovaric; Sanja Prica; Bojan Milovanovic

    2011-01-01

    The hydro energy of the gravity water flow from the coal-fired thermal power plant units to the river in an open cooling system of turbine condensers is determined. On the basis of statistical data for a long time period, the water net head duration curve due to the river annual level change, as well as the reduction of the hydro

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

    Microsoft Academic Search

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

    1999-01-01

    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

  13. Enhancement of a two-phase thermosyphon for cooling high heat flux power devices

    Microsoft Academic Search

    Heikichi Kuwahara; Kenji Takahashi; Tadakatsu Nakajima; Toshio Takasaki; S. O. Suzuki

    1995-01-01

    The purpose of this study is the enhancement of cooling of high heat flux power devices such as a thyristor by a thermosyphon system. The thermosyphon uses boiling and condensation of an inert dielectric fluorocarbon (FC-72). Boiling occurs from a multiple chimney heat transfer structure. A boiling chamber is connected to the condenser by a double tube, with the inner

  14. Enhancement of two-phase thermosyphon for cooling high heat flux power devices

    Microsoft Academic Search

    Heikichi Kuwahara; Kenji Takahashi; Tadakatsu Nakajima; Osamu Suzuki; Toshio Takasaki

    1994-01-01

    The purpose of this study is the enhancement of cooling of high heat flux power devices such as a thyristor by a thermosyphon system. The thermosyphon used boiling and condensation of inert dielectric fluorocarbon (FC-72). Boiling occurred from a multiple chimney heat transfer structure. A boiling chamber is connected to the condenser by a double tube, with the inner tube

  15. Improvements in and relating to thermal power plant employing gas-cooled nuclear reactors

    Microsoft Academic Search

    A. B. Jackson; J. S. Pumphrey; G. R. Wood

    1973-01-01

    A power plant employing a gas cooled reactor is described, in which hot ; gas from the reactor is used in a closed cycle as the working fluid of a gas ; turbine plant. Gas exhausting from the turbine plant passes, prior to its return ; to the reactor, through a heat exchanger to cause vaporization of a separate ;

  16. BRENDA: a dynamic simulator for a sodium-cooled fast reactor power plant

    Microsoft Academic Search

    D. L. Hetrick; G. W. Sowers

    1978-01-01

    This report is a users' manual for one version of BRENDA (Breeder Reactor Nuclear Dynamic Analysis), which is a digital program for simulating the dynamic behavior of a sodium-cooled fast reactor power plant. This version, which contains 57 differential equations, represents a simplified model of the Clinch River Breeder Reactor Project (CRBRP). BRENDA is an input deck for DARE P

  17. NREL Helps Cool the Power Electronics in Electric Vehicles (Fact Sheet)

    SciTech Connect

    Not Available

    2011-07-01

    Researchers at the National Renewable Energy Laboratory (NREL) are developing and demonstrating innovative heat-transfer technologies for cooling power electronics devices in hybrid and electric vehicles. In collaboration with 3M and Wolverine Tube, Inc., NREL is using surface enhancements to dissipate heat more effectively, permitting a reduction in the size of power electronic systems and potentially reducing the overall costs of electric vehicles.

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

    Microsoft Academic Search

    Gershon Grossman

    2002-01-01

    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-

  19. Control of Superconducting Magnetic Energy Storage Units in Multi-Machine Power Systems

    NASA Astrophysics Data System (ADS)

    Ranaweera, Aruna

    A new scheme, in which a synchronous generator connected to the SMES busbar is used as a feedback generator, is proposed to control superconducting magnetic energy storage (SMES) units in multi-machine power systems, in this dissertation. The speed and the load angle changes of the feedback generator are used to calculate the necessary real power transfers to the SMES, while the necessary reactive power transfers are calculated from the voltage changes of the common busbar. Expressions are derived for the direct and quadrature axis components of the current drawn by the SMES, for unequal firing angles in the converter bridge, and the relationships of the two currents to the total real and reactive power transfers to the SMES are shown. The expressions derived are valid for small or large systems, under steady state or transient conditions, and it is shown through computer simulations in a small power system that, the proposed scheme is quite effective in stabilizing electromechanical oscillations caused by small as well as large disturbances. It is also shown that, the SMES can improve the power output of wind turbine induction generators, and also stabilize the oscillations caused by wind power losses in a steam turbine generator system, and thereby eliminate the need to use diesel turbine generators for the same purpose. Finally, equations are derived to represent the synchronous machine in terms of its d-q circuits, while it is connected to the network which is described by complex quantities, and the formulations done for the proposed scheme are extended to study the use of SMES units with proposed control in power systems of large and complex configurations. The proposed scheme of control is simple, and does not call for a special design of a controller requiring simplifying assumptions such as the presence of an infinite busbar or steady state operating conditions on the system, and therefore, would help in the widespread use of SMES units in electric utilities.

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

    SciTech Connect

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

    1997-05-01

    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.

  1. ORNL Superconducting Technology Program for electric power systems. Annual report for FY 1995

    SciTech Connect

    Hawsey, R.A. [comp.; Turner, J.W. [ed.

    1996-05-01

    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 systems 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 1995 Annual Program Review held August 1-2, 1995. 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. 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.

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

    SciTech Connect

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

    1998-03-01

    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.

  3. 10 CFR 50.46 - Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...cooling systems for light-water nuclear power reactors. 50.46 Section 50...systems for light-water nuclear power reactors. (a)(1)(i) Each... (2) The Director of Nuclear Reactor Regulation may impose...

  4. 10 CFR 50.46 - Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...cooling systems for light-water nuclear power reactors. 50.46 Section 50...systems for light-water nuclear power reactors. (a)(1)(i) Each... (2) The Director of Nuclear Reactor Regulation may impose...

  5. 10 CFR 50.46 - Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...cooling systems for light-water nuclear power reactors. 50.46 Section 50...systems for light-water nuclear power reactors. (a)(1)(i) Each... (2) The Director of Nuclear Reactor Regulation may impose...

  6. Development of a new 6. 6kV/1500A class superconducting fault current limiter for electric power systems

    SciTech Connect

    Hara, T.; Okuma, T.; Yamamoto, T. (Tokyo Electric Power Co. (Japan)); Ito, D.; Tasaki, K.; Tsurunaga, K. (Toshiba Corp., Tokyo (Japan))

    1993-01-01

    The present paper first proposes a new type of superconducting current limiter comprising a non-inductively wound AC superconducting coil (trigger coil) connected in parallel with a limiting coil. Furthermore, a model electric power system for the application of this type of superconducting current limiters was created, a 400V/100A class model superconducting current limiters was fabricated, and various current limiting tests were performed with respect to short-circuit currents and phases varied over a wide range. The results so obtained demonstrated that the present type of current limiter possessed performance characteristics fully adequate for application to the model system. Moreover, with a view to increased capacity, a 6.6kV/1500A class superconducting trigger coil was developed with a scale permitting, in principle, validation tests of applicability to actual power systems. This coil was demonstrated to be capable of limiting short-circuit currents by a factor of 1/30, and was subjected to detailed evaluation of current limiting characteristics.

  7. Superconductive electronics-a high speed and low power technology complementing III-V technologies for advanced systems

    Microsoft Academic Search

    Michael Leung; John Spargo; Kevin Kobayashi; Amold Silver

    1997-01-01

    Superconductive electronics offers a unique combination of high bandwidth and low power for mission critical hardware such as digital processors at 20 to 100 GHz, microwatt per bit analog to digital converters, large digital switches at multi-Gb\\/s data rates, and low noise parametric amplifiers. This cryogenic technology, typically operating at a few degrees or a few tens of degrees Kelvin,

  8. AN ASSESSMENT METHOD FOR ENVIRONMENTAL IMPACTS OF THE RESIDUE CHLORINE IN THE COOLING WATER EFFLUENT OF THERMAL (NUCLEAR) POWER PLANTS

    Microsoft Academic Search

    Hongwu TAN; Lanfen LIU

    For the vast cooling water flow of thermal (nuclear) power plants and the large amount of the Chlorine adding to prevent biofouling in the cooling water systems, the residue Chlorine is a severe threat to the water environment. How to properly estimate the impacting range and extent is an outstanding problem in the EIA field of thermal power plants. Based

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

    NASA Technical Reports Server (NTRS)

    Schwarze, G. E.

    1985-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Schwarze, G. E.

    1985-01-01

    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 the 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.

  11. Application of evaporative cooling technology in super-high power density magnet.

    PubMed

    Xiong, B; Ruan, L; Gu, G B; Guo, S Q; Cao, R; Li, Z G; Lu, W; Zhang, X Z; Sun, L T; Zhao, H W

    2014-02-01

    Evaporative cooling technology utilizes phase-change heat transfer mode to achieve the cooling for heating equipment. The heat transfer capacity of evaporative cooling technology is far more than air or water cooling technology. The Electron Cyclotron Resonance ion source magnet is a typical super-high power density magnet, and the evaporative cooling technology is an ideal cooling method for the coils of magnet. In this paper we show the structure and process of coils and the special design of flow channels of coolant for an experiment magnet model. Additionally, the heat transfer circulation is presented and analyzed. By the finite element method, the flow channels are optimized to rationally allocate coolant and to reduce the temperature of coils. For the experiment model, the current density of copper wire of coils is 19 A/mm(2), and the coil-windows current density is larger than 12 A/mm(2). The max temperature of coils is below 80?°C, and the total heat is about 200 kW. PMID:24593492

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

    SciTech Connect

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

    1984-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

    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.

  14. Superconducting alternating current cable

    Microsoft Academic Search

    Kafka

    1971-01-01

    A superconducting alternating current cable has a space for conducting a fluid of insulating helium and a carrier member for conducting a fluid of cooling helium. The carrier member maintains the insulating helium separate from the cooling helium, the insulating helium being kept at a pressure different from that of the cooling helium.

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

    SciTech Connect

    C. McGowin; M. DiFilippo; L. Weintraub

    2006-06-30

    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.

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

    PubMed

    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

    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

  17. Performances of Stirling Type Pulse Tube Cryocooler for Sub-cooled Nitrogen System

    Microsoft Academic Search

    Y. Ohtani; T. Yazawa; T. Kuriyama; M. Urata; K. Inoue

    2006-01-01

    This paper describes performances of a Stirling type pulse tube cryocooler as a nitrogen sub-cooler. The main objective of this work is a demonstration of a cooling system for High Tc Superconducting (HTS) power applications such as fault current limiters, cables and transformers. Cooling capacity necessary for these applications is more than several hundred watts at 77 K level. High

  18. Microchannel cooling of traveling-wave-tube circuit for ultrawideband high-power submillimeter-wave generation

    Microsoft Academic Search

    Yanbao Ma; Avijit Bhunia; Mark Field; Chung-Lung Chen

    2010-01-01

    High heat dissipation is generated in Traveling-wave-tube circuit for ultrawideband high-power submillimeter-wave generation due to e-beam power loss during transport. Active cooling is required to ensure the device can physically handle the high heat flux without damage. An efficient thermal management solution is provided for cooling the high-power vacuum device based on microchannel technology. A thermal conduction model is developed

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

    SciTech Connect

    Li, Jianjian; /IIT, Chicago

    2008-12-01

    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.

  20. High Power RF Processing Studies of 3 GHZ Niobium Superconducting Accelerator Cavities

    NASA Astrophysics Data System (ADS)

    Graber, Joel Henry

    Superconducting radio-frequency (SRF) cavities are a promising technology for future high energy particle accelerators. SRF technology is presently limited by field emission (FE), a quantum mechanical tunneling effect wherein electrons are emitted from a metal surface into vacuum in the presence of a strong electric field. A systematic study is presented of the effects of pulsed high power RF processing (HPP) as a method of understanding and reducing field emission in SRF cavities. The HPP experimental apparatus was built to provide up to 200 kW peak RF power to 3 GHz cavities, for pulse lengths of hundreds of microseconds. Single-cell, two-cell, and nine -cell cavities were tested extensively. HPP proved to be a highly successful method of reducing FE loading in SRF cavities. Attainable continuous wave (CW) fields are increased by as much as 80% from their pre-HPP limits. Analysis of HPP results and data increases our understanding of the nature of RF processing. Clear correlations are obtained linking FE reduction with the maximum electric field attained during processing. Analysis of the pulsed behavior of the cavities indicates that thermal breakdown, initiated by high surface magnetic fields, is a dominant limitation on the attainable fields. A thermal model is developed which accurately predicts the limitations. A special two-cell cavity with a reduced magnetic to electric field ratio is successfully tested. During HPP, pulsed fields reach E_{peak} = 113 MV/m (H_{peak} = 1600 Oe), and subsequent low power measurement reaches E_{peak} = 100 MV/m ( H_{peak} = 1420 Oe), the highest CW field ever measured in a superconducting accelerator cavity. Additional studies improve our understanding of the microscopic effect of HPP. Thermometry measurements of the outer wall of single-cell cavities reveal that processing gains are made by reduction in emission from localized sites. Scanning electron microscope examination of RF surfaces reveals craters and other phenomena which indicate that processing occurs through a violent melting/vaporization phenomenon. A "model" for RF processing is presented based upon the experimental evidence, both from this study and from other related experiments.

  1. On the development of an ion-beam stochastic cooling system for the nuclotron superconducting accelerator complex

    NASA Astrophysics Data System (ADS)

    Kobets, A. G.; Sidorin, A. O.; Trubnikov, G. V.; Shurkhno, N. A.

    2012-07-01

    The Joint Institute for Nuclear Research (JINR) initiated the creation of a unique heavy-ion collider, the Nuclotron-based ion collider facility (NICA), which is planned to be put into commission in 2016. According to the calculation data, the collider luminosity, which should be kept at a record high level of 1027 cm-2 s-1, will gradually decrease, mainly due to intrabeam scattering. To maintain luminosity at a high level, it is necessary to include a cooling system in the base project of the accelerator. Among the two cooling methods (electron and stochastic) most frequently used for heavy ion beams, stochastic cooling seems more attractive. However, there has been a lack of experience in the development and commissioning of such systems in Russia. For this reason, an experiment on stochastic cooling on the Nuclotron accelerator is being prepared to explore the technology and possibilities of this method. In this work, the method of stochastic cooling, the technique for calculating the cooling dynamics, and the experimental setup under development are briefly described.

  2. Survey of Remote Area Monitoring Systems at U.S. Light-Water-Cooled Power Reactors

    SciTech Connect

    Kathren, R. L.; Mileham, A. P.

    1982-04-01

    A study was made of the capabilities and operating practices, including calibration, of remote area monitoring (RAM) systems at light-water-cooled power reactors in the United States. The information was obtained by mail questionaire. Specific design capabilities, including range, readout and alarm features are documented along with the numbers and location of detectors, calibration and operational procedures. Comments of respondents regarding RAM systems are also included.

  3. Cooling performance of silicon-based thermoelectric device on high power LED

    Microsoft Academic Search

    Jen-Hau Cheng; Chun-Kai Liu; Yu-Lin Chao; Ra-Min Tain

    2005-01-01

    In this paper, a new thermal management application of silicon-based thermoelectric (TE) device on high power LED is unveiled. The silicon-based TE device is fabricated by the microfabrication and flip-chip assembly process. Thermal images photographed by infrared camera demonstrate the cooling function of the silicon-based TE devices. Because the LED chip is encapsulated in a package, the junction temperature of

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

    E-print Network

    Toshiyuki Hosoya; Martin Miranda; Ryotaro Inoue; Mikio Kozuma

    2014-12-02

    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.

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

    SciTech Connect

    Monado, Fiber [Nuclear Physics and Biophysics Research Group, Dept. of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Bandung, Indonesia and Dept. of Physics, Faculty of Mathematics and Natural Sciences, Sriwijaya University (Indonesia); Su'ud, Zaki; Waris, Abdul; Basar, Khairul [Nuclear Physics and Biophysics Research Group, Dept. of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Bandung (Indonesia); Ariani, Menik [Dept. of Physics, Faculty of Mathematics and Natural Sciences, Sriwijaya University (Indonesia); Sekimoto, Hiroshi [CRINES, Tokyo Institute of Technology, O-okoyama, Meguro-ku, Tokyo 152-8550 (Japan)

    2014-09-30

    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.

  6. Solar-powered cooling systems: Technical and economic analysis on industrial refrigeration and air-conditioning applications

    Microsoft Academic Search

    Umberto Desideri; Stefania Proietti; Paolo Sdringola

    2009-01-01

    In the last years, the growing demand for air conditioning has caused a significant increase in demand for primary energy resources. Solar-powered cooling is one of the technologies which allows to obtain, by using the renewable solar source, an important energy saving compared to traditional air conditioning plants. The paper describes different technical installations for solar cooling, their way of

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

    SciTech Connect

    Charles Reece, Hui Tian, Michael Kelley, Chen Xu

    2012-04-01

    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.

  8. Fast granular superconducting bolometer

    SciTech Connect

    Wolf, S.A.; Strom, U.; Weiser, K.

    1984-08-07

    A granular superconducting thin film bolometer made by anodizing a thin film of such materials as niobium nitride to form a thin granular film separated by and covered with the anodized oxide. The bolometer is cooled to its superconducting state and electrically connected to a biasing and detecting network. Its temporal response is better than 1 ns.

  9. Performance of first high temperature superconducting ECRIS

    SciTech Connect

    Kanjilal, D.; Rodrigues, G.; Kumar, P.; Mandal, A.; Roy, A.; Bieth, C.; Kantas, S.; Sortais, P. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi, 110067 India (India); Pantechnik, 12 rue Alfred Kastler, 14000 Caen (France); Laboratoire de Physique Subatomique et de Cosmologie, 53 avenue des Martyrs, 38026 Grenoble Cedex (France)

    2006-03-15

    High temperature superconducting (HTS) electron cyclotron resonance ion source called PKDELIS was designed, developed as a collaborative project mainly between Inter University Accelerator Centre (formerly Nuclear Science Centre) and Pantechnik. One of the major criteria of the design was to get a high performance source suitable for cryogen-free operation on a high voltage platform with minimum requirements of electrical power and cooling water. Ion beams having A/q of {approx}7 are required from this source for the high current injector of the superconducting linear accelerator. The HTS coils have been operational since 2003. A 80 mm gap, medium resolution, 'third order' corrected analyzing magnet having a bending radius of 300 mm has been coupled close to the source. The analyzed beam is collected using a high power, water cooled Faraday cup. The design and performance of the source and issues related to the extraction and transport of the beam are discussed in detail.

  10. Electromagnetic and thermal analysis of distributed cooled high power millimeter wave windows

    NASA Astrophysics Data System (ADS)

    Nelson, Scott D.; Reitter, Thomas; Caplan, Malcolm; Moeller, Charles

    1996-02-01

    The sectional high-frequency internally-cooled window, as proposed by General Atomics(1), has unique potential for allowing microwave sources to reach multi-megawatt CW levels with application to ECRH. Designs are being investigated using computational electromagnetic (EM), thermal, and mechanical codes at 110 GHz and 170 GHz to examine the design tradeoffs between RF performance and thermal mechanical safety margins. The EM analyses are for the window, under vacuum at one MW and includes variations in the shapes of the cooling fins, the surface treatment of the window elements themselves, the cooling fin tip treatment, the window pitch angle, and the waveguide effects. One advantage of the distributed cooled window is it's extensibility to higher power levels. Results in the modeling efforts are presented showing the EM field concentrations (which then will feed into the thermal analysis), the energy scattering/reflection, the transmitted launch angle variation as a function of physical geometry, and the spatial energy distribution and loss as a function of time and position.

  11. Electromagnetic and thermal analysis of distributed cooled high power millimeter wave windows

    NASA Astrophysics Data System (ADS)

    Nelson, S. D.; Reitter, T.; Caplan, M.

    1995-05-01

    The sectional high-frequency internally-cooled window, as proposed by General Atomics, has unique potential for allowing microwave sources to reach multi-megawatt CW levels with application to ECRH. Designs are being investigated using computational electromagnetic (EM), thermal, and mechanical codes at 110 GHz and 170 GHz to examine the design tradeoffs between RF performance and thermal mechanical safety margins. The EM analyses are for the window, under vacuum at one MW and includes variations in the shapes of the cooling fins, the surface treatment of the window elements themselves, the cooling fin tip treatment, the window pitch angle, and the waveguide effects. One advantage of the distributed cooled window is it's extensibility to higher power levels. Results in the modeling efforts are presented showing the EM field concentrations (which then will feed into the thermal analysis), the energy scattering/reflection, the transmitted launch angle variation as a function of physical geometry, and the spatial energy distribution and loss as a function of time and position.

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

    PubMed

    Klein, Sharon J W

    2013-12-17

    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

  13. Conceptual system design of a 5 MWh\\/100 MW superconducting flywheel energy storage plant for power utility applications

    Microsoft Academic Search

    H. J. Bornemann; M. Sander

    1997-01-01

    The authors have designed a 5 MWh\\/100 MW superconducting flywheel energy storage plant. The plant consists of 10 flywheel modules rated at 0.5 MWh\\/10 MW each. Module weight is 30 t, size is ? 3.5 m×6.5 m high. A synchronous type motor-generator is used for power input\\/output. Each flywheel system consists of four disk modules made from a carbon fibre

  14. Analysis of a new thermodynamic cycle for combined power and cooling using low and mid temperature solar collectors

    Microsoft Academic Search

    D. Yogi Goswami; Feng Xu

    1999-01-01

    A combined thermal power and cooling cycle is proposed which combines the Rankine and absorption refrigeration cycles. It can provide power output as well as refrigeration with power generation as a primary goal. Ammonia-water mixture is used as a working fluid. The boiling temperature of the ammonia-water mixture increases as the boiling process proceeds until all liquid is vaporized, so

  15. Use of caged fish for mariculture and environmental monitoring in a power-plant cooling-water system

    E-print Network

    Chamberlain, George William

    1978-01-01

    attempted to cage- culture inshore and estuarine species in thermal effluent. Smith (1973) reared Florida pampas (Trachinotus carolinus) in cages. within the cooling system of a power plant in Miami, Florida. This thermophilic species grew year...

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

    SciTech Connect

    Trage, B. (Blacke-Durr AG, Ratingen (DE)); Ham, A.J. (ESKOM, Johannesburg (ZA)); Vicary, T.C. (Zurn Balcke-Durr, Inc., Tampa, FL (US))

    1990-01-01

    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, and which have a power generation capacity of over 100 MWe are listed. It is evident from this that there is a predominance of indirect cooling systems. Although the actual investment costs for the direct system are lower, the reasons for selecting an indirect system for Kendal power station was essentially for conservative reasons. A long term comparison of the two different systems is made considering all influences including weather, long term durability, and availability. The two systems have seldom before been assessed correctly from an economic stand point.

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

    SciTech Connect

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

    2011-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2012-09-01

    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.

  19. Palm-size miniature superconducting bulk magnet

    NASA Astrophysics Data System (ADS)

    Saho, Norihide; Matsuda, Kazuya; Nishijima, Noriyo

    The development of a small, light, powerful and energy-efficient superconducting magnet has been desired in order to realize better efficiency and manipulability in guiding magnetic nano-particles, magnetic organic cells and other items to the right place. This study focuses on the development of a high-temperature superconducting (HTS) bulk magnet characterized by comparatively low leak magnetism despite a relatively high magnetic field. On this basis, the authors developed a palm-sized superconducting bulk magnet, which is the world's smallest, lightest, and lowest power consuming, as well as a new technology to effectively magnetize such a bulk magnet in a compact Stirling-cycle cryocooler (magnet C) with a pre-magnetized HTS bulk magnet (magnet B) in a compact cryocooler. This technology is demonstrated in two steps. In the first step, magnet B is magnetized using a superconducting solenoid magnet with a high magnetic field (magnet A) via the field cooling method. In the second step, magnet C is magnetized in the high magnetic field of magnet B. The prototype magnet C weighs 1.8 kg, and measures 235 × 65 × 115 mm (L × W × H). Magnet B was magnetized to 4.9 T using a 5 T magnet, and the target, magnet C, was magnetized using magnet B so that its maximum trapped magnetic flux density reached the value of 3.15 T. The net power consumption in a steady cooling state was 23 W, which is very low and comparable to that of a laptop computer.

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

    SciTech Connect

    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

    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)

  1. European development of He-cooled divertors for fusion power plants

    NASA Astrophysics Data System (ADS)

    Norajitra, P.; Giniyatulin, R.; Ihli, T.; Janeschitz, G.; Karditsas, P.; Krauss, W.; Kruessmann, R.; Kuznetsov, V.; Maisonnier, D.; Mazul, I.; Nardi, C.; Ovchinnikov, I.; Papastergiou, S.; Pizzuto, A.; Sardain, P.

    2005-11-01

    Helium-cooled divertor concepts are considered suitable for use in fusion power plants for safety reasons, as they enable the use of a coolant compatible with any blanket concept, since water would not be acceptable, e.g. in connection with ceramic breeder blankets using large amounts of beryllium. Moreover, they allow for a high coolant exit temperature for increasing the efficiency of the power conversion system. Within the framework of the European power plant conceptual study, different helium-cooled divertor concepts based on different heat transfer mechanisms are being investigated at ENEA Frascati, Italy, and Forschungszentrum Karlsruhe, Germany. They are based on a modular design which helps reduce thermal stresses. The design goal is to withstand a high heat flux of about 10-15 MW m-2, a value which is considered relevant to future fusion power plants to be built after ITER. The development and optimization of the divertor concepts require an iterative design approach with analyses, studies of materials and fabrication technologies and the execution of experiments. These issues and the state of the art of divertor development shall be the subject of this report.

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

    NASA Astrophysics Data System (ADS)

    Bell, Lon E.

    2008-09-01

    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.

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

    PubMed

    Bell, Lon E

    2008-09-12

    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

  4. Large Relative Cooling Power in Dy5Si4:Dy5Si3 composite

    NASA Astrophysics Data System (ADS)

    Samatham, S. Shanmukharao; Venkateshwarlu, D.; Pandya, Swati; Gangrade, Mohan; Chandra, L. S. Sharath; Jain, Deepti; Ganesan, V.

    2011-07-01

    Anomalously large RCP (Relative Cooling Power) and a reasonable high adiabatic change `?T' has been observed in magnetocaloric composite sample Dy5Si4 : Dy5Si3 for a nominal ratio of 2:1. Observed magnetic ordering temperatures for such a composite is 136 K and 39 K respectively which can be assigned to its constituents. Even though the observed `?T' is only 5 K for a field of 14 T, the combined RCP is very large, viz 1283 J/kg. Added merit is the width of temperature over which cooling can be done is 95 K. This makes the system more promising and may be a possible candidate for the Ericsson cycle over a temperature range from 140-35 K.

  5. Liquid-cooled ceramic Nd:YAG split-disk amplifier for high-average-power laser

    NASA Astrophysics Data System (ADS)

    Okada, Hajime; Yoshida, Hidetsugu; Fujita, Hisanori; Nakatsuka, Masahiro

    2006-10-01

    A liquid-cooled ceramic Nd:YAG split-disk laser amplifier has been designed for a high-average-power laser system. The maximum average output power of 17.1 W (1.71 J at 10 Hz) and the beam size of far-field pattern with 1.5 times diffraction limit was obtained. The combination of liquid cooling for disk laser material and wavefront compensation with a phase conjugation mirror was demonstrated. The wavefront degradation by liquid cooling was observed and measured with Michelson interferometer and far-field patterns.

  6. Superconducting mirror for laser gyroscope

    SciTech Connect

    Wang, X.

    1991-05-14

    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.

  7. Development of a 1 T cryocooler-cooled pulse coil with a Bi2223 superconducting parallel conductor for SMES

    Microsoft Academic Search

    M. Iwakuma; K. Funaki; K. Kajikawa; H. Kanetaka; H. Hayashi; K. Tsutsumi; A. Tomioka; M. Konno; S. Nose

    1999-01-01

    The authors designed and fabricated a 1 T cryocooler-cooled pulse coil operating at 40 K. A 4-strand interlayer-transposed parallel conductor composed of Bi-2223 rectangular cross-sectional multifilamentary wires was adopted to realize a uniform current distribution and to reduce the AC loss density down to the level of that of a single strand. The pulse coil is a 16-layer solenoidal one

  8. Characterization of the Performance of a Quasi-Optical NbN Superconducting HEB Mixer

    Microsoft Academic Search

    L. Jiang; W. Zhang; N. Li; Z. H. Lin; Q. J. Yao; W. Miao; S. C. Shi; S. I. Svechnikov; Y. B. Vakhtomin; S. V. Antipov; B. M. Voronov; G. N. Goltsman

    2007-01-01

    In this paper we focus mainly on the investigation of the performance of a quasi-optical (planar log-spiral antenna) phonon-cooled NbN superconducting hot electron bolometer (HEB) mixer, which is cryogenically cooled by a close-cycled 4-K cryocooler, at 500 and 850 GHz frequency bands. The mixer's noise performance, stability of IF output power, and local oscillator (LO) power requirement are characterized for

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

    NASA Astrophysics Data System (ADS)

    Li, Kenneth

    2014-02-01

    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.

  10. Presence of pathogenic amoebae in power plant cooling waters. Final report, October 15, 1977-September 30, 1979. [Naegleria fowleri

    SciTech Connect

    Tyndall, R.L.; Willaert, E.; Stevens, A.R.

    1981-03-01

    Cooling-water-associated algae and sediments from five northern and five southern or western electric power plants were tested for the presence of pathogenic amoebae. In addition, water algae and sediments from five northern and five southern/western sites not associated with power plants were tested. There was a significant correlation at northern power plants between the presence of thermophilic, pathogenic amoebae in cooling waters and thermal additions. Presence of the pathogenic did not correlate with salinity, pH, conductivity, or a variety of various chemical components of the cooling waters. Selected pathogenic isolates were tested serologically and were classified as Naegleria fowleri. Although thermal additions were shown to be contributing factor in predisposing cooling waters to the growth of pathogenic amoebae, the data suggest the involvement of other currently undefined parameters associated with the presence of the pathogenic amoebae. 35 refs., 21 tabs.

  11. Optimal Self-Tuning PID Controller Based on Low Power Consumption for a Server Fan Cooling System.

    PubMed

    Lee, Chengming; Chen, Rongshun

    2015-01-01

    Recently, saving the cooling power in servers by controlling the fan speed has attracted considerable attention because of the increasing demand for high-density servers. This paper presents an optimal self-tuning proportional-integral-derivative (PID) controller, combining a PID neural network (PIDNN) with fan-power-based optimization in the transient-state temperature response in the time domain, for a server fan cooling system. Because the thermal model of the cooling system is nonlinear and complex, a server mockup system simulating a 1U rack server was constructed and a fan power model was created using a third-order nonlinear curve fit to determine the cooling power consumption by the fan speed control. PIDNN with a time domain criterion is used to tune all online and optimized PID gains. The proposed controller was validated through experiments of step response when the server operated from the low to high power state. The results show that up to 14% of a server's fan cooling power can be saved if the fan control permits a slight temperature response overshoot in the electronic components, which may provide a time-saving strategy for tuning the PID controller to control the server fan speed during low fan power consumption. PMID:26007725

  12. Optimal Self-Tuning PID Controller Based on Low Power Consumption for a Server Fan Cooling System

    PubMed Central

    Lee, Chengming; Chen, Rongshun

    2015-01-01

    Recently, saving the cooling power in servers by controlling the fan speed has attracted considerable attention because of the increasing demand for high-density servers. This paper presents an optimal self-tuning proportional-integral-derivative (PID) controller, combining a PID neural network (PIDNN) with fan-power-based optimization in the transient-state temperature response in the time domain, for a server fan cooling system. Because the thermal model of the cooling system is nonlinear and complex, a server mockup system simulating a 1U rack server was constructed and a fan power model was created using a third-order nonlinear curve fit to determine the cooling power consumption by the fan speed control. PIDNN with a time domain criterion is used to tune all online and optimized PID gains. The proposed controller was validated through experiments of step response when the server operated from the low to high power state. The results show that up to 14% of a server’s fan cooling power can be saved if the fan control permits a slight temperature response overshoot in the electronic components, which may provide a time-saving strategy for tuning the PID controller to control the server fan speed during low fan power consumption. PMID:26007725

  13. Fe/Cr substitution in MnAs compound: Increase in the relative cooling power

    NASA Astrophysics Data System (ADS)

    Mejía, C. Salazar; Gomes, A. M.; Reis, M. S.; Rocco, D. L.

    2011-03-01

    We improved the magnetocaloric potential of MnAs compounds by stoichiometry decrease in Mn through small substitution by Fe and Cr. Isothermal magnetization measurements present hysteresis with metamagnetic processes near the transition temperature, indicating a coexistence of magnetic phases. Magnetic entropy change and the adiabatic temperature change were obtained from heat capacity measurements up to 380 K at magnetic fields of 0 and 5 T. The results show high values of the magnetocaloric properties, as the relative cooling power, even in the presence of the hysteresis. The results can be associated to an increase in chemical pressure by Fe/Cr.

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

    SciTech Connect

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

    2006-01-01

    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.

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

    PubMed Central

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

    1986-01-01

    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

  16. The effects of age on nuclear power plant containment cooling systems

    SciTech Connect

    Lofaro, R.; Subudhi, M.; Travis, R.; DiBiasio, A.; Azarm, A. [Brookhaven National Lab., Upton, NY (United States); Davis, J. [Science Applications International Corp., New York, NY (United States)

    1994-04-01

    A study was performed to assess the effects of aging on the performance and availability of containment cooling systems in US commercial nuclear power plants. This study is part of the Nuclear Plant Aging Research (NPAR) program sponsored by the US Nuclear Regulatory Commission. The objectives of this program are to provide an understanding of the aging process and how it affects plant safety so that it can be properly managed. This is one of a number of studies performed under the NPAR program which provide a technical basis for the identification and evaluation of degradation caused by age. The effects of age were characterized for the containment cooling system by reviewing and analyzing failure data from national databases, as well as plant-specific data. The predominant failure causes and aging mechanisms were identified, along with the components that failed most frequently. Current inspection, surveillance, and monitoring practices were also examined. A containment cooling system unavailability analysis was performed to examine the potential effects of aging by increasing failure rates for selected components. A commonly found containment spray system design and a commonly found fan cooler system design were modeled. Parametric failure rates for those components in each system that could be subject to aging were accounted for in the model to simulate the time-dependent effects of aging degradation, assuming no provisions are made to properly manage it. System unavailability as a function of increasing component failure rates was then calculated.

  17. Diffusion-cooled high-power single-mode waveguide CO2 laser for transmyocardial revascularization

    NASA Astrophysics Data System (ADS)

    Berishvili, I. I.; Bockeria, L. A.; Egorov, E. N.; Golubev, Vladimir S.; Galushkin, Michail G.; Kheliminsky, A. A.; Panchenko, Vladislav Y.; Roshin, A. P.; Sigaev, I. Y.; Vachromeeva, M. N.; Vasiltsov, Victor V.; Yoshina, V. I.; Zabelin, Alexandre M.; Zelenov, Evgenii V.

    1999-01-01

    The paper presents the results on investigations and development of multichannel waveguide CO2 laser with diffusion cooling of active medium excited by discharge of audio-frequency alternating current. The description of high-power single-mode CO2 laser with average beam power up to 1 kW is presented. The result of measurement of the laser basic parameters are offered, as well as the outcomes of performances of the laser head with long active zone, operating in waveguide mode. As an example of application of these laser, various capabilities a description of the developed medical system 'Genom' used in the transmyocardial laser revascularization (TMLR) procedure and clinical results of the possibilities of the TMLR in the surgical treatment are presented.

  18. The prototype fundamental power coupler for the spallation neutron source superconducting cavities : design and initial test results /

    SciTech Connect

    Campisi, I. E.; Daly, E. F.; Davis, G. K.; Drury, M.; Henry, J. E.; Kneisel, P.; Powers, T.; Myneni, G.; Schneider, W; Stirbet, M.; Kang, Y. (Yunghee); Cummings, K. A. (Karen Ann); Wilson, K. M.

    2001-01-01

    Each of the 805 MHz superconducting cavities of the Spallation Neutron Source (SNS) is powered via a coaxial Fundamental Power Coupler (FPC) with a 50 {Omega} impedance and a warm planar alumina window. The design is derived from the experience of other laboratories; in particular, a number of details are based on the coupler developed for the KEK B-Factory superconducting cavities. However, other design features have been modified to account for the fact that the SNS FPC will transfer a considerably lower average power than the KEK-B coupler. Four prototypes have been manufactured so far, and preliminary tests performed on two of them at Los Alamos National Laboratory (LANL). During these tests, peak powers of over 700 kW were transferred through the couplers in the test stand designed and built for this purpose. This paper gives details of the coupler design and of the results obtained from the RF tests on the test stand during the last few months. A more comprehensive set of tests is planned for the near future.

  19. Micro capillary pumped loop system for a cooling high power device

    SciTech Connect

    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

    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)

  20. The maximal cooling power of magnetic and thermoelectric refrigerators with La(FeCoSi)13 alloys

    NASA Astrophysics Data System (ADS)

    Skokov, K. P.; Karpenkov, A. Yu.; Karpenkov, D. Yu.; Gutfleisch, O.

    2013-05-01

    Using our data on magnetic entropy change ?Sm, adiabatic temperature change ?Tad and heat capacity CH for La(FeCoSi)13 alloys, the upper limit of heat Qc transferred per cycle, and the lowest limit of consumed work Wc were established for magnetic refrigerators operating in ??0H =1.9 T. In order to estimate the cooling power, attributable to thermoelectric refrigerators with La(FeCoSi)13, thermal conductivity ?, resistivity ?, and Seebeck coefficient ? were measured and the maximal cooling power QL, the input power Pi, and coefficient of performance have been calculated.

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

    NASA Astrophysics Data System (ADS)

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

    2010-06-01

    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.

  2. Peltier cooling stage utilizing a superconductor-semiconductor junction

    SciTech Connect

    Skertic, M.M.

    1991-04-09

    This paper describes a Peltier cooling stack. It comprises: a first electrode; a superconducting layer electrically coupled to the first electrode; a semiconducting layer electrically coupled to the superconducting layer; and a second superconducting layer electrically coupled to the semiconductor layer; and a second electrode electrically coupled to the second superconducting layer, electrons flowing under an applied voltage from the first electrode through the first superconducting layer, semiconductor layer, second superconducting layer and second electrode, the electrical junction between the first superconducting layer and semiconductor providing Peltier cooling while the electrical junction between the semiconductor layer and the second superconducting layer providing Peltier heating, whereby a cryogenic Peltier cooling stack is provided.

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

    SciTech Connect

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

    1984-09-01

    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.

  4. Sensitivity of Steady-State Temperatures of SF Gas-Cooled-Insulated Power Transformers to Selected Parameters

    Microsoft Academic Search

    Magdy Eteiba; M. M. A. Aziz; J. H. Shazly

    2009-01-01

    The effects of cooling methods, gas pressure, gas velocity, electrical loading, and environmental parameters on the steady-state temperature distribution of SF6 gas-cooled-insulated power transformers are investigated by using the finite-element method. The contributions of convection and radiation to the total heat-transfer rate inside and outside the transformer are included. The results provide useful sensitivity information which can be accessed and

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

    NASA Astrophysics Data System (ADS)

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

    2013-06-01

    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.

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

    NASA Astrophysics Data System (ADS)

    Tamm, Gunnar Olavi

    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.

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

    SciTech Connect

    Daniel S. Wendt; Greg L. Mines

    2010-09-01

    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

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

    SciTech Connect

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

    2010-11-01

    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.

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

    SciTech Connect

    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

    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.

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

    Microsoft Academic Search

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

    2002-01-01

    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

  11. Water-cooled air-conditioning systems for energy and power saving

    Microsoft Academic Search

    R. K. Suri; A. M. R. Al-Marafie; G. P. Maheshwari

    1989-01-01

    The paper presents the results of an experimental investigation to compare the performance of water-cooled and air-cooled air-conditioning systems. Two identical chilled water air-conditioning systems, incorporating air-cooled and water-cooled condensers, were used independently to supply the cooling demand of a space. All other components of the two chillers were identical and of the same make. The chillers were operated on

  12. Behavior of introduced red drum and habitat-use overlap with largemouth bass in a power-plant cooling reservoir 

    E-print Network

    Smith, Robert Clayton

    1989-01-01

    BEHAVIOR OF INTRODUCED RED DRUM AND HABITAT-USE OVERLAP WITH LARGEMOUTH BASS IN A POWER-PLANT COOLING RESERVOIR ROBERT CLAYTON SMITH Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE December 1989 Major Subject: Wildlife and Fisheries Sciences BEHAVIOR OF INTRODUCED RED DRUM AND HABITAT-USE OVERLAP WITH LARGEMOUTH BASS IN A POWER-P~ COOLING RESERVOIR A Thesis by ROBERT CLAYTON SMITH Approved...

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

    DOEpatents

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

    1981-04-21

    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.

  14. Use of beryllium oxide to shape power and reduce void reactivity in gas cooled fast reactors

    SciTech Connect

    Handwerk, C. S.; Driscoll, M. J.; Hejzlar, P. [Massachusetts Inst. of Technology, MIT 24-215, 77 Massachusetts Ave, Cambridge, MA 02139 (United States)

    2006-07-01

    Use of Beryllium Oxide (BeO) as a diluent is explored as a means for both power shaping and void reactivity reduction in fast reactors. A supercritical carbon dioxide (S-CO{sub 2}) cooled fast reactor fueled with Light Water Reactor Transuranics and directly coupled with a Brayton cycle power conversion system is used to investigate the effect of BeO as a diluent. Results show that relatively flat power profiles (peak {<=} 1.22) can be maintained throughout core life using a combination of enrichment and diluent zoning, due to the slight moderating effect of the BeO. Combining BeO diluent with the innovative strategy of using a thick volume of S-CO{sub 2} coolant as the radial reflector yields negative void reactivities throughout core life. The ability to maintain negative coolant void reactivity comes from a combination of the effects of spectral softening due to the BeO diluent and the enhanced leakage upon voiding of the S-CO{sub 2} radial reflector. (authors)

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

    E-print Network

    Burger, R.

    1990-01-01

    OPTIMIZING COOLING TOWER PERFORMANCE REFRIGERATION SYSTEMS, CHEMICAL PLANTS, AND POWER PLANTS ALL HAVE A RESOURCE QUIETLY AWAITING EXPLOITATION - COLD WATER!! ROBERT BURGER President Burger and Associates, Inc. Dallas, Texas Cooling... Evaluation In Compressed Air Systems", Plant Engineering, June 1979. 4. Allied Chemical Corp., "The Pressure Enthalpy Diagram: It's Construction, Use, and Value" . 5. Burger, Robert, "Cooling Tower Technology", Chapter 8, 1979, Revised 1989. 6...

  16. The development of high cooling power and low ultimate temperature superfluid Stirling refrigerators

    NASA Astrophysics Data System (ADS)

    Patel, Ashok B.

    The superfluid Stirling refrigerator (SSR) is a recuperative Stirling cycle refrigerator which provides cooling to below 2 K by using a liquid 3He-4He mixture as the working fluid. In 1990, Kotsubo and Swift demonstrated the first SSR, and by 1995, Brisson and Swift had developed an experimental prototype capable of reaching a low temperature of 296 mK. The goal of this thesis was to improve these capabilities by developing a better understanding of the SSR and building SSR's with higher cooling powers and lower ultimate temperatures. This thesis contains four main parts. In the first part, a numerical analysis demonstrates that the optimal design and ultimate performance of a recuperative Stirling refrigerator is fundamentally different from that of a standard regenerative Stirling refrigerator due to a mass flow imbalance within the recuperator. The analysis also shows that high efficiency recuperators remain a key to SSR performance. Due to a quantum effect called Kapitza resistance, the only realistic and economical method of creating higher efficiency recuperators for use with an SSR is to construct the heat exchangers from very thin (12 ?m - 25 ?m thick) plastic films. The second part of this thesis involves the design and construction of these recuperators. This research resulted in Kapton heat exchangers which are leaktight to superfluid helium and capable of surviving repeated thermal cycling. In the third part of this thesis, two different single stage SSR's are operated to test whether the plastic recuperators would actually improve SSR performance. Operating from a high temperature of 1.0 K and with 1.5% and 3.0% 3He-4He mixtures, these SSR's achieved a low temperature of 291 mK and delivered net cooling powers of 3705 ?W at 750 mK, 977 ?W at 500 mK, and 409 ?W at 400 mK. Finally, this thesis describes the operation of three versions of a two stage SSR. Unfortunately, due to experimental difficulties, the merits of a two stage SSR were not demonstrated and further work is still required. However, despite these difficulties, one of the two stage SSR's was able to reach an ultimate low temperature of 248 mK from a high temperature of 1.03 K. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

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

    PubMed Central

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

    2013-01-01

    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

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

    PubMed

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

    2013-06-01

    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

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

    SciTech Connect

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

    1987-09-01

    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 plant to a commercial sized gasifier based combined cycle power generating facility. Performance of the installation has exceeded the requirements of the Cool Water Program. Performance of the entire oxygen facility is presented at various loadings. Operating ranges of system components are discussed. The oxygen plant back-up system is described and subsequent performance noted. Load following tests were conducted by Airco-BOC and the Cool Water Program to determine the entire facility's operating flexibility. Operating ramp rates achievable on the oxygen plant have exceeded the requirements of the coal gasification facility. The oxygen plant's load-following system is described and results of load-following tests conducted are presented. A supplemental study was conducted to determine alternative oxygen generating facilities to support a nominal 600 MW Texaco gasifier based combined cycle power generation facility. The results of this section of the study are presented. 8 refs., 33 figs., 10 tabs.

  20. 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. ...

  1. Study of using microfiltration and reverse osmosis membrane technologies for reclaiming cooling water in the power industry.

    PubMed

    Li, J; Xu, Z Y; An, H G; Liu, L Q

    2007-07-01

    A study of using dual membrane technologies, microfiltration (MF) and reverse osmosis (RO), for reclaiming blowdown of the cooling tower was conducted at ZJK power plant, Hebei province, China. The study shows that the combined MF-RO system can effectively reduce water consumption in the power industry. The results indicate that MF process is capable of producing a filtrate suitable for RO treatment and achieving a silt density index (SDI) less than 2, turbidity of 0.2 NTU. The water quality of RO effluent is very good with an average conductivity of about 40 micros/cm and rejection of 98%. The product water is suitable for injection into the cooling tower to counteract with cooling water intrusion. After adopting this system, water-saving effectiveness as expressed in terms of cycles of concentration could be increased from 2.5-2.8 times to 5 times. PMID:17710919

  2. PREFACE: Superconducting materials Superconducting materials

    NASA Astrophysics Data System (ADS)

    Charfi Kaddour, Samia; Singleton, John; Haddad, Sonia

    2011-11-01

    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

  3. Biocide usage in cooling towers in the electric power and petroleum refining industries

    Microsoft Academic Search

    J. Veil; J. K. Rice; M. E. S. Raivel

    1997-01-01

    Cooling towers users frequently apply biocides to the circulating cooling water to control growth of microorganisms, algae, and macroorganisms. Because of the toxic properties of biocides, there is a potential for the regulatory controls on their use and discharge to become increasingly more stringent. This report examines the types of biocides used in cooling towers by companies in the electric

  4. powerful way of cooling computer chip using liquid metal with low melting point as the cooling fluid

    Microsoft Academic Search

    Teng Li; Yong-Gang Lv; Jing Liu; Yi-Xin Zhou

    2005-01-01

    With the improvement of computational speed, thermal management becomes a serious concern in\\u000a computer system. CPU chips are squeezing into tighter and tighter spaces with no more room for heat to\\u000a escape. Total power-dissipation levels now reside about 110 W, and peak power densities are reaching\\u000a 400–500 W\\/mm2 and are still steadily climbing. As a result,\\u000a higher performance and greater

  5. ELECTRON COOLING OF RHIC.

    SciTech Connect

    BEN-ZVI, I.; LITVINENKO, V.; BARTON, D.; ET AL.

    2005-05-16

    We report progress on the R&D program for electron-cooling of the Relativistic Heavy Ion Collider (RHIC). This electron cooler is designed to cool 100 GeV/nucleon at storage energy using 54 MeV electrons. The electron source will be a superconducting RF photocathode gun. The accelerator will be a superconducting energy recovery linac. The frequency of the accelerator is set at 703.75 MHz. The maximum electron bunch frequency is 9.38 MHz, with bunch charge of 20 nC. The R&D program has the following components: The photoinjector and its photocathode, the superconducting linac cavity, start-to-end beam dynamics with magnetized electrons, electron cooling calculations including benchmarking experiments and development of a large superconducting solenoid. The photoinjector and linac cavity are being incorporated into an energy recovery linac aimed at demonstrating ampere class current at about 20 MeV.

  6. Microbiologically influenced stress corrosion cracking failure of admiralty brass condenser tubes in a nuclear power plant cooled by freshwater

    Microsoft Academic Search

    T. S Rao; K. V. K Nair

    1998-01-01

    The failure of admiralty brass condenser tubes in a nuclear power plant was investigated. Metallurgical analyses had indicated that stress corrosion cracking (SCC) could have caused the failure. Studies were carried out to see if bacteria could have played a role in bringing about the conditions which resulted in SCC of the tubes. Cooling water (Ranapratap Sagar lake, Kota, Rajasthan)

  7. Steady state heat transfer in a SF6. gas cooled-insulated power transformer using finite element technique

    Microsoft Academic Search

    M. M. Abdel Aziz; M. B. Eteiba; J. H. Shazly

    2006-01-01

    In this paper, the finite element analysis approach is utilized to perform heat transfer analysis to obtain the steady state temperature distribution of SF6 gas cooled-insulated power transformer resulting from conditions imposed on its boundaries, which represents how temperature varies with position in the transformer. The obtained results are compared with measured temperature data collected during the testing program carried

  8. Heat Conduction Problems in Gas Cooled-Insulated Power Transformers Solved by the Finite-Element Method

    Microsoft Academic Search

    Magdy B. Eteiba; Mohamed Mamdouh Abdel Aziz; Jehan Hassan Shazly

    2008-01-01

    In this paper, the finite-element method is used to perform heat transfer analysis to obtain the steady state and the transient temperature distribution of gas cooled-insulated power transformers. All significant parameters that influence transformer operation have been included. Also, the analysis results, which are obtained from the thermal analysis, could be reviewed at any specified location within the transformer as

  9. CLOSED-CYCLE COOLING SYSTEMS FOR STEAM-ELECTRIC POWER PLANTS: A STATE-OF-THE-ART MANUAL

    EPA Science Inventory

    The report, in a practical manual format, gives results of a technical review of the state-of-the-art of thermal pollution control and treatment of cooling water in the steam-electric power generation industry. It assesses current, near horizon, and future technologies utilized o...

  10. Assessment of the suitability of agricultural waste water for geothermal power plant cooling in the Imperial Valley. 1: Water quality

    Microsoft Academic Search

    W. F. Morris; L. P. Rigdon

    1981-01-01

    Evaluation of the quality of agricultural waste water is the first step in assessing the suitability of agricultural waste water for geothermal power plant cooling. Samples of agricultural waste water from the New and Alamo rivers located in the Imperial Valley of California were analyzed. Determinations of standard water quality parameters, solids content, and inorganic compositions of the solids were

  11. Operating Experience and Test Results From An Ammonia-Based Dry/Wet Cooling System For Electric Power Stations 

    E-print Network

    Allemann, R. T.; Werry, E. V.; Fricke, H. D.; Price, R. E.; Bartz, J. A.

    1982-01-01

    . In this concept, the reject heat from the power plant is transferred to liquid ammonia in a steam condenser/ammonia reboiler, rather than by conventional condensation of steam by coolant water. The ammonia vapor generated is subsequently condensed in a cooling...

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

    SciTech Connect

    none,

    1980-01-01

    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.

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

    E-print Network

    Burger, R.

    1991-01-01

    OPTIMIZING COOLING TOWER PERFOnMANCE REFnIGERATION SYSTEMS, CHEMICAL PLANTS, AND POWER PLANTS ALL HAVE A RESOURCE QUIETLY AWAITING EXPLOITATION - COLD WATER!! ROBERT BURGER President Burger and Associates. Inc Dallas, Texas Cooling towers... 62 OPTIMIZING COOLING TOWER PERFOflMANCE REFflIGERATION SYSTEMS, CHEMICAL PLANTS, AND POWER PLANTS ALL HAVE A flESOURCE QUIETLY AWAITING EXPLOITATION COLD WATER!! ROBERT BURGER President Burger and Associates. DaBas, Texas Inc pretty well convinced...

  14. Design study of the cooling scheme for SMES system in ASPCS by using liquid hydrogen

    NASA Astrophysics Data System (ADS)

    Makida, Yasuhiro; Shintomi, Takakazu; Asami, Takuya; Suzuki, Goro; Takao, Tomoaki; Hamajima, Takataro; Tsuda, Makoto; Miyagi, Daisuke; Munakata, Kouhei; Kajiwara, Masataka

    2013-11-01

    From the point of view of environment and energy problems, the renewable energies have been attracting attention. However, fluctuating power generation by the renewable energies affects the stability of the power network. Thus, we propose a new electric power storage and stabilization system, Advanced Superconducting Power Conditioning System (ASPCS), in which a Superconducting Magnetic Energy Storage (SMES) and a hydrogen-energy-storage converge on a liquid hydrogen station for fuel cell vehicles. The ASPCS proposes that the SMES coils wound with MgB2 conductor are indirectly cooled by thermo-siphon circulation of liquid hydrogen to use its cooling capability. The conceptual design of cooling scheme of the ASPCS is presented.

  15. Evaluation of Gas-Cooled Pressurized Phosphoric Acid Fuel Cells for Electric Utility Power Generation

    NASA Technical Reports Server (NTRS)

    Faroque, M.

    1983-01-01

    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.

  16. Optimum Reflector Configurations for Minimizing Fission Power Peaking in a Lithium-Cooled, Liquid-Metal Reactor with Sliding Reflectors

    SciTech Connect

    Fensin, Michael L. [Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL 32611 (United States); Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Poston, David I. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2005-02-06

    Many design constraints limit the development of a space fission power system optimized for fuel performance, system reliability, and mission cost. These design constraints include fuel mass provisions to meet cycle-length requirements, fuel centerline and clad temperatures, and clad creep from fission gas generation. Decreasing the fission power peaking of the reactor system enhances all of the mentioned parameters. This design study identifies the cause, determines the reflector configurations for reactor criticality, and generates worth curves for minimized fission-power-peaking configuration in a lithium-cooled liquid-metal reactor that uses sliding reflectors. Because of the characteristics of the core axial power distribution and axial power distortions inherent to the sliding reflector design, minimizing the power peaking of the reactor involves placing the reflectors in a position that least distorts the axial power distribution. The views expressed in this document are those of the author and do not necessarily reflect agreement by the Government.

  17. Optimum Reflector Configurations for Minimizing Fission Power Peaking in a Lithium-Cooled, Liquid-Metal Reactor with Sliding Reflectors

    NASA Astrophysics Data System (ADS)

    Fensin, Michael L.; Poston, David I.

    2005-02-01

    Many design constraints limit the development of a space fission power system optimized for fuel performance, system reliability, and mission cost. These design constraints include fuel mass provisions to meet cycle-length requirements, fuel centerline and clad temperatures, and clad creep from fission gas generation. Decreasing the fission power peaking of the reactor system enhances all of the mentioned parameters. This design study identifies the cause, determines the reflector configurations for reactor criticality, and generates worth curves for minimized fission-power-peaking configuration in a lithium-cooled liquid-metal reactor that uses sliding reflectors. Because of the characteristics of the core axial power distribution and axial power distortions inherent to the sliding reflector design, minimizing the power peaking of the reactor involves placing the reflectors in a position that least distorts the axial power distribution. The views expressed in this document are those of the author and do not necessarily reflect agreement by the Government.

  18. European roadmap on superconductive electronics - status and perspectives

    NASA Astrophysics Data System (ADS)

    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

    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

  19. 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...

  20. Neutrino Propagation In Color Superconducting Quark Matter

    E-print Network

    Gregory W. Carter; Sanjay Reddy

    2000-05-23

    We calculate the neutrino mean free path in color superconducting quark matter, and employ it to study the cooling of matter via neutrino diffusion in the superconducting phase as compared to a free quark phase. The cooling process slows when quark matter undergoes a second order phase transition to a superconducting phase at the critical temperature $T_c$. Cooling subsequently accelerates as the temperature decreases below $T_c$. This will directly impact the early evolution of a newly born neutron star should its core contain quark matter. Consequently, there may be observable changes in the early neutrino emission which would provide evidence for superconductivity in hot and dense matter.

  1. High power continuous wave microwave test bench at 4.6 GHz for experimental advanced superconducting tokamak

    NASA Astrophysics Data System (ADS)

    Ma, Wendong; Hu, Huaichuan; Shan, Jiafang; Xu, Handong; Wang, Mao; Wu, Zege; Zhu, Liang

    2013-01-01

    The lower hybrid current drive (LHCD) is an effective approach for auxiliary heating and non-inductive current drive in the experimental advanced superconducting tokamak. The 6 MW/4.6 GHz LHCD system is being designed and installed with twenty-four 250 KW/4.6 GHz high power klystron amplifiers. The test bench operating at 250 KW/4.6 GHz in continuous wave mode has been set up, which can test and train microwave components for the 6 MW/4.6 GHz LHCD system. In this paper, the system architecture and software of the microwave test bench are presented. Moreover, the test results of these klystrons and microwave units are described here in detail. The long term operation of the test bench and improved performance of all microwave component samples indicated that the related technologies on test bench can be applied in the large scale LHCD systems.

  2. High power continuous wave microwave test bench at 4.6 GHz for experimental advanced superconducting tokamak.

    PubMed

    Ma, Wendong; Hu, Huaichuan; Shan, Jiafang; Xu, Handong; Wang, Mao; Wu, Zege; Zhu, Liang

    2013-01-01

    The lower hybrid current drive (LHCD) is an effective approach for auxiliary heating and non-inductive current drive in the experimental advanced superconducting tokamak. The 6 MW/4.6 GHz LHCD system is being designed and installed with twenty-four 250 KW/4.6 GHz high power klystron amplifiers. The test bench operating at 250 KW/4.6 GHz in continuous wave mode has been set up, which can test and train microwave components for the 6 MW/4.6 GHz LHCD system. In this paper, the system architecture and software of the microwave test bench are presented. Moreover, the test results of these klystrons and microwave units are described here in detail. The long term operation of the test bench and improved performance of all microwave component samples indicated that the related technologies on test bench can be applied in the large scale LHCD systems. PMID:23387646

  3. A lithium-cooled reactor - Brayton turboelectric power converter design for 100-kWe class space reactor electric systems

    SciTech Connect

    Anderson, R.V.

    1984-08-01

    The conceptual design of a 100-kWe space reactor electric system to satisfy the design goals of the Tri-Agency SP-100 Program has been completed. The system was selected from an initial field of over 500 potential choices covering a wide range of reactor, power converter, shield, heat transport, and radiator subsystems. The selected system -- a lithium-cooled, UN-fueled, refractory-clad reactor coupled to a redundant pair of 110-kWe (gross) Brayton turboelectric power converters -shows strong promise of not only meeting the SP-100 Program design goals but also of providing for substantial growth in power levels for potential future needs.

  4. Magnetocaloric properties and critical behavior of high relative cooling power FeNiB nanoparticles

    NASA Astrophysics Data System (ADS)

    Chaudhary, V.; Maheswar Repaka, D. V.; Chaturvedi, A.; Sridhar, I.; Ramanujan, R. V.

    2014-10-01

    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.

  5. Magnetocaloric properties and critical behavior of high relative cooling power FeNiB nanoparticles

    SciTech Connect

    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

    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.

  6. Nonequilibrium Thermoelectrics: Low-Cost, High-Performance Materials for Cooling and Power Generation

    SciTech Connect

    Li, Q.

    2011-05-18

    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.

  7. Thermal ecology of Naegleria fowleri from a power plant cooling reservoir

    SciTech Connect

    Huizinga, H.W. (Illinois State Univ., Normal (USA)); McLaughlin, G.L. (Univ. of Illinois, Urbana (USA))

    1990-07-01

    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.

  8. Power combiners/dividers for loop pickup and kicker arrays for FNAL stochastic cooling rings

    SciTech Connect

    Johnson, J.K.; Nemetz, R.

    1985-05-01

    The anti-proton accumulator and debuncher at FNAL will use stochastic methods to ''cool'' the beam. Pairs of quarter-wavelength directional-coupler loops are used to detect and kick the beam. The loops are copper plates which are flush with the upper and lower wall of a rectangular beam pipe. The plates, when surrounded by a properly sized pocket, form a 100-ohm transmission-line directional coupler. As the beam passes, a signal which gives position and time information, is induced in the plates. But, because the signal levels are low (<.5 picowatts per pair), a power combiner (usually several primary combiners feeding a secondary combiner) is used to combine the outputs of many loops. Subsequently, the combined signal is amplified, filtered and then fed into a divider, (that is, a combiner operating in reverse). The divider distributes the signal into a different set of loops which modify (kick) the beam's position. Since the loop couplers are arranged linearly, in arrays of various lengths, combiners also provide a convenient method of reducing the number of vacuum feedthroughs and preamplifiers and their related costs in performance and dollars. In this note we describe various stripline combiner systems that add the outputs of 4, 8, 16 or 32 loops.

  9. Superconducting levitating bearing

    NASA Technical Reports Server (NTRS)

    Moon, Francis C. (Inventor)

    1996-01-01

    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.

  10. Cooling through heat pumps powered by a combustion engine for natural gas

    NASA Astrophysics Data System (ADS)

    Janovcová, Martina; Janda?ka, Jozef; Kiš, Roman

    2014-08-01

    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.

  11. Performance and cost of wet and dry cooling systems for pulverized coal power plants with and without carbon capture and storage

    Microsoft Academic Search

    Haibo Zhai; Edward S. Rubin

    2010-01-01

    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

  12. A lithium-cooled reactor - Brayton turboelectric power converter design for 100-kWe class space reactor electric systems

    Microsoft Academic Search

    1984-01-01

    The conceptual design of a 100-kWe space reactor electric system to satisfy the design goals of the Tri-Agency SP-100 Program has been completed. The system was selected from an initial field of over 500 potential choices covering a wide range of reactor, power converter, shield, heat transport, and radiator subsystems. The selected system -- a lithium-cooled, UN-fueled, refractory-clad reactor coupled

  13. Seasonal distribution of hybrid striped bass in a power-plant cooling reservoir and a comparison to red drum

    E-print Network

    Piner, Kevin Ray

    1993-01-01

    of the requirements for the degree of MASTER OF SCIENCE May 1993 Major Subject: Wildlife and Fisheries Science SEASONAL DISTRIBUTION OF HYBRID STRIPED BASS IN A POWER-PLANT COOLING RESERVOIR AND A COMPARISON TO RED DRUM A Thesis by KEVIN RAY PINER Approved... thank my family for the obvious. vi TABLE OF CONTENTS ABSTRACT ACKNOWLEDGEMENTS TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES CHAPTER I INTRODUCTION Page vi viii Openwater Fishery Striped Bass Hybrid Striped Bass Objectives 1 2 4 5...

  14. Exergy analysis of an integrated solid oxide fuel cell and organic Rankine cycle for cooling, heating and power production

    Microsoft Academic Search

    Fahad A. Al-Sulaiman; Ibrahim Dincer; Feridun Hamdullahpur

    2010-01-01

    The study examines a novel system that combined a solid oxide fuel cell (SOFC) and an organic Rankine cycle (ORC) for cooling, heating and power production (trigeneration) through exergy analysis. The system consists of an SOFC, an ORC, a heat exchanger and a single-effect absorption chiller. The system is modeled to produce a net electricity of around 500kW. The study

  15. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    SciTech Connect

    Kent Zammit; Michael N. DiFilippo

    2005-01-01

    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.

  16. Modelization and test of a 500 J superconducting pulsed power transformer

    Microsoft Academic Search

    E. Floch; P. Hiebel; Y. Laumond; A. Lacaze

    1999-01-01

    The aim of this work is to prove the feasibility of pulses through the use of a power transformer. This article presents the design and tests of a 500 J pulsed power transformer. This paper also describes the computer code created to simulate the primary quench development. During the tests, the primary winding was charged to its rated current (500

  17. Helical Muon Beam Cooling Channel Engineering Design

    SciTech Connect

    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

    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.

  18. A near-field scanning microwave microscope based on a superconducting resonator for low power measurements

    NASA Astrophysics Data System (ADS)

    de Graaf, S. E.; Danilov, A. V.; Adamyan, A.; Kubatkin, S. E.

    2013-02-01

    We report on the design and performance of a cryogenic (300 mK) near-field scanning microwave microscope. It uses a microwave resonator as the near-field sensor, operating at a frequency of 6 GHz and microwave probing amplitudes down to 100 {? V}, approaching low enough photon population (N ˜ 1000) of the resonator such that coherent quantum manipulation becomes feasible. The resonator is made out of a miniaturized distributed fractal superconducting circuit that is integrated with the probing tip, micromachined to be compact enough such that it can be mounted directly on a quartz tuning-fork, and used for parallel operation as an atomic force microscope (AFM). The resonator is magnetically coupled to a transmission line for readout, and to achieve enhanced sensitivity we employ a Pound-Drever-Hall measurement scheme to lock to the resonance frequency. We achieve a well localized near-field around the tip such that the microwave resolution is comparable to the AFM resolution, and a capacitive sensitivity down to 6.4 × 10-20 F/sqrt{Hz}, limited by mechanical noise. We believe that the results presented here are a significant step towards probing quantum systems at the nanoscale using near-field scanning microwave microscopy.

  19. Peltier cooling stage utilizing a superconductor-semiconductor junction

    Microsoft Academic Search

    Skertic

    1991-01-01

    This paper describes a Peltier cooling stack. It comprises: a first electrode; a superconducting layer electrically coupled to the first electrode; a semiconducting layer electrically coupled to the superconducting layer; and a second superconducting layer electrically coupled to the semiconductor layer; and a second electrode electrically coupled to the second superconducting layer, electrons flowing under an applied voltage from the

  20. Demonstration and verification tests of 500 m long HTS power cable

    Microsoft Academic Search

    T. Takahashi; H. Suzuki; M. Ichikawa; T. Okamoto; S. Akita; S. Mukoyama; N. Ishii; A. Kimura; K. Yasuda

    2005-01-01

    A high-temperature superconducting (HTS) power transmission cable is considered as one of the next-generation power transmission technologies. The introduction of HTS cables into the actual power grid requires a long-distance cooling tube, due to the location of the cooling stations at intervals of several kilometers along the cable length. Therefore, it is essential to understand the flow property of the

  1. Superconducting magnet

    DOEpatents

    Satti, John A. (Naperville, IL)

    1980-01-01

    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.

  2. Characterizations of power loads on divertor targets for type-I, compound and small ELMs in the EAST superconducting tokamak

    NASA Astrophysics Data System (ADS)

    Wang, L.; Xu, G. S.; Guo, H. Y.; Wang, H. Q.; Liu, S. C.; Gan, K. F.; Gong, X. Z.; Liang, Y.; Yan, N.; Chen, L.; Liu, J. B.; Zhang, W.; Chen, R.; Shao, L. M.; Xiong, H.; Qian, J. P.; Shen, B.; Liu, G. J.; Ding, R.; Zhang, X. J.; Qin, C. M.; Ding, S.; Xiang, L. Y.; Hu, G. H.; Wu, Z. W.; Luo, G. N.; Chen, J. L.; Hu, L. Q.; Gao, X.; Wan, B. N.; Li, J. G.; the EAST Team

    2013-07-01

    The Experimental Advanced Superconducting Tokamak (EAST) has recently achieved a variety of H-mode regimes with different edge-localized mode (ELM) dynamics, including type-I ELMs, compound ELMs, which are manifested by the onset of a large spike followed by a sequence of small spikes on D? emissions, usual type-III ELMs, and very small ELMs. This newly observed very small ELMy H-mode appears to be similar to the type-II ELMy H-mode, with higher repetition frequency (˜1 kHz) and lower amplitude than the type-III ELMy H-mode, exhibiting an intermediate confinement level between type-I and type-III ELMy H-modes. The energy loss and divertor power load are systematically characterized for these different ELMy H-modes to provide a physics basis for the next-step high-power long-pulse operations in EAST. Both type-I and compound ELMs exhibit good confinement (H98(y,2) ˜ 1). A significant loss of the plasma stored energy occurs at the onset of type-I ELMs (˜8%) and compound ELMs (˜5%), while no noticeable change in the plasma stored energy is observed for the small ELMs, including both type-III ELMs and very small ELMs. The peak heat flux on divertor targets for type-I ELMs currently achieved in EAST is about 10 MW m-2, as determined from the divertor-embedded triple Langmuir probe system with high time resolution. As expected, type-III ELMs lead to much smaller divertor power loads with a peak heat flux of about 2 MW m-2. Peak power loads for compound ELMs are between those for type-I and type-III ELMs. It is remarkable that the new very small ELMy H-modes exhibit even lower target power deposition than type-III ELMs, with the peak heat flux generally below 1 MW m-2. These very small ELMs are usually accompanied by broadband fluctuations with frequencies ranging from 20 to 50 kHz, which may promote particle and power exhaust throughout the very small ELMy H-mode regime.

  3. Use of Air2Air Technology to Recover Fresh-Water from the Normal Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants

    SciTech Connect

    Ken Mortensen

    2009-06-30

    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).

  4. Recovery Under Load Performance of 2nd Generation HTS Superconducting Fault Current Limiter for Electric Power Transmission Lines

    Microsoft Academic Search

    Juan-Carlos H. Llambes; Drew W. Hazelton; Charles S. Weber

    2009-01-01

    Development of superconducting fault current limiters (SFCLs) has been pursued for decades and has been limited thermally and\\/or mechanically by the available superconducting materials performance characteristics . However, within the past few years a newer, more robust type of superconductor known as 2G HTS wire, has become available in sufficient quantity and lengths for developers to build prototype devices and

  5. Ampacities of underground electric power cables in the presence of external forced cooling

    SciTech Connect

    Black, W.Z.; Burdick, P.N.

    1982-10-01

    This paper presents a method of computing the ampacity of underground cables that are cooled by external pipes carrying a coolant. The method utilizes conduction shape factors and an effective thermal resistivity which represents the presence of both the surrounding soil and the cooling pipes. When used in place of the native soil resistivity, the effective resistivity value will produce the same cable temperatures as would exist when a cable is buried near external cooling pipes. The effective resistivity value can therefore be used in ampacity tables or existing ampacity programs, thereby extending their application to cases that involve forced cooling. While the method developed is applicable to any cable and cooling pipe geometry, three different cable geometries are examined in detail. An experimental horizontal three-cable/two-pipe system was used to verify the results obtained from the mathematical analysis. The predicted effective thermal resistivities for this system were used in an ampacity program and the resulting conductor temperatures were within a maximum of 3.4 degrees Celsius of the experimentally measured temperatures for conductor temperatures up to 105/sup 0/C.

  6. Improvement of Power System Stability by Use of Superconducting Fault Current Limiter With ZnO Device and Resistor in Parallel

    Microsoft Academic Search

    Y. Shirai; K. Furushiba; Y. Shouno; M. Shiotsu; T. Nitta

    2008-01-01

    Superconducting fault current limiters (SCFCLs) are expected to improve the reliability and stability of power systems. SCFCLs can be classified into R-types (resistive) and L-types (inductive) by the fault current limiting impedance. An L-type FCL is more effective in suppressing the voltage drop during a fault. On the other hand, a R-type FCL is more effective in consuming the acceleration

  7. Economic analysis of wind-powered refrigeration cooling/water-heating systems in food processing. Final report

    SciTech Connect

    Garling, W.S.; Harper, M.R.; Merchant-Geuder, L.; Welch, M.

    1980-03-01

    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.

  8. Joint Optimization of Idle and Cooling Power in Data Centers While Maintaining Response Time

    E-print Network

    Vijaykumar, T. N.

    of the building, servers, air conditioners, power distribution equipment, and electric power. While some of these components are related to peak power (e.g., cost of air conditioners and power distribution equipment Ahmad and T. N. Vijaykumar School of Electrical and Computer Engineering Purdue University {fahmad

  9. High-Temperature Superconductive Cabling Investigated for Space Solar Power Satellites

    NASA Technical Reports Server (NTRS)

    Tew, Roy C.; Juhasz, Albert J.

    2000-01-01

    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).

  10. Expanding the potential for saline formations : modeling carbon dioxide storage, water extraction and treatment for power plant cooling.

    SciTech Connect

    Not Available

    2011-04-01

    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.

  11. Summary of inadequate core cooling instrumentation for US nuclear power plants

    Microsoft Academic Search

    J. L. Anderson; E. W. Hagen; T. C. Morelock

    1990-01-01

    Following the Three Mile Island Unit 2 accident in 1979, the US Nuclear Regulatory Commission (NRC) required significant improvements in instrumentation to detect and monitor recovery from inadequate core cooling (ICC). All pressurized water reactors (PWRs) ultimately were required to have redundant, qualified, Class 1E instrumentation for subcooling margin monitors, core exit thermocouples, and a reactor coolant inventory tracking system.

  12. Brookhaven program to develop a helium-cooled power transmission system

    Microsoft Academic Search

    E. B. Forsyth

    1975-01-01

    The particular system under design consists of flexible cables installed in a cryogenic enclosure at room temperature and cooled to the range 6 to 9 K by supercritical helium; contraction of the cable is accommodated by proper choice of helix angles of the components of the cable. The superconductor is Nb3Sn, and at the present time the dielectric insulation is

  13. Conceptual design of a high temperature power reactor cooled and moderated by supercritical light water

    Microsoft Academic Search

    K. Dobashi; A. Kimura; Y. Oka; S. Koshizuka

    1998-01-01

    A high temperature reactor cooled and moderated by supercritical light water (SCLWR-H) is designed for assessing its technical feasibility and potential economic improvement. The plant system is the once-through direct cycle. Whole core coolant flows to the turbine. When adopting the conventional ascending flow type water rods, the cold coolant flowing up in the water rod is mixed with that

  14. Hydrogen fuel reforming in a fog cooled fuel cell power plant assembly

    Microsoft Academic Search

    A. H. Levy; R. J. Wertheim

    1989-01-01

    This patent describes a high pressure phosphoric acid fuel cell stack assembly. The cell comprising: a stack of fuel cells for producing electricity. The stack including cathode means, anode means, and the stack being formed without a separate cooling system; means for delivering a pressurized air supply to the cathode means; means for delivering a hydrogen rich fuel gas to

  15. Recent Progress on EAST Superconducting Tokamak

    NASA Astrophysics Data System (ADS)

    Li, Jiangang

    2009-11-01

    EAST is the first fully superconducting tokamak with divertor configurations starting operation since 2006. It has now been upgraded from initial full metal wall to actively cooled graphite plasma facing components (PFC) and bakable to 350 C. Stable double null (DN) divertor plasma discharges over 60 seconds have been achieved with the actively cooled graphite PFCs and the new internal divertor cryo-pump. Plasma current up to 600 kA, electron density ˜5x10^19m-3, electron temperature ˜2.5keV have been obtained with lower hybrid current drive (LHCD) and auxiliary heating. Low loop voltage breakdown at 0.15V/m and plasma ramping rate between 0.1MA/s and 0.5MA/s have been obtained with assistance of LHCD. Various start-up scenarios have been explored for operating PF superconducting coils with a large safety margin. Up to 1.2MW LHCD power has been coupled to both SN (single null) and DN plasmas. Divertor performance under long pulse operating conditions has been assessed for both SN and DN configurations. DN operation led to stronger asymmetry in power loading, favoring the outer divertor. Novel wall conditioning techniques, including RF wall conditioning and high frequency RF wall conditioning in the presence of toroidal magnetic fields have also been successfully tested. The details of these recent advances are presented.

  16. High Power Intermodulation Measurements up to 30 W of High Temperature Superconducting Filters

    NASA Technical Reports Server (NTRS)

    Wilker, Charles; Carter, Charles F., III; Shen, Zhi-Yuan

    1999-01-01

    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.

  17. High-powered microwave ablation with a small-gauge gas cooled antenna: Initial ex vivo and in vivo results

    PubMed Central

    Lubner, Meghan G.; Hinshaw, J. Louis; Andreano, Anita; Sampson, Lisa; Lee, Fred T.; Brace, Christopher L.

    2012-01-01

    Purpose To evaluate the performance of a gas-cooled high powered microwave system. Material and Methods 54 ablations were performed in ex vivo bovine livers using three devices: a single 17-gauge cooled radiofrequency(RF) electrode, a cluster RF electrode, and a single 17-gauge gas-cooled microwave (MW)antenna at three time points (n=6 at 4, 12, and 16 min). Radiofrequency power was applied using impedance-based pulsing with maximum 200 W generator output. Microwave power of 135 W at 2.45 GHz was delivered continuously. An approved in vivo study was performed using thirteen domestic pigs. Hepatic ablations were performed using single applicators and the above MW and RF generator systems, at treatment times of 2 (n=7 MW, 6 RF), 5 (n=23 MW, 8 RF), 7 (n=11 MW, 6 RF) and 10 minutes (n=7 MW, 9 RF). Mean transverse diameter and length of the ablation zones were compared using ANOVA with post-hoc t-tests and Wilcoxon rank-sum tests. Results Single ex vivo MW ablations were larger than single RF ablations at all time points (MW mean diameter range 3.5–4.8 cm 4–16 min; RF 2.6–3.1 cm 4–16 min) (p<0.05). There was no difference in mean diameter between cluster RF and MW ablations (RF: 3.3–4.4 cm 4–16 min; P=0.4–0.9). In vivo lesion diameters in cm for MW (and RF) were as follows: 2.6±0.72 (1.5±0.14), 3.6±0.89 (2.0±0.4), 3.4±0.87 (1.8±0.23), and 3.8±0.74 (2.1±0.3) at 2, 5, 7 and 10 min, respectively (p<0.05 all time points). Conclusions Gas-cooled high powered MW ablation allows the generation of large ablation zones in short times. PMID:22277272

  18. Superconducting Cable Termination

    DOEpatents

    Sinha, Uday K. (Carrollton, GA); Tolbert, Jerry (Newnan, GA)

    2005-08-30

    Disclosed is a termination that connects high temperature superconducting (HTS) cable immersed in pressurized liquid nitrogen to high voltage and neutral (shield) external bushings at ambient temperature and pressure. The termination consists of a splice between the HTS power (inner) and shield (outer) conductors and concentric copper pipes which are the conductors in the termination. There is also a transition from the dielectric tape insulator used in the HTS cable to the insulators used between and around the copper pipe conductors in the termination. At the warm end of the termination the copper pipes are connected via copper braided straps to the conventional warm external bushings which have low thermal stresses. This termination allows for a natural temperature gradient in the copper pipe conductors inside the termination which enables the controlled flashing of the pressurized liquid coolant (nitrogen) to the gaseous state. Thus the entire termination is near the coolant supply pressure and the high voltage and shield cold bushings, a highly stressed component used in most HTS cables, are eliminated. A sliding seal allows for cable contraction as it is cooled from room temperature to ˜72-82 K. Seals, static vacuum, and multi-layer superinsulation minimize radial heat leak to the environment.

  19. Current leads cooling for the series-connected hybrid magnets

    NASA Astrophysics Data System (ADS)

    Bai, Hongyu; Marshall, William S.; Bird, Mark D.; Gavrilin, Andrew V.; Weijers, Hubertus W.

    2014-01-01

    Two Series-Connected Hybrid (SCH) magnets are being developed at the National High Magnetic Field Laboratory. Both SCH magnets combine a set of resistive Florida-Bitter coils with a superconducting outsert coil constructed of the cable-in-conduit conductor (CICC). The outsert coils of the two magnets employ 20 kA BSCCO HTS current leads for the power supply although they have different designs and cooling methods. The copper heat exchangers of the HTS current leads for the HZB SCH are cooled with forced flow helium at a supply temperature of 44 K, while the copper heat exchangers of HTS current leads for NHMFL SCH are cooled with liquid nitrogen at a temperature of 78 K in a self-demand boil-off mode. This paper presents the two cooling methods and their impacts on cryogenic systems. Their efficiencies and costs are compared and presented.

  20. Heat Pipe Integrated in Direct Bonded Copper (DBC) Technology for the Cooling of Power Electronics Packaging

    Microsoft Academic Search

    M. Ivanova; Y. Avenas; C. Schaeffer; J. B. Dezord; J. Schulz-Harder

    2005-01-01

    As the power densities of power components continue to grow, thermal issues are becoming extremely important and vital for the product quality. The primary causes of failures in electronic equipment are the excessive temperatures of the critical components, such as semiconductors and transformers. Power systems for space application are usually housed in completely sealed enclosures due to safety reasons. Since

  1. Porous media heat exchangers for cooling of high-power optical components

    Microsoft Academic Search

    John H. Rosenfeld; Mark T. North

    1995-01-01

    Technologies based on porous media can be used in several classes of heat exchangers that can be used to meet the cooling needs of high heat load optical components as well as other high heat flux applications. These include mechanically pumped single-phase and two-phase porous media heat exchangers, as well as capillary pumped (heat pipe) two-phase designs. A brief overview

  2. Electromagnetic and thermal analysis of distributed cooled high power millimeter wave windows

    Microsoft Academic Search

    Scott D. Nelson; Thomas Reitter; Malcolm Caplan; Charles Moeller

    1996-01-01

    The sectional high-frequency internally-cooled window, as proposed by General Atomics(1), has unique potential for allowing microwave sources to reach multi-megawatt CW levels with application to ECRH. Designs are being investigated using computational electromagnetic (EM), thermal, and mechanical codes at 110 GHz and 170 GHz to examine the design tradeoffs between RF performance and thermal mechanical safety margins. The EM analyses

  3. Electromagnetic and thermal analysis of distributed cooled high power millimeter wave windows

    Microsoft Academic Search

    S. D. Nelson; T. Reitter; M. Caplan

    1995-01-01

    The sectional high-frequency internally-cooled window, as proposed by General Atomics, has unique potential for allowing microwave sources to reach multi-megawatt CW levels with application to ECRH. Designs are being investigated using computational electromagnetic (EM), thermal, and mechanical codes at 110 GHz and 170 GHz to examine the design tradeoffs between RF performance and thermal mechanical safety margins. The EM analyses

  4. High-power broad-area diode lasers for laser cooling

    Microsoft Academic Search

    A. C. Fey-den Boer; H. C. W. Beijerinck; K. A. H. van Leeuwen

    1996-01-01

    This work describes an experimental investigation on the applicability of an injection-locked broad-area diode laser for laser cooling, which requires narrow-linewidth light. Unlike diode laser arrays, injection locked broad-area lasers have so far not been demonstrated to operate on a linewidth below 1 MHz. Using a heterodyne technique, we show that the frequency of the master laser is tracked by

  5. Test results on a thermosyphon concept to high-power cool desktop computers and servers

    Microsoft Academic Search

    R. L. Webb; Shinobu Yamauchi; Showa Denko

    2002-01-01

    This paper reports measured thermal performance of two prototype thermo-syphon devices designed to cool desktop computers and servers. The prototype was designed to reject 100 W with 35 K CPU-to-air temperature difference using an 80 mm 3350 rpm fan for air flow. One prototype is aluminum and uses R-134A, while the other is copper and uses water. The working fluid

  6. VIBRATION-INDUCED TWO-PHASE COOLING TECHNOLOGIES FOR HIGH POWER THERMAL MANAGEMENT

    Microsoft Academic Search

    S. Heffington; A. Glezer; S. Tillery; M. Smith

    2004-01-01

    Two technologies for cooling of high-heat flux microelectronics based on enhanced phase-change are described. The first technology is based on a submerged vibration-induced bubble ejection process in which small vapor bubbles that form on and are attached to a submerged heated solid surface are dislodged and propelled into the cooler bulk liquid. This ejection technique involves forced removal of the

  7. Test and simulation of a solar-powered absorption cooling machine

    Microsoft Academic Search

    Alfred Erhard; Erich Hahne

    1997-01-01

    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

  8. Serial and parallel power equipment with high-temperature superconducting elements

    NASA Technical Reports Server (NTRS)

    Bencze, Laszlo; Goebl, Nandor; Palotas, Bela; Vajda, Istvan

    1995-01-01

    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.

  9. Corium Retention for High Power Reactors by An In-Vessel Core Catcher in Combination with External Reactor Vessel Cooling

    SciTech Connect

    Joy L. Rempe; D. L. Knudson; K. G. Condie; K. Y. Suh; F. -B. Cheung; S. -B. Kim

    2004-05-01

    If there were inadequate cooling during a reactor accident, a significant amount of core material could become molten and relocate to the lower head of the reactor vessel, as happened in the Three Mile Island Unit 2 (TMI-2) accident. If it is possible to ensure that the vessel lower head remains intact so that relocated core materials are retained within the vessel, the enhanced safety associated with these plants can reduce concerns about containment failure and associated risk. For example, the enhanced safety of the Westinghouse Advanced 600 MWe Pressurized Water Reactor (AP600), which relied upon External Reactor Vessel Cooling (ERVC) for in-vessel retention (IVR), resulted in the United States Nuclear Regulatory Commission (US NRC) approving the design without requiring certain conventional features common to existing Light Water Reactors (LWRs). Accordingly, IVR of core melt is a key severe accident management strategy adopted by some operating nuclear power plants and proposed for some advanced light water reactors. However, it is not clear that currently-proposed methods to achieve ERVC will provide sufficient heat removal for higher power reactors. A US–Korean International Nuclear Energy Research Initiative (INERI) project has been initiated in which the Idaho National Engineering and Environmental Laboratory (INEEL), Seoul National University (SNU), Pennsylvania State University (PSU), and the Korea Atomic Energy Research Institute (KAERI) will determine if IVR is feasible for reactors up to 1500 MWe. This paper summarizes results from the first year of this 3-year project.

  10. a Compact Cooling System for Hts Power Cable Based on Thermal Siphon for Circulation of LN2

    NASA Astrophysics Data System (ADS)

    Ivanov, Yu.; Radovinsky, A.; Zhukovsky, A.; Sasaki, A.; Watanabe, H.; Kawahara, T.; Yamaguchi, S.

    2010-04-01

    In recent years, the technologies of manufacturing of high-temperature superconducting (HTS) tapes have achieved the critical current of 100 A. An era of industrial application of HTS power supply cables is coming. The liquid nitrogen (LN2) is usually used to keep the HTS cable at low temperature. LN2 must circulate inside the cryopipes, and the pump is used. However, the pump power is one of heat loads for the cryogenic system, and if it is high the effectiveness of the SC cable system decreases. In order to resolve this problem, a thermal siphon can be applied to circulate LN2. One of the possible system configurations have been analyzed recently by Radovinsky and Zhukovsky [1] along the basic idea proposed by S. Yamaguchi as collaboration between Chubu University and MIT. Here, we discuss the effectiveness of thermal siphon with a counter-flow circulation loop composed of a cryogen flow channel and an inner cable channel. Such configuration simplifies apparatus significantly, especially for short-distance applications.

  11. A high-efficiency coaxial pulse tube cryocooler with 500 W cooling capacity at 80 K

    NASA Astrophysics Data System (ADS)

    Hu, J. Y.; Zhang, L. M.; Zhu, J.; Chen, S.; Luo, E. C.; Dai, W.; Li, H. B.

    2014-07-01

    High-temperature superconductivity power-grid technologies require a highly reliable and efficient cryocooler with cooling power of 100 W to kilowatt level at liquid-nitrogen temperatures to produce cryogenic environments. This paper describes the design of a coaxial Stirling-type pulse tube cryocooler to meet this need. In the designed cryocooler, the regenerator and pulse tube are lengthened to avoid possible temperature inhomogeneity. In an experiment, the azimuthal temperature difference at the middle of the regenerator was less than 30 K. With 7.6 kW electric power input, the cryocooler offers more than 520 W cooling power at 80 K corresponding to a relative Carnot efficiency of 18.2%. When the cooling power was less than 370 W, the efficiency is higher than 20%.

  12. Noise Temperature and IF Bandwidth of a 530 GHz Heterodyne Receiver Employing a Diffusion-Cooled Superconducting Hot-Electron Mixer

    NASA Technical Reports Server (NTRS)

    Skalare, A.; McGrath, W. R.; Bumble, B.; LeDuc, H. G.; Burke, P. J.; Verheijen, A. A.; Prober, D. E.

    1995-01-01

    We report on the first heterodyne measurements with a diffusion-cooled hot-electron bolometer mixer in the submillimeter wave band, using a waveguide mixer cooled to 2.2 K. The best receiver noise temperature at a local oscillator frequency of 533 GHz and an intermediate frequency of 1.4 GHz was 650 K (double sideband). The 3 dB IF roll-off frequency was around 1.7 to 1.9 GHz, with a weak dependence on the device bias conditions.

  13. Static forces in a superconducting magnet bearing

    SciTech Connect

    Stoye, P.; Fuchs, G. [Institut fuer Festkoerper- und Werkstofforschung, Dresden (Germany)] [Institut fuer Festkoerper- und Werkstofforschung, Dresden (Germany); Gawalek, W.; Goernert, P. [Institut fuer Physikalische Hochtechnologie, Jena (Germany)] [Institut fuer Physikalische Hochtechnologie, Jena (Germany); Gladun, A. [Technische Univ., Dresden (Germany)] [Technische Univ., Dresden (Germany)

    1995-11-01

    Static levitation forces and stiffnesses in a superconducting bearing consisting of concentric ring magnets and a superconducting YBaCuO ring are investigated. In the field-cooled mode a levitation force of 20 N has been achieved. The axial and radial stiffnesses have values of 15 N/mm and 10 N/mm, respectively. An arrangement with two bearings supporting a high speed shaft is now under development. A possible application of superconducting magnetic bearings is flywheels for energy storage.

  14. ENVIRONMENTAL IMPACT OF THE COOLING WATER INTAKE STRUCTURE, TANGUISSON POWER PLANT

    E-print Network

    Mcilwain, Jenny

    ..................................... 5 Assessment of Threatened and Endangered Species. ............................................................................................................................... 41 Threatened and Endangered Species Laboratory Technical Report No. 111 May 2005 #12;Cover Photo: View of Tanguisson Power Plant from

  15. Direct-Drive Gas-Cooled Reactor Power System: Concept and Preliminary Testing

    NASA Technical Reports Server (NTRS)

    Wright, S. A.; Lipinski, R. J.; Godfroy, T. J.; Bragg-Sitton, S. M.; VanDyke, M. K.

    2002-01-01

    This paper describes the concept and preliminary component testing of a gas-cooled, UN-fueled, pin-type reactor which uses He/Xe gas that goes directly into a recuperated Brayton system to produce electricity for nuclear electric propulsion. This Direct-Drive Gas-Cooled Reactor (DDG) is designed to be subcritical under water or wet- sand immersion in case of a launch accident. Because the gas-cooled reactor can directly drive the Brayton turbomachinery, it is possible to configure the system such that there are no external surfaces or pressure boundaries that are refractory metal, even though the gas delivered to the turbine is 1144 K. The He/Xe gas mixture is a good heat transport medium when flowing, and a good insulator when stagnant. Judicious use of stagnant cavities as insulating regions allows transport of the 1144-K gas while keeping all external surfaces below 900 K. At this temperature super-alloys (Hastelloy or Inconel) can be used instead of refractory metals. Super-alloys reduce the technology risk because they are easier to fabricate than refractory metals, we have a much more extensive knowledge base on their characteristics, and, because they have a greater resistance to oxidation, system testing is eased. The system is also relatively simple in its design: no additional coolant pumps, heat exchanger, or freeze-thaw systems are required. Key to success of this concept is a good knowledge of the heat transfer between the fuel pins and the gas, as well as the pressure drop through the system. This paper describes preliminary testing to obtain this key information, as well as experience in demonstrating electrically heated testing of simulated reactor components.

  16. The Potential Use of Gold in Superconductivity Related Applications

    Microsoft Academic Search

    Eamonn F Maher

    Superconductivity is one of the most remarkable scientific phenomena ever investigated. It is the phenomenon whereby some materials exhibit zero resistance to the passage of an electric current when cooled to low temperatures, and requires a quantum mechanical explanation. Four Nobel prizes in physics have been awarded specifically on the subject of superconductivity, with many more enabled by superconducting technology.

  17. High Speed Water-Cooled Permanent Magnet Motor for Pulse Alternator-Based Pulse Power Systems

    Microsoft Academic Search

    J. E. King; R. M. Kobuck; J. R. Repp

    2008-01-01

    Pulse alternator-based pulse power systems for electromagnetic rail guns store the required energy for powering the rail gun as stored mechanical inertial energy in the rotating member. The pulse alternator (PA) converts the stored inertial energy into electrical energy that is supplied to the rail gun terminals. The losses in the system and energy delivered to the rail gun projectile

  18. Determination of surface resistance and magnetic penetration depth of superconducting YBa2Cu3O(7-delta) thin films by microwave power transmission measurements

    NASA Technical Reports Server (NTRS)

    Bhasin, K. B.; Warner, J. D.; Miranda, F. A.; Gordon, W. L.; Newman, H. S.

    1990-01-01

    A novel waveguide power transmission measurement technique was developed to extract the complex conductivity of superconducting thin films at microwave frequencies. The microwave conductivity was taken of two laser ablated YBa2Cu3O(7-delta) thin films on LaAlO3 with transition temperatures of approx. 86.3 and 82 K, respectively, in the temperature range 25 to 300 K. From the conductivity values, the penetration depth was found to be approx. 0.54 and 0.43 micron, and the surface resistance (R sub s) to be approx. 24 and 36 micro-Ohms at 36 GHz and 76 K for the two films under consideration. The R sub s values were compared with those obtained from the change in the Q-factor of a 36 GHz Te sub 011-mode (OFHC) copper cavity by replacing one of its end walls with the superconducting sample. This technique allows noninvasive characterization of high transition temperature superconducting thin films at microwave frequencies.

  19. The experimental study of a novel cooling system of a power transformer in an urban underground substation

    Microsoft Academic Search

    Wenhao Niu; Guoqiang Zhang; Yimin Jiang; Ru Lu; Xin Wang; Jianzhong Wang

    2010-01-01

    Decades of experience in underground substations indicated that the traditional cooling technologies have their own shortcomings. Therefore, a novel Oil-Evaporative liquid cooling technology is presented. This new cooling technology could be considered as a two-step cooling system, which could effectively transport heat energy from thermal sources underground to radiators on the ground by phase changing of evaporative liquid in an

  20. Experimental Investigation of the Relationship between Operating Temperature and Power Handling Capability of High-Temperature Superconducting Dual-Band Bandpass Filter

    NASA Astrophysics Data System (ADS)

    Satoh, Kei; Takagi, Yuta; Narahashi, Shoichi; Nojima, Toshio

    This paper experimentally investigates the relationship between the operating temperature and the power handling capability (PHC) of a coplanar waveguide (CPW) high-temperature superconducting (HTS) dual-band bandpass filter (DBPF) using a YBCO thin film deposited on a MgO substrate. The PHC is evaluated based on the intermodulation distortion of the HTS-DBPF. Experimental results show that the PHC does not change depending on how signals are input to the passbands of the HTS-DBPF at 50 K, 60 K, and 70 K, which leads to a straightforward design of mobile communication systems.

  1. Stochastic cooling at Fermilab

    SciTech Connect

    Marriner, J.

    1986-08-01

    The topics discussed are the stochastic cooling systems in use at Fermilab and some of the techniques that have been employed to meet the particular requirements of the anti-proton source. Stochastic cooling at Fermilab became of paramount importance about 5 years ago when the anti-proton source group at Fermilab abandoned the electron cooling ring in favor of a high flux anti-proton source which relied solely on stochastic cooling to achieve the phase space densities necessary for colliding proton and anti-proton beams. The Fermilab systems have constituted a substantial advance in the techniques of cooling including: large pickup arrays operating at microwave frequencies, extensive use of cryogenic techniques to reduce thermal noise, super-conducting notch filters, and the development of tools for controlling and for accurately phasing the system.

  2. The impact of water use fees on dispatching and water requirements for water-cooled power plants in Texas.

    PubMed

    Sanders, Kelly T; Blackhurst, Michael F; King, Carey W; Webber, Michael E

    2014-06-17

    We utilize a unit commitment and dispatch model to estimate how water use fees on power generators would affect dispatching and water requirements by the power sector in the Electric Reliability Council of Texas' (ERCOT) electric grid. Fees ranging from 10 to 1000 USD per acre-foot were separately applied to water withdrawals and consumption. Fees were chosen to be comparable in cost to a range of water supply projects proposed in the Texas Water Development Board's State Water Plan to meet demand through 2050. We found that these fees can reduce water withdrawals and consumption for cooling thermoelectric power plants in ERCOT by as much as 75% and 23%, respectively. To achieve these water savings, wholesale electricity generation costs might increase as much as 120% based on 2011 fuel costs and generation characteristics. We estimate that water saved through these fees is not as cost-effective as conventional long-term water supply projects. However, the electric grid offers short-term flexibility that conventional water supply projects do not. Furthermore, this manuscript discusses conditions under which the grid could be effective at "supplying" water, particularly during emergency drought conditions, by changing its operational conditions. PMID:24832169

  3. Foulant characteristics comparison in recycling cooling water system makeup by municipal reclaimed water and surface water in power plant.

    PubMed

    Ping, Xu; Jing, Wang; Yajun, Zhang; Jie, Wang; Shuai, Si

    2015-01-01

    Due to water shortage, municipal reclaimed water rather than surface water was replenished into recycling cooling water system in power plants in some cities in China. In order to understand the effects of the measure on carbon steel corrosion, characteristics of two kinds of foulant produced in different systems were studied in the paper. Differences between municipal reclaimed water and surface water were analyzed firstly. Then, the weight and the morphology of two kinds of foulant were compared. Moreover, other characteristics including the total number of bacteria, sulfate reducing bacteria, iron bacteria, extracellular polymeric substance (EPS), protein (PN), and polysaccharide (PS) in foulant were analyzed. Based on results, it could be concluded that microbial and corrosive risk would be increased when the system replenished by municipal reclaimed water instead of surface water. PMID:25893132

  4. Presence of pathogenic microorganisms in power-plant cooling waters. Report for October 1, 1979-September 30, 1981

    SciTech Connect

    Tyndall, R.L.

    1982-10-01

    Cooling waters from eleven geographically disparate power plants were tested for the presence of Naegleria fowleri and Legionella pneumophila (LDB). Control source waters for each plant were also tested for these pathogens. Water from two of the eleven plants contained pathogenic Naegleria, and infectious Legionella were found in seven of the test sites. Pathogenic Naegleria were not found in control waters, but infectious Legionella were found in five of the eleven control source water sites. Concentrations of nitrite, sulfate, and total organic carbon correlated with the concentrations of LDB. A new species of Legionella was isolated from one of the test sites. In laboratory tests, both Acanthamoeba and Naegleria were capable of supporting the growth of Legionella pneumophila.

  5. Certification of Superconducting Solenoid-Based Focusing Lenses

    SciTech Connect

    DiMarco, E.Joseph; Hemmati, Ali M.; Orris, Darryl F.; Page, Thomas M.; Rabehl, Roger H.; Tartaglia, Michael A.; Terechkine, Iouri; Tompkins, John C.

    2010-07-29

    The first production focusing lens for the HINS beam line at Fermilab has been assembled into a cryostat and tested. A total of 5 devices will be tested before they are installed in the low energy section of the HINS beam line, which uses copper Crossbar-H (CH) style RF cavities. One of the tested CH-section lens assemblies includes a pair of weak orthogonal steering dipoles nested within a strong focusing solenoid, and has six vapor cooled power leads. The other device has only the strong focusing solenoid, and utilizes a single pair of HTS power leads. The production test program is designed to measure the thermal performance of the cryostat, minimum cooling requirements for the HTS leads, quench performance of all superconducting components, and precise determination of the magnetic axis and field angles. Results and future plans for the first production device tests are presented.

  6. Constraints on molecular gas in cooling flows and powerful radio galaxies

    NASA Technical Reports Server (NTRS)

    O'Dea, Christopher P.; Baum, Stefi A.; Maloney, Philip R.; Tacconi, Linda J.; Sparks, William B.

    1994-01-01

    We searched for molecular gas in a heterogeneous sample of five radio-loud galaxies (three of which are inferred to be in cooling flow clusters) using the Swedish-European Southern Observatory (Swedish-ESO) Submillimeter Telescope. We do not detect CO in emission in any of the cluster sources at a 3 sigma level of typically 15 mK. White et al. (1991) have suggested column densities of N(sub H) approximately 10(exp 21)/sq cm in these clusters with a spatial covering factor of order unity and a total mass of M approximately 10(exp 12) solar mass. Our limits are inconsistent with these column densities and spatial covering factor unless the molecular gas is very cold (kinetic temperature close to 2.7 K) or there only a few clouds along each line of sight. We estimate minimum temperatures in the range approximately 20-30 K. We find that clouds of atomic and molecular hydrogen require strict fine-tuning of parameter space in order to satisfy the requirements for the large column densities N(sub H) approximately 10(exp 21)/sq cm, unit covering factor, and a small number of clouds along the line of sight. Currently the only way molecular gas can be responsible for the X-ray absorption and still be consistent with our observations is if (1) there is of order one cloud along the line of sight and (2) the optical depth in C-12 1 to 0 is less than 10. In addition, we present a Very Large Array (VLA) image of NGC 4696 which suggests this object is a member of the class of 'amorphous cooling flow radio sources.' The C-12 1 to 0 line is detected in emission in PKS 0634-206, a classical double radio galaxy which is rich in extended optical emission line gas. The estimated molecular gas mass is M(sub mol) approximately 3 x 10(exp 9) solar mass and is much larger than that of the ionized component detected in hydrogen alpha suggesting that the emission-line nebula is radiation bounded.

  7. Superconducting and conventional machines

    NASA Astrophysics Data System (ADS)

    Campbell, A. M.

    2014-12-01

    A general comparison is made between conventional and superconducting machines using simple semi-quantitative arguments. A basic conventional machine with sinusoidal currents round rotor and stator is analysed analytically and expressions for the power per unit volume found. Typically about 50 MW per cubic metre of rotor can be obtained and the ratio of power to loss is approximatelythe square of the ratio of the diameter to the skin depth of copper. For a superconducting rotor the power depends on BJc which for YBCO is a maximum at 2 T. If this field could be achieved by the stator a superconducting rotor could be several orders of magnitude smaller than a conventional one. However this is very difficult to achieve. At 50 Hz AC losses are a major problem. Hysteresis losses depend on the ratio of the conductor thickness to the rotor radius so striating the conductor is desirable but low coupling losses requires a twist pitch significantly smaller than the penetration depth. The maximum power is proportional to the product of the rotor and stator currents and the main advantage of superconductors is their very high current density. Therefore the ultimate goal is to have both superconducting, but AC losses in the stator make this difficult. However replacing just the rotor conductors in a synchronous machine gives significant reductions in size and weight for a given power by increasing the electric loading.

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

    Microsoft Academic Search

    Gunnar Olavi Tamm

    2003-01-01

    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,

  9. Solid sorption heat powered cycles for cooling and heat pumping applications

    Microsoft Academic Search

    F. Meunier

    1998-01-01

    Heat powered solid sorption is a feasible alternative to electrical vapour compression. However, the emergence of that technology takes time. In this review, the possibilities and limits of this technology are analysed. The performances are shown to be very interesting and in progress, and right now applications are foreseen. The use of waste heat for solid sorption air-conditioning may be

  10. APPLICATION OF STRUCTURAL MATERIALS IN WATER-COOLED POWER REACTORS (SURVEY REPORT)

    Microsoft Academic Search

    Schimmel

    1962-01-01

    The requirements which structural materials must satisfy for utilization ; in power reactors are reviewed. The properties of materials used for reactor ; pressure vessels are discussed. Load-bearing materials, instrument components, ; shaft materials, and spring materials are also reviewed. 10 references. ; (J.S.R.);

  11. Assessment of cooling water supply in the United States. [Thermal power plants

    Microsoft Academic Search

    D. E. Peterson; J. C. Jr. Sonnichsen

    1977-01-01

    Consistent with the Water Pollution Act of 1965 the Clear Water Restoration Act of 1966, and the Federal Water Pollution Act Amendment of 1972, and realizing the importance of long-range planning, studies were performed to examine the effect of the legislation on the methods of waste management for thermal power plants. Streams in eight major drainage areas in the United

  12. Solar Central Receiver Hybrid Power Systems sodium-cooled receiver concept. Final report. Volume III. Appendices

    SciTech Connect

    None

    1980-01-01

    The overall, long term objective of the Solar Central Receiver Hybrid Power System is to identify, characterize, and ultimately demonstrate the viability and cost effectiveness of solar/fossil, steam Rankine cycle, hybrid power systems that: (1) consist of a combined solar central receiver energy source and a nonsolar energy source at a single, common site, (2) may operate in the base, intermediate, and peaking capacity modes, (3) produce the rated output independent of variations in solar insolation, (4) provide a significant savings (50% or more) in fuel consumpton, and (5) produce power at the minimum possible cost in mills/kWh. It is essential that these hybrid concepts be technically feasible and economically competitive with other systems in the near to mid-term time period (1985-1990) on a commercial scale. The program objective for Phase I is to identify and conceptually characterize solar/fossil steam Rankine cycle, commercial-scale, power plant systems that are economically viable and technically feasible. This volume contains appendices to the conceptual design and systems analysis studies gien in Volume II, Books 1 and 2. (WHK)

  13. Simple strategies for minimization of cooling water usage in binary power plants

    Microsoft Academic Search

    C. J. Bliem; G. L. Mines

    1989-01-01

    The geothermal resources which could be used for the production of electrical power in the United States are located for the most part in the semi-arid western regions of the country. The availability of ground or surface water in the quantity or quality desired for a conventional wet'' heat rejections system represents a barrier to the development of these resources

  14. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    SciTech Connect

    Michael N. DiFilippo

    2004-08-01

    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. Deliverable 1 presents a general assessment of produced water generation in the San Juan Basin in Four Corners Area of New Mexico. Oil and gas production, produced water handling and disposal, and produced water quantities and chemistry are discussed. Legislative efforts to enable the use of this water at SJGS are also described.

  15. Superconducting Cable

    DOEpatents

    Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

    2005-07-22

    In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

  16. Superconducting Cable

    DOEpatents

    Hughey, Raburn L. (Franklin, GA); Sinha, Uday K. (Carrollton, GA); Reece, David S. (Carrollton, GA); Muller, Albert C. (Eidson, TN)

    2005-03-08

    In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith.

  17. Start-up fuel and power flattening of sodium-cooled candle core

    SciTech Connect

    Takaki, Naoyuki; Sagawa, Yu; Umino, Akitake [Department of Nuclear Safety Engineering, Tokyo City University 1-28-1 Tamazutsumi, Setagaya, Tokyo 158-8557 (Japan); Sekimoto, Hiroshi [University of California, Berkeley, CA 94720 (United States)

    2013-07-01

    The hard neutron spectrum and unique power shape of CANDLE enable its distinctive performances such as achieving high burnup more than 30% and exempting necessity of both enrichment and reprocessing. On the other hand, they also cause several challenging problems. One is how the initial fuel can be prepared to start up the first CANDLE reactor because the equilibrium fuel composition that enables stable CANDLE burning is complex both in axial and radial directions. Another prominent problem is high radial power peaking factor that worsens averaged burnup, namely resource utilization factor in once-through mode and shorten the life time of structure materials. The purposes of this study are to solve these two problems. Several ideas for core configurations and startup fuel using single enrichment uranium and iron as a substitute of fission products are studied. As a result, it is found that low enriched uranium is applicable to ignite the core but all concepts examined here exceeded heat limits. Adjustment in enrichment and height of active and burnt zone is opened for future work. Sodium duct assemblies and thorium fuel assemblies loaded in the center region are studied as measures to reduce radial power peaking factor. Replacing 37 fuels by thorium fuel assemblies in the zeroth to third row provides well-balanced performance with flattened radial power distribution. The CANDLE core loaded with natural uranium in the outer and thorium in the center region achieved 35.6% of averaged burnup and 7.0 years of cladding life time owing to mitigated local fast neutron irradiation at the center. Using thorium with natural or depleted uranium in CANDLE reactor is also beneficial to diversifying fission resource and extending available term of fission energy without expansion of needs for enrichment and reprocessing.

  18. USE OF PRODUCED WATER IN RECIRCULATING COOLING SYSTEMS AT POWER GENERATING FACILITIES

    SciTech Connect

    Michael N. DiFilippo

    2004-08-01

    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. Deliverable 2 focuses on transportation--the largest obstacle to produced water reuse in the San Juan Basin (the Basin). Most of the produced water in the Basin is stored in tanks at the well head and must be transported by truck to salt water disposal (SWD) facilities prior to injection. Produced water transportation requirements from the well head to SJGS and the availability of existing infrastructure to transport the water are discussed in this deliverable.

  19. Characteristics of Model Windings of High-TC Superconducting Transformer for Railway Rolling Stock

    NASA Astrophysics Data System (ADS)

    Kamijo, H.; Hata, H.; Fujimoto, H.; Bohno, T.; Sakaki, K.; Yamada, H.; Iwakuma, M.; Funaki, K.

    2004-06-01

    We investigated the possibility of applying high-TC superconducting traction transformer to a rolling stock. In order to achieve a lightweight design, the traction transformer needs to have a special winding structure unlike the experimental high-TC superconducting power transformers fabricated so far. The windings of the traction transformer need to be arranged as closely as possible in a high magnetic field. Then, we fabricated two high-TC superconducting coils that simulated the winding of a high-TC superconducting traction transformer. One is a multi-layer solenoid coil that simulated the primary winding of the transformer. This coil has five layers of a single Bi2Sr2Ca2Cu3Ox (Bi2223) superconducting tape. The other is a close solenoid coil that simulated the secondary winding of the transformer. This coil has one layer of eight parallel Bi2223 superconducting tapes. In this study, we measured the voltage-current, AC loss, current sharing and over current characteristics of these coils cooled by saturated and subcooled liquid nitrogen.

  20. SUPERCONDUCTING RING CYCLOTRON FOR RIKEN RI BEAM FACTORY IN JAPAN

    SciTech Connect

    Okuno, H.; Dantsuka, T.; Yamada, K.; Kase, M.; Maie, T.; Kamigaito, O. [RIKEN Nishina Center, Wako, Saitama, 351-0198 (Japan)

    2010-04-09

    Since 1997, RIKEN Nishina Center has been constructing the Radioactive Isotope Beam Factory (RIBF) and succeeded in beam commissioning of its accelerator complex at the end of 2006. The world's first superconducting ring cyclotron (SRC) is the final booster in the RIBF accelerator complex which is able to accelerate all-element heavy ions to a speed of about 70% of the velocity of light. The ring cyclotron consists of 6 major superconducting sector magnets with a maximum field of 3.8 T. The total stored energy is 235 MJ, and its overall sizes are 19 m diameter, 8 m height and 8,300 tons. The magnet system assembly was completed in August 2005, and successfully reached the maximum field in November 2005. The first beam was extracted at the end of 2006 and the first uranium beam was extracted in March 2007. However operation of the helium refrigerator was not satisfactory although the commissioning of SRC was successful. Operation was stopped every two month due to degradation of its cooling power. In February 2008 the reason of the degradation was revealed to be oil contamination. Operation of the cryogenic system was restarted from August 2008 after hard task to clean up the helium refrigerator and to add oil separators to the compressor. After restoration long-term steady operation to keep the magnet superconducting continued for about 8 months with no sign of degradation of cooling capacity.

  1. Impact of E × B flow shear on turbulence and resulting power fall-off width in H-mode plasmas in experimental advanced superconducting tokamak

    NASA Astrophysics Data System (ADS)

    Yang, Q. Q.; Xu, G. S.; Zhong, F. C.; Wang, L.; Wang, H. Q.; Chen, R.; Yan, N.; Liu, S. C.; Chen, L.; Jia, M. N.; Li, Y. L.; Liu, J. B.

    2015-06-01

    The power fall-off width in the H-mode scrape-off layer (SOL) in tokamaks shows a strong inverse dependence on the plasma current, which was noticed by both previous multi-machine scaling work [T. Eich et al., Nucl. Fusion 53, 093031 (2013)] and more recent work [L. Wang et al., Nucl. Fusion 54, 114002 (2014)] on the Experimental Advanced Superconducting Tokamak. To understand the underlying physics, probe measurements of three H-mode discharges with different plasma currents have been studied in this work. The results suggest that a higher plasma current is accompanied by a stronger E × B shear and a shorter radial correlation length of turbulence in the SOL, thus resulting in a narrower power fall-off width. A simple model has also been applied to demonstrate the suppression effect of E × B shear on turbulence in the SOL and shows relatively good agreement with the experimental observations.

  2. Navy superconductivity efforts

    Microsoft Academic Search

    D. U. Gubser

    1990-01-01

    Both the new high temperature superconductors (HTS) and the low temperature superconductors (LTS) are important components of Navy's total plan to integrate superconductivity into field operational systems. Fundamental research is an important component of the total Navy program and focuses on the HTS materials. Power applications (ship propulsion, etc.) use LTS materials while space applications (MMW electronics, etc.) use HTS

  3. US Navy superconductivity program

    Microsoft Academic Search

    Donald U. Gubser

    1991-01-01

    Both the new high temperature superconductors (HTS) and the low temperature superconductors (LTS) are important components of the Navy's total plan to integrate superconductivity into field operational systems. Fundamental research is an important component of the total Navy program and focuses on the HTS materials. Power applications (ship propulsion) use LTS materials while space applications (millimeter wave electronics) use HTS

  4. Greenhouse gas emission and exergy assessments of an integrated organic Rankine cycle with a biomass combustor for combined cooling, heating and power production

    Microsoft Academic Search

    Fahad A. Al-Sulaiman; Feridun Hamdullahpur; Ibrahim Dincer

    2011-01-01

    In this study, greenhouse gas emission and exergy assessments of an integrated organic Rankine cycle (ORC) with a biomass combustor for combined cooling, heating, and power production as a trigeneration system are conducted. This trigeneration system consists of a biomass combustor, an ORC, a single-effect absorption chiller, and a heat exchanger. Four special cases are considered in this comprehensive study,

  5. High Magnetic Field Superconducting Magnet for 400 MHz Nuclear Magnetic Resonance Spectrometer

    Microsoft Academic Search

    Qiuliang Wang; Baozhi Zhao; Shousen Song; Junsheng Cheng; Yi Li; Yuanzhong Lei; Yinming Dai; Shunzhong Chen; Hui Wang; Housheng Wang; Xinning Hu; Chunyan Cui; Haoyang Liu; Zengren Dong; Chunzhong Wang; Zhipeng Ni; Houcheng Huang; Hongjie Zhang; Luguang Yan; Jianghua Wang

    2011-01-01

    A superconducting magnet with the center field of 9.4 T is designed and fabricated for 400 MHz Nuclear Magnetic Resonance. Superconducting coil with NbTi\\/Cu superconducting wire is employed and cooled by re-condensed liquid helium and the magnet system with the clear-bore of 54 mm. The pulsed tube refrigerator with separated valve is employed to cool the magnet system. The superconducting

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

    SciTech Connect

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

    2002-01-01

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

  7. Design and operating experience of an ac-dc power converter for a superconducting magnetic energy storage unit

    SciTech Connect

    Boenig, H.J.; Nielsen, R.G.; Sueker, K.H.

    1984-01-01

    The design philosophy and the operating behavior of a 5.5 kA, +-2.5 kV converter, being the electrical interface between a high voltage transmission system and a 30 MJ superconducting coil, are documented in this paper. Converter short circuit tests, load tests under various control conditions, dc breaker tests for magnet current interruption, and converter failure modes are described.

  8. Electronic Cooling in Graphene

    Microsoft Academic Search

    R. Bistritzer; A. H. MacDonald

    2009-01-01

    Energy transfer to acoustic phonons is the dominant low-temperature cooling channel of electrons in a crystal.For cold neutral graphene we find that the weak cooling power of its acoustical modes relative to the heat capacity of the system leads to a power law decay of the electronic temperature when far from equilibrium. For heavily doped graphene a high electronic temperature

  9. Can black-hole neutrino-cooled disks power short gamma-ray bursts?

    E-print Network

    Liu, Tong; Hou, Shu-Jin; Gu, Wei-Min

    2015-01-01

    Stellar-mass black holes (BHs) surrounded by neutrino-dominated accretion flows (NDAFs) are the plausible candidates to power gamma-ray bursts (GRBs) via neutrinos emission and their annihilation. The progenitors of short-duration GRBs (SGRBs) are generally considered to be compact binaries mergers. According to the simulation results, the disk mass of the NDAF has been limited after merger events. We can estimate such disk mass by using the current SGRB observational data and fireball model. The results show that the disk mass of a certain SGRB mainly depends on its output energy, jet opening angle, and central BH characteristics. Even for the extreme BH parameters, some SGRBs require massive disks, which approach or exceed the limits in simulations. We suggest that there may exist alternative magnetohydrodynamic processes or some mechanisms increasing the neutrino emission to produce SGRBs with the reasonable BH parameters and disk mass.

  10. Can Black Hole Neutrino-cooled Disks Power Short Gamma-Ray Bursts?

    NASA Astrophysics Data System (ADS)

    Liu, Tong; Lin, Yi-Qing; Hou, Shu-Jin; Gu, Wei-Min

    2015-06-01

    Stellar-mass black holes (BHs) surrounded by neutrino-dominated accretion flows (NDAFs) are plausible sources of power for gamma-ray bursts (GRBs) via neutrino emission and their annihilation. The progenitors of short-duration GRBs (SGRBs) are generally considered to be compact binary mergers. According to the simulation results, the disk mass of the NDAF is limited after merger events. We can estimate such disk masses using the current SGRB observational data and fireball model. The results show that the disk mass of a certain SGRB mainly depends on its output energy, jet opening angle, and central BH characteristics. Even for the extreme BH parameters, some SGRBs require massive disks, which approach or exceed the limits in simulations. We suggest that there may exist alternative MHD processes or mechanisms that increase the neutrino emission to produce SGRBs with reasonable BH parameters and disk masses.

  11. Interface superconductivity

    NASA Astrophysics Data System (ADS)

    Gariglio, S.; Gabay, M.; Mannhart, J.; Triscone, J.-M.

    2015-07-01

    Low dimensional superconducting systems have been the subject of numerous studies for many years. In this article, we focus our attention on interfacial superconductivity, a field that has been boosted by the discovery of superconductivity at the interface between the two band insulators LaAlO3 and SrTiO3. We explore the properties of this amazing system that allows the electric field control and on/off switching of superconductivity. We discuss the similarities and differences between bulk doped SrTiO3 and the interface system and the possible role of the interfacially induced Rashba type spin-orbit. We also, more briefly, discuss interface superconductivity in cuprates, in electrical double layer transistor field effect experiments, and the recent observation of a high Tc in a monolayer of FeSe deposited on SrTiO3.

  12. Application of Pulsed Electrical Fields for Advanced Cooling and Water Recovery in Coal-Fired Power Plant

    SciTech Connect

    Young Cho; Alexander Fridman

    2009-04-02

    The overall objective of the present work was to develop technologies to reduce freshwater consumption in a cooling tower of coal-based power plant so that one could significantly reduce the need of make-up water. The specific goal was to develop a scale prevention technology based an integrated system of physical water treatment (PWT) and a novel filtration method so that one could reduce the need for the water blowdown, which accounts approximately 30% of water loss in a cooling tower. The present study investigated if a pulsed spark discharge in water could be used to remove deposits from the filter membrane. The test setup included a circulating water loop and a pulsed power system. The present experiments used artificially hardened water with hardness of 1,000 mg/L of CaCO{sub 3} made from a mixture of calcium chloride (CaCl{sub 2}) and sodium carbonate (Na{sub 2}CO{sub 3}) in order to produce calcium carbonate deposits on the filter membrane. Spark discharge in water was found to produce strong shockwaves in water, and the efficiency of the spark discharge in cleaning filter surface was evaluated by measuring the pressure drop across the filter over time. Results showed that the pressure drop could be reduced to the value corresponding to the initial clean state and after that the filter could be maintained at the initial state almost indefinitely, confirming the validity of the present concept of pulsed spark discharge in water to clean dirty filter. The present study also investigated the effect of a plasma-assisted self-cleaning filter on the performance of physical water treatment (PWT) solenoid coil for the mitigation of mineral fouling in a concentric counterflow heat exchanger. The self-cleaning filter utilized shockwaves produced by pulse-spark discharges in water to continuously remove scale deposits from the surface of the filter, thus keeping the pressure drop across the filter at a relatively low value. Artificial hard water was used in the present fouling experiments for three different cases: no treatment, PWT coil only, and PWT coil plus self-cleaning filter. Fouling resistances decreased by 59-72% for the combined case of PWT coil plus filter compared with the values for no-treatment cases. SEM photographs showed much smaller particle sizes for the combined case of PWT coil plus filter as larger particles were continuously removed from circulating water by the filter. The x-ray diffraction data showed calcite crystal structures for all three cases.

  13. Analysis of N-16 concentration in primary cooling system of AP1000 power reactor

    NASA Astrophysics Data System (ADS)

    Rohanda, Anis; Waris, Abdul

    2015-04-01

    Nitrogen-16 (N-16) is one of the radiation safety parameter on the primary reactor system. The activation product, N-16, is the predominant contributor to the activity in the reactor coolant system during reactor operation. N-16 is activation product derived from activation of O-16 with fast neutron based on 16O(n,p)16N reaction. Thus study is needed and it performs to determine N-16 concentration in reactor coolant (primary coolant) in supporting radiation safety. One of the way is using analytical methode based on activation and redecay princip to obtain N-16 concentration. The analysis was performed on the configuration basis and operational of Westinghouse AP1000 power reactor in several monitoring points at coolant reactor system. The results of the calculation of N-16 concentration at the core outlet, reactor vessel outlet, pressurizer line, inlet and outlet of steam generators, primary pumps, reactor vessels inlet and core inlet are: 281, 257, 255, 250, 145, 142, 129 and 112 µCi/gram respectively. The results of analysis compared with AP1000 design control document as standard values. The verification showed very high accuracy comparation between analytical results and standard values.

  14. Internet Based, GIS Catalog of Non-Traditional Sources of Cooling Water for Use at America's Coal-Fired Power Plants

    SciTech Connect

    J. Daniel Arthur

    2011-09-30

    In recent years, rising populations and regional droughts have caused coal-fired power plants to temporarily curtail or cease production due to a lack of available water for cooling. In addition, concerns about the availability of adequate supplies of cooling water have resulted in cancellation of plans to build much-needed new power plants. These issues, coupled with concern over the possible impacts of global climate change, have caused industry and community planners to seek alternate sources of water to supplement or replace existing supplies. The Department of Energy, through the National Energy Technology Laboratory (NETL) is researching ways to reduce the water demands of coal-fired power plants. As part of the NETL Program, ALL Consulting developed an internet-based Catalog of potential alternative sources of cooling water. The Catalog identifies alternative sources of water, such as mine discharge water, oil and gas produced water, saline aquifers, and publicly owned treatment works (POTWs), which could be used to supplement or replace existing surface water sources. This report provides an overview of the Catalog, and examines the benefits and challenges of using these alternative water sources for cooling water.

  15. Numerical Model for Conduction-Cooled Current Lead Heat Loads

    SciTech Connect

    White, M.J.; Wang, X.L.; /Fermilab; Brueck, H.D.; /DESY

    2011-06-10

    Current leads are utilized to deliver electrical power from a room temperature junction mounted on the vacuum vessel to a superconducting magnet located within the vacuum space of a cryostat. There are many types of current leads used at laboratories throughout the world; however, conduction-cooled current leads are often chosen for their simplicity and reliability. Conduction-cooled leads have the advantage of using common materials, have no superconducting/normal state transition, and have no boil-off vapor to collect. This paper presents a numerical model for conduction-cooled current lead heat loads. This model takes into account varying material and fluid thermal properties, varying thicknesses along the length of the lead, heat transfer in the circumferential and longitudinal directions, electrical power dissipation, and the effect of thermal intercepts. The model is validated by comparing the numerical model results to ideal cases where analytical equations are valid. In addition, the XFEL (X-Ray Free Electron Laser) prototype current leads are modeled and compared to the experimental results from testing at DESY's XFEL Magnet Test Stand (XMTS) and Cryomodule Test Bench (CMTB).

  16. USERDA Division of Electric Energy Systems dc superconducting power transmission line project at LASL. Progress report No. 15, October 1, 1975September 30, 1976. [100kV, 5 GW dc

    Microsoft Academic Search

    F. J. Edeskuty; P. Chowdhuri

    1977-01-01

    This annual progress report of the Los Alamos Scientific Laboratory dc Superconducting Power Transmission Line (SPTL) Development Project covers the period October 1975 to September 1976. Progress in the electrical, cryogenic, and superconductor design for a 100-kV, 5-GW dc SPTL is described.

  17. Superconducting PM undiffused machines with stationary superconducting coils

    DOEpatents

    Hsu, John S.; Schwenterly, S. William

    2004-03-02

    A superconducting PM machine has a stator, a rotor and a stationary excitation source without the need of a ferromagnetic frame which is cryogenically cooled for operation in the superconducting state. PM material is placed between poles on the rotor to prevent leakage or diffusion of secondary flux before reaching the main air gap, or to divert PM flux where it is desired to weaken flux in the main air gap. The PM material provides hop-along capability for the machine in the event of a fault condition.

  18. Cooling Capacity Optimization: Calculation of Hardening Power of Aqueous Solution Based on Poly(N-Vinyl-2-Pyrrolidone)

    NASA Astrophysics Data System (ADS)

    Koudil, Z.; Ikkene, R.; Mouzali, M.

    2013-11-01

    Polymer quenchants are becoming increasingly popular as substitutes for traditional quenching media in hardening metallic alloys. Water-soluble organic polymer offers a number of environmental, economic, and technical advantages, as well as eliminating the quench-oil fire hazard. The close control of polymer quenchant solutions is essential for their successful applications, in order to avoid the defects of structure of steels, such as shrinkage cracks and deformations. The aim of the present paper is to evaluate and optimize the experimental parameters of polymer quenching bath which gives the best behavior quenching process and homogeneous microstructure of the final work-piece. This study has been carried out on water-soluble polymer based on poly(N-vinyl-2-pyrrolidone) PVP K30, which does not exhibit inverse solubility phenomena in water. The studied parameters include polymer concentration, bath temperature, and agitation speed. Evaluation of cooling power and hardening performance has been measured with IVF SmartQuench apparatus, using standard ISO Inconel-600 alloy. The original numerical evaluation method has been introduced in the computation software called SQ Integra. The heat transfer coefficients were used as input data for calculation of microstructural constituents and the hardness profile of cylindrical sample.

  19. Improved temperature retrieval methods for the validation of a hydrodynamic simulation of a partially frozen power plant cooling lake

    NASA Astrophysics Data System (ADS)

    Casterline, May V.; Salvaggio, Carl; Garrett, Alfred J.; Bartlett, Brent D.; Faulring, Jason W.; Salvaggio, Philip S.

    2010-05-01

    The ALGE code is a hydrodynamic model developed by Savannah River National Laboratory (SRNL) to derive the power output levels of an electric generation facility from observing the associated cooling pond with an aerial imaging platform. Over the past two years work has been completed to extend the capabilities of the model to incorporate snow and ice as possible phenomena in the modeled environment. In order to validate the extension of the model, intensive ground truth data as well as high-resolution aerial infrared imagery were collected during the winters of 2008-2009 and 2009-2010, for a combined eight months of data collection. Due to the harsh and extreme environmental conditions automatic data collection instruments were designed and deployed. Based on experience gained during the first collection season and equipment design failures, overhauls in the design and operation of the automated data collection buoys were performed. In addition, a more thorough and robust twofold calibration technique was implemented within the aerial imaging chain to assess the accuracy of the retrieved surface temperatures. By design, the calibration method employed in this application uses ground collected, geolocated water surface temperatures and in-flight blackbody imagery to produce accurate temperature maps of the pond in interest. A sensitivity analysis was implemented within the data reduction technique to produce accurate sensor reaching temperature values using designed equipment and methods for temperature retrieval at the water's surface.

  20. Effects of heating power on divertor in-out asymmetry and scrape-off layer flow in reversed field on Experimental Advanced Superconducting Tokamak

    NASA Astrophysics Data System (ADS)

    Liu, S. C.; Guo, H. Y.; Wang, L.; Wang, H. Q.; Gan, K. F.; Xia, T. Y.; Xu, G. S.; Xu, X. Q.; Liu, Z. X.; Chen, L.; Yan, N.; Zhang, W.; Chen, R.; Shao, L. M.; Ding, S.; Hu, G. H.; Liu, Y. L.; Zhao, N.; Li, Y. L.; Gong, X. Z.; Gao, X.

    2014-12-01

    The dependence of divertor asymmetry and scrape-off layer (SOL) flow on heating power has been investigated in the Experimental Advanced Superconducting Tokamak (EAST). Divertor plasma exhibits an outboard-enhanced in-out asymmetry in heat flux in lower single null configuration for in reversed (ion ? B drift direction toward the upper X-point) field directions. Upper single null exhibits an inboard-favored asymmetry in low heating power condition, while exhibits an outboard-favored asymmetry when increasing the heating power. Double null has the strongest in-out asymmetry in heat flux, favoring the outer divertor. The in-out asymmetry ratios of q t , out / q t , in and P out / P total increase with the power across the separatrix P loss , which is probably induced by the enhanced radial particle transport due to a large pressure gradient. The characteristics of the measured SOL parallel flow under various discharge conditions are consistent with the Pfirsch-Schlüter (PS) flow with the parallel Mach number M ? decreasing with the line averaged density but increasing with P loss , in the same direction as the PS flow. The contributions of both poloidal E × B drift and parallel flow on poloidal particle transport in SOL on EAST are also assessed.

  1. Superconducting multipole corrector magnet

    SciTech Connect

    Kashikhin, Vladimir; /Fermilab

    2004-10-01

    A novel concept of superconducting multipole corrector magnet is discussed. This magnet assembled from 12 identical racetrack type coils and can generate any combination of dipole, quadrupole and sextupole magnetic fields. The coil groups are powered from separate power supplies. In the case of normal dipole, quadrupole and sextupole fields the total field is symmetrical relatively the magnet median plane and there are only five powered separately coil groups. This type multipole corrector magnet was proposed for BTeV, Fermilab project and has following advantages: universal configuration, simple manufacturing and high mechanical stability. The results of magnetic design including the field quality and magnetic forces in comparison with known shell type superconducting correctors are presented.

  2. Stirling cycle solar cooling system

    Microsoft Academic Search

    R. I. Pedroso

    1978-01-01

    The Stirling cycle engine is considered for application to solar powered cooling systems. Two approaches are possible. First, the use of a Stirling engine transmitting mechanical power to any type of cooling unit, and the integral design of a Stirling engine and cooling system. The first approach offers more flexibility in the design of the engine and allows for a

  3. New developments in cooling towers

    Microsoft Academic Search

    Bartz

    1994-01-01

    This article examines developments in power plant cooling systems which include advanced evaporative and dry cooling technologies. Potentials are seen for fabric structures. Developments in cooling tower technology have quietly gained momentum in recent years. Now more choices stand ready to answer just about every need in the power generation industry. As an example, one of the most active areas

  4. Reluctance machines incorporating high temperature superconducting materials on the rotor

    NASA Astrophysics Data System (ADS)

    Rodrigues, A. L.; Pires, A. J.

    2010-01-01

    The computer modelling of reluctance machines with rotors containing both iron and high temperature superconducting (HTS) materials, using the finite element method (FEM), is presented in this paper. The modelling permits to obtain the field and stator current distribution from where reluctance torque is evaluated. Different solutions are analyzed and experimental results on a 2 kW reluctance motor using HTS materials on the rotor and cooled by liquid nitrogen, show a significant increase in the torque values, when compared with that of a correspondent conventional machine. Pre-magnetization of these rotors by field cooling is explained and this process gives a mechanical output power undoubtedly better than that of a conventional reluctance machine.

  5. High temperature superconducting current leads for fusion magnet systems

    NASA Astrophysics Data System (ADS)

    Wu, J. L.; Dederer, J. T.; Singh, S. K.; Hull, J. R.

    Superconducting magnets for fusion applications typically have very high operating currents. These currents are transmitted from the room temperature power supplies to the low temperature superconducting coils by way of helium-vapor-cooled current leads. Because of the high current magnitude and the resistive characteristics associated with the normal metallic lead conductors, a substantial amount of power is dissipated in the lead. To maintain a stable operation, a high rate of helium vapor flow, generated by the boil-off of liquid helium, is required to cool the lead conductors. This helium boil-off substantially increases both the installation capacity and the operating cost of the helium refrigerator/liquefier. The boil-off of liquid helium can be significantly reduced by employing ceramic high temperature superconductors, such as Y-Ba-Cu-O, in the low temperature part of the lead conductor structure. This concept utilizes the superconducting, as well as the low thermal conductivity properties of the superconductor materials in eliminating power dissipation in part of the current lead and in inhibiting heat conduction into the liquid helium pool, resulting in reduced helium boil-off. This design concept has been conclusively demonstrated by a 2-kA current lead test model using Y-Ba-Cu-O (123) material which, although not optimized in design, has significantly reduced the rate of helium boil-off in comparison to optimized conventional leads. There appear to be no major technological barriers for scaling up this design to higher current levels for applications in fusion magnet systems or in fusion related testing activities. The theoretical basis of the current lead concept, as well as the important design and technology issues are addressed. The potential cost saving derived from employing these leads in fusion magnets is also discussed. In addition, a design concept for a 10-kA lead is presented.

  6. Enormous disc of cool gas surrounding the nearby powerful radio galaxy NGC612 (PKS0131-36)

    NASA Astrophysics Data System (ADS)

    Emonts, B. H. C.; Morganti, R.; Oosterloo, T. A.; Holt, J.; Tadhunter, C. N.; van der Hulst, J. M.; Ojha, R.; Sadler, E. M.

    2008-06-01

    We present the detection of an enormous disc of cool neutral hydrogen (HI) gas surrounding the S0 galaxy NGC612, which hosts one of the nearest powerful radio sources (PKS0131-36). Using the Australia Telescope Compact Array, we detect MHI = 1.8 × 109Msolar of HI emission-line gas that is distributed in a 140-kpc wide disc-like structure along the optical disc and dust lane of NGC612. The bulk of the gas in the disc appears to be settled in regular rotation with a total velocity range of 850kms-1, although asymmetries in this disc indicate that perturbations are being exerted on part of the gas, possibly by a number of nearby companions. The HI disc in NGC612 suggests that the total mass enclosed by the system is Menc ~ 2.9 × 1012 sin-2 iMsolar, implying that this early-type galaxy contains a massive dark matter halo. We also discuss an earlier study by Holt et al. that revealed the presence of a prominent young stellar population at various locations throughout the disc of NGC612, indicating that this is a rare example of an extended radio source that is hosted by a galaxy with a large-scale star-forming disc. In addition, we map a faint HI bridge along a distance of 400kpc in between NGC612 and the gas-rich (MHI = 8.9 × 109Msolar) barred galaxy NGC619, indicating that likely an interaction between both systems occurred. From the unusual amounts of HI gas and young stars in this early-type galaxy, in combination with the detection of a faint optical shell and the system's high infrared luminosity, we argue that either ongoing or past galaxy interactions or a major merger event are a likely mechanism for the triggering of the radio source in NGC612. This paper is part of an ongoing study to map the large-scale neutral hydrogen properties of nearby radio galaxies and it presents the first example of large-scale HI detected around a powerful Fanaroff-Riley type II (FR-II) radio galaxy. The HI properties of the FR-II radio galaxy NGC612 are very similar to those found for low-power compact radio sources, but different from those of extended Fanaroff-Riley type I (FR-I) sources.

  7. Selective analysis of power plant operation on the Hudson River with emphasis on the Bowline Point Generating Station. Volume 2. [Multiple impact of power plant once-through cooling systems on fish populations

    Microsoft Academic Search

    L. W. Barnthouse; J. B. Cannon; S. G. Christensen

    1977-01-01

    Because of the location of the Bowline, Roseton, and Indian Point power generating facilities in the low-salinity zone of the Hudson estuary, operation of these plants with the present once-through cooling systems will adversely influence the fish populations that use the area for spawning and initial periods of growth and development. Recruitment rates and standing crops of several fish species

  8. Controlling superconductivity

    NASA Astrophysics Data System (ADS)

    2011-08-01

    The use of intense ultrafast terahertz pulses to gate superconductivity not only provides insights into charge transport in such materials but may also lead to new forms of data switching, explains Andrea Cavalleri.

  9. The low-power low-pressure flow resonance in a natural circulation cooled boiling water reactor

    Microsoft Academic Search

    T. H. J. J. van der Hagen; A. J. C. Stekelenburg

    1997-01-01

    The last few years the possibility of flow resonances during the start-up phase of natural circulation cooled boiling water reactors (BWRs) has been put forward by several authors. The present paper reports on actual oscillations observed at the Dodewaard reactor, the world's only operating BWR cooled by natural circulation. In addition, results of a parameter study performed by means of

  10. Superconductivity: Phenomenology

    SciTech Connect

    Falicov, L.M.

    1988-08-01

    This document discusses first the following topics: (a) The superconducting transition temperature; (b) Zero resistivity; (c) The Meissner effect; (d) The isotope effect; (e) Microwave and optical properties; and (f) The superconducting energy gap. Part II of this document investigates the Ginzburg-Landau equations by discussing: (a) The coherence length; (b) The penetration depth; (c) Flux quantization; (d) Magnetic-field dependence of the energy gap; (e) Quantum interference phenomena; and (f) The Josephson effect.

  11. Semiannual report for the period April 1-September 30, 1979 of work on: (1) Superconducting power transmission development; (2) Cable insulation development. Power Transmission Project Technical Note No. 99

    SciTech Connect

    Not Available

    1980-01-15

    The objective of the program is to develop an underground superconducting power transmission system which is economical and technically attractive to the utility industry. The system would be capable of carrying very large blocks of electric power, thus enabling it to supplant overhead lines in urban and suburban areas and regions of natural beauty. The program consisted initially of work in the laboratory to develop suitable materials, cryostats, and cable concepts. The materials work covers the development and testing of suitable superconductors and dielectric insulation. The laboratory work has now been extended to an outside test facility which represents an intermediate step between the laboratory scale and a full-scale system. The facility will allow cables several hundred feet long to be tested under realistic conditions. In addition, the refrigerator has been designed for optimum service for utility applications.

  12. COOL-IT: A HEAT EXCHANGER SYSTEM TO PROVIDE GASEOUS HELIUM AT INTERMEDIATE TEMPERATURES FOR SRF LINAC

    SciTech Connect

    Pattalwar, S. M.; Bate, R. [Accelerator Science and Technology Centre, STFC Daresbury Laboratory, Warrington, WA4 4AD (UK) (United Kingdom)

    2010-04-09

    ALICE, a prototype accelerator developed at the Daresbury laboratory UK, has successfully demonstrated the energy-recovery technique by circulating the electron beam to more than 20 MeV. At the heart of ALICE is a superconducting linac operating at 2 K. At high average-current operation the performance of Superconducting RF (SRF) cavities suffer from instabilities due to the generation of higher-order modes (HOM) as well as microphonics. HOMs are extracted out of the cavities using HOM absorbers operating at 80 K. This, however, increases the demand for cooling power at intermediate temperatures, i.e. at 80 K and 5 K, by more than an order of magnitude.In order to provide this extra cooling capacity with gaseous helium a new cryogenic system, 'COOL-IT,'(System for cooling to intermediate temperatures) is being developed. It will provide two streams of helium gases at 80 K and 5 K. COOL-IT uses a set of heat exchangers cooled by liquid helium and liquid nitrogen to generate two cold streams. It will be integrated into the existing cryo-system for ALICE for automatic operation. This paper describes the COOL-IT system in detail.

  13. Coexistence of Legionella pneumophila Bacteria and Free-Living Amoebae in Lakes Serving as a Cooling System of a Power Plant.

    PubMed

    Zbikowska, El?bieta; Kletkiewicz, Hanna; Walczak, Maciej; Burkowska, Aleksandra

    2014-01-01

    The study was aimed at determining whether potentially pathogenic free-living amoebae (FLA) and Legionella pneumophila can be found in lakes serving as a natural cooling system of a power plant. Water samples were collected from five lakes forming the cooling system of the power plants P?tnów and Konin (Poland). The numbers of investigated organisms were determined with the use of a very sensitive molecular method-fluorescence in situ hybridization (FISH). The result of the present study shows that thermally altered aquatic environments provide perfect conditions for the growth of L. pneumophila and amoebae. The bacteria were identified in the biofilm throughout the entire research period and in the subsurface water layer in July and August. Hartmanella sp. and/or Naegleria fowleri were identified in the biofilm throughout the entire research period. PMID:25132694

  14. Radiation Heating Analysis for Superconducting Undulator

    NASA Astrophysics Data System (ADS)

    Boon, Laura; Harkay, Katherine; Ivanyushenkov, Yury; Shiroyanagi, Yuko

    2014-03-01

    In January 2013 the Advanced Photon Source commissioned a Superconducting Undulator (SCU). The superconducting magnet is thermally isolated from the beam vacuum chamber, which absorbs the beam-induced heating. The cryo-coolers cooling the vacuum chamber can handle 40 W of heating. Throughout the SCU design process calculations were made to determine the radiation heating from an on-axis and off-axis electron beam. Simulation results show that when the electron beam is vertically off-axis radiation heating increases from the on-axis heating of less than 1 W. During user operation beam-position-limiting detectors (BPLD) are used to limit beam motion and keep the radiation heating below 25 W. During machine studies when the BPLD is not armed other measures must be taken to protect the SCU. Presented in this talk will be the comparison between analytical calculations and measured temperature rise on the installed SCU. The measured temperatures have been converted to a power using a finite element model.

  15. Magnetic cooling by an adiabatic spin reorientation

    Microsoft Academic Search

    T. Morishita; K. Tsushima

    1984-01-01

    A new method of magnetic cooling is proposed by using an adiabatic entropy change associated with a spin reorientation transition. This is available for a magnetic refrigerator operating under a weaker magnetic field than an ordinary method using a superconducting magnet to cool a paramagnetic crystal. The single crystal and sintered samples of ErCrOâ were adopted as a prototype material.

  16. Improving Vortex Generators to Enhance the Performance of Air-Cooled Condensers in a Geothermal Power Plant

    SciTech Connect

    Manohar S. Sohal

    2005-09-01

    This report summarizes work at the Idaho National Laboratory to develop strategies to enhance air-side heat transfer in geothermal air-cooled condensers such that it should not significantly increase pressure drop and parasitic fan pumping power. The work was sponsored by the U.S. Department of Energy, NEDO (New Energy and Industrial Technology Development Organization) of Japan, Yokohama National University, and the Indian Institute of Technology, Kanpur, India. A combined experimental and numerical investigation was performed to investigate heat transfer enhancement techniques that may be applicable to largescale air-cooled condensers such as those used in geothermal power applications. A transient heat transfer visualization and measurement technique was employed in order to obtain detailed distributions of local heat transfer coefficients on model fin surfaces. Pressure drop measurements were obtained for a variety of tube and winglet configurations using a single-channel flow apparatus that included four tube rows in a staggered array. Heat transfer and pressure drop measurements were also acquired in a separate multiple-tube row apparatus in the Single Blow Test Facility. In addition, a numerical modeling technique was developed to predict local and average heat transfer for these low-Reynolds number flows, with and without winglets. Representative experimental and numerical results were obtained that reveal quantitative details of local finsurface heat transfer in the vicinity of a circular tube with a single delta winglet pair downstream of the cylinder. Heat transfer and pressure-drop results were obtained for flow Reynolds numbers based on channel height and mean flow velocity ranging from 700 to 6500. The winglets were of triangular (delta) shape with a 1:2 or 1:3 height/length aspect ratio and a height equal to 90% of the channel height. Overall mean fin-surface heat transfer results indicate a significant level of heat transfer enhancement (in terms of Colburn j-factor) associated with deployment of the winglets with circular as well as oval tubes. In general, toe-in (common flow up) type winglets appear to have better performance than the toe-out (common flow down) type winglets. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided. During the course of their independent research, all of the researchers have established that about 10 to 30% enhancement in Colburn j-factor is expected. However, actual increase in heat transfer rate from a heat exchanger employing finned tubes with winglets may be smaller, perhaps on the order of 2 to 5%. It is also concluded that for any specific application, more full-size experimentation is needed to optimize the winglet design for a specific heat exchanger application. If in place of a circular tube, an oval tube can be economically used in a bundle, it is expected that the pressure drop across the tube bundle with the application of vortex generators (winglets) will be similar to that in a conventional circular tube bundle. It is hoped that the results of this research will demonstrate the benefits of applying vortex generators (winglets) on the fins to improve the heat transfer from the air-side of the tube bundle.

  17. Status of the plasma generator of the superconducting proton linac.

    PubMed

    Kronberger, M; Faircloth, D; Lettry, J; Paoluzzi, M; Pereira, H; Sanchez Arias, J; Schmitzer, C; Scrivens, R

    2012-02-01

    In the framework of the superconducting proton linac (SPL) study at CERN, a new non-cesiated H(-) plasma generator driven by an external 2 MHz RF antenna has been developed and successfully operated at repetition rates of 50 Hz, pulse lengths of up to 3 ms, and average RF powers of up to 3 kW. The coupling efficiency of RF power into the plasma was determined by the cooling water temperatures and the analysis of the RF forward and reflected power and the antenna current and amounts to 50%-60%. The plasma resistance increases between 10 kW and 40 kW RF power from about 0.45 ? to 0.65 ?. Measurements of RF power dissipated in the ferrites and the magnets on a test bench show a 5-fold decrease of the power losses for the magnets when they are contained in a Cu box, thus validating the strategy of shielding the magnets with a high electrical conductivity material. An air cooling system was installed in the SPL plasma generator to control the temperatures of the ferrites despite hysteresis losses of several Watts. PMID:22380212

  18. Design considerations of a pair of power leads for fast-cycling superconducting accelerator magnets operating at 2 Tesla and 100 kA

    SciTech Connect

    Huang, Yuenian; Hays, Steven; Piekarz, Henryk; de Rijk, Gijsbert; Rossi, L.; /Fermilab /CERN

    2007-08-01

    Recently proposed injector accelerator, Low Energy Ring (LER) for the LHC and fast cycling accelerators for the proton drivers (SF-SPS at CERN and DSF-MR at Fermilab) require that a new magnet technology be developed. In support of this accelerator program, a pair of power leads needs to be developed to close the loop between the power supply and accelerator system. The magnet proposed to be used will be a modified transmission line magnet technology that would allow for accelerator quality magnetic field sweep of 2 T/s. The transmission line conductor will be using HTS technology and cooled with supercritical helium at 5 K. The power leads consist of two sections; upper one is a copper and lower section will be using HTS tapes. The accelerator magnet will be ramped to 100 kA in a second and almost immediately ramped down to zero in one second. This paper outlines the design considerations for the power leads to meet the operational requirements for the accelerator system. The power leads thermal analysis during the magnet powering cycle will be included.

  19. Noise Temperature and Absorbed LO Power Measurement Methods for NbN Phonon-Cooled Hot Electron Bolometric Mixers at Terahertz Frequencies

    Microsoft Academic Search

    Harald F. Merkel; Pavel A. Yagoubov; Matthias Kroug; Pourya Khosropanah; Erik L. Kollberg; Gregory N. Gol'tsman; Eugene M. Gershenzon

    1998-01-01

    In this paper the absorbed LO power requirements and the noise performance of NbN based phonon-cooled hot electron bolometric (HEB) quasioptical mixers are investigated for RF frequencies in the 0.55-1.1 range The minimal measured DSB noise temperatures are about 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz and 1250 K at 1.1 THz.

  20. MR-guided laser-induced thermotherapy with a cooled power laser system: a case report of a patient with a recurrent carcinoid metastasis in the breast

    Microsoft Academic Search

    Thomas J. Vogl; Martin G. Mack; Ralf Straub; Katrin Eichler; Stephan Zangos; Kerstin Engelmann; Kathrin Hochmuth; Sabine Ballenberger; Volkmar Jacobi; Thomas Diebold

    2002-01-01

    We report a case of a 52-year-old woman with a palpable recurrent metastasis of a neuroendocrine carcinoma to the upper outer quadrant of the right breast. For the treatment of this lesion, MR-guided laser-induced thermotherapy was performed with a cooled power laser system (Nd:YAG-Laser). An open 0.2-T MR unit was used for the monitoring of the laser energy delivery to

  1. A "permanent" high-temperature superconducting magnet operated in thermal communication with a mass of solid nitrogen

    E-print Network

    Haid, Benjamin J. (Benjamin John Jerome), 1974-

    2001-01-01

    This thesis explores a new design for a portable "permanent" superconducting magnet system. The design is an alternative to permanent low-temperature superconducting (LTS) magnet systems where the magnet is cooled by a ...

  2. Ripple current loss measurement with DC bias condition for high temperature superconducting power cable using calorimetry method

    NASA Astrophysics Data System (ADS)

    Kim, D. W.; Kim, J. G.; Kim, A. R.; Park, M.; Yu, I. K.; Sim, K. D.; Kim, S. H.; Lee, S. J.; Cho, J. W.; Won, Y. J.

    2010-11-01

    The authors calculated the loss of the High Temperature Superconducting (HTS) model cable using Norris ellipse formula, and measured the loss of the model cable experimentally. Two kinds of measuring method are used. One is the electrical method, and the other is the calorimetric method. The electrical method can be used only in AC condition. But the calorimetric method can be used in both AC and DC bias conditions. In order to propose an effective measuring approach for Ripple Dependent Loss (RDL) under DC bias condition using the calorimetric method, Bismuth Strontium Calcium Copper Oxide (BSCCO) wires were used for the HTS model cable, and the SUS tapes were used as a heating tape to make the same pattern of the temperature profiles as in the electrical method without the transport current. The temperature-loss relations were obtained by the electrical method, and then applied to the calorimetric method by which the RDL under DC bias condition was well estimated.

  3. Monitoring peak power and cooling energy savings of shade trees and white surfaces in the Sacramento Municipal Utility District (SMUD) service area: Project design and preliminary results

    SciTech Connect

    Akbari, H.; Bretz, S.; Hanford, J.; Rosenfeld, A.; Sailor, D.; Taha, H. [Lawrence Berkeley Lab., CA (United States); Bos, W. [Sacramento Municipal Utility District, CA (United States)

    1992-12-01

    Urban areas in warm climates create summer heat islands of daily average intensity of 3--5{degrees}C, adding to discomfort and increasing air-conditioning loads. Two important factors contributing to urban heat islands are reductions in albedo (lower overall city reflectance) and loss of vegetation (less evapotranspiration). Reducing summer heat islands by planting vegetation (shade trees) and increasing surface albedos, saves cooling energy, allows down-sizing of air conditioners, lowers air-conditioning peak demand, and reduces the emission of CO{sub 2} and other pollutants from electric power plants. The focus of this multi-year project, jointly sponsored by SMUD and the California Institute for Energy Efficiency (CIEE), was to measure the direct cooling effects of trees and white surfaces (mainly roofs) in a few buildings in Sacramento. The first-year project was to design the experiment and obtain base case data. We also obtained limited post retrofit data for some sites. This report provides an overview of the project activities during the first year at six sites. The measurement period for some of the sites was limited to September and October, which are transitional cooling months in Sacramento and hence the interpretation of results only apply to this period. In one house, recoating the dark roof with a high-albedo coating rendered air conditioning unnecessary for the month of September (possible savings of up to 10 kWh per day and 2 kW of non-coincidental peak power). Savings of 50% relative to an identical base case bungalow were achieved when a school bungalow`s roof and southeast wall were coated with a high-albedo coating during the same period. Our measured data for the vegetation sites do not indicate conclusive results because shade trees were small and the cooling period was almost over. We need to collect more data over a longer cooling season in order to demonstrate savings conclusively.

  4. Assessment of Non-electric Cooling Alternatives to Reduce the Electric Demand of New York's Power Grid

    Microsoft Academic Search

    Khaled A. Yousef; Ronald B. Slosberg; Mark Eggers; Christopher Reohr

    2003-01-01

    Electric cooling technologies impose significant demand on the utility grid. For instance, the cooling system for a 200,000 square foot building can add over 300 kW of electric load onto the grid during peak summer periods. A typical 600,000-square-foot building has an electric chiller plant that peaks at nearly 1 MW. Natural gas and steam chillers, on the other hand,

  5. Superconducting Memristors

    NASA Astrophysics Data System (ADS)

    Peotta, Sebastiano; Di Ventra, Massimiliano

    2014-09-01

    In his original work, Josephson predicted that a phase-dependent conductance should be present in superconducting tunnel junctions, an effect difficult to detect, mainly because it is hard to single it out from the usual nondissipative Josephson current. We propose a solution for this problem that consists of using different superconducting materials to realize the two junctions of a superconducting interferometer. According to the Ambegaokar-Baratoff relation the two junctions have different conductances if the critical currents are equal, thus the Josephson current can be suppressed by fixing the magnetic flux in the loop at half of a flux quantum without canceling the phase-dependent conductance. Our proposal can be used to study the phase-dependent conductance, an effect present in principle in all superconducting weak links. From the standpoint of nonlinear circuit theory, such a device is in fact an ideal memristor with possible applications to memories and neuromorphic computing in the framework of ultrafast and low-energy-consumption superconducting digital circuits.

  6. Progress on Design and Construction of a MuCool Coupling Solenoid Magnet

    SciTech Connect

    Wang, L.; Liu, Xiao Kun; Xu, FengYu; Li, S.; Pan, Heng; Wu, Hong; Guo, Xinglong; Zheng, ShiXian; Li, Derun; Virostek, Steve; Zisman, Mike; Green, M.A.

    2010-06-28

    The MuCool program undertaken by the US Neutrino Factory and Muon Collider Collaboration is to study the behavior of muon ionization cooling channel components. A single superconducting coupling solenoid magnet is necessary to pursue the research and development work on the performance of high gradient, large size RF cavities immersed in magnetic field, which is one of the main challenges in the practical realization of ionization cooling of muons. The MuCool coupling magnet is to be built using commercial copper based niobium titanium conductors and cooled by two cryo-coolers with each cooling capacity of 1.5 W at 4.2 K. The solenoid magnet will be powered by using a single 300A power supply through a single pair of binary leads that are designed to carry a maximum current of 210A. The magnet is to be passively protected by cold diodes and resistors across sections of the coil and by quench back from the 6061 Al mandrel in order to lower the quench voltage and the hot spot temperature. The magnet is currently under construction. This paper presents the updated design and fabrication progress on the MuCool coupling magnet.

  7. Effect of spray cooling on heat transfer in a two-phase helium flow

    NASA Astrophysics Data System (ADS)

    Perraud, S.; Puech, L.; Thibault, P.; Rousset, B.; Wolf, P. E.

    2013-10-01

    We describe an experimental study of the phenomenon of spray cooling in the case of liquid helium, either normal or superfluid, and its relationship to the heat transfer between an atomized two-phase flow contained in a long pipe, and the pipe walls. This situation is discussed in the context of the cooling of the superconducting magnets of the Large Hadron Collider (LHC). Experiments were conducted in a test loop reproducing the LHC cooling system, in which the vapor velocity and temperature could be varied in a large range. Shear induced atomization results in the generation of a droplet mist which was characterized by optical means. The thickness of the thin liquid film deposited on the walls by the mist was measured using interdigitated capacitors. The cooling power of the mist was measured using thermal probes, and correlated to the local mist density. Analysis of the results shows that superfluidity has only a limited influence on both the film thickness and the mist cooling power. Using a simple model, we show that the phenomenon of spray cooling accounts for the measured non-linearity of the global heat transfer. Finally, we discuss the relevance of our results for cooling the final focus magnets in an upgraded version of the LHC.

  8. VLHC Beam Screen Cooling

    Microsoft Academic Search

    C. Darve; P. Bauer; P. Limon; T. Peterson

    In the framework of the Very Large Hadron Collider (VLHC) R&D studies, vacuum and beam screen issues are being investigated at Fermilab. This report focuses on the cooling system for the VLHC beam screen and its integration into the VLHC cryo-system. Beam screen cooling is a key issue in the VLHC, due to the large synchrotron radiation (SR) power generated

  9. VLHC Thermal Shield Cooling

    Microsoft Academic Search

    C. Darve; P. Bauer; T. Nicol; T. Peterson

    The Very Large Hadron Collider (VLHC) - stage 2 cooling system has been optimized regarding the ability to minimize the total refrigeration power. The stage 2 VLHC synchrotron radiation dictates a high optimal beam screen temperature. LHC dipole cryostat thermal model results provide data to characterize the behavior of the stage 2 VLHC cooling system. In the cryogenic concept pursued

  10. Dry cooling tower with water augmentation

    Microsoft Academic Search

    R. G. Ireland; V. N. Tramontini

    1981-01-01

    An air cooling tower system is disclosed for condensing exhaust steam in power plants, that has water cooling augmentation to maintain the plant cooling capacity during high atmospheric temperature periods. The cooling tower includes a plurality of banks of brazed aluminum plate and fin type heat exchangers arranged in inverted ''v'' shaped sets. These heat exchangers cool ammonia used as

  11. ASTROMAG coil cooling study

    NASA Technical Reports Server (NTRS)

    Maytal, Ben-Zion; Vansciver, Steven W.

    1990-01-01

    ASTROMAG is a planned particle astrophysics magnetic facility. Basically it is a large magnetic spectrometer outside the Earth's atmosphere for an extended period of time in orbit on a space station. A definition team summarized its scientific objectives assumably related to fundamental questions of astrophysics, cosmology, and elementary particle physics. Since magnetic induction of about 7 Tesla is desired, it is planned to be a superconducting magnet cooled to liquid helium 2 temperatures. The general structure of ASTROMAG is based on: (1) two superconducting magnetic coils, (2) dewar of liquid helium 2 to provide cooling capability for the magnets; (3) instrumentation, matter-anti matter spectrometer (MAS) and cosmic ray isotope spectrometer (CRIS); and (4) interfaces to the shuttle and space station. Many configurations of the superconducting magnets and the dewar were proposed and evaluated, since those are the heart of the ASTROMAG. Baseline of the magnet configuration and cryostat as presented in the phase A study and the one kept in mind while doing the present study are presented. ASTROMAG's development schedule reflects the plan of launching to the space station in 1995.

  12. Scaling of divertor power footprint width in RF-heated type-III ELMy H-mode on the EAST superconducting tokamak

    NASA Astrophysics Data System (ADS)

    Wang, L.; Guo, H. Y.; Xu, G. S.; Liu, S. C.; Gan, K. F.; Wang, H. Q.; Gong, X. Z.; Liang, Y.; Zou, X. L.; Hu, J. S.; Chen, L.; Xu, J. C.; Liu, J. B.; Yan, N.; Zhang, W.; Chen, R.; Shao, L. M.; Ding, S.; Hu, G. H.; Feng, W.; Zhao, N.; Xiang, L. Y.; Liu, Y. L.; Li, Y. L.; Sang, C. F.; Sun, J. Z.; Wang, D. Z.; Ding, H. B.; Luo, G. N.; Chen, J. L.; Gao, X.; Hu, L. Q.; Wan, B. N.; Li, J.; the EAST Team

    2014-11-01

    Dedicated experiments for the scaling of divertor power footprint width have been performed in the ITER-relevant radio-frequency (RF)-heated H-mode scheme under the lower single null, double null and upper single null divertor configurations in the Experimental Advanced Superconducting Tokamak (EAST) under lithium wall coating conditioning. A strong inverse scaling of the edge localized mode (ELM)-averaged power fall-off width with the plasma current (equivalently the poloidal field) has been demonstrated for the attached type-III ELMy H-mode as ?q \\propto Ip-1.05 by various heat flux diagnostics including the divertor Langmuir probes (LPs), infra-red (IR) thermograph and reciprocating LPs on the low-field side. The IR camera and divertor LP measurements show that ?q,IR ? {?q,div{-LPs}}/{1.3}=1.15Bp,omp-1.25 , in good agreement with the multi-machine scaling trend during the inter-ELM phase between type-I ELMs or ELM-free enhanced D? (EDA). H-mode. However, the magnitude is nearly doubled, which may be attributed to the different operation scenarios or heating schemes in EAST, i.e., dominated by electron heating. It is also shown that the type-III ELMs only broaden the power fall-off width slightly, and the ELM-averaged width is representative for the inter-ELM period. Furthermore, the inverse Ip (Bp) scaling appears to be independent of the divertor configurations in EAST. The divertor power footprint integral width, fall-off width and dissipation width derived from EAST IR camera measurements follow the relation, ?int ? ?q + 1.64S, yielding ?_intEAST =(1.39+/- 0.03)?qEAST +(0.97+/- 0.35) mm . Detailed analysis of these three characteristic widths was carried out to shed more light on their extrapolation to ITER.

  13. Superconductive articles

    SciTech Connect

    Wu, X.D.; Muenchausen, R.E.

    1991-12-31

    An article of manufacture including a substrate, a patterned interlayer of magnesium oxide, barium-titanium oxide or barium-zirconium oxide, the patterned interlayer material overcoated with a secondary interlayer material of yttria-stabilized zirconia or magnesium-aluminum oxide, upon the surface of the substrate whereby an intermediate article with an exposed surface of both the overcoated patterned interlayer and the substrate is formed, a coating of a buffer layer selected from the group consisting of oxides of Ce, Y, Cm, Dy, Er, Eu, Fe, Gd, Ho, In, La, Mn, Lu, Nd, Pr, Pu, Sm, Tb, Tl, Tm, Y, and Yb over the entire exposed surface of the intermediate article, and, a ceramic superconductive material layer as an overcoat upon the buffer layer whereby the ceramic superconductive material situated directly above the substrate has a crystal structure substantially different than the ceramic superconductive material situated above the overcoated patterned interlayer.

  14. Marketing Cool Storage Technology 

    E-print Network

    McCannon, L.

    1987-01-01

    construction costs, more stringent regulations, and increasing environmental constraints regarding development of new generating facilities. As the viability of cool storage has been substantiated by research conducted by Electric Power Research Institute...

  15. Boiling helium heat transfer characteristics in narrow cooling channel

    Microsoft Academic Search

    M. Nishi; T. Ando; T. Hiyama; T. Kato; S. Shimamoto

    1983-01-01

    For design of a stable superconducting magnet with pool cooling method, the size of the cooling channel is one of the important factors to determine its overall current density. The authors measured the steady state boiling helium heat transfer characteristics in a 600 mm long vertical cooling channel. The result shows that heat transfer characteristics in film boiling region do

  16. Fast superconducting magnetic field switch

    DOEpatents

    Goren, Y.; Mahale, N.K.

    1996-08-06

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles. 6 figs.

  17. Fast superconducting magnetic field switch

    DOEpatents

    Goren, Yehuda (Mountain View, CA); Mahale, Narayan K. (The Woodlands, TX)

    1996-01-01

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

  18. Feasibility study on superconducting fault current limiting transformer (SFCLT)

    Microsoft Academic Search

    N. Hayakawa; S. Chigusa; N. Kashima; S. Nagaya; H. Okubo

    2000-01-01

    This paper proposes a “superconducting fault current limiting transformer (SFCLT)” with functions of both superconducting fault current limiters and superconducting transformers. Concepts of the SFCLT are as follows: (1) When a fault occurs in a power system, the SFCLT acts as a fault current limiter with limiting impedance due to quench of the SFCLT windings, which improves the transient stability

  19. Development of a 4.5 K Pulse Tube Cryocooler for Superconducting Electronics

    NASA Astrophysics Data System (ADS)

    Nast, Ted; Olson, Jeff; Champagne, Patrick; Mix, Jack; Evtimov, Bobby; Roth, Eric; Collaco, Andre

    2008-03-01

    Lockheed Martin's (LM) Advanced Technology Center (ATC) has developed a four stage pulse tube cryocooler (stirling-type pulse tube system) to provide cooling at 4.5 K for superconducting digital electronics communications programs. These programs utilize superconducting niobium integrated circuits [1, 2]. A prior ATC 4 stage unit has provided cooling to 3.8 K. [3] The relatively high cooling loads for the present program led us to a new design which improves the 4.5 K power efficiency over prior systems. This design includes a unique pulse tube approach using both He-3 and He-4 working gas in two compression spaces. The compressor utilizes our standard moving magnet linear motor, clearance seal and flexure bearing system. The system is compact, lightweight and reliable and utilizes our aerospace cooler technology to provide unlimited lifetime. The unit is a proof of concept, but the construction is at an engineering model level. Follow on activities for improvements of performance and more compact packaging and future production for ground based communication systems is anticipated. This paper presents the experimental results at various cooling conditions. Primary results are shown for HYPRES cooling requirements and data is also included at lower cooling loads that may be required for future space missions. The system provides a maximum of 42 mW @ 4.5 K and a no load temperature of 3 K. The majority of this work was subcontracted by HYPRES and funded by the Army and Navy. A small part of this effort to obtain data at lower cooling loads (1-10 mW @ 4.5 K) was funded by LM internal funds.

  20. Superconducting magnets

    SciTech Connect

    Willen, E.

    1996-12-31

    Superconducting dipole magnets for high energy colliders are discussed. As an example, the magnets recently built for the Relativistic Heavy Ion Collider at Brookhaven are reviewed. Their technical performance and the cost for the industry-built production dipoles are given. The cost data is generalized in order to extrapolate the cost of magnets for a new machine.

  1. Superconducting magnets

    SciTech Connect

    Not Available

    1994-08-01

    This report discusses the following topics on superconducting magnets: D19B and -C: The next steps for a record-setting magnet; D20: The push beyond 10 T: Beyond D20: Speculations on the 16-T regime; other advanced magnets for accelerators; spinoff applications; APC materials development; cable and cabling-machine development; and high-{Tc} superconductor at low temperature.

  2. Electronic cooling in graphene.

    PubMed

    Bistritzer, R; MacDonald, A H

    2009-05-22

    Energy transfer to acoustic phonons is the dominant low-temperature cooling channel of electrons in a crystal. For cold neutral graphene we find that the weak cooling power of its acoustic modes relative to their heat capacity leads to a power-law decay of the electronic temperature when far from equilibrium. For heavily doped graphene a high electronic temperature is shown to initially decrease linearly with time at a rate proportional to n;{3/2} with n being the electronic density. The temperature at which cooling via optical phonon emission begins to dominate depends on graphene carrier density. PMID:19519053

  3. Fabrication of double mesa structures by E-beam lithography from high temperature superconducting Bi2Sr2CaCu2O8+? (Bi2212) for powerful terahertz emission

    Microsoft Academic Search

    Y. Demirhan; F. Turkoglu; H. Koseoglu; H. Saglam; M. Minematsu; H. Araki; N. Miyakawa; L. Ozyuzer

    2011-01-01

    We work on a frequency tunable solid state device to meet the needs of continuous, coherent, powerful terahertz emission sources that fill practically important terahertz gap. High temperature superconducting (HTS) coherently oscillating Josephson junctions in Bi2Sr2CaCu2O8+? (Bi2212) crystal make this approach very promising. Since doping dependence of Bi2212 is an important parameter, Bi2212 crystals are annealed in vacuum or purified

  4. First Russian long length HTS power cable

    NASA Astrophysics Data System (ADS)

    Volkov, Eduard P.; Vysotsky, Vitaly S.; Firsov, Valery P.

    2012-11-01

    The Russian R&D Program for superconducting power devices is underway, supported both by government and electric power companies. In this program R&D on HTS power cables is considered as most advanced and close to commercialization. In the framework of the program, several, heavily instrumented, 5 m cables have been tested following by the 30 m - 3 phase experimental power cable development and testing in 2008-2009. The latest achievement is development and testing of the first long length 3 × 200 m power cable with rating 1.5/2 kA-20 kV. In parallel with just the cable development the innovative cryogenic system has been developed as well for the cable cooling. The system is using neon as working substance and radial turbo-machines in refrigerator. Cooling power is up to ?8 kW at 65 K, inter-maintenance time ?30,000 h. The cryogenic pump with superconducting motor can be used to provide subcooled liquid nitrogen flow ?0.1-1.5 kg/s at 0.1-2.5 MPa pressure. After extensive tests at special test facility, HTS power cable and cryogenic system are planning to be installed at some substation in Moscow utility grid. In this review some details about Russian HTS power application program, 200 m cable and cryogenic system designs and tests results are presented.

  5. Cooling wall

    Microsoft Academic Search

    Nosenko

    1995-01-01

    Protecting the shells of blast furnaces is being resolved by installing cast iron cooling plates. The cooling plates become non-operational in three to five years. The problem is that defects occur in manufacturing the cooling plates. With increased volume and intensity of work placed on blast furnaces, heat on the cast iron cooling plates reduces their reliability that limits the

  6. Corium retention for high power reactors by an in-vessel core catcher in combination with External Reactor Vessel Cooling

    Microsoft Academic Search

    J. L. Rempe; D. L. Knudson; K. G. Condie; K. Y. Suh; F.-B. Cheung; S.-B. Kim

    2004-01-01

    If there were inadequate cooling during a reactor accident, a significant amount of core material could become molten and relocate to the lower head of the reactor vessel, as happened in the Three Mile Island Unit 2 (TMI-2) accident. If it is possible to ensure that the vessel lower head remains intact so that relocated core materials are retained within

  7. Is cooling still cool?

    PubMed

    Subramaniam, Ashwin; Tiruvoipati, Ravindranath; Botha, John

    2015-03-01

    Therapeutic hypothermia (TH), where patients are cooled to between 32°C and 36°C for a period of 12-24 hours and then gradually rewarmed, may reduce the risk of ischemic injury to cerebral tissue following a period of insufficient blood flow. This strategy of TH could improve mortality and neurological function in patients who have experienced out-of-hospital cardiac arrest (OOHCA). The necessity of TH in OOHCA was challenged in late 2013 by a fascinating and potentially practice changing publication, which found that targeting a temperature of 36°C had similar outcomes to cooling patients to 33°C. This article reviews the current literature and summarizes the uncertainties and questions raised when considering cooling of patients at risk of hypoxic brain injury. Irrespective of whether TH or targeted temperature management is deployed in patients at risk of hypoxic brain injury, it would seem that avoiding hyperpyrexia is important and that a more rigorous approach to neurological evaluation is mandated. PMID:25423577

  8. Radiation dose assessment for the biota of terrestrial ecosystems in the shoreline zone of the Chernobyl nuclear power plant cooling pond.

    PubMed

    Oskolkov, Boris Ya; Bondarkov, Mikhail D; Gaschak, Sergey P; Maksimenko, Andrey M; Hinton, Thomas G; Coughlin, Daniel; Jannik, G Timothy; Farfán, Eduardo B

    2011-10-01

    Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. This paper addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from 90Sr and 137Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to draw down naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature. PMID:21878760

  9. RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND

    SciTech Connect

    Farfan, E.; Jannik, T.

    2011-10-01

    Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.

  10. High temperature superconducting fault current limiter

    DOEpatents

    Hull, J.R.

    1997-02-04

    A fault current limiter for an electrical circuit is disclosed. The fault current limiter includes a high temperature superconductor in the electrical circuit. The high temperature superconductor is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter. 15 figs.

  11. Simulations of multipacting in the cathode stalk and FPC of 112 MHz superconducting electron gun

    SciTech Connect

    Xin T.; Ben-Zvi, I.; Belomestnykh, S.; Chang, X.; Rao, T.; Skaritka, J.; Wu, Q.; Wang, E.; Liang, X.

    2012-05-20

    A 112 MHz superconducting quarter-wave resonator electron gun will be used as the injector of the Coherent Electron Cooling (CEC) proof-of-principle experiment at BNL. Furthermore, this electron gun can be used for testing of the performance of various high quantum efficiency photocathodes. In a previous paper, we presented the design of the cathode stalks and a Fundamental Power Coupler (FPC). In this paper we present updated designs of the cathode stalk and FPC. Multipacting in the cathode stalk and FPC was simulated using three different codes. All simulation results show no serious multipacting in the cathode stalk and FPC.

  12. DESIGN, CONSTRUCTION, AND STATUS OF ALL NIOBIUM SUPERCONDUCTING PHOTOINJECTOR AT BNL.

    SciTech Connect

    SRINIVASAN-RAO,T.BEN-ZVI,I.BURRILL,A.CITVER,G.ET AL.

    2004-05-12

    We present here the design and construction of an all niobium superconducting RF injector to generate high average current, high brightness electron beam. A 1/2 cell superconducting cavity has been designed, built, and tested. A cryostat has been built to cool the cavity to {approx}2 K. The RF system can deliver up to 500 W at 1.3 GHz to the cavity. A mode-locked Nd:YVO{sub 4} laser, operating at 266 nm with 0.15 W average power, phase locked to the RF, will irradiate a laser cleaned Nb surface at the back wall of the cavity. Description of critical components and their status are presented in the paper. Based on DC measurements, QE of up to 10{sup 4} can be expected from such cavity.

  13. Cryo-delivery Systems for the Co-transmission of Chemical and Electrical Power

    NASA Astrophysics Data System (ADS)

    Grant, Paul M.

    2006-04-01

    We present a novel concept for the simultaneous transport of chemical power in the form of natural gas or hydrogen in a cryogenic state along with the simultaneous transmission of electrical power over via superconductivity. This concept could impact future efforts to tap and deliver methane from distant geographic resources over conventional pipelines with part of the chemical potential energy converted directly to electricity at the wellhead and the remaining gas cooled cryogenically to increase volumetric density and provide the necessary support of a superconducting cable housed within the same packaging. As the fossil reserve becomes depleted, nuclear power plants would be constructed at the former remote wellhead sites to co-generate electricity and cryocooled hydrogen, the latter replacing natural gas and also serving to operate the already installed superconducting electrical service line.

  14. Superconductivity: will its potential be realized

    SciTech Connect

    Lerner, E.J.

    1980-04-01

    The article surveys possible applications of superconductivity and the question of how rapidly or whether this potential will be realized. Attention is given to applications such as magnetic levitation trains, Josephson junction computers, new means of cancer detection, and water purification. Also discussed are the use of superconducting magnets to produce the high fields needed for nuclear fusion plants and for magnetohydrodynamic generators. Further, experiments under way on superconducting power lines for virtually lossless transmission of electric power are examined. It is concluded that the main obstacle to implementation of such applications is the reluctance of American business and government to invest in further research.

  15. Power-Law Fading of the Frustration Effect in a Periodic Rectangular Superconducting Network with Increasing Aspect Ratio 

    E-print Network

    Hu, Chia-Ren; CHEN, RL.

    1988-01-01

    PHYSICAL REVIEWS 8 VOLUME 37, NUMBER 13 1 MAY 1988 Power-law fading of the frnstration eS'ect in a periodic rectanlnlar snpercondncting neiwork with increasing aspect ratio Chia-Ren Hu and Raymond Lei Chen Department of Physics, Center.... This means that those cusps in the T,2/T, o vs @/@p curve asso- ciated with a larger integer denominator q fade away fas- ter than those associated with a smaller q, leaving a less CHIA-REN HU AND RAYMOND I.EI CHEN "jerky" T,q/T, o vs +/4p curve at larger...

  16. Superconducting flux flow digital circuits

    DOEpatents

    Hietala, Vincent M. (Placitas, NM); Martens, Jon S. (Sunnyvale, CA); Zipperian, Thomas E. (Albuquerque, NM)

    1995-01-01

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs). Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics.

  17. Microwave ablation versus radiofrequency ablation in the kidney: high-power triaxial antennas create larger ablation zones than similarly sized internally cooled electrodes

    PubMed Central

    Laeseke, PF; Lee, FT; Sampson, LA; van der Weide, DW; Brace, CL

    2012-01-01

    Purpose To determine whether microwave ablation with high-power triaxial antennas creates significantly larger ablation zones than RF ablation using similarly sized internally cooled electrodes. Methods Twenty-eight 12-minute ablations were performed in an in vivo porcine kidney model. RF ablations were performed with a 200-W pulsed generator and either a single 17-gauge cooled electrode (n = 9) or three switched electrodes spaced 1.5 cm apart (n = 7). Microwave ablations were performed using one (n = 7), two (n = 3), or three (n = 2) 17-gauge triaxial antennas to deliver 90 W continuous power per antenna. Multiple antennas were powered simultaneously. Temperatures 1 cm from the applicator were measured during two RF and microwave ablations each. Animals were euthanized post-ablation and ablation zone diameter, cross-sectional area and circularity were measured. Comparisons between groups were performed using a mixed effects model with P < .05 indicating statistical significance. Results No adverse events occurred during the procedures. Three-electrode RF (mean area, 14.7 cm2) and single-antenna microwave (mean area, 10.9 cm2) ablation zones were significantly larger than single-electrode RF (mean area, 5.6 cm2; P = .001 and P = .0355, respectively). No significant differences were detected between single-antenna microwave and multiple-electrode RF. Ablation zone circularity was similar across groups (P > .05). Tissue temperatures were higher during microwave ablation (maximum temperature, 123 °C; versus 100 °C for RF). Conclusion Microwave ablation with high-power triaxial antennas created larger ablation zones in normal porcine kidneys than RF ablation with similarly sized applicators. PMID:19616970

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

    SciTech Connect

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

    2015-01-01

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

  19. Highly efficient, high-power, broadly tunable, cryogenically cooled and diode-pumped Yb:CaF2.

    PubMed

    Ricaud, S; Papadopoulos, D N; Camy, P; Doualan, J L; Moncorgé, R; Courjaud, A; Mottay, E; Georges, P; Druon, F

    2010-11-15

    We present a high-power diode-pumped Yb:CaF(2) laser operating at cryogenic temperature (77 K). A laser output power of 97 W at 1034 nm was extracted for a pump power of 245 W. The corresponding global extraction efficiency (versus absorbed pump power) is 65%. The laser small signal gain was found to be equal to 3.1. The laser wavelength could be tuned between 990 and 1052 nm with peaks that correspond well to the structure of the gain cross-section spectra registered at low temperature. PMID:21081987

  20. Performance of Upgraded Cooling System for Lhd Helical Coils

    NASA Astrophysics Data System (ADS)

    Hamaguchi, S.; Imagawa, S.; Obana, T.; Yanagi, N.; Moriuchi, S.; Sekiguchi, H.; Oba, K.; Mito, T.; Motojima, O.; Okamura, T.; Semba, T.; Yoshinaga, S.; Wakisaka, H.

    2008-03-01

    Helical coils of the Large Helical Device (LHD) are large scale superconducting magnets for heliotron plasma experiments. The helical coils had been cooled by saturated helium at 4.4 K, 120 kPa until 2005. An upgrade of the cooling system was carried out in 2006 in order to improve the cryogenic stability of the helical coils and then it has been possible to supply the coils with subcooled helium at 3.2 K, 120 kPa. A designed mass flow of the supplied subcooled helium is 50 g/s. The subcooled helium is generated at a heat exchanger in a saturated helium bath. A series of two centrifugal cold compressors with gas foil bearing is utilized to lower the helium pressure in the bath. The supplied helium temperature is regulated by rotational speed of the cold compressors and power of a heater in the bath. The mass flow of the supplied helium is also controlled manually by a supply valve and its surplus is evaporated by ten heaters at the outlet above the coils. In the present study, the performance of the cooling system has been investigated and a stable operating method has also developed. As the result, it was confirmed that the performance of the upgraded cooling system satisfies the requirements.

  1. Space Radiation Superconducting Shields

    NASA Astrophysics Data System (ADS)

    R-Musenich; Calvelli, V.; Farinon, S.; Burger, W. J.; Battiston, R.

    2014-05-01

    The interest on shields to protect astronauts I long term missions against GCR has recently grown and several projects have been funded. Due to their large mass, passive shields for large volume habitable modules are no longer an option and the attention is focused on the more complex, technologically challenging active systems. Among the possible solutions, the most promising is based on huge superconducting coils having a bending power sufficient to deflect out of the habitat charged particles with kinetic energy in the order of 1 GeV. Toroidal magnet systems based wound with Ti clad MgB2 conductor is proposed and described.

  2. Natural cooling

    Microsoft Academic Search

    L. C. Fenster; A. J. Grantier

    1981-01-01

    With natural cooling, a process or area is cooled by outdoor air when the weather permits, and dependency on mechanical equipment is reduced. It should be used whenever conditions permit, and mechanical equipment should be brought on-line only when natural cooling cannot be employed. The results are minimized costs without lowered comfort or production levels, reduced costs for maintenance associated

  3. Cooling Towers, The Debottleneckers 

    E-print Network

    Burger, R.

    1998-01-01

    COOLING TOWERS, THE DEBOITLENECKERS by Robert Burger, Consultant The Burger Cooling Tower Company Dallas, Texas 75234 INTRODUCTION Power generating pl:mts :md petro-chemical works are always expanding. An on-going problem is to identify..., George, Munters Corp. "Cellular Tower Fill" CTI paper TP-67-0 I, 1967 Annual Meeting. [4] Phelps Patent 4,007,241 February 8, 1977. [5] MarJey Bulletin SB-9 5.92. [6] Burger, Robert, "Cooling Tower Technology" Textbook. Jrd edition, 1994 Chapter 6...

  4. Impact of drought on U.S. steam electric power plant cooling water intakes and related water resource management issues

    Microsoft Academic Search

    T. A. Kimmell; J. A. Veil

    2009-01-01

    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

  5. Parameters affecting the power distribution in the radio frequency discharge of large-area diffusion-cooled CO2 lasers

    Microsoft Academic Search

    A. Lapucci; S. Mascalchi; R. Ringressi

    1998-01-01

    An efficient power extraction from radio frequency (RF) excited CO 2 lasers can only be obtained by means of a uniform discharge power distribution. This distribution is mainly determined by the line-effect produced by the discharge structure. In this paper we report on a set of measurements performed on the luminosity of a large-area discharge showing the role played by

  6. Optimum Reflector Configurations for Minimizing Fission Power Peaking in a Lithium-Cooled, Liquid-Metal Reactor with Sliding Reflectors

    Microsoft Academic Search

    Michael L. Fensin; David I. Poston

    2005-01-01

    Many design constraints limit the development of a space fission power system optimized for fuel performance, system reliability, and mission cost. These design constraints include fuel mass provisions to meet cycle-length requirements, fuel centerline and clad temperatures, and clad creep from fission gas generation. Decreasing the fission power peaking of the reactor system enhances all of the mentioned parameters. This

  7. Wind turbine generators using superconducting coils and bulks

    NASA Astrophysics Data System (ADS)

    Ohsaki, H.; Terao, Y.; Sekino, M.

    2010-06-01

    Wind power generation has been expected as a promising clean energy source in the world. Recently, generation capacity produced by wind power generators has been growing with increasing size of windmills. However, huge nacelles result in extreme load for towers supporting them. We have focused on a wind power generator using superconducting wires and superconducting bulks to solve the problem. Large currents may flow through superconducting wires with zero DC resistance. Superconducting bulks are magnetic shielding materials. These enable reduction of size and weight of nacelles. In addition, large generators using these materials can generate an output power of 10 MW with very large power densities. This paper describes calculation of generated magnetic field and power generation characteristics using three-dimensional finite element method (FEM) analysis of the generators using high temperature superconducting coils and bulks.

  8. The effects of temperature and rf power level on the tuning of the water-cooled SSC Low-Energy Booster cavity

    SciTech Connect

    Friedrichs, C. [Los Alamos National Lab., NM (United States); Hulsey, G. [Superconducting Super Collider Lab., Dallas, TX (United States)

    1993-06-01

    The SSC Low-Energy Booster (LEB) cavity must rapidly tune from 47.52 to 59.78 MHz. The cavity tuner will use transversely biased ferrite control of the cavity resonance. The thermal expansion of a cavity`s materials affects its resonance. There are two other known temperature mechanisms that affect resonance in the water-cooled LEB cavity. The saturation magnetization of the ferrite is a function of temperature, and since the ferrite permeability is dependent on the saturation magnetization, the ferrite permeability is also temperature dependent. The ferrite cooling water is present in the tuner rf field, hence the water permittivity, which is very temperature dependent, also affects cavity resonance. While taking data on the SSC Test Cavity to quantify the effect of temperature on the resonance, we observed that the rf power level also perturbed the resonance. It was readily apparent from the data that the power level affected the resonance much more strongly at low values of control bias than at high values. In fact, when we calculate an apparent modified control-bias H field that produces the observed resonance shift, we noticed an almost perfect, though non-linear, correlation between the ratio of H{sub rf} to H{sub bias} and the apparent modified bias field, H{sub app}. This paper will present a set of equations to predict the resonance shifts produced by changes in temperature and rf power level. It will also present the techniques, both theoretical and empirical, by which these equations are derived. Finally, some of the methods for dealing with these resonance shifts will be discussed.

  9. The effects of temperature and rf power level on the tuning of the water-cooled SSC Low-Energy Booster cavity

    SciTech Connect

    Friedrichs, C. (Los Alamos National Lab., NM (United States)); Hulsey, G. (Superconducting Super Collider Lab., Dallas, TX (United States))

    1993-01-01

    The SSC Low-Energy Booster (LEB) cavity must rapidly tune from 47.52 to 59.78 MHz. The cavity tuner will use transversely biased ferrite control of the cavity resonance. The thermal expansion of a cavity's materials affects its resonance. There are two other known temperature mechanisms that affect resonance in the water-cooled LEB cavity. The saturation magnetization of the ferrite is a function of temperature, and since the ferrite permeability is dependent on the saturation magnetization, the ferrite permeability is also temperature dependent. The ferrite cooling water is present in the tuner rf field, hence the water permittivity, which is very temperature dependent, also affects cavity resonance. While taking data on the SSC Test Cavity to quantify the effect of temperature on the resonance, we observed that the rf power level also perturbed the resonance. It was readily apparent from the data that the power level affected the resonance much more strongly at low values of control bias than at high values. In fact, when we calculate an apparent modified control-bias H field that produces the observed resonance shift, we noticed an almost perfect, though non-linear, correlation between the ratio of H[sub rf] to H[sub bias] and the apparent modified bias field, H[sub app]. This paper will present a set of equations to predict the resonance shifts produced by changes in temperature and rf power level. It will also present the techniques, both theoretical and empirical, by which these equations are derived. Finally, some of the methods for dealing with these resonance shifts will be discussed.

  10. Natural cooling

    SciTech Connect

    Fenster, L.C.; Grantier, A.J.

    1981-11-25

    With natural cooling, a process or area is cooled by outdoor air when the weather permits, and dependency on mechanical equipment is reduced. It should be used whenever conditions permit, and mechanical equipment should be brought on-line only when natural cooling cannot be employed. The results are minimized costs without lowered comfort or production levels, reduced costs for maintenance associated with higher levels of mechanical chiller system operation, and decreased dependence on expensive, nonrenewable energy sources. This article reviews several methods of natural cooling and provides a detailed computer-based economic evaluation of each. It discusses the air-side economizer, water-side natural cooling, and combination systems.

  11. Superfast Cooling

    E-print Network

    S. Machnes; M. B. Plenio; B. Reznik; A. M. Steane; A. Retzker

    2010-01-15

    Currently laser cooling schemes are fundamentally based on the weak coupling regime. This requirement sets the trap frequency as an upper bound to the cooling rate. In this work we present a numerical study that shows the feasibility of cooling in the strong coupling regime which then allows cooling rates that are faster than the trap frequency with state of the art experimental parameters. The scheme we present can work for trapped atoms or ions as well as mechanical oscillators. It can also cool medium size ions chains close to the ground state.

  12. Thermal and electrical stabilities of solid nitrogen (SN2) cooled YBCO coated conductors for HTS magnet applications

    E-print Network

    Song, J. B.

    Recently, a cooling system using a solid cryogen such as solid nitrogen (SN2), was introduced for high temperature superconducting (HTS) magnet applications. In order to apply the SN2 cooling system successfully to HTS ...

  13. Sensing with Superconducting Point Contacts

    PubMed Central

    Nurbawono, Argo; Zhang, Chun

    2012-01-01

    Superconducting point contacts have been used for measuring magnetic polarizations, identifying magnetic impurities, electronic structures, and even the vibrational modes of small molecules. Due to intrinsically small energy scale in the subgap structures of the supercurrent determined by the size of the superconducting energy gap, superconductors provide ultrahigh sensitivities for high resolution spectroscopies. The so-called Andreev reflection process between normal metal and superconductor carries complex and rich information which can be utilized as powerful sensor when fully exploited. In this review, we would discuss recent experimental and theoretical developments in the supercurrent transport through superconducting point contacts and their relevance to sensing applications, and we would highlight their current issues and potentials. A true utilization of the method based on Andreev reflection analysis opens up possibilities for a new class of ultrasensitive sensors. PMID:22778630

  14. Novel compact superconducting cyclotron for medical applications

    NASA Astrophysics Data System (ADS)

    Dey, Malay Kanti; Gupta, Anjan Dutta; Chakrabarti, Alok

    2013-04-01

    A new design is presented for a superconducting-coil-based compact cyclotron, which has many practical benefits over conventional superconducting cyclotrons. Unlike in conventional superconducting cyclotrons, an iron yoke and poles have been avoided in this design and the azimuthally varying field is generated by superconducting sector coils. Housing the superconducting sector coils and circular coils in a single cryostat has resulted in an ultralight 25 MeV proton cyclotron weighing about 2000 kg. Further, the sector coils and the main coils are fed by independent power supplies, which allow flexibility of operation through on-line magnetic field trimming. The engineering considerations, focused on making the cyclotron ideally suited to medical applications, are described in detail.

  15. Development of large high current density superconducting solenoid magnets for use in high energy physics experiments. [Thesis

    Microsoft Academic Search

    1977-01-01

    The development of a unique type of large superconducting solenoid magnet, characterized by very high current density windings and a two-phase helium tubular cooling system is described. The development of the magnet's conceptual design and the construction of two test solenoids are described. The successful test of the superconducting coil and its tubular cooling refrigeration system is presented. The safety,

  16. Superconducting magnetic energy storage for asynchronous electrical systems

    DOEpatents

    Boenig, Heinrich J. (Los Alamos, NM)

    1986-01-01

    A superconducting magnetic energy storage coil connected in parallel between converters of two or more ac power systems provides load leveling and stability improvement to any or all of the ac systems. Control is provided to direct the charging and independently the discharging of the superconducting coil to at least a selected one of the ac power systems.

  17. Using risk-based regulations for licensing nuclear power plants : case study of gas-cooled fast reactor

    E-print Network

    Jourdan, Grégoire

    2005-01-01

    The strategy adopted for national energy supply is one of the most important policy choice for the US. Although it has been dismissed in the past decades, nuclear power today has key assets when facing concerns on energy ...

  18. 10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...associated bases for other types of nuclear power reactors. II. Explanation of Terms...Containment Structures for Nuclear Reactors,” March 16, 1972. In addition...to the Director, Office of Nuclear Reactor Regulation or Director,...

  19. 10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...associated bases for other types of nuclear power reactors. II. Explanation of Terms...Containment Structures for Nuclear Reactors,” March 16, 1972. In addition...to the Director, Office of Nuclear Reactor Regulation or Director,...

  20. 10 CFR Appendix J to Part 50 - Primary Reactor Containment Leakage Testing for Water-Cooled Power Reactors

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...associated bases for other types of nuclear power reactors. II. Explanation of Terms...Containment Structures for Nuclear Reactors,” March 16, 1972. In addition...to the Director, Office of Nuclear Reactor Regulation or Director,...