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1

Thermal optimum analyses and mechanical design of 10kA, vapor-cooled power leads for SSC superconducting magnet tests at MTL  

Microsoft Academic Search

The spiral-fin, 10-kA, helium vapor-cooled power leads have been designed for Superconducting Super Collider superconducting magnet tests at the Magnet Test Laboratory. In order to thermally optimize the parameters of the power leads, the lead diameters-which minimize the Carnot work for several different lengths, two different fin geometries, and two RRR values of the lead materials-were determined. The cryogenic refrigeration

Q. S. Shu; J. Demko; R. Dorman; D. Finan; D. Hatfield; I. Syromyatnikov; A. Zolotov; P. Mazur; T. Peterson

1992-01-01

2

Thermal optimum analyses and mechanical design of 10kA, vapor-cooled power leads for SSC superconducting magnet tests at MTL. Revision A  

Microsoft Academic Search

The spiral-fin, 10-kA, helium vapor-cooled power leads have been designed for Superconducting Super Collider superconducting magnet tests at the Magnet Test Laboratory. In order to thermally optimize the parameters of the power leads, the lead diameters-which minimize the Carnot work for several different lengths, two different fin geometries, and two RRR values of the lead materials-were determined. The cryogenic refrigeration

Q. S. Shu; J. Demko; R. Dorman; D. Finan; D. Hatfield; I. Syromyatnikov; A. Zolotov; P. Mazur; T. Peterson

1992-01-01

3

Power superconducting power transmission cable  

DOEpatents

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

Ashworth, Stephen P. (Cambridge, GB)

2003-01-01

4

Cooling of Color Superconducting Compact Stars  

E-print Network

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

David Blaschke

2006-03-26

5

Superconducting Materials, Magnets and Electric Power Applications  

NASA Astrophysics Data System (ADS)

The surprising discovery of superconductivity a century ago launched a chain of convention-shattering innovations and discoveries in superconducting materials and applications that continues to this day. The range of large-scale applications grows with new materials discoveries - low temperature NbTi and Nb3Sn for liquid helium cooled superconducting magnets, intermediate temperature MgB2 for inexpensive cryocooled applications including MRI magnets, and high temperature YBCO and BSSCO for high current applications cooled with inexpensive liquid nitrogen. Applications based on YBCO address critical emerging challenges for the electricity grid, including high capacity superconducting cables to distribute power in urban areas; transmission of renewable electricity over long distances from source to load; high capacity DC interconnections among the three US grids; fast, self-healing fault current limiters to increase reliability; low-weight, high capacity generators enabling off-shore wind turbines; and superconducting magnetic energy storage for smoothing the variability of renewable sources. In addition to these grid applications, coated conductors based on YBCO deposited on strong Hastelloy substrates enable a new generation of all superconducting high field magnets capable of producing fields above 30 T, approximately 50% higher than the existing all superconducting limit based on Nb3Sn. The high fields, low power cost and the quiet electromagnetic and mechanical operation of such magnets could change the character of high field basic research on materials, enable a new generation of high-energy colliding beam experiments and extend the reach of high density superconducting magnetic energy storage.

Crabtree, George

2011-03-01

6

Two phase cooling for superconducting magnets  

SciTech Connect

Comments on the use of two phase helium in a closed circuit tubular cooling system and some results obtained with the TPC superconducting magnet are given. Theoretical arguments and experimental evidence are given against a previously suggested method to determine helium two phase flow regimes. Two methods to reduce pressure in the magnet cooling tubes during quenches are discussed; (1) lowering the density of helium in the magnet cooling tubes and (2) proper location of pressure relief valves. Some techniques used to protect the refrigerator from too much cold return gas are also mentioned. 10 refs., 1 fig., 5 tabs.

Eberhard, P.H.; Gibson, G.A.; Green, M.A.; Ross, R.R.; Smits, R.G.; Taylor, J.D.; Watt, R.D.

1986-01-01

7

Power electronics cooling apparatus  

DOEpatents

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

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

2000-01-01

8

Cooling system for superconducting magnet  

DOEpatents

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

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

1998-01-01

9

Power cooling primer  

SciTech Connect

Power cooling technology has come a long way since the Clean Water Act was passed in the 1970s. Now, the choice between a wet, dry or hybrid cooling system depends on a host of variables. Since the initial passage of the Clean Water Act and other environmental laws in the early 1970's, both the regulations governing discharge of the resulting waste heat and the technology for complying with them have become increasingly complex. As a result, the decision as to the type of cooling system to use depends on a variety of project parameters, such as size of unit, site, and environmental constraints.

Williams, P.L. (Independent Energy, Washington, DC (United States))

1993-01-01

10

Two phase cooling for superconducting magnets  

SciTech Connect

A closed circuit tubular cooling system for superconducting magnets offers advantages of limiting boiloff and containing high pressures during quenches. Proper location of automatic valves to lower pressures and protect the refrigerator in the event of quenches is described. Theoretical arguments and exprimental evidence are given against a previously suggested method to determine He two phase flow regimes. If loss of flow occurs due to some types of refrigeration failure and transfer lines have enough heat leak to warm up, quenches are induced when the flow is restored. Examples are taken from experience with the TPC magnet.

Eberhard, P.H.; Gibson, G.A.; Green, M.A.; Ross, R.R.; Smits, R.G.; Taylor, J.D.; Watt, R.D.

1985-08-01

11

Cooling of superconducting devices by liquid storage and refrigeration unit  

DOEpatents

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

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

2013-08-20

12

Design of oil-free simple turbo type 65 K/6 KW helium and neon mixture gas refrigerator for high temperature superconducting power cable cooling  

NASA Astrophysics Data System (ADS)

For the requirement of HTS facility cooling, we propose oil-free simple turbo-type refrigerator. The working gas is a helium and neon mixture. Two single-stage turbo compressors and two expansion turbines are applied to the cycle. The rotor consists of the compressor impeller, turbine impeller and driving motor, and is supported by foil type gas bearing. The refrigerator requires two rotating machines with excellent reliability and compactness, and the motor power required is 72.5 kW for a refrigeration load of 6 kW. For the cooling of power cable, sub-cooled pressurized liquid nitrogen and a circulation pump must be provided. If the estimated distance between inter-cooling stations is quite long, for example 5 km, plural refrigerators may be set up on one cooling station.

Saji, N.; Asakura, H.; Yoshinaga, S.; Ishizawa, T.; Miyake, A.; Obata, M.; Nagaya, S.

2002-05-01

13

Sub-50-mK Electronic Cooling with Large-Area Superconducting Tunnel Junctions  

NASA Astrophysics Data System (ADS)

In electronic cooling with superconducting tunnel junctions, the cooling power is counterbalanced by the interaction with phonons and by the heat flow from the overheated leads. We study aluminum-based coolers that are equipped with a suspended normal metal and an efficient quasiparticle drain. At intermediate temperatures, the phonon bath of the suspended normal metal is cooled. By adjusting the junction transparency, we control the injection current and, thus, the temperature of the superconducting lead at the optimum cooling point. The best device shows remarkable cooling from 150 mK down to about 30 mK, a factor of 5 in temperature at a power of 40 pW. We discuss heat transport in our device and the reasons for cooling saturation at the low-temperature end.

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

2014-11-01

14

Inhomogeneous color superconductivity and the cooling of compact stars  

E-print Network

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

M. Ruggieri

2007-04-13

15

Status of superconducting power transformer development.  

National Technical Information Service (NTIS)

Development of the superconducting transformer is arguably the most difficult of the ac power applications of superconductivity - this is because of the need for very low ac losses, adequate fault and surge performance, and the rigors of the application e...

R. C. Johnson, B. W. McConnell, S. P. Mehta

1996-01-01

16

Efficient cooling of superconducting fiber core via holey cladding  

NASA Astrophysics Data System (ADS)

Superconductivity has the potential to alter the entire landscape of technological advancement and innovation. Unfortunately, its true potential has been limited, in part, by the lack of conventional geometries, adequate stability, cooling efficiencies and in turn, cost. In this study, we demonstrate an optical fiber design with a superconducting core that is cooled via the flow of liquid helium in holes disposed in the fused silica cladding. The efficiently micro cooled superconducting fiber lends itself to low current electronic applications such as ultrasensitive sensing and imaging, quantum measurement instrumentation and supercomputing. Although not presently applicable for large scale applications such as high current transmission lines or motors, the basic approach may be combined with other traditional technologies to improve cooling efficiency and reliability.

Homa, Daniel; Kaur, Gurbinder; Pickrell, Gary; Liang, Yongxuan

2014-05-01

17

Electrical Power Devices Cooling Technique.  

National Technical Information Service (NTIS)

The apparatus for cooling a high power electrical transformer and electrical motors uses thermally conductive material interleaved between the turn layers of a high power transformer and iron core laminates to provide a low resistant thermal path to ambie...

E. Sines

1999-01-01

18

Direct cooled power electronics substrate  

DOEpatents

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

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

2010-09-14

19

Cyrogenic testing of 100 m superconducting power transmission test facility  

Microsoft Academic Search

This follow-up study to the 1980 tests of a three-expander configuration are the final tests of the cryogenic system designed to cool the facility for testing 100 m superconducting power transmission cables. The system was modified to incorporate a fourth turbo expander remote from the refrigerator at the far end of the load. The system is described with a flow

R. J. Gibbs; J. E. Jensen; R. A. Thomas

1982-01-01

20

The electrical aspects of the choice of former in a high Tc superconducting power cable  

Microsoft Academic Search

Centrally located in a superconducting power cable the former supplies a rigid means onto which to wind the superconducting tapes and enables a continuous supply of cooling power via a flow of liquid cryogen through it. Therefore, the choice of former has a broad impact on the construction and design of a cable. The diameter of the former determines the

C. Traeholt; A. Kuhle; S. K. Olsen; O. Tonnesen

1999-01-01

21

Cooling of Neutron Stars with Color Superconducting Quark Cores  

E-print Network

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

David Blaschke; Dmitri N. Voskresensky; Hovik Grigorian

2005-10-27

22

Solar-powered cooling system  

DOEpatents

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

Farmer, Joseph C

2013-12-24

23

Heat pipe cooled power magnetics  

NASA Technical Reports Server (NTRS)

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

Chester, M. S.

1979-01-01

24

Superconductivity for electric power systems: Program overview  

SciTech Connect

Largely due to government and private industry partnerships, electric power applications based upon high-temperature superconductivity are now being designed and tested only seven years after the discovery of the high-temperature superconductors. These applications offer many benefits to the national electric system including: increased energy efficiency, reduced equipment size, reduced emissions, increased stability/reliability, deferred expansion, and flexible electricity dispatch/load management. All of these benefits have a common outcome: lower electricity costs and improved environmental quality. The U.S. Department of Energy (DOE) sponsors research and development through its Superconductivity Program for Electric Power Systems. This program will help develop the technology needed for U.S. industries to commercialize high-temperature superconductive electric power applications. DOE envisions that by 2010 the U.S. electric power systems equipment industry will regain a major share of the global market by offering superconducting products that outperform the competition.

Not Available

1995-02-01

25

Flow Cooling of Superconducting Magnets for Spacecraft Applications  

NASA Astrophysics Data System (ADS)

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, and efficient, with long maintenance-free lifetimes. Furthermore, the technology scales well to high-cooling capacities. The feasibility of using turbo-Brayton coolers in this application was proven in a design exercise in which existing cooler designs were scaled to provide cooling for the magnet sets required by 200 kW and 1 MW VASIMR engines. The performance of the concepts for the thermal interface and the thermal isolation and support system were measured in separate laboratory tests with a demonstration system built about a representative HTS magnet. Cooling for these tests was provided by a flow cooling loop comprising a compressor, recuperator and GM cryocooler, with the flow pressure, temperature, and mass flow rate selected to effectively simulate the turbo-Brayton operating condition. During system testing, the magnet was cooled below its design operating temperature of 35 K, and good thermal uniformity (<0.4 K) and low thermal loads (<0.5 W) were demonstrated.

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

2008-03-01

26

Heat Pipes Cool Power Magnetics  

NASA Technical Reports Server (NTRS)

Configurations originally developed for space use are effective in any orientation. Heat pipes integrated into high-power, high-frequency, highvoltage spaceflight magnetics reduce weight and improve reliability by lowering internal tempertures. Two heat pipes integrated in design of power transformer cool unit in any orientation. Electrostatic shield conducts heat from windings to heat pipe evaporator. Technology allows dramatic reductions in size and weight, while significantly improving reliability. In addition, all attitude design of heat pipes allows operation of heat pipes independent of local gravity forces.

Hansen, I.; Chester, M.; Luedke, E.

1983-01-01

27

Thermoelectric Devices Cool, Power Electronics  

NASA Technical Reports Server (NTRS)

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

2009-01-01

28

Surface Power Radiative Cooling Tests  

NASA Astrophysics Data System (ADS)

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

Vaughn, Jason; Schneider, Todd

2006-01-01

29

Surface Power Radiative Cooling Tests  

SciTech Connect

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

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

2006-01-20

30

Study of the Lateral Force Behavior in a Field Cooled Superconducting Linear Bearing  

Microsoft Academic Search

The main characteristic of a linear superconducting magnetic bearing (SMB) is the stable levitation between the super- conductor and the magnetic source, which is, in most cases, a per- manent magnetic (PM) rail. A stable and passive levitation can be reached when the superconducting transition occurs in the pres- ence of magnetic field (field cooling—FC). The cooling process is performed

Daniel Henrique Nogueira Dias; Guilherme Gonçalves Sotelo

2011-01-01

31

Decompression cooling system operation for HTS power cable in the KEPCO power grid  

NASA Astrophysics Data System (ADS)

A 3-phase 22.9 kV/50 MVA 410 m HTS power cable system was installed at power grid of KEPCO and had been operated for 20 months. In the HTS cable system, an open type cooling system was constructed for cooling LN2 using as coolant for superconducting cable. The cooling capacity of the cooling system was 6 kW at 69 K. Subcooled LN2 flew thorough 410 m HTS cable, maintaining 69 K of operating temperature for HTS cable. The electric load had fluctuated continuously with the load status so that the cooling state was also controlled to keep stable operating condition. The consumed LN2 used for making subcooled state was refilled periodically, and the amount was 3 tons in average. During all the operating period, the HTS cable system supplied electric power stably without any problem.

Yang, H. S.; Sohn, S. H.; Lim, J. H.; Yim, S. W.; Jeon, H. J.; Jung, S. Y.; Han, S. C.; Hwang, S. D.

2014-01-01

32

Evaluation of existing cooling systems for reducing cooling power consumption  

Microsoft Academic Search

This work was designed to estimate the cooling load power consumption during the summer in the hot and humid areas of Iran. The actual electrical energy consumption for cooling systems of some typical buildings with various applications (3 residential home buildings, 2 industrial plant buildings, a trade center with 38 shops, 3 public sectors and a city hospital) in a

M. S. Hatamipour; H. Mahiyar; M. Taheri

2007-01-01

33

Simulation of the quenching of an internally cooled superconducting magnet  

SciTech Connect

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.

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

1982-01-01

34

Cyrogenic testing of 100 m superconducting power transmission test facility  

SciTech Connect

This follow-up study to the 1980 tests of a three-expander configuration are the final tests of the cryogenic system designed to cool the facility for testing 100 m superconducting power transmission cables. The system was modified to incorporate a fourth turbo expander remote from the refrigerator at the far end of the load. The system is described with a flow schematic. The tests performed and their results are presented with turbine operating conditions presented in a table. Summary and conclusions are followed by a discussion concerning the thermometry used on the cable and the + or - 10 mK accuracy quoted.

Gibbs, R.J.; Jensen, J.E.; Thomas, R.A.

1982-01-01

35

Development of binary superconducting current leads with a gas cooled normal part  

NASA Astrophysics Data System (ADS)

The design of a binary superconducting 1 kA current lead, operating between 300 K and 4.2 K, will be presented. The normal conducting part of the lead,: will be cooled by high pressure helium gas of 60 K inlet temperature. The resulting warm end temperature of the conduction cooled high-temperature superconductor (HTSC) part is about 67 K and as a consequence a magnetic stray field of 0.2 T can be tolerated. A total heat load of 0.2 W at 4.2 K has been foreseen. The required room temperature power input of the refrigerator is reduced to about 25 % as compared to an optimised conventional current lead.

Fuchs, A. M.; Anghel, A.; Jakob, B.; Pasztor, G.; Vécsey, G.; Wesche, R.

1994-08-01

36

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

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

37

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

SciTech Connect

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.

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

1994-12-31

38

Operation of a forced two phase cooling system on a large superconducting magnet  

SciTech Connect

This paper describes the operation of a forced two phase cooling system on a two meter diameter superconducting solenoid. The magnet is a thin high current density superconducting solenoid which is cooled by forced two phase helium in tubes around the coil. The magnet, which is 2.18 meters in diameter and 3.4 meters long, has a cold mass of 1700 kg. The two phase cooling system contains less than 300 liters of liquid helium, most of which is contained in a control dewar. This paper describes the operating characteristics of the LBL two phase forced cooling system during cooldown and warm up. The paper presents experimental data on operations of the magnet using either a helium pump or the refrigerator compressor to circulate two phase helium through the superconducting coil cooling tubes.

Green, M.A.; Burns, W.A.; Eberhard, P.H.; Gibson, G.H.; Pripstein, M.; Ross, R.R.; Smits, R.G.; Taylor, J.D.; Van Slyke, H.

1980-05-01

39

Sub-cooled nitrogen cryogenic cooling system for superconducting fault current limiter by using GM-cryocooler  

NASA Astrophysics Data System (ADS)

The 21st Century Frontier R&D Program was planned to develop and commercialize the inductive Superconducting Fault Current Limiter (SFCL) in Korea until 2011. The 1.2 kV/80 A inductive SFCL was planned to develop at the first year in the first phase (2001-2002) and the 6.6 kV/200 A inductive SFCL for short run operation test was planned to develop at the second and third year in the first phase (2002-2004). The experimental characteristics of conduction-cooled cooling system developed in the first year was very weak from the sudden large thermal disturbance. Therefore, the conduction-cooled cooling system was concluded not appropriate for the cryogenic technology of the application of superconducting fault current limiter. In the third year research, the improved sub-cooled nitrogen cooling system was adopted and investigated. In this paper, the characteristics of each cooling type was compared and the basic deign of ameliorated cooling system was introduced and the total heat load of the cooling system was calculated and compared with the heat load of the cooling system developed at 2nd year research.

Kang, Hyoungku; Kim, Hyung Jin; Bae, Duck Kweon; Ahn, Min Cheol; Chang, Ho-Myung; Ko, Tae Kuk

2005-01-01

40

Cryogenic System for a High Temperature Superconducting Power Transmission Cable  

SciTech Connect

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

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

1999-07-12

41

Simulation of Thermal Processes in Superconducting Pancake Coils Cooled by GM Cryocooler  

NASA Astrophysics Data System (ADS)

This article presents the thermal model of a small scale superconducting magnetic energy storage system with the closed cycle helium cryocooler. The authors propose the use of contact-cooled coils with maintaining the possibility of the system reconfiguring. The model assumes the use of the second generation superconducting tapes to make the windings in the form of flat discs (pancakes). The paper presents results for a field model of the single pancake coil and the winding system consisting of several coils.

Lebioda, M.; Rymaszewski, J.; Korzeniewska, E.

2014-04-01

42

Potential Refrigerants for Power Electronics Cooling  

SciTech Connect

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

Starke, M.R.

2005-10-24

43

On the efficiency at maximum cooling power  

NASA Astrophysics Data System (ADS)

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.

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

2013-08-01

44

ASSESSING POWER PLANT COOLING WATER INTAKE SYSTEM  

E-print Network

ASSESSING POWER PLANT COOLING WATER INTAKE SYSTEM ENTRAINMENT IMPACTS Prepared For: California that the uses of this information will not infringe upon privately owned rights. This report has not been and recognizing the importance of publishing this work so it could be used by other researchers and decision

45

Cooling by heating: refrigeration powered by photons.  

PubMed

We propose a new mechanism for refrigeration powered by photons. We identify the strong coupling regime for which maximum efficiency is achieved. In this case, the cooling flux is proportional to T in the low temperature limit T?0. PMID:22540566

Cleuren, B; Rutten, B; Van den Broeck, C

2012-03-23

46

IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, VOL. 14, NO. 2, JUNE 2004 883 Design and Cooling Characteristic Results  

E-print Network

-cooled cryogenic cooling system for 1.2 kV/80 A inductive Superconducting Fault Current Limiter (SFCL with very large variation of currents like SFCL. Therefore, we replaced the conduction-cooled system with the sub-cooled nitrogen system for the 6.6 kV/200 A SFCL. In this paper, the design techniques and test

Chang, Ho-Myung

47

Hydrogen cooling options for MgB2-based superconducting systems  

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

48

Application of Superconducting Power Cables to DC Electric Railway Systems  

NASA Astrophysics Data System (ADS)

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

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

49

Conduction-Cooled Brass Current Leads for a Resistive Superconducting Fault Current Limiter (SFCL) System  

Microsoft Academic Search

This paper presents the design and performance results of a pair of conduction-cooled brass current leads for a resistive superconducting fault current limiter (SFCL) system. The 24 kV class SFCL, which has been recently developed by the KEPRI-LSIS collaboration group in Korea, requires three pairs of conduction-cooled brass current leads operated continuously at 630 A. When the SFCL system is

H. G. Lee; H. M. Kim; B. W. Lee; I. S. Oh; H.-R. Kim; O. B. Hyun; J. Sim; H. M. Chang; J. Bascunan; Y. Iwasa

2007-01-01

50

Hybrid Wet/Dry Cooling for Power Plants (Presentation)  

SciTech Connect

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

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

2006-02-01

51

Steam-Electric Power-Plant-Cooling Handbook  

SciTech Connect

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

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

1982-02-01

52

Theoretical analysis for the transient behaviour of radiative cooling of cavities in superconducting LINAC cryomodule  

NASA Astrophysics Data System (ADS)

For the superconducting linear accelerator program, three cryomodules each houses eight superconducting cavities were successfully developed at IUAC, New Delhi. In each cryomodule, the cold mass at 4.2 K is surrounded by the liquid nitrogen cooled thermal shield maintained at 100 K. Three stages of cooling namely, radiation cooling followed by liquid nitrogen pre-cooling and finally liquid helium (LHe) cooling, are followed to reduce the temperature of cold mass from 300 to 4.2 K. The cold mass at 4.2 K consists of cavities, LHe vessel and the support structure. The temperature of cavity and helium vessel reaches to 210-220 K in 40 h of time by the natural radiation from the thermal shield. The radiative cooling rates for the cavities, helium vessel and support structure are found to be 3.0, 4.0 and 2.0 K/h respectively. A detailed analytical calculation has been done to understand the transient cool-down phenomenon for each component and compared with the experimental measured values. The experimental values are in agreement with the analytical data within 5 % variation considering the correction factor of radiation funneling. This paper presents the role of different thermal parameters like shield temperature, conduction load and radiation funneling area in the transient radiative cool-down behaviour of different components.

Datta, T. S.; Kar, Soumen; Chacko, Jacob; Choudhury, Anup; Antony, Joby; Babu, Suresh; Kumar, Manoj

2014-06-01

53

Power producing dry cooling apparatus and method  

SciTech Connect

Spent steam from a steam driven electric generating power plant is condensed by heat rejection to a refrigerant in a closed loop. The closed refrigerant loop contains an expander and a compressor, and a heat exchanger in a cooling tower. The compressor and expander are integrated so that (1) in an upper cooling cycle at the upper end of the ambient or air temperature range, only the compressor is operated within its operating range; (2) in a lower cooling cycle at the lower end of the ambient or air temperature range, only the expander is operated and; (3) in a middle cooling cycle at the middle range of the ambient or air temperatures, when the turn-down of either the compressor or the expander is a limiting factor, both of them are operated. The characteristics of the compressor and the expander are advisably matched such that when both are operated the duties on both are balanced above their respective turn-down limits thus minimizing the energy loss and enhancing the power producing capability of the system. The integrated compressor/expander operation, during the middle range of the ambient or air temperatures in which the system is designed to operate, will also provide smoother operation, as the discontinuity going to and from the compressor to the expander mode of operation is eliminated.

Husain, M.; Lai, B.; Maher, J.B.

1981-09-29

54

Heat pipe cooling of power processing magnetics  

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

55

Polk power station syngas cooling system  

SciTech Connect

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

Jenkins, S.D.

1995-01-01

56

Development of a High Field Superconducting Magnet Cooled by a 2 K Cryocooler (1) — Magnet and Cooling System  

NASA Astrophysics Data System (ADS)

A high field magnet cooled by a small 2 K cryocooler has been developed. The superconducting magnet consists of one NbTi coil and two Nb3Sn coils. The innermost bore is 30 mm. The designed value of magnetic field is 18 T. A GM/JT cryocooler, which has a capacity of 1 W at 1.8 K has been developed for cooling this magnet. A single stage GM cryocooler is also used for cooling current leads and thermal shield. The coils were mounted on a copper plate with a cave, which was connected to the JT circuit. Each coil was attached to the copper plate with pure aluminum foil to improve thermal conduction. The magnet was cooled from room temperature to 4 K within about 80 hours and cooled from 4 K to 2 K within 10 minutes. The lowest temperature of coils was 1.67 K, and the maximum temperature difference between the coils and the copper plate was 0.02 K except during the excitation period. During excitation process the magnet temperature increased gradually as the operation current increased. However, we could hold the magnet temperature less than 2.1 K and succeeded to generate 17.3 T, which is the world highest field in a conduction-cooled magnet using a cryocooler.

Sato, A.; Nimori, S.; Numazawa, T.; Maeda, M.; Matsumoto, F.; Nagai, H.; Takahashi, M.; Kuriyama, T.; Ito, T.; Okamura, T.

2004-06-01

57

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

NASA Astrophysics Data System (ADS)

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

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

2013-03-01

58

Experimental validation of field cooling simulations for linear superconducting magnetic bearings  

NASA Astrophysics Data System (ADS)

For practical stability of a superconducting magnetic bearing the refrigeration process must occur with the superconductor in the presence of the magnetic field (a field cooling (FC) process). This paper presents an experimental validation of a method for simulating this system in the FC case. Measured and simulated results for a vertical force between a high temperature superconductor and a permanent magnet rail are compared. The main purpose of this work is to consolidate a simulation tool that can help in future projects on superconducting magnetic bearings for MagLev vehicles.

Dias, D. H. N.; Motta, E. S.; Sotelo, G. G.; de Andrade, R., Jr.

2010-07-01

59

Study of high field superconducting solenoids for muon beam cooling  

SciTech Connect

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

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

2007-08-01

60

Feasibility of electric power transmission by DC superconducting cables  

Microsoft Academic Search

The electrical characteristics of dc superconducting cables of two power ratings were studied: 3 GW and 500 MW. Two designs were considered for each of the two power ratings. In the first design, the SUPPLY stream of the cryogen is surrounded by the high-voltage high-temperature superconductor cylinder. The RETURN stream of the cryogen is on the grounded side of the

Pritindra Chowdhuri; Chandralekha Pallem; Jonathan A Demko; Michael J Gouge

2005-01-01

61

Development of a Bi2223 insert coil for a conduction-cooled 19 T superconducting magnet  

Microsoft Academic Search

We designed and have been fabricating a conduction-cooled 19 T superconducting magnet consisting of a NbTi coil, Nb3Sn coils and a Bi2223 insert coil. The insert coil is made up of 25 double-pancake coils, which are wound with the conductors composed of an Ag-sheathed Bi2223 tape and a stainless steel tape for reinforcement. The inner diameter and the outer diameter

Kenji Tasaki; Michitaka Ono; Toru Kuriyama; Satoshi Hanai; Hiroyuki Takigami; Hirohisa Takano; Kazuo Watanabe; Satoshi Awaji; Gen Nishijima; Kazumasa Togano

2005-01-01

62

Emerging Two-Phase Cooling Technologies for Power Electronic Inverters  

Microsoft Academic Search

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

2005-01-01

63

Performance Analysis of XCPC Powered Solar Cooling Demonstration Project  

NASA Astrophysics Data System (ADS)

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

Widyolar, Bennett K.

64

Impact of superconductive magnetic energy storage on electric power transmission  

Microsoft Academic Search

The authors demonstrate that a superconductive magnetic energy storage (SMES) system can provide a significant positive impact on electric power transmission. By using SMES, transmission-line loadings during heavy load hours can be reduced if the SMES system is located near the major load. Transmission losses as well as the fuel cost for the losses over a 24 hr period can

K.-S. Tam; P. Kumar

1990-01-01

65

NUCLEAR POWER STATIONS WITH LIGHT-WATER COOLED OR GAS COOLED REACTORS  

Microsoft Academic Search

The measurements, weights, and plant costs of a nuclear power plant with ; water cooled and gas cooled reactors with a power of 100 Mw (el) are compared. ; The fuel supply, the enrichment, and the recovery of irradiated fuel elements are ; briefly described, and the analysis of the fuel costs as well as fuel efficiency ; is considered.

Schuller

1958-01-01

66

Hybrid Cooling Systems for Low-Temperature Geothermal Power Production  

SciTech Connect

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

Ashwood, A.; Bharathan, D.

2011-03-01

67

Design and fabrication of double pancake coil using 2G wire for conduction cooled superconducting magnet  

NASA Astrophysics Data System (ADS)

A large bore double pancake coil(DPC) was designed and tested with 2G HTS wire to develop the conduction cooled superconducting magnet with central field intensity of 3 T at 20 K operating temperature and clear bore of 100 mm at room temperature. The effect of insulation between turns of double pancake coils was tested. Two double pancake coils with and without turn to turn insulation were wound using 4 mm wide 2G conductor. A temporary result suggests that the coil wound without electrical insulation can be protected from higher over current and shows improved stability.

Yoon, S. W.; Lee, H. J.; Moon, S. H.; Park, S. H.; Han, J.; Choi, K.; Hong, G. W.

68

Inverter power module with distributed support for direct substrate cooling  

DOEpatents

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

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

2012-08-21

69

Long range inductive power transfer with superconducting oscillators  

SciTech Connect

Resonant inductive power transfer has demonstrated the transfer of 60 W at distances in excess of 2 m with as much as 40% efficiency. The loss mechanisms include internal dissipation and radiated power. By constructing superconducting oscillators and operating at lower frequencies, both of these loss mechanisms are reduced, and this same power can be transferred at distances in excess of 100 m. A performance analysis of such a system is presented, along with proposed low-loss coil and capacitor designs to achieve this performance.

Sedwick, Raymond J. [Aerospace Engineering Department, University of Maryland, College Park, MD 20742 (United States)], E-mail: sedwick@umd.edu

2010-02-15

70

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

DOEpatents

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

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

2001-01-01

71

Compact air-cooled heat sinks for power packages  

Microsoft Academic Search

The main findings of theoretical and experimental work carried out in the development of compact air-cooled heat sinks tailored for spot-cooling of power packages are presented. After formulating the particular cooling task, the thermal issues and practical constraints of a compact heat exchanger design are matched to yield three structures, i.e., microchannel, woven wire screen and porous metal fibre, to

A. Aranyosi; L. Bolle; H. Buyse

1997-01-01

72

Compact air-cooled heat sinks for power packages  

Microsoft Academic Search

The main findings of a theoretical and experimental work carried out in the development of compact air-cooled heat sinks tailored for spot-cooling of power packages are presented. After formulating the particular cooling task, the thermal issues and practical constraints of a compact heat exchanger design are matched to yield three structures, i.e., microchannel, woven wire screen and porous metal fiber,

Attila Aranyosi; L. M. R. Bolle; H. A. Buyse

1997-01-01

73

Design of de-ionised water cooling of power converters  

Microsoft Academic Search

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

E. Ramchy; B. Malinowska; M. Cassir

1998-01-01

74

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

Microsoft Academic Search

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

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

2009-01-01

75

Development of a solar-powered passive ejector cooling system  

Microsoft Academic Search

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

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

2001-01-01

76

Emerging Two-Phase Cooling Technologies for Power Electronic Inverters  

SciTech Connect

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.

Hsu, J.S.

2005-08-17

77

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

Federal Register 2010, 2011, 2012, 2013

...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...

2013-06-12

78

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

Federal Register 2010, 2011, 2012, 2013

...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...

2012-12-07

79

THE ROLE OF AGING AND ONCE-THROUGH-COOLED POWER  

E-print Network

ENERGY COMMISSION David Vidaver Mike Ringer Michael Nyberg Daryl Metz Connie Leni Principal Authors David Nyberg, Darryl Metz, Connie Leni. 2009. The Role of Aging and Once-Through-Cooled Power Plants

80

Purification of condenser water in thermal power station by superconducting magnetic separation  

NASA Astrophysics Data System (ADS)

Thermal power station is made up of a steam turbine and a steam condenser which need a lot of water. The water of steam condenser should be replaced, since scales consisting of iron oxide mainly are accumulated on the surface of condenser pipes as it goes. Superconducting high gradient magnetic separation (HGMS) system has merits to remove paramagnetic substance like iron oxides because it can generate higher magnetic field strength than electromagnet or permanent magnet. In this paper, cryo-cooled Nb-Ti superconducting magnet that can generate up to 6 T was used for HGMS systems. Magnetic filters were designed by the analysis of magnetic field distribution at superconducting magnets. The result of X-ray analysis showed contaminants were mostly ?-Fe 2O 3 (hematite) and ?-Fe 2O 3 (maghemite). The higher magnetic field was applied up to 6 T, the more iron oxides were removed. As the wire diameter of magnetic filter decreased, the turbidity removal of the sample was enhanced.

Ha, D. W.; Kwon, J. M.; Baik, S. K.; Lee, Y. J.; Han, K. S.; Ko, R. K.; Sohn, M. H.; Seong, K. C.

2011-11-01

81

Convective Array Cooling for a Solar Powered Aircraft  

NASA Technical Reports Server (NTRS)

A general characteristic of photovoltaics is that they increase in efficiency as their operating temperature decreases. Based on this principal, the ability to increase a solar aircraft's performance by cooling the solar cells was examined. The solar cells were cooled by channeling some air underneath the cells and providing a convective cooling path to the back side of the array. A full energy balance and flow analysis of the air within the cooling passage was performed. The analysis was first performed on a preliminary level to estimate the benefits of the cooling passage. This analysis established a clear benefit to the cooling passage. Based on these results a more detailed analysis was performed. From this cell temperatures were calculated and array output power throughout a day period were determined with and without the cooling passage. The results showed that if the flow through the cooling passage remained laminar then the benefit in increased output power more than offset the drag induced by the cooling passage.

Colozza, Anthony J.; Dolce, James (Technical Monitor)

2003-01-01

82

Superconductivity  

SciTech Connect

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

Langone, J.

1989-01-01

83

Cryogenic analysis of forced-cooled, superconducting TF magnets for compact tokamak reactors  

SciTech Connect

Current designs for compact tokamak reactors require the toroidal- field (TF) superconducting magnets to produce fields from 10 to 15 T at the winding pack, using high-current densities to high nuclear heat loads (greater than 1 kW/coil in some instances), which are significantly greater than the conduction and radiation heat loads for which cryogenic systems are usually designed. A cryogenic system for the TF winding pack for two such tokamak designs has been verified by performing a detailed, steady-state heat-removal analysis. Helium properties along the forced-cooled conductor flow path for a range of nuclear heat loads have been calculated. The results and implications of this analysis are presented. 12 refs., 6 figs.

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

1988-10-25

84

Cryogenic analysis of forced-cooled, superconducting TF magnets for compact tokamak reactors  

NASA Astrophysics Data System (ADS)

Current designs for compact tokamak reactors require the toroidal-field (TF) superconducting magnets to produce fields from 10 to 15 T at the winding pack, using high-current densities to high nuclear heat loads (greater than 1 kW/coil in some instances), which are significantly greater than the conduction and radiation heat loads for which cryogenic systems are usually designed. A cryogenic system for the TF winding pack for two such tokamak designs has been verified by performing a detailed, steady-state heat-removal analysis. Helium properties along the forced-cooled conductor flow path for a range of nuclear heat loads have been calculated. The results and implications of this analysis are presented.

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

1988-10-01

85

Cryogenic cooling for high power laser amplifiers  

NASA Astrophysics Data System (ADS)

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

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

2013-11-01

86

Helium-cooling in fusion power plants  

Microsoft Academic Search

This paper reviews different helium-cooled first wall and blanket designs; and compares the selection of structural materials. The authors found that the solid breeder, SiC-composite material option generates the lowest amount of induced radioactivity and afterheat and has the highest temperature capability. When combined with the direct cycle gas turbine system, it has the potential to be the most economical

C. P. C. Wong; C. B. Baxi; C. J. Hamilton; R. W. Schleicher; H. Streckert

1994-01-01

87

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

88

Two-phase cooling method using R134a refrigerant to cool power electronic devices  

Microsoft Academic Search

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

Jeremy B. Campbell; Leon M. Tolbert; Curt W. Ayers; Burak Ozpineci

2005-01-01

89

POWER FROM NA COOLED REACTOR REACTOR DESIGN AND FEASIBILITY PROBLEM  

Microsoft Academic Search

Work done on the study of a Na cooled, graphite moderated nuclear ; reactor for power production is summarized. The preliminary design calculations ; and results are described for a heterogeneous, thermal reactor using rod type ; fuel elements of slightly enriched U. The total heat capacity is 300,000 kw with ; a nominal electric power producing capacity of 75,000

D. R. Bennion; R. L. Hickmott; N. A. Krohn; W. J. McCarthy; R. A. Moore; H. J. Stumpf; L. A. Waldman

1952-01-01

90

Superconductivity Technology Program for Electric Power Systems: Proceedings  

NASA Astrophysics Data System (ADS)

Twenty-seven presentations are included in viewgraph form for the wire development panel, applications development panel, and thallium workshop. Topics covered include: critical currents and microstructure of high temperature superconductor materials, thallium conductor development, and thermomechanical processing of BSCCO conductors; the processing of HTS wires and tapes using electrodeposited Tl-oxide superconductors and alternative screen printing and thermomechanical processing of Tl-oxide superconductors; approaches to practical wire development using Tl-1223; thermomechanical processing of wire from Bi- and Tl-based superconductors; cryoprocessing (freeze drying) of precursor powders for development of commercially viable high-T(sub c) conductors; synthesis and processing of Tl-based thick films and tapes; practical conductor development for electric power systems; demonstration of magnetic refrigerator for HTS electric power applications; cryogenic design of a superconducting motor; prospects for thallium thick-film processing for wire applications; on the determination of thallium, hole concentration, and oxygen stoichiometry in thallium-cuprate superconductors.

Marriott, K. B.

91

Gas-cooled reactor power systems for space  

NASA Astrophysics Data System (ADS)

Large amounts of electric power are required for some of the systems envisioned in support of SDI. Since various applications are being considered, and an overall power architecture study has not been completed, the required power levels and corresponding operating times for specific systems are not known. The characteristics of six designs for power levels of 2, 10 and 20 MWe for operating time of 1 and 7 yrs are described. The operating conditions for these arbitrary designs were chosen to minimize system specific mass. Both gas and liquid cooled reactors are considered. The designs discussed draw heavily on the Pluto project experience. Gas cooled thermal reactors coupled with Brayton cycle power conversion appear to provide reasonable multimegawatt space power systems. An advanced radiation design must be developed which can meet the mass limit assumed. The inherent high temperature capability of the reactors considered removes the reactor as a limiting condition on system performance.

Walter, Carl E.

92

Heat transfer coefficient for water cooled heat sink: application for standard power modules cooling at high temperature  

Microsoft Academic Search

This study presents an overview of water cooling methods used in the power electronic field. The first one uses the classical method with separated power module and cooling device. The second one deals with high reduction of conductive thermal resistance and could predominately be the final cooling solution in the near future. The last one, foreseen for future applications, consists

O. Karim; J.-C. Crebier; C. Gillot; C. Schaeffer; B. Mallet; E. Gimet

2001-01-01

93

Concurrent Wind Cooling in Power Transmission Lines  

SciTech Connect

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

Jake P Gentle

2012-08-01

94

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

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

95

Gas-cooled reactor power systems for space  

NASA Astrophysics Data System (ADS)

The characteristics of six designs for power levels of 2, 10, and 20 MWe for operating time of 1 and 7 years 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 LLNL. Both gas and liquid cooled reactors had been considered. Pitts and Walter reported on the results of a detailed study of a 10 MWe lithium cooled reactor in a potassium Rankine system. Unpublished results 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. The designs discussed here draw heavily on the Pluto project experience, which culminated in a successful full power ground test as reported by Reynolds. At higher power levels gas cooled reactors coupled with Brayton systems with advanced radiator designs becomes attractive.

Walter, C. E.

96

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

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

97

High temperature superconductivity technology for advanced space power systems  

NASA Technical Reports Server (NTRS)

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

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

1990-01-01

98

ORNL superconducting technology program for electric power systems  

NASA Astrophysics Data System (ADS)

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

Hawsey, R. A.

1994-04-01

99

Novel Thermoelectric Modules for Cooling Powerful LEDs: Experimental Results  

NASA Astrophysics Data System (ADS)

We present the results of an experimental study of a cooling system based on a novel thermoelectric module specifically designed for thermal management of high-power light-emitting diodes (LEDs). The Seoul Semiconductor LED W724C0 device was chosen for experimental validation of the efficiency of the proposed cooling unit. Two cooling systems with identical heat sinks were tested for comparison: a state-of-the-art one based on an insulated metal substrate-printed circuit board (IMS-PCB), and a system with thermoelectric cooling. The obtained results show that use of thermoelectrics results in a considerable reduction of the LED operating temperature, providing increased light output and greatly increased LED lifetime.

Semenyuk, V.; Dekhtiaruk, R.

2013-07-01

100

Keeping Cool With Solar-Powered Refrigeration  

NASA Technical Reports Server (NTRS)

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

2003-01-01

101

Peak power and cooling energy savings of shade trees  

Microsoft Academic Search

In summer of 1992, we monitored peak power and cooling energy savings from shade trees in two houses in Sacramento, CA. The collected data include air-conditioning electricity use, indoor and outdoor dry bulb temperatures and humidities, roof and ceiling surface temperatures, inside and outside wall temperatures, insolation, and wind speed and direction. Shade trees at the two monitored houses yielded

Hashem Akbari; Dan M. Kurn; Sarah E. Bretz; James W. Hanford

1997-01-01

102

SUPERCONDUCTING PHOTOINJECTOR  

SciTech Connect

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..

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

103

Superconductivity.  

PubMed

Electrons in metals can self-organise. The complex interplay between lattice dynamics, electrostatic interaction and band structure brings forth numerous types of electronic order. Because of its spectacular phenomenology, superconductivity has enjoyed a central place among these, since its discovery nearly 100 years ago. This short introduction into one of the largest fields of condensed matter research focuses on the most fundamental experimental signatures of superconductivity--perfect conductivity and perfect diamagnetism--and their explanation. A conventional broken symmetry argument is presented, which introduces a superconducting order parameter in analogy to the case of superfluid 4He, and discusses its microscopic origin in the framework of the BCS model of superconductivity. New materials have brought to light novel forms of superconductivity. Many cases are now known which fall outside the orthodox BCS model, ranging from the high temperature superconductors, to various organic and d- and f- metal compounds. The article presents key concepts from this intense area of research and touches on the equally puzzling behaviour of many of these materials above their superconducting transition temperature. PMID:15651639

Grosche, F M

2004-01-01

104

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

NASA Astrophysics Data System (ADS)

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

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

2014-05-01

105

Thermal Stress Calculations for Heatpipe-Cooled Reactor Power Systems  

NASA Astrophysics Data System (ADS)

A heatpipe-cooled fast reactor concept has been under development at Los Alamos National Laboratory for the past several years, to be used as a power source for nuclear electric propulsion (NEP) or as a planetary surface power system. The reactor core consists of an array of modules that are held together by a core lateral restraint system. Each module includes a single heatpipe surrounded by 3-6 clad fuel pins. As part of this development effort, a partial array of a candidate heatpipe-cooled reactor is to be tested in the SAFE-100 experimental program at the Marshall Space Flight Center. The partial array comprises 19 3-pin modules, which are powered by resistance heaters. This paper describes the analyses that were performed in support of this test program, to assess thermal and structural performance and to specify the test conditions needed to simulate reactor operating conditions.

Kapernick, Richard J.; Guffee, Ray M.

2003-01-01

106

Specific power of liquid-metal-cooled reactors  

SciTech Connect

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

Dobranich, D.

1987-10-01

107

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

SciTech Connect

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

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

2007-01-01

108

Hybrid Cooling for Geothermal Power Plants: Final ARRA Project Report  

SciTech Connect

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

Bharathan, D.

2013-06-01

109

The Fundamental Power Coupler for the Spallation Neutron Source (SNS) Superconducting Cavities  

SciTech Connect

The SNS linac contains superconducting cavities with phase velocities .61 and .81 for the acceleration of H- ions. Each of the 6-cell cavities, resonant at 805 MHz at 2 degrees K, is powered by a 550 kW pulsed klystron via a coaxial coupler. The specifications for the coupler require that it withstand the full klystron power in full reflection for the duration of the RF pulse (1.3+1.5(decay) ms) at a repetition rate of 60 pps, with an average power of 48 kW. The coupler must provide a Qext of 7.3 x 105 for the medium beta and high beta cavities, respectively. A design derived from proven experience at other laboratories (primarily at KEK, for Tristan and KEK-B cavities at 508 MHz) has been adopted for the production of the 50 omega prototype couplers. The couplers include a planar coaxial window with matching compensation elements, cooled by conduction via a water system from the air side of the inner conductor. The coupler's outer conductor between the window and the cavity is actively cooled by a helium circuit with input at 5 degrees K and output at about 165 degrees K. Vacuum, arcing, infrared, and electron current monitoring and interlocking is done through several ports located near the window. The coaxial coupler is matched to a WR975 waveguide through a door-knob transition, also derived from the KEK design. Numerical calculations have been performed on the electromagnetic properties of the coupler and on the multipacting behavior of the coaxial line and window. A capacitor for DC bias will be used to control multipacting. The first coupler prototypes have been produced by industry and the results of the RF testing on them at room temperature will be presented.

I.E. Campisi; E. Daly; P. Kneisel; W. Schneider; M. Stirbet; K.M. Wilson

2001-06-01

110

Growth of muskellunge in a power plant cooling reservoir  

SciTech Connect

Because there were no known sources of brood stock muskellunge (Esox masquinongy) in South Dakota at the time of the present study, fingerling muskellunge were introduced into the heated water of a power plant cooling reservoir, to determine whether a brook stock coud be developed there. Described here is the growth of the fish during the first 2 years in the reservoir, which considerably exceeded that in other North American waters.

Wahl, J.R.; Applegate, R.L.

1981-01-01

111

Use of reclaimed water for power plant cooling.  

SciTech Connect

Freshwater demands are steadily increasing throughout the United States. As its population increases, more water is needed for domestic use (drinking, cooking, cleaning, etc.) and to supply power and food. In arid parts of the country, existing freshwater supplies are not able to meet the increasing demands for water. New water users are often forced to look to alternative sources of water to meet their needs. Over the past few years, utilities in many locations, including parts of the country not traditionally water-poor (e.g., Georgia, Maryland, Massachusetts, New York, and North Carolina) have needed to reevaluate the availability of water to meet their cooling needs. This trend will only become more extreme with time. Other trends are likely to increase pressure on freshwater supplies, too. For example, as populations increase, they will require more food. This in turn will likely increase demands for water by the agricultural sector. Another example is the recent increased interest in producing biofuels. Additional water will be required to grow more crops to serve as the raw materials for biofuels and to process the raw materials into biofuels. This report provides information about an opportunity to reuse an abundant water source -- treated municipal wastewater, also known as 'reclaimed water' -- for cooling and process water in electric generating facilities. The report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) Innovations for Existing Plants research program (Feeley 2005). This program initiated an energy-water research effort in 2003 that includes the availability and use of 'nontraditional sources' of water for use at power plants. This report represents a unique reference for information on the use of reclaimed water for power plant cooling. In particular, the database of reclaimed water user facilities described in Chapter 2 is the first comprehensive national effort to identify and catalog those plants that are using reclaimed water for cooling.

Veil, J. A.; Environmental Science Division

2007-10-16

112

A gas-cooled reactor surface power system  

NASA Astrophysics Data System (ADS)

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.

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

1999-01-01

113

A gas-cooled reactor surface power system  

SciTech Connect

A human outpost on Mars requires plentiful power to assure survival of the astronauts. Anywhere from 50 to 500 kW of electric power (kWe) will be needed, depending on the number of astronauts, level of scientific activity, and life-cycle closure desired. This paper describes a 250-kWe power system based on a gas-cooled nuclear reactor with a recuperated closed Brayton cycle conversion system. The design draws upon the extensive data and engineering experience developed under the various high-temperature gas cooled reactor programs and under the SP-100 program. The reactor core is similar in power and size to the research reactors found on numerous university campuses. The fuel is uranium 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.

Lipinski, Ronald J.; Wright, Steven A.; Lenard, Roger X.; Harms, Gary A. [Sandia National Laboratories, MS-1146, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States)

1999-01-22

114

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

SciTech Connect

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.

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

2011-07-25

115

Fault Current Constrained Decentralized Optimal Power Flow Incorporating Superconducting Fault Current Limiter (SFCL)  

Microsoft Academic Search

The addition of new generation capacity increases the fault current levels in power systems. New generation and transmission capacity additions can be limited by the fault current constraints in power systems. The superconducting fault current limiter (SFCL) has great potential as a special protection device to limit the fault current in the event of a fault in power systems. Installations

Guk-Hyun Moon; Young-Min Wi; Kisung Lee; Sung-Kwan Joo

2011-01-01

116

Cooling Unit for Electric Power Controller by using Boiling Heat Transfer  

NASA Astrophysics Data System (ADS)

In recent years, semiconductor devices have become faster and more highly integrated, and their capacity has increased. Accompanying this there has also been the increase in the rate of heat generation of devices. We have developed the boiling refrigerant type cooling unit for high power electric controller. The main features of this cooling unit is high cooling performance, low noise, and low electric power. In this study we clarified the influence of cooling air velocity and the number of rows of heat exchanger on the cooling performance of this cooling unit. And it was found that the boiling refrigerant type cooling unit for electric power controller had low noise and low electric power performance compared with conventional air-to-air type cooling unit by testing the two kinds of cooling units.

Kawaguchi, Kiyoshi; Okamoto, Yoshiyuki

117

Legionnaires' disease bacteria in power plant cooling systems: Phase 2  

SciTech Connect

Legionnaires' Disease Bacteria (Legionella) are a normal component of the aquatic community. The study investigated various environmental factors that affect Legionella profiles in power plant cooling waters. The results indicate that each of the four factors investigated (incubation temperature, water quality, the presence and type of associated biota, and the nature of the indigenous Legionella population) is important in determining the Legionella profile of these waters. Simple predictive relationships were not found. At incubation temperatures of 32/sup 0/ and 37/sup 0/C, waters from a power plant where infectious Legionella were not observed stimulated the growth of stock Legionella cultures more than did waters from plants where infectious Legionella were prevalent. This observation is consistent with Phase I results, which showed that densities of Legionella were frequently reduced in closed-cycle cooling systems despite the often higher infectivity of Legionella in closed-cycle waters. In contrast, water from power plants where infectious Legionella were prevalent supported the growth of indigenous Legionella pneumophila at 42/sup 0/C, while water from a power plant where infectious Legionella were absent did not support growth of indigenous Legionella. Some Legionella are able to withstand a water temperature of 85/sup 0/C for several hours, thus proving more tolerant than was previously realized. Finally, the observation that water from two power plants where infectious Legionella were prevalent usually supported the growth of Group A Legionella at 45/sup 0/C indicates the presence, of soluble Legionella growth promoters in these waters. This test system could allow for future identification and control of these growth promoters and, hence, of Legionella. 25 refs., 23 figs., 10 tabs.

Tyndall, R.L.; Christensen, S.W.; Solomon, J.A.

1985-04-01

118

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

SciTech Connect

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

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

2011-03-01

119

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

NASA Astrophysics Data System (ADS)

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

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

2014-08-01

120

Insulation design of cryogenic bushing for superconducting electric power applications  

NASA Astrophysics Data System (ADS)

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.

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

2013-01-01

121

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

E-print Network

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 ...

Williams, Daniel David

2012-01-01

122

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

Microsoft Academic Search

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

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

2009-01-01

123

Anomalous magnetization behavior in field-cooling magnetization versus temperature curves in Tl-1223/Ag sheathed superconducting tape  

SciTech Connect

The zero-field-cooling and the field-cooling temperature dependence of magnetization for Tl-1223/Ag superconducting tape were measured by using SQUID magnetometer at fields varying from 5 Oe to 5 T in the temperature range of 5{endash}150 K. In the field-cooling curves, some anomalous behaviors, i.e., the positive Meissner effect in the curve of 5 Oe and the diamagnetic dip effect at fields up to 5 kOe, were observed. The diamagnetic dip minimum temperature shifts to the lower temperature as increasing the external field, and the relative amplitude decreases with increasing applied field. Moreover, the dip broadens with increasing applied field. The anomalous behaviors may be attributed to the flux pinning and the flux depinning of Josephson-junction networks in the sample. The dip effect at lower fields may be ascribed to the intergrain Josephson coupling networks, and that at higher fields may be due to the intrinsic intragrain Josephson coupling networks. {copyright} {ital 1997 American Institute of Physics.}

Tang, H.; Wang, Y.Z.; Yang, Z.Q.; Zhang, C.; Hua, L.; Su, X.D.; Zeng, D.C.; Qiao, G.W. [Institute of Metal Research, Academia Sinica, 72 Wenhua Road, 110015 Shenyang, Peoples Republic of (China)] [Institute of Metal Research, Academia Sinica, 72 Wenhua Road, 110015 Shenyang, Peoples Republic of (China); de Boer, F.R. [Van der Waals-Zeeman Laboratory, University of Amsterdam, Valckenierstraat, 1018 XE Amsterdam (The Netherlands)] [Van der Waals-Zeeman Laboratory, University of Amsterdam, Valckenierstraat, 1018 XE Amsterdam (The Netherlands); Zhou, S.H.; Peng, H.T. [Changsha Research Institute of Mining and Metallurgy, Post Office Box 67, 410012 Changsha, Peoples Republic of (China)] [Changsha Research Institute of Mining and Metallurgy, Post Office Box 67, 410012 Changsha, Peoples Republic of (China)

1997-04-01

124

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

NASA Astrophysics Data System (ADS)

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

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

2011-03-01

125

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

SciTech Connect

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

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

1982-02-16

126

Fabrication of a working Bi-2223 superconducting magnet cooled by liquid nitrogen  

NASA Astrophysics Data System (ADS)

A practical Bi-2223 superconducting magnet, working in liquid nitrogen (L.N 2), was designed and fabricated. Bi-2223 tape with a critical current of 147 A was prepared by a controlled overpressure (CT-OP) process at 77.3 K in self-field. Ten double-pancake coils were resistively connected by copper terminals. The bore diameter was 54 mm ?, the magnet outer diameter was 122 mm ?, the height of the magnet was 124 mm, and the weight of the magnet was about 3 kg. The maximum magnetic field at the center of the bore was 0.48 T with an operating current of 50 A. The experimental results agree well with design predictions calculated by finite element method. AC operation was also performed, and no distortion of the voltage waveform was observed. Therefore, this Bi-2223 superconducting magnet is a suitable replacement for copper magnets designed for applications in science and technology.

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

2009-06-01

127

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

SciTech Connect

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

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

1987-06-11

128

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

NASA Astrophysics Data System (ADS)

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

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

2014-09-01

129

innovati nNREL Helps Cool the Power Electronics in Electric Vehicles  

E-print Network

innovati nNREL Helps Cool the Power Electronics in Electric Vehicles Researchers at the National for cooling power electronics devices in hybrid and electric vehicles. In collaboration with 3M and Wolverine a reduction in the size of power electronic systems and potentially reducing the overall costs of electric

130

Portable self-contained power and cooling system  

SciTech Connect

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

McCullough, J.E.

1993-07-20

131

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

SciTech Connect

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.

Wolsky, A.M.

1998-05-01

132

Forced cooling of underground electric power transmission lines : design manual  

E-print Network

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 ...

Brown, Jay A.

1978-01-01

133

USE of mine pool water for power plant cooling.  

SciTech Connect

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

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

2006-11-27

134

Simulation of cooling-water discharges from power plants  

Microsoft Academic Search

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

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

2001-01-01

135

Forced Draft Cooling Tower Performance with Diesel Power Stations  

Microsoft Academic Search

A prototype cooling tower was used to explore the potential of using cooling towers compared with radiator cooling systems with 3 MW diesel engines. The working parameters were the water mass flow rate, water inlet temperature, air mass flow rate, and humidity ratio. The water mass flow rate was relatively the most effective. Three methods of calculation were used to

YOUSEF S. H. NAJJAR

1988-01-01

136

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

SciTech Connect

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

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

2005-12-01

137

Pathogenic amoebae in power-plant cooling lakes. Final report  

SciTech Connect

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.

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

1981-06-01

138

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

Microsoft Academic Search

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

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

139

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

Code of Federal Regulations, 2013 CFR

...cooling systems for light-water nuclear power reactors. 50.46 Section...cooling systems for light-water nuclear power reactors. (a)(1...boiling or pressurized light-water nuclear power reactor fueled...

2013-01-01

140

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

...cooling systems for light-water nuclear power reactors. 50.46 Section...cooling systems for light-water nuclear power reactors. (a)(1...boiling or pressurized light-water nuclear power reactor fueled...

2014-01-01

141

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

Federal Register 2010, 2011, 2012, 2013

...Systems for Light-Water-Cooled Nuclear Power Reactors AGENCY: Nuclear Regulatory...Systems for Light-Water-Cooled Nuclear Power Reactors,'' in which the NRC...system components for light water nuclear power reactors. ADDRESSES:...

2013-10-25

142

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

Code of Federal Regulations, 2012 CFR

...cooling systems for light-water nuclear power reactors. 50.46 Section...cooling systems for light-water nuclear power reactors. (a)(1...boiling or pressurized light-water nuclear power reactor fueled...

2012-01-01

143

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

Code of Federal Regulations, 2011 CFR

...cooling systems for light-water nuclear power reactors. 50.46 Section...cooling systems for light-water nuclear power reactors. (a)(1...boiling or pressurized light-water nuclear power reactor fueled...

2011-01-01

144

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

Code of Federal Regulations, 2010 CFR

...cooling systems for light-water nuclear power reactors. 50.46 Section...cooling systems for light-water nuclear power reactors. (a)(1...boiling or pressurized light-water nuclear power reactor fueled...

2010-01-01

145

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

Microsoft Academic Search

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

Bruce Bumble; Henry G. LeDuc

1997-01-01

146

Comparison power generation by using thermoelectric modules between cooling module and power module for low temperature application  

Microsoft Academic Search

The paper presents comparison thermoelectric power generation between cooling and power modules. In order to investigate which type of TE module is suitable for the power generation at low temperature of hot side of TE, four TE modules were considered: two TE cooling modules (TE model TEC1-12708 and MT2-1.-127) and two TE power modules (TE model TEP1-1264-3.4 and TEG1-1260-5.1) for

S. Maneewan; B. Zeghmati

2007-01-01

147

Study on design of superconducting proton linac for accelerator driven subcritical nuclear power system  

E-print Network

As a prior option of the next generation of energy source, the accelerator driven subcritical nuclear power system (ADS) can use efficiently the uranium and thorium resource, transmute the high-level long-lived radioactive wastes and raise nuclear safety. The ADS accelerator should provide the proton beam with tens megawatts. The superconducting linac (SCL) is a good selection of ADS accelerator because of its high efficiency and low beam loss rate. It is constitute by a series of the superconducting accelerating cavities. The cavity geometry is determined by means of the electromagnetic field computation. The SCL main parameters are determined by the particle dynamics computation

Yu Qi; Xu Tao Guang

2002-01-01

148

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

Code of Federal Regulations, 2011 CFR

...procedures for turbine engine powered airplanes. 23.1045 Section 23.1045 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045...procedures for turbine engine powered airplanes. (a) Compliance with §...

2011-01-01

149

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

Code of Federal Regulations, 2013 CFR

...procedures for turbine engine powered airplanes. 23.1045 Section 23.1045 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045...procedures for turbine engine powered airplanes. (a) Compliance with §...

2013-01-01

150

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

Code of Federal Regulations, 2011 CFR

...procedures for reciprocating engine powered airplanes. 23.1047 Section 23.1047 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047...procedures for reciprocating engine powered airplanes. Compliance with § 23.1041...

2011-01-01

151

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

Code of Federal Regulations, 2012 CFR

...procedures for reciprocating engine powered airplanes. 23.1047 Section 23.1047 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047...procedures for reciprocating engine powered airplanes. Compliance with § 23.1041...

2012-01-01

152

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

Code of Federal Regulations, 2010 CFR

...procedures for reciprocating engine powered airplanes. 23.1047 Section 23.1047 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047...procedures for reciprocating engine powered airplanes. Compliance with § 23.1041...

2010-01-01

153

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

Code of Federal Regulations, 2010 CFR

...procedures for turbine engine powered airplanes. 23.1045 Section 23.1045 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045...procedures for turbine engine powered airplanes. (a) Compliance with §...

2010-01-01

154

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

Code of Federal Regulations, 2013 CFR

...procedures for reciprocating engine powered airplanes. 23.1047 Section 23.1047 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047...procedures for reciprocating engine powered airplanes. Compliance with § 23.1041...

2013-01-01

155

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

...procedures for reciprocating engine powered airplanes. 23.1047 Section 23.1047 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1047...procedures for reciprocating engine powered airplanes. Compliance with § 23.1041...

2014-01-01

156

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

Code of Federal Regulations, 2012 CFR

...procedures for turbine engine powered airplanes. 23.1045 Section 23.1045 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045...procedures for turbine engine powered airplanes. (a) Compliance with §...

2012-01-01

157

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

...procedures for turbine engine powered airplanes. 23.1045 Section 23.1045 Aeronautics...UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Powerplant Cooling § 23.1045...procedures for turbine engine powered airplanes. (a) Compliance with §...

2014-01-01

158

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

SciTech Connect

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

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

2011-01-19

159

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

Microsoft Academic Search

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

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

1991-01-01

160

Remote Measurement of Heat Flux from Power Plant Cooling Lakes  

SciTech Connect

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

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

2013-01-01

161

Simulation of cooling-water discharges from power plants.  

PubMed

Accurate simulation of the temperature distribution in a cooling lake or reservoir is often required for feasibility studies of engineering options that increase the cooling capacity of the waterbody. A three-dimensional hydrodynamic and temperature model has been developed and applied to several cooling lakes in the south-eastern United States. In this paper, the details of the modeling system are presented, along with the application to the Flint Creek Lake. PMID:11381460

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

2001-01-01

162

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

SciTech Connect

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

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

1982-10-01

163

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

NASA Technical Reports Server (NTRS)

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

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

1999-01-01

164

The impact of high temperature superconductivity on the electric power sector  

SciTech Connect

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

Wolsky, A.M.

1996-01-01

165

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

NASA Astrophysics Data System (ADS)

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

Hegazy, Ahmed Sabry

166

Predicted cooling powers for multilayer capacitors based on various electrocaloric and electrode materials  

NASA Astrophysics Data System (ADS)

We argue that the multilayer capacitor (MLC) geometry is ideal for electrocaloric cooling. Thermal modeling predicts that a commercially available MLC, which serendipitously shows electrocaloric effects, could constitute the heart of an idealized heat pump delivering a continuous cooling power of 22.5 W kg-1. This figure could be increased via materials optimization to ˜2875 W kg-1, such that an MLC array whose sheet area is just ˜0.56 m2 would deliver the ˜20 kW cooling power of typical air-cooled chillers for air-conditioning at residential and commercial sites. Expensive materials are not required, and performance could be further enhanced via geometrical improvements.

Kar-Narayan, S.; Mathur, N. D.

2009-12-01

167

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

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

168

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

PubMed

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

Kaya, Mehmet

2014-01-01

169

A hybrid superconducting fault current limiter for enhancing transient stability in Korean power systems  

NASA Astrophysics Data System (ADS)

Additional power generation sites have been limited in Korea, despite the fact load demands are gradually increasing. In order to meet these increasing demands, Korea’s power system company has begun constructing new generators at existing sites. Thus, multi-unit plants can create problems in terms of transient stability when a large disturbance occurs. This paper proposes a hybrid superconducting fault current limiter (SFCL) application to enhance the transient stability of multi-unit power plants. SFCLs reduce fault currents, and limitation currents decrease the imbalance of the mechanical and electrical torque of the generators, resulting in an improvement in transient stability.

Seo, Sangsoo; Kim, Seog-Joo; Moon, Young-Hwan; Lee, Byongjun

2013-11-01

170

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

DOEpatents

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

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

1982-07-29

171

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

DOEpatents

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

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

1984-01-01

172

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

SciTech Connect

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

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

2012-12-01

173

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

SciTech Connect

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

Shishlo, Andrei P [ORNL

2014-01-01

174

Treating secondary sewage for water use at an air-cooled power plant  

Microsoft Academic Search

The 330MW Wyodak Plant near Gillette, Wyo. is the world's largest air-cooled power plant and the largest plant to use secondary sewage treatment effluent as the primary source of water for all uses except domestic supply. These uses include ash sluicing, fire protection, auxiliary cooling, and boiler cycle makeup, with each use requiring different treatments. The water treatments used to

H. Bydalek; J. F. Kroon; A. H. Seekamp

1977-01-01

175

Cooling problems and thermal issues in high power electronics - a multi faceted design approach  

Microsoft Academic Search

This paper provides a review of some of the issues currently facing thermal designers of high power electronics. With the current market resistance to widely embrace advanced methods such as liquid cooling, air cooling will continue to be a popular choice (K. Azar, 8th THERMINIC workshop, 2002). As heat loads increase and system sizes reduce, further innovation and optimisation of

Masud Behnia; Luke Maguire; Graham Morrison

2004-01-01

176

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

Microsoft Academic Search

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

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

1997-01-01

177

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

Microsoft Academic Search

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

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

1997-01-01

178

A New algorithm for radioisotope concentration monitoring in cooling water outlet of nuclear power plant  

Microsoft Academic Search

In the nuclear power plant (NPP), cooling water is continuously sampled through a small pipe at the outlet before flowing back to the ocean for the purpose of radioactivity concentration monitoring in water. We propose a new algorithm to identify the artificial radioisotopes probably produced in the NPP and released into the cooling water which can be added to the

M. Sohelur Rahman; Gyuseong Cho; Sungho Chang; Jeong Hyun Shin; Junho Lee; Yun Goo Kim; Ki Hyun Park

2007-01-01

179

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...

180

Impacts of cooling technology on solder fatigue for power modules in electric traction drive vehicles  

Microsoft Academic Search

This paper presents three power module cooling topologies that are being considered for use in electric traction drive vehicles such as a hybrid electric, plug-in hybrid electric, or electric vehicle. The impact on the fatigue life of solder joints for each cooling option is investigated along with the thermal performance. Considering solder joint reliability and thermal performance, topologies using indirect

Michael O'Keefe; Andreas Vlahinos

2009-01-01

181

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

SciTech Connect

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

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

2010-06-01

182

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

NASA Astrophysics Data System (ADS)

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

Lior, N.; Koai, K.

1984-11-01

183

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

NASA Astrophysics Data System (ADS)

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

Wu, Jinglin; Long, Jiaojiao; Liu, Xiaoning

2014-09-01

184

Reliability of water-cooled high-power diode laser modules  

Microsoft Academic Search

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

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

2005-01-01

185

CoolSpots: Reducing the Power Consumption of Wireless Mobile Devices with Multiple Radio Interfaces  

E-print Network

Multiple-radio systems, low-power systems, handheld de- vices, wireless communication, pervasive computingCoolSpots: Reducing the Power Consumption of Wireless Mobile Devices with Multiple Radio Interfaces. For example, for applications with low net- work-utilization the low-power/low-bandwidth interface can be used

Gupta, Rajesh

186

july/august 2010 IEEE power & energy magazine 61 School Is Cool  

E-print Network

july/august 2010 IEEE power & energy magazine 61 Where School Is Cool Power Engineering Education in Three Fast-Growing South American Energy Markets By Hugh Rudnick, Rodrigo Palma-Behnke, Sandoval. While IEEE and IEEE Power and Energy Society look for ways to entice high school students in the United

Catholic University of Chile (Universidad Católica de Chile)

187

Disorder induced power-law response of a superconducting vortex on a plane  

E-print Network

We report drive-response experiments on individual superconducting vortices on a plane, a realization for a 1+1-dimensional directed polymer in random media. For this we use magnetic force microscopy (MFM) to image and manipulate individual vortices trapped on a twin boundary in YBCO near optimal doping. We find that when we drag a vortex with the magnetic tip it moves in a series of jumps. As theory suggests the jump-size distribution does not depend on the applied force and is consistent with power-law behavior. The measured power is much larger than widely accepted theoretical calculations.

N. Shapira; Y. Lamhot; O. Shpielberg; Y. Kafri; B. J. Ramshaw; D. A. Bonn; Ruixing Liang; W. N. Hardy; O. M. Auslaender

2014-01-06

188

Experimental hybrid power transmission line with liquid hydrogen and MgB2-based superconducting cable  

NASA Astrophysics Data System (ADS)

Results of developing and testing an experimental hybrid power transmission line with liquid hydrogen and superconducting power (SCP) cable based on magnesium diboride (MgB2) are presented. Critical currents of the MgB2 based prototype SCP cable have been determined for the first time at the forced flow of liquid hydrogen in a temperature interval of 20-26 K. Various regimes of SCP cable cryostatting with both subcooled saturated liquid hydrogen have been tested in a broad range of supply rates (7-220 g/s) and pressures (0.15-0.4 MPa).

Kostyuk, V. V.; Antyukhov, I. V.; Blagov, E. V.; Vysotsky, V. S.; Katorgin, B. I.; Nosov, A. A.; Fetisov, S. S.; Firsov, V. P.

2012-03-01

189

Studies on advanced water-cooled reactors beyond generation III for power generation  

Microsoft Academic Search

China’s ambitious nuclear power program motivates the country’s nuclear community to develop advanced reactor concepts beyond\\u000a generation III to ensure a long-term, stable, and sustainable development of nuclear power. The paper discusses some main\\u000a criteria for the selection of future water-cooled reactors by considering the specific Chinese situation. Based on the suggested\\u000a selection criteria, two new types of water-cooled reactors

Xu Cheng

2007-01-01

190

Sport fishery potential of power plant cooling ponds: Final report  

SciTech Connect

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

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

1986-10-01

191

Optimized use of superconducting magnetic energy storage for electromagnetic rail launcher powering  

NASA Astrophysics Data System (ADS)

Electromagnetic rail launchers (EMRLs) require very high currents, from hundreds of kA to several MA. They are usually powered by capacitors. The use of superconducting magnetic energy storage (SMES) in the supply chain of an EMRL is investigated, as an energy buffer and as direct powering source. Simulations of direct powering are conducted to quantify the benefits of this method in terms of required primary energy. In order to enhance further the benefits of SMES powering, a novel integration concept is proposed, the superconducting self-supplied electromagnetic launcher (S3EL). In the S3EL, the SMES is used as a power supply for the EMRL but its coil serves also as an additional source of magnetic flux density, in order to increase the thrust (or reduce the required current for a given thrust). Optimization principles for this new concept are presented. Simulations based on the characteristics of an existing launcher demonstrate that the required current could be reduced by a factor of seven. Realizing such devices with HTS cables should be possible in the near future, especially if the S3EL concept is used in combination with the XRAM principle, allowing current multiplication.

Badel, Arnaud; Tixador, Pascal; Arniet, Michel

2012-01-01

192

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

SciTech Connect

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.

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

2007-01-01

193

Thermal-hydraulic tests of a recirculation cooling installation for the Rostov nuclear power station  

NASA Astrophysics Data System (ADS)

Results obtained from thermal-hydraulic tests of the recirculation cooling installation used as part of the air cooling system under the containments of the Rostov nuclear power station Units 3 and 4 are presented. The operating modes of the installation during normal operation (air cooling on the surface of finned tubes), under the conditions of anticipated operational occurrences (air cooling and steam condensation from a steam-air mixture), and during an accident (condensation of pure steam) are considered. Agreement is obtained between the results of tests and calculations carried out according to the recommendations given in the relevant regulatory documents. A procedure of carrying out thermal calculation for the case of steam condensation from a steam-air mixture on the surface of fins is proposed. The possibility of efficient use of the recirculation cooling installation in the system for reducing emergency pressure under the containment of a nuclear power station is demonstrated.

Balunov, B. F.; Balashov, V. A.; Il'in, V. A.; Krayushnikov, V. V.; Lychakov, V. D.; Meshalkin, V. V.; Ustinov, A. N.; Shcheglov, A. A.

2013-09-01

194

Flux-transfer losses in helically wound superconducting power cables  

SciTech Connect

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

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

2013-06-25

195

Flux-transfer losses in helically wound superconducting power cables  

NASA Astrophysics Data System (ADS)

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

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

2013-08-01

196

Cost analysis of power plant cooling using aquifer thermal energy storage  

SciTech Connect

Most utilities in the US experience their peak demand for electric power during periods with high ambient temperature. Unfortunately, the performance of many power plants decreases with high ambient temperature. The use of aquifer thermal energy storage (ATES) for seasonal storage of chill can be an alternative method for heat rejection. Cold water produced during the previous winter is stored in the aquifer and can be used to provide augmented cooling during peak demand periods increasing the output of many Rankine cycle power plants. This report documents an investigation of the technical and economic feasibility of using aquifer thermal energy storage for peak cooling of power plants. 9 refs., 15 figs., 5 tabs.

Zimmerman, P.W.; Drost, M.K.

1989-05-01

197

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

Microsoft Academic Search

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

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

2011-01-01

198

Powering Anomalous X-ray Pulsars by Neutron Star Cooling  

E-print Network

Using recently calculated analytic models for the thermal structure of ultramagnetized neutron stars, we estimate the thermal fluxes from young ($t\\sim 1000$ yr) ultramagnetized ($B \\sim 10^{15}$ G) cooling neutron stars. We find that the pulsed X-ray emission from objects such as 1E 1841-045 and 1E 2259+586 as well as many soft-gamma repeaters can be explained by photon cooling if the neutron star possesses a thin insulating envelope of matter of low atomic weight at densities $\\rho < 10^{7}-10^{8}$ g/cm$^3$. The total mass of this insulating layer is $M \\sim 10^{-11}-10^{-8} M_\\odot$.

Jeremy S. Heyl; Lars Hernquist

1997-08-20

199

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

NASA Astrophysics Data System (ADS)

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

Farahani, Mohsen; Ganjefar, Soheil

2013-04-01

200

Superconducting fault-current limiter and inductor design  

SciTech Connect

A superconducting fault current limiter (SFCL) that uses a biased superconducting inductor in a diode or thyristor bridge circuit was analyzed for transmission systems in 69, 138, and 230 rms kV utility transmission systems. The limiter was evaluated for costs with all components - superconducting coil, diode and/or SCR power electronics, high voltage insulation, high voltage bushings and vapor cooled leads, dewar, and refrigerator - included. A design was undertaken for the superconducting cable and coils for both diode and SCR 69 kV limiter circuits.

Rogers, J.D.; Boenig, H.J.; Chowdhuri, P.; Schermer, R.I.; Wollan, J.J.; Weldon, D.M.

1982-01-01

201

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

NASA Astrophysics Data System (ADS)

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.

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

2013-07-01

202

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

203

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

SciTech Connect

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

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

1999-04-01

204

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

SciTech Connect

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

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

2006-11-27

205

Joint operation of the superconducting fault current limiter and magnetic energy storage system in an electric power network  

NASA Astrophysics Data System (ADS)

An opportunity of using superconductors as active elements of electric power systems designed to control the electric power distribution, to enhance the systems operating modes and to limit fault currents, was very attractive for investigators for a long time. In this paper, is considered an opportunity to enhance the electric power systems with the aid of superconducting magnetic energy storage systems (SMES) and superconducting fault current limiters (SFCL) operating together. It has been shown that the joint operation of both these superconducting devices allows additional varying of their parameters, what in turn gives a further opportunity to reduce their mass and dimensions and consequently the costs. There had been also shown an additional advantage of the SMES and SFCL joint operation consisting in that they ensure a more effective protection for a power system, preventing its uncontrolled load-off and subsequent acceleration up to the inaccessible rotation speed.

Kopylov, S. I.; Balashov, N. N.; Ivanov, S. S.; Veselovsky, A. S.; Zhemerikin, V. D.

2010-06-01

206

Optimized solar-powered liquid desiccant system to supply building fresh water and cooling needs  

Microsoft Academic Search

This paper studies the feasibility of using a solar-powered liquid desiccant system to meet both building cooling and fresh water needs in Beirut humid climate using parabolic solar concentrators as a heat source for regenerating the liquid desiccant. The water condensate is captured from the air leaving the regenerator. An integrated model of solar-powered calcium chloride liquid desiccant system for

N. Audah; N. Ghaddar; K. Ghali

2011-01-01

207

Integrated three-dimensional module heat exchanger for power electronics cooling  

DOEpatents

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

Bennion, Kevin; Lustbader, Jason

2013-09-24

208

Engineering evaluation of magma cooling-tower demonstration at Nevada Power Company's Sunrise Station  

NASA Astrophysics Data System (ADS)

The Magma Cooling Tower (MCT) process utilizes a falling film heat exchanger integrated into an induced draft cooling tower to evaporate waste water. A hot water source such as return cooling water provides the energy for evaporation. Water quality control is maintained by removing potential scaling constituents to make concentrations of the waste water possible without scaling heat transfer surfaces. A pilot-scale demonstration test of the MCT process was performed from March 1979 through June 1979 at Nevada Power Company's Sunrise Station in Las Vegas, Nevada. The pilot unit extracted heat from the powerplant cooling system to evaporate cooling tower blowdown. Two water quality control methods were employed: makeup/sidestream softening and fluidized bed crystallization. The 11 week softening mode test was successful.

1980-11-01

209

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

SciTech Connect

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

Gary Vine

2010-12-01

210

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

SciTech Connect

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

Martin, Christopher; Pavlish, John

2013-09-30

211

Development of air-cooled ceramic nozzles for a power-generating gas turbine  

Microsoft Academic Search

The development of air-cooled ceramic nozzle vanes for a power-generating gas turbine has been reported. To make up the limited temperature resistance of present ceramic materials, the utilization of a small amount of cooling air has been studied for the first-stage nozzle vanes of a 1,500 C class gas turbine. A series of cascade tests were carried out for the

T. Tsuchiya; Y. Furuse; S. Yoshino; R. Chikami; Y. Tsukuda; M. Mori

1996-01-01

212

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

Microsoft Academic Search

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

F. K. Moore; C. C. Ndubizu

1976-01-01

213

COOLING SYSTEM FOR THE MERIT HIGH-POWER TARGET EXPERIMENT  

SciTech Connect

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.

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

214

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

NASA Technical Reports Server (NTRS)

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

1974-01-01

215

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

PubMed

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

Stillwell, Ashlynn S; Webber, Michael E

2014-04-15

216

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

SciTech Connect

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

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

1996-08-01

217

Integrated CoolMOS FET\\/SiC-diode module for high performance power switching  

Microsoft Academic Search

A Si CoolMOS field effect transistor and SiC diode assembly with gate driver in boost configuration (ratings at 600V\\/12A), for power factor correction application, has been fabricated in a version of an integrated power electronic module. It uses the so-called embedded power technology, to form a three-dimensional multiple chip\\/component interconnection with the embedded chips in a co-planar ceramic substrate with

Zhenxian Liang; Bing Lu; Jacobus Daniel van Wyk; Fred C. Lee

2005-01-01

218

An integrated CoolMOS FET\\/SiC diode module for high performance power switching  

Microsoft Academic Search

A Si CoolMOS FET and SiC diode assembly with gate driver in boost configuration (ratings at 600 V\\/12 A), for power factor correction (PFC) application, has been fabricated in a version of IPEM - integrated power electronics module. It uses technology of so-called embedded power (EP), to form a three-dimensional (3-D) multiple chips\\/components interconnection with the capability of functional integration

Zhenxian Liang; Bing Lu; Jacobus Daniel van Wyk; Fred C. Lee

2004-01-01

219

Overview of the development of the advanced power system by the applied superconductivity technologies programme in Korea  

NASA Astrophysics Data System (ADS)

At the end of July 2004, DAPAS (development of the advanced power system by applied superconductivity technologies), which is a 10 year long programme, finished the first of three phases. As a result of the first phase, a process for a metre long coated conductor and the core technologies of the distribution line voltage class high temperature superconductor (HTS) power systems including cables, transformers, fault current limiters (FCLs), and motors have been developed. The ultimate goal of the HTS cable project is to develop 1 GVA class HTS transmission cables. During the first phase, a three-phase 50 MVA/22.9 kV class HTS cable of 30 m length has been developed and tested successfully; it has been installed by LS Cable Ltd. In the second phase, grid-connected HTS cables will be developed and established in the real utility line. In case of FCLs, there were two types of FCL developed during the first phase: a reactive type and a resistive type. Both types had the same project targets with the specification of 6.6 kV/200 A for three-phase, and entered the second phase with the target of a 22.9 kV class. In the case of the HTS transformer project, a 1 MVA/22.9 kV class was developed, and after the second phase this project will be considered for practical application. Technically, the optimal design and the manufacturing technologies of HTS transformers as well as the analysis tools of electromagnetic field in the transformer were developed. Furthermore, a 100 hp class motor has been developed so that the key technologies for the utilization of superconducting motors could be obtained. The developed motor consists of Bi-2223 field coils of 100 A operating current at 30 K and a closed-loop cooling system, the results of which will lead us to develop 1 and 5 MVA motors in the second and third phase, respectively. In the case of the coated conductors (CCs) programme, a batch-type co-evaporation process and a reel-to-reel pulsed laser deposition process gave us 10 m long CC tapes in February 2005. We expect that 100 m long or longer CC will be developed during the second phase.

Ryu, Kang-Sik; Jo, Young-Sik; Park, Minwon

2006-03-01

220

Informativeness of radiation monitoring on nuclear power station cooling ponds  

Microsoft Academic Search

Optimizing radiation monitoring around nuclear power stations involves obtaining the most useful information on man-made radionuclide above-background radiation fields due to discharges. One can compare monitoring methods correctly if they are used under identical conditions. Also, the data should give evidence for estimating radiation doses to the local population, particularly in accidents, since the dose limit outside the protection zone

L. I. Piskunov

1990-01-01

221

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

requirement - that isn't correct!). Therefore, 3 kW per person of waste heat is generated. Cooling water carries away waste heat in the form of sensible heat, i.e. by warming the water slightly. This warming can1. Cooling water is one-third of US water usage Basic approach: (a) estimate power consumption

Nimmo, Francis

222

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

NASA Astrophysics Data System (ADS)

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

Tari, Ilker

2013-03-01

223

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

Microsoft Academic Search

A novel MoXyTM fiber delivery device with Active Cooling Cap (ACCTM) is designed to transmit up to 180W of 532 nm laser light to treat benign prostatic hyperplasia (BPH). Under such high power tissue ablation, effective cooling is key to maintaining fiber power transmission and ensuring the reliability of the fiber delivery device To handle high power and reduce fiber

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

2011-01-01

224

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

NASA Astrophysics Data System (ADS)

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

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

2012-09-01

225

Design study of high-temperature superconducting generators for wind power systems  

NASA Astrophysics Data System (ADS)

Design study on high-temperature superconducting machines (HTSM) for wind power systems was carried out using specially developed design program. Outline of the design program was shown and the influence of machine parameters such as pole number, rotor outer diameter and synchronous reactance on the machine performance was clarified. Three kinds of generator structure are considered for wind power systems and the HTSM operated under highly magnetic saturated conditions with conventional rotor and stator has better performance than the other types of HTSM. Furthermore, conceptual structure of 8 MW, 20 pole HTSM adopting salient-pole rotor as in the case of water turbine generators and race-truck shaped HTS field windings like Japanese Maglev was shown.

Maki, N.

2008-02-01

226

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

NASA Astrophysics Data System (ADS)

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.

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

2013-10-01

227

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

NASA Astrophysics Data System (ADS)

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

Grant, Paul M.

2011-03-01

228

A conceptual design for an actively cooled high-average-power electron-beam absorber [for space power applications  

Microsoft Academic Search

A conceptual design of an electron-beam absorber system that uses water as both an energy absorber and a cooling medium is presented. This configuration uses an aluminum window to separate the water absorber from a vacuum beamline. Such an arrangement has several desirable features. First, any necessary reconfiguration for an increase or decrease in run time and\\/or beam power is

J. Van Sant; R. R. Stone; R. Hedtke; S.-W. Kang; D. Ng

1989-01-01

229

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

SciTech Connect

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

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

1998-03-01

230

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

E-print Network

. By using two localised heat exchangers we obtained additional cooling power, in the range 400 and 600 m of the system. In this manuscript we report on the evolution of the temperature of the heat exchangers available at the level of the regenerator, two copper heat exchangers were installed on the stainless steel

Boyer, Edmond

231

A solar-powered adsorption cooling system using a silica gel–water mixture  

Microsoft Academic Search

Solar-powered adsorption cooling is an attractive solar energy application. Metallic solar collectors with fins have been used to increase the thermal conductivity in solar collectors. This approach has a negative effect due to solar energy loss by reflection and heat loss resulting from the sensible heat of the metal. For these reasons, a direct-radiation absorption collector is proposed here. The

Vichan Tangkengsirisin; Atsushi Kanzawa; Takayuki Watanabe

1998-01-01

232

Occupational radiation exposure at light-water-cooled nuclear power reactors, 1969--1976  

Microsoft Academic Search

This article, which is adapted from a report by the Nuclear Regulatory Commission (Report NUREG-0323), presents an updated compilation of occupational radiation exposures at commercial light-water-cooled nuclear power reactors for the years 1969 through 1976. The information in this document was derived from reports submitted annually to the Nuclear Regulatory Commission in accordance with requirements of the Technical Specifications for

Johnson

1978-01-01

233

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

Microsoft Academic Search

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

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

1999-01-01

234

WATER CONSUMPTION AND COSTS FOR VARIOUS STEAM ELECTRIC POWER PLANT COOLING SYSTEMS  

EPA Science Inventory

The report gives results of a state-of-the-art study, addressing consumptive water use and related costs of various steam electric power plant cooling systems, the availability of water for all uses by area, and the impact of legal constraints on water use in the U.S....

235

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

Microsoft Academic Search

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 ;

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

1973-01-01

236

European development of He-cooled divertors for fusion power plants  

Microsoft Academic Search

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

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

2005-01-01

237

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

SciTech Connect

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

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

1993-01-15

238

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

Microsoft Academic Search

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

Gershon Grossman

2002-01-01

239

Comparative Analysis of Various Superconducting and Non-Superconducting Fault Current Limiting Devices Designed for Operation in a 110 kV/100 MW Power Network  

NASA Astrophysics Data System (ADS)

As it is known one of the most promising fault current limiting (FCL) devices for high-power electric networks can be the so-called transformer type superconducting fault current limiter (SFCL) with the primary winding connected to the load in series and the secondary one shortened by a fast-acting circuit-breaker. These devices when made of conventional materials can be very large and expensive - e.g., for a 100 MW circuit under protection the total mass of copper winding conductors can exceed 15 tons and the heat losses in a normal operating mode can be more than 200 kW. Therefore, using of high-temperature superconductors (HTSC) can be a solution which can sufficiently improve the mass, geometrical and operational characteristics of an FCL. Unlike other superconducting AC devices, the magnetic field in SFCL does not exceed 0.1 - 0.2 T what allows using HTSC windings even at a comparatively high level of AC losses existing nowadays. In this paper is performed a comparative analysis of various designs of SCFL with the non-superconducting FCL. It has been shown that the former have a mass by an order of magnitude lower than the latter and the rate of lowering of heat losses in a normal operating mode is the same. The equalization of costs of both designs is expected to be reached within the nearest 3 - 5 five years.

Kopylov, S. I.; Altov, V. A.; Balashov, N. N.; Ivanov, S. S.; Zheltov, V. V.; Zemerikin, V. D.

240

Development of air-cooled ceramic nozzles for a power-generating gas turbine  

SciTech Connect

The development of air-cooled ceramic nozzle vanes for a power-generating gas turbine has been reported. To make up the limited temperature resistance of present ceramic materials, the utilization of a small amount of cooling air has been studied for the first-stage nozzle vanes of a 1,500 C class gas turbine. A series of cascade tests were carried out for the designed air-cooled Si{sub 3}N{sub 4} nozzle vanes under 6 atm and 1,500 C conditions. It was confirmed that the maximum ceramic temperature can be maintained below 1,300 C by a small amount of cooling air. In spite of the increased thermal stresses from local cooling, all Si{sub 3}N{sub 4} nozzle vanes survived the cascade tests, including both steady-state and transients of emergency shutdown. The potential for an air-cooled ceramic nozzle was demonstrated for a 1,500 C class gas turbine application.

Tsuchiya, T.; Furuse, Y.; Yoshino, S. [Tokyo Electric Power Co., Yokohama, Kanagawa (Japan). Engineering R and D Center; Chikami, R.; Tsukuda, Y.; Mori, M. [Mitsubishi Heavy Industries, Ltd., Takasago, Hyogo (Japan)

1996-10-01

241

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

NASA Technical Reports Server (NTRS)

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

Schwarze, G. E.

1985-01-01

242

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

SciTech Connect

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 includes the judicious choice of conductor materials. The results of this analysis should be immediately applicable to power system trade-off studies including comparisons with ac transmission systems.

Schwarze, G.E.

1994-09-01

243

Design of a capacitive main power coupler for RF superconducting accelerators  

NASA Astrophysics Data System (ADS)

An updated main coupler has been designed for the superconducting accelerator of Free Electron Laser (FEL) project under construction in Peking University. A capacitive structure is chosen for the main coupler. Numerical investigation using CST Microwave Studio demonstrates the cold window part. The other nonstandard structures such as holding rods and antenna are also optimized. The coupler uses a 95% purity Al2O3 ceramic cold window. The VSWR (Vottage Standing Wave Ratio) is 1.02 at 1.3 GHz and the frequency bandwidth is 45 MHz with VSWR<1.1. The electric field intensity is 8.5×10-2 kV/mm around the window with 20 kW Continuous Wave (CW) transmitted power. The Qext is designed variable from 5×106 to 1×107. Supported by National Basic Research Program (2002CB713600) and NSFC (10775010)

He, Fei-Si; Hao, Jian-Kui; Zhang, Bao-Cheng; Zhao, Kui

2008-07-01

244

Development of a 500 kVA-class oxide-superconducting power transformer operated at liquid-nitrogen temperature  

NASA Astrophysics Data System (ADS)

We have designed and constructed a 500 kVA-class oxide-superconducting power transformer. The windings are cooled by liquid nitrogen or subcooled nitrogen in a G-FRP cryostat of 785 mm in diameter and 1210 mm in height, that has a room-temperature space for an iron core with the diameter of 314 mm. The primary and secondary windings are three-strand and six-strand parallel conductors of a Bi-2223 multifilamentary tape with silver sheath, respectively. The strand 0.22 mm thick and 3.5 mm wide has 61 filaments with no twisting. The ratio of superconductor is 0.284. In the parallel conductors, the strands are transposed five times in each layer for a uniform current distribution among them. It was proved that the transformer has the rated capacity of 500 kVA by means of two-h short-circuit test and half-h no-load test in liquid nitrogen of 77 K. The efficiency is estimated as 99.1% from a core loss of 2.3 kW and a thermal load of 2.2 kW in coolant. The latter is composed of AC losses in windings and heat leakage from the cryostat and current leads, and is multiplied by a refrigeration penalty of liquid nitrogen, 20. Load test was also performed up to 500 kVA. The transformer was furthermore operated in subcooled nitrogen at 66 K with no quenching up to a critical level, that is equivalent to 800 kVA. The efficiency estimated was improved to 99.3% in subcooled nitrogen. Measured a.c. loss in both windings are well explained by a theoretical prediction with the "critical state model". We also discuss prospective applications of the parallel conductors composed of advanced HTS multifilamentary tapes to a.c. windings with large current capacity.

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

245

Liquid Cooled Cold Plates for Industrial High-Power Electronic Devices---Thermal Design and Manufacturing Considerations  

Microsoft Academic Search

Electronics cooling research has been largely focused on high heat flux removal from computer chips in the recent years. However, the equally important field of high-power electronic devices has been experiencing a major paradigm shift from air cooling to liquid cooling over the last decade. For example, multiple 250-W insulated-gate bipolar transistors used in a power drive for a 7000-HP

Satish G. Kandlikar; Clifford N. Hayner II

2009-01-01

246

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

SciTech Connect

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

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

1984-01-01

247

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

NASA Astrophysics Data System (ADS)

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

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

2013-11-01

248

An assessment of the use of direct contact condensers with wet cooling systems for utility steam power plants  

Microsoft Academic Search

Potential use of a direct contact condenser for steam recovery at the turbine exhaust of a utility power plant using a wet cooling system is investigated. To maintain condensate separate from the cooling water, a bank of plate heat exchangers is used. In a case study for a nominal 130-MW steam power plant, two heat rejection systems, one using a

D. Bharathan; E. Hoo; P. DErrico

1992-01-01

249

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

NASA Astrophysics Data System (ADS)

A concept of a high-power transmitter utilizing the Continuous Wave (CW) magnetrons, injection-locked by phase-modulated signals, and intended to operate within a wideband control feedback loop in phase and amplitude, is presented. This transmitter is proposed to drive Superconducting RF (SRF) cavities for intensity-frontier GeV-scale proton/ion linacs, such as the projected Fermilab proton linacs or linacs for Accelerator Driven System (ADS). The transmitter consists of two 2-cascade injection-locked magnetrons with outputs combined by a 3-dB hybrid. The transmitter performance was modelled using CW, S-Band, 1 kW magnetrons. A wideband dynamic control of magnetrons, required for the superconducting linacs, was realized using the magnetrons, injection-locked by the phase-modulated signals. The capabilities of the magnetrons injection-locked by the phase-modulated signals and adequateness for feeding of SRF cavities have been verified by measurements of the magnetrons phase performance, by measurements of the transfer function magnitude characteristics of single and 2-cascade magnetrons in the phase modulation domain, and by measurements of spectra of carrier frequency of the magnetron. At the ratio of power of locking signal to output power of ?-13 dB (in 2-cascade scheme per magnetron) a phase modulation bandwidth is over 1.0 MHz for injection-locked CW single magnetrons and a 2-cascade setup. The carrier frequency spectra (width of ~1 Hz at the level of -60 dBc) measured with the magnetron, injection-locked by a phase-modulated signal, did not demonstrate broadening at wide range of magnitude and frequency of the phase modulation. The wideband dynamic management of output power of the transmitter model has been first experimentally demonstrated using combined in power magnetrons, injection-locked by the phase-modulated signals. Experiments with the injection-locked magnetrons adequately emulated the wideband dynamic control with a feedback control system, which will allow to suppress all known parasitic modulation of the accelerating field in the SRF cavities. The magnetron transmitter concept, tests of the transmitter models and injection-locking of magnetrons by phase-modulated signals are discussed in this work.

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

2014-10-01

250

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

SciTech Connect

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

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

1983-01-01

251

Reduction of 1/{ital f} noise in high-{ital T}{sub {ital c}} dc superconducting quantum interference devices cooled in an ambient magnetic field  

SciTech Connect

The spectral density {ital S}{sub {Phi}}({ital f}) of the low-frequency 1/{ital f} noise of high transition temperature dc superconducting quantum interference devices (SQUIDs) with narrow linewidths was independent of {ital B}{sub 0}, the magnetic field in which they were cooled, up to a threshold value, about 33 {mu}T in the best case. Above this threshold, which is associated with the entry of flux vortices into the film, the noise increased rapidly. By contrast, for large square washer SQUIDs, {ital S}{sub {Phi}}({ital f}) scaled linearly with {ital B}{sub 0}. Estimates indicate that the 1/{ital f} flux noise produced by the pickup loop of a directly coupled magnetometer is negligible. {copyright} {ital 1996 American Institute of Physics.}

Dantsker, E.; Tanaka, S.; Nilsson, P.; Kleiner, R.; Clarke, J. [Department of Physics, University of California, Berkeley, California 94720 (United States)] [Department of Physics, University of California, Berkeley, California 94720 (United States); [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

1996-12-01

252

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

SciTech Connect

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

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

2012-05-20

253

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

SciTech Connect

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

C. McGowin; M. DiFilippo; L. Weintraub

2006-06-30

254

Engineering evaluation of magma cooling-tower demonstration at Nevada Power Company's Sunrise Station. Final report  

SciTech Connect

The Magma Cooling Tower (MCT) process utilizes a falling film heat exchanger integrated into an induced draft cooling tower to evaporate wastewater. A hot water source such as return cooling water (90/sup 0/F to 110/sup 0/F) provides the energy for evaporation. Water quality control is maintained by removing potential scaling constituents to make concentration of the wastewater possible without scaling heat transfer surfaces. A pilot-scale demonstration test of the MCT process was performed from March 1979 through June 1979 at Nevada Power Company's Sunrise Station in Las Vegas, Nevada. The pilot unit extracted heat from the powerplant cooling system to evaporate cooling tower blowdown. Two water quality control methods were employed: makeup/sidestream softening and fluidized bed crystallization. The 11-week softening mode test was successful. The unit operated without biofouling or scaling at 100,000 ppM TDS levels under a wide range of operating conditions. Successful operation was not demonstrated in the 10-day crystallization mode test; calcium sulfate (CaSO/sub 4/) scaling occurred on the last day of the test at a maximum brine concentration of less than 40,000 ppM. An economic and technical comparison with other zero-discharge technologies showed that, for application at Sunrise, the MCT process had competitive capital, operating, and levelized annual costs. No major technical problems were encountered that would preclude the commercial application of a properly designed MCT unit operating in the softening mode.

Not Available

1980-11-01

255

Solar radiative cooling: a possible way to reduce temperature in steam power plant condensers  

SciTech Connect

One of the most appealing possibilities for improving efficiencies of steam power stations is related to a reduction of condenser temperature (and consequently pressure). However, the necessity of large water flows requires, as a limit case, a temperature slightly higher than the surroundings. A possible reduction of temperature with respect to the surrounding medium is made possible, without heat engines, by means of radiative cooling. It is well known that from a radiative point of view external space behaves like a black-body at very low temperature, so that an object, through radiation, could cool down sensibly, but this effect is generally prevented by the presence of the atmosphere. The aim of the paper is twofold: first of all the possible solutions for increasing the cooling effect are presented and discussed, then the technical applications to steam power stations are examined under various aspects. The possible solutions are generally related to 'transparency windows' of the atmosphere, each of them for particular wavelengths, and the effects of external conditions (humidity, cloudiness etc.) are described and analyzed. Furthermore the possibility of selective surfaces is taken into account, so that all trends in increasing cooling performances can be compared. Some experimental data of the University of Florence are presented and discussed in some detail.

Stecco, S.S.; Buzzigoli, M.

1983-12-01

256

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

SciTech Connect

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

Li, Jianjian; /IIT, Chicago

2008-12-01

257

Development of practical high temperature superconducting wire for electric power application  

NASA Technical Reports Server (NTRS)

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

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

1995-01-01

258

Development of practical high temperature superconducting wire for electric power applications  

SciTech Connect

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

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

1994-09-01

259

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

SciTech Connect

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

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

1994-12-31

260

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

SciTech Connect

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.

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

1982-04-01

261

Peak power and cooling energy savings of high-albedo roofs  

Microsoft Academic Search

In the summers of 1991 and 1992, we monitored peak power and cooling energy savings from high-albedo coatings at one house and two school bungalows in Sacramento, California. We collected data on air-conditioning electricity use, indoor and outdoor temperatures and humidities, roof and ceiling surface temperatures, inside and outside wall temperatures, insolation, and wind speed and direction. Applying a high-albedo

Hashem Akbari; Sarah Bretz; Dan M. Kurn; James Hanford

1997-01-01

262

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

Microsoft Academic Search

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

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

2005-01-01

263

Cryogenic Technology for Superconducting Accelerators  

NASA Astrophysics Data System (ADS)

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

Hosoyama, Kenji

2012-01-01

264

A HIGH POWER RF COUPLER DESIGN FOR MUON COOLING RF CAVITIES.  

SciTech Connect

We present a high power RF coupler design for an interleaved {pi}/2 805 MHz standing wave accelerating structure proposed for an muon cooling experiment at FNAL. The coupler, in its simplest form, is a rectangular waveguide directly connected to an accelerating Cell through an open slot on the cavity side-wall or end-plates. Two of such couplers are needed to feed the interleaved cavities. Current high power RF test requires the coupler to be at critical coupling. Numerical simulations on the coupler designs using MAFIA will be presented.

CORLETT,J.; LI,DERUN; RIMMER,R.; HOLTKAMP,N.; MORETTI,A.; KIRK,H.G.

1999-03-29

265

Experimental study on the cooling performance of high power LED arrays under natural convection  

NASA Astrophysics Data System (ADS)

This paper presents on the cooling performance of high power light emitting diode (LED) arrays under natural convection condition. A series of experiments with different type of LED array arrangements with a commercial heat sink were performed to evaluate their thermal performance. An analytical thermal resistance model was used to calculate thermal resistance. The results reveal that thermal resistance and junction temperature are affected by the type of array. The triangular array of the high power LED revealed the highest heat transfer coefficient with 3.86% compared to the most common square array. It indicates that array arrangement of the LED significantly affect on the excellent performance.

Mohamad, M. S.; Abdullah, M. Z.; Abdullah, M. K.

2013-12-01

266

Allocation and Circuit Parameter Design of Superconducting Fault Current Limiters in Loop Power System by a Genetic Algorithm  

NASA Astrophysics Data System (ADS)

In near future, many Independent Power Producers (IPPs) will participate in power generations according to their own strategic contracts by the deregulation. Loop or mesh systems can be designed to balance the power flow and to regulate the voltage resulting to the flexibility of power system operation, improvement of reliability and economical efficiency. Nevertheless, they bring to the problem of increased fault levels which may raise beyond the withstand capability of existing circuit breakers in the power systems. Short-circuit current is strongly related to the cost of apparatus and the effective use of power transmissions. Therefore, the introduction of Superconducting Fault Current Limiters (SFCLs) becomes an effective way for suppressing such a large short-circuit current. In this paper, first the authors evaluate the behavior of the S/N transition-type SFCL by considering the sub-transient and transient effects of generators in order to obtain smaller SFCL circuit parameters, i.e.\\ the resistance of the superconducting coil and the reactance of the current-limiting inductor. Then the authors propose a method by using a hierarchical genetic algorithm (HGA) combined with a micro-genetic algorithm (micro-GA) to search for the optimal locations and the smallest SFCL circuit parameters simultaneously. The flexibility in defining the required objective function by using the proposed method makes it possible to evaluate the requirement of SFCLs in large power systems. Analysis by computer simulation has been carried out in an example loop power system.

Hongesombut, Komsan; Furusawa, Ken; Mitani, Yasunori; Tsuji, Kiichiro

267

Heat pipe cooled reactors for multi-kilowatt space power supplies  

NASA Astrophysics Data System (ADS)

Three nuclear reactor space power system designs are described that demonstrate how the use of high temperature heat pipes for reactor heat transport, combined with direct conversion of heat to electricity, can result in eliminating pumped heat transport loops for both primary reactor cooling and heat rejection. The result is a significant reduction in system complexity that leads to very low mass systems with high reliability, especially in the power range of 1 to 20 kWe. In addition to removing heat exchangers, electromagnetic pumps, and coolant expansion chambers, the heat pipe/direct conversion combination provides such capabilities as startup from the frozen state, automatic rejection of reactor decay heat in the event of emergency or accidental reactor shutdown, and the elimination of single point failures in the reactor cooling system. The power system designs described include a thermoelectric system that can produce 1 to 2 kWe, a bimodal modification of this system to increase its power level to 5 kWe and incorporate high temperature hydrogen propulsion capability, and a moderated thermionic reactor concept with 5 to 20 kWe power output that is based on beryllium modules that thermally couple cylindrical thermionic fuel elements (TFE's) to radiator heat pipes.

Ranken, W. A.; Houts, M. G.

268

Heat pipe cooled reactors for multi-kilowatt space power supplies  

SciTech Connect

Three nuclear reactor space power system designs are described that demonstrate how the use of high temperature heat pipes for reactor heat transport, combined with direct conversion of heat to electricity, can result in eliminating pumped heat transport loops for both primary reactor cooling and heat rejection. The result is a significant reduction in system complexity that leads to very low mass systems with high reliability, especially in the power range of 1 to 20 kWe. In addition to removing heat exchangers, electromagnetic pumps, and coolant expansion chambers, the heat pipe/direct conversion combination provides such capabilities as startup from the frozen state, automatic rejection of reactor decay heat in the event of emergency or accidental reactor shutdown, and the elimination of single point failures in the reactor cooling system. The power system designs described include a thermoelectric system that can produce 1 to 2 kWe, a bimodal modification of this system to increase its power level to 5 kWe and incorporate high temperature hydrogen propulsion capability, and a moderated thermionic reactor concept with 5 to 20 kWe power output that is based on beryllium modules that thermally couple cylindrical thermionic fuel elements (TFEs) to radiator heat pipes.

Ranken, W.A.; Houts, M.G.

1995-01-01

269

Operating experience of the Southwire high temperature superconducting cable installation  

Microsoft Academic Search

Southwire Company is operating the world's first high temperature superconducting (HTS) cable at its corporate headquarters in Carrollton, Georgia. The HTS system consists of three 30 m long single phase cables rated at 12.4 kV, 1250 A and is cooled by pressurized liquid nitrogen. The cable provides power to Southwire's two main manufacturing plants and the machinery division. The cable

D. T. Lindsay

2002-01-01

270

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

NASA Astrophysics Data System (ADS)

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

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

2014-09-01

271

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

NASA Technical Reports Server (NTRS)

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

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

1987-01-01

272

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

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

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

2012-04-01

273

Fast granular superconducting bolometer  

SciTech Connect

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.

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

1984-08-07

274

Fast granular superconducting bolometer  

NASA Astrophysics Data System (ADS)

This abstract discloses 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.

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

1984-08-01

275

Electronic Coolers Based on Superconducting Tunnel Junctions: Fundamentals and Applications  

NASA Astrophysics Data System (ADS)

Thermo-electric transport at the nano-scale is a rapidly developing topic, in particular in superconductor-based hybrid devices. In this review paper, we first discuss the fundamental principles of electronic cooling in mesoscopic superconducting hybrid structures, the related limitations and applications. We review recent work performed in Grenoble on the effects of Andreev reflection, photonic heat transport, phonon cooling, as well as on an innovative fabrication technique for powerful coolers.

Courtois, H.; Hekking, F. W. J.; Nguyen, H. Q.; Winkelmann, C. B.

2014-06-01

276

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

PubMed

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

Klein, Sharon J W

2013-12-17

277

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

SciTech Connect

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.

Nelson, S.D.; Reitter, T.; Caplan, M. [and others

1995-05-12

278

Microwave properties of YBa2Cu3O(7-delta) high-transition-temperature superconducting thin films measured by the power transmission method  

NASA Technical Reports Server (NTRS)

The microwave response of YBa2Cu3O(7-delta) superconducting thin films deposited on LaAlO3, MgO, YSZ, and LaGaO3 substrates are studied. It is found that the microwave transmission properties are very weakly dependent on temperature in the normal state but change drastically upon transition to the superconducting state. In particular, the transmission decreases and there is a negative phase shift with respect to the phase at room temperature when the sample is cooled through its transition temperature. The magnetic penetration depth for all the films was determined from the surface reactance of the films. The microwave complex conductivity is determined in both the normal and the superconducting state. It is observed that both sigma1 and sigma2 increase in transition to the superconducting state. The surface resistivity is calculated for all the films.

Miranda, F. A.; Gordon, W. L.; Bhasin, K. B.; Heinen, V. O.; Warner, J. D.

1991-01-01

279

Heterogeneous Superconducting Low-Noise Sensing Coils  

NASA Technical Reports Server (NTRS)

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

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

2008-01-01

280

Application of a combined superconducting fault current limiter and STATCOM to enhancement of power system transient stability  

NASA Astrophysics Data System (ADS)

Stable and reliable operation of the power system network is dependent on the dynamic equilibrium between energy production and power demand under large disturbance such as short circuit or important line tripping. This paper investigates the use of combined model based superconducting fault current limiter (SFCL) and shunt FACTS Controller (STATCOM) for assessing the transient stability of a power system considering the automatic voltage regulator. The combined model located at a specified branch based on voltage stability index using continuation power flow. The main role of the proposed combined model is to achieve simultaneously a flexible control of reactive power using STATCOM Controller and to reduce fault current using superconducting technology based SFCL. The proposed combined model has been successfully adapted within the transient stability program and applied to enhance the transient power system stability of the WSCC9-Bus system. Critical clearing time (CCT) has been used as an index to evaluate and validate the contribution of the proposed coordinated Controller. Simulation results confirm the effectiveness and perspective of this combined Controller to enhance the dynamic power system performances.

Mahdad, Belkacem; Srairi, K.

2013-12-01

281

RESIDUAL OXIDANTS REMOVAL FROM COASTAL POWER PLANT COOLING SYSTEM DISCHARGES: FIELD EVALUATION OF SO2 ADDITION SYSTEM  

EPA Science Inventory

The report gives results of an evaluation of the performance of a dechlorination system that uses SO2 to remove residual oxidants from chlorinated sea water in a power plant cooling system. Samples of unchlorinated, chlorinated, and dechlorinated cooling water were obtained at Pa...

282

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

E-print Network

IMPACT OF THE SUN PATCH ON HEATING AND COOLING POWER EVALUATION: APPLIED TO A LOW ENERGY CELL A Renardières ­ Ecuelles, 77818 MORET-SUR- LOING Cedex, France ABSTRACT In the context of low energy buildings we study the impact of the incoming radiation through a window (sun patch) on the heating and cooling

Paris-Sud XI, Université de

283

SOLERAS - Solar Cooling Engineering Field Tests Project: United Technologies Research Center. Design guidelines for solar heating/cooling/power generation systems  

SciTech Connect

This report documents the methodology, design guidelines and analytical tools for the preliminary technical/economic evaluation of solar heating/cooling/power generation systems. In particular, it provides the theoretical framework, data bases and software tools for: determining the preliminary economic feasibility of solar-powered configurations compared with grid-supplied electric power and/or competing fossil fuels; selecting the optimum system configuration with respect to solar collector area and ''solar-side'' thermal storage capacity. Implementation of the methodology described in this report can be facilitated by the use of the accompanying IBM PC-compatible computer program ''SOLERAS''. This report represents the final task of the multi-year SOLERAS Program -- jointly sponsored by the US Department of Energy and the King Abdulaziz City for Science and Technology -- which involved the development and field-testing of a solar-powered cooling system in Phoenix, AZ. 11 refs., 37 figs.

Not Available

1987-01-01

284

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

SciTech Connect

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

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

2009-11-09

285

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

SciTech Connect

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

Farfan, E.

2009-09-30

286

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

SciTech Connect

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

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

2011-01-01

287

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

SciTech Connect

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

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

2012-07-01

288

Environmental Problems Associated with Decommissioning of Chernobyl Power Plant Cooling Pond  

NASA Astrophysics Data System (ADS)

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

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

2009-12-01

289

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

NASA Astrophysics Data System (ADS)

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.

Bell, Lon E.

2008-09-01

290

Transport and deposition of activation products in a helium cooled fusion power plant  

SciTech Connect

The transport and deposition of neutron activation products in a helium cooled tokamak fusion power plant are investigated. Stainless steel is used as coolant channel material for a helium/steam system. The important gamma emitting nuclides /sup 56/Mn, /sup 54/Mn, /sup 57/Co, /sup 58/Co, /sup 60/Co, /sup 51/Cr, and /sup 99/Mo are considered. The dominant release mechanism identified is direct daughter recoil emission from (n,x) type reactions. Corrosion and evaporation are discussed. The radionuclide inventory released by these mechanisms is predicted to exceed 1 x 10/sup 4/ Ci for a reference reactor design after only several days of operation, and approach 3.5 x 10/sup 4/ Ci in equilibrium. A mass transport model is then used to predict the deposition pattern of this inventory in the reactor cooling system.

Bickford, W.E.

1980-09-01

291

Keeping cool while planning a major cooling system modification for a large base-loaded power plant  

SciTech Connect

This paper addresses vital considerations which need to be addressed to help ensure that the wisest approach is used for evaluating or modifying existing open or closed cycle cooling systems. (authors)

Mallory, J. [Sargent and Lundy LLC, 55 East Monroe Street, Chicago, IL 60603 (United States); Randels, R. [Sargent and Lundy LLC, 1860 N. 95th Lane, Phoenix, AZ 85037 (United States); Penrose, J.; Ludovisi, D. [Sargent and Lundy LLC, 55 East Monroe Street, Chicago, IL 60603 (United States)

2012-07-01

292

Superconducting mirror for laser gyroscope  

SciTech Connect

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

Wang, X.

1991-05-14

293

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

NASA Astrophysics Data System (ADS)

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

Li, Kenneth

2014-02-01

294

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

NASA Technical Reports Server (NTRS)

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

Sinclair, J. H.

1973-01-01

295

Macrofouling communities in the cooling system of the Vladivostok heat and power plant  

NASA Astrophysics Data System (ADS)

The composition, structure, and distribution of flora and fauna on hydraulic facilities in the cooling system of the Vladivostok combined heat and power plant-2 were studied in summer and autumn of 2001. Cluster analysis was applied to differentiate Balanus rostratus, Mytilus trossulus, Jassa marmorata, Crassostrea gigas + Balanus rostratus, Modiolus modiolus + Pachycheles stevensii, Hydroides ezoensis, and Amphibalanus improvisus communities. The groups of fouling organisms found on the studied objects were shown to be assigned both to “physically controlled” and “biologically balanced” benthic communities. This study stresses the high similarity between the fouling communities of anthropogenic substrata and natural intertidal and subtidal benthic communities from adjacent areas of Peter the Great Bay.

Moshchenko, Alexander V.; Zvyagintsev, Alexander Yu.

2010-03-01

296

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

SciTech Connect

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

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

2013-09-30

297

Thermal modeling and cooling analysis of high-power lithium ion cells  

NASA Astrophysics Data System (ADS)

The heat generation model and three-dimensional computational fluid dynamics model for lithium ion cells were established with boundary conditions defined. In order to provide a better insight about the behaviors of high-power lithium ion cells under realistic discharge conditions, the temperature difference of the cells and an active thermal management system with a pure air-cooling mode were analyzed and predicted with the factors affecting the unevenness of temperature field discussed. The results show a significant effect of the cooling flow rate on the temperature rise of the cells for all discharge rates. Average surface temperatures are relatively uniform at lower discharge rate that makes it easier to control the temperature of the pack. Cell temperatures are expected to rise significantly toward the end of discharge and they show non-uniformity at higher discharge rates. Adequate air flow rate of active cooling is required at high discharge rate and high ambient temperature for practical pack thermal management system.

Zhang, Zhuqian; Jia, Li; Zhao, Nan; Yang, Lixin

2011-12-01

298

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

NASA Astrophysics Data System (ADS)

The cooling pond of the Chernobyl nuclear power plant was heavily contaminated as a result of the reactor accident in April 1986. From 1989 to 1993 the cooling pond represented one of the major sources of 90Sr migration from the Chernobyl site to the Dnieper River. Several attempts have been made to contain radioactive contamination within the pond. Overestimation of releases via groundwater pathway and design mistakes led to unsuccessful remedial actions in 1986 and in later periods. In addition, remediation criteria based solely on comparison of contaminant concentrations in groundwater with drinking water standards were not effective from the health risk perspective, because the public was not directly exposed to contaminated groundwater; the exclusion zone surrounding the site acted as an institutional control to prevent public access. In light of recent estimates of low risks due to radionuclide transport outside the exclusion zone, a "no action" approach may represent the most reasonable strategy for the near-term management of the cooling pond.

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

1997-04-01

299

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

PubMed

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

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

1986-09-01

300

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

PubMed Central

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

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

1986-01-01

301

Legionnaires' disease bacteria in power plant cooling systems: downtime report. Final report  

SciTech Connect

Legionnaires' disease bacteria (Legionella) are a normal part of the aquatic community that, when aerosolized, can be pathogenic to man. The downtime study was designed to determine the degree to which Legionella populations are aerosolized during cleaning and maintenance operations in a closed-cycle steam-electric power plant. Both high-volume and impinger air samples were collected prior to and during downtime operations. Emphasis was placed on sampling inside or adjacent to water boxes, condensers, and cooling towers. Control air samples were taken upwind from the plant site. Water and sludge samples were also collected at various locations. In the laboratory, the concentrations of Legionella were determined using the direct fluorescent antibody method. All positive air samples, and other selected air samples, were injected into guinea pigs to detect infectious Legionella. Legionella could be detected in only 12 of the 127 air samples collected. These were predominantly L. pneumophila, serogroups 1-6. In contrast to the air samples, most of the water and sludge samples were positive for Legionella, again predominantly L. pneumophila, serogroups 1-6. The highest Legionella concentrations were found in sludge samples associated with condenser tube cleaning. Among the water samples, the highest Legionella concentrations were found in cooling towers, immediately after the tower basins were cleaned and refilled, and in condenser tubes. Two of the three cooling tower water samples collected prior to downtime operations were infectious for guinea pigs. 16 refs., 4 figs., 11 tabs.

Tyndall, R.L.; Solomon, J.A.; Christensen, S.W.

1985-11-01

302

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

SciTech Connect

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.

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

1981-03-01

303

Thermoeconomic assessment of a multi-engine, multi-heat-pump CCHP (combined cooling, heating and power generation) system – A case study  

Microsoft Academic Search

Design and operation of complex systems for combined cooling, heating and power generation (CCHP) are always a matter of matching performance and demand characteristics of a thermal system set to supply electrical, cooling and heating loads, according to specific usage demands. Equipment selection and operation require the characterization of power, heating and cooling load demands, and their time variation during

P. Roque Díaz; Y. R. Benito; J. A. R. Parise

2010-01-01

304

Legionnaires' Disease Bacterium in power-plant cooling systems: Phase 1. Final report  

SciTech Connect

A survey was undertaken of the distribution, density, viability, and infectivity of Legionnaires' Disease Bacteria (Legionella) in power plant cooling systems. Water samples were collected during each of the four seasons at various locations within each of nine power plants and from ambient waters at each site. Measurements of a number of physical and chemical characteristics were made, and Legionella profiles (density, viability, and infectivity for guinea pigs) were obtained. Legionella were detected in nearly all samples. Water from closed-cycle cooling systems frequently had lower densities of Legionella than the ambient water. Nonetheless, infectious Legionella, as defined by their isolation from inoculated guinea pigs, were significantly more likely to be found in samples from the plant-exposed water of closed-cycle plants than in samples from once-through plants or in ambient samples. A new species (L. oakridgensis) was initially isolated from two of the sites, and it has since been found to have a widespread distribution. Two other organisms found to cause illness in guinea pigs may also be new species. Phase II of the project involves investigating possible cause/effect relationships between physicochemical variables and Legionella. This work may contribute toward eventual control techniques for this pathogen.

Christensen, S.W.; Solomon, J.A.; Gough, S.B.; Tyndall, R.L.; Fliermans, C.B.

1983-06-01

305

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

NASA Astrophysics Data System (ADS)

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

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

2010-06-01

306

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

SciTech Connect

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

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

1994-12-01

307

High-power diode-pumped cryogenically-cooled Yb:CaF2 laser with extremely low quantum defect  

E-print Network

High-power diode-pumped cryogenically-cooled Yb:CaF2 laser with extremely low quantum defect S with Yb:CaF2 operating at cryogenic temperature (77 K) leading to extremely low quantum defects of 1-peak power laser with high repetition rate, very interesting laser development at cryogenic temperature has

Boyer, Edmond

308

Cryogenic engineering and fusion power  

Microsoft Academic Search

In order to reduce the consumption of power for the magnets of a fusion power plant to acceptable proportions, it is necessary that fusion reactors must use either cryogenically cooled or superconducting coils. The cryogenic aspects of reactor design are discussed. It is found that the most difficult cryogenic engineering problems of fusion reactors are mainly those caused by the

C. E. Taylor

1974-01-01

309

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

E-print Network

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

Burger, R.

310

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

SciTech Connect

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

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

1984-09-01

311

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

E-print Network

for energy storage. To achieve this performance, a low-temperature environment is necessary. Energy is stored in a magnet by the flow of direct current in a coil made of superconducting materials. The SSO's coil is submerged in liquid helium (-452?F... Administration system. In that project a superconducling coil was used to provide energy to stabilizc a transmission line. Sl's focus on the benefits of superconducting magnetic energy storage Figure I. SI cryostat in an SSO trailer. 63 ESL-IE-92...

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

312

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

313

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

NASA Astrophysics Data System (ADS)

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

Larionov, A. V.

2006-05-01

314

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

NASA Astrophysics Data System (ADS)

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

Tamm, Gunnar Olavi

315

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

SciTech Connect

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

Daniel S. Wendt; Greg L. Mines

2010-09-01

316

Numerical simulation of heat transfer performance of an air-cooled steam condenser in a thermal power plant  

Microsoft Academic Search

Numerical simulation of the thermal-flow characteristics and heat transfer performance is made of an air-cooled steam condenser\\u000a (ACSC) in a thermal power plant by considering the effects of ambient wind speed and direction, air-cooled platform height,\\u000a location of the main factory building and terrain condition. A simplified physical model of the ACSC combined with the measured\\u000a data as input parameters

Xiufeng Gao; Chengwei Zhang; Jinjia Wei; Bo Yu

2009-01-01

317

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

SciTech Connect

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

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

2011-07-24

318

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

Microsoft Academic Search

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

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

2002-01-01

319

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

Microsoft Academic Search

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.

Energetics

2000-01-01

320

Legionnaires' Disease Bacteria in power plant cooling systems: downtime report. Final report  

SciTech Connect

Legionnaires' Disease Bacteria (Legionella) are a normal part of the aquatic community that, when aerosolized, can be pathogenic to man. The downtime study was designed to determine the degree to which Legionella populations are aerosolized during cleaning and maintenance operations in a closed-cycle steam-electric power plant. Both high-volume and impinger air samples were collected prior to and during downtime operations. Emphasis was placed on sampling inside or adjacent to water boxes, condensers, and cooling towers. Control air samples were taken upwind from the plant site. Water and sludge samples were also collected at various locations. In the laboratory, the concentrations of Groups A, B, and C Legionella were determined using the direct fluorescent antibody method. All positive air samples, and other selected air samples, were injected into guinea pigs to detect infectious Legionella. Legionella could be detected in only 12 of the 126 air samples collected. These were predominantly Group A Legionella (L. pneumophila, serogroups 1 to 6). All 12 positive samples had been collected in the vicinity of water boxes, condensers, detention ponds, and cooling towers during downtime operations where aerosolization of Legionella populations would be expected. None of the air samples yielded infectious Legionella when injected into guinea pigs. Detection of Legionella in air samples taken during downtime was significantly more likely than detection during normal operating conditions (p <0.01). 13 refs., 4 figs., 10 tabs.

Tyndall, R.L.; Solomon, J.A.; Christensen, S.W.

1985-04-01

321

Steam generator tube performance: world experience with water-cooled nuclear power reactors during 1979  

SciTech Connect

The performance of steam generator tubes in water-cooled nuclear power reactors is reviewed for 1979. Tube failures occurred at 38 of the 93 reactors surveyed. The causes of these failures and the procedures designed to deal with them are described. The defect rate, although higher than that in 1978, was still lower than the rates of the two previous years. Methods being employed to detect defects include the increased use of multifrequency eddy-current testing and a trend to full-length inspection of all tubes. To reduce the incidence of tube failure by corrosion, plant operators are turning to full-flow condensate demineralization and more leak-resistant condenser tubes. 10 tables.

Tatone, O.S.; Pathania, R.S.

1981-09-01

322

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

NASA Astrophysics Data System (ADS)

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

Lizon-A-Lugrin, Laure

323

Hybrid superconducting magnetic suspensions  

SciTech Connect

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

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

1996-07-01

324

Superconducting magnet  

NASA Technical Reports Server (NTRS)

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

1985-01-01

325

PREFACE: Superconducting materials Superconducting materials  

NASA Astrophysics Data System (ADS)

The discovery of superconductivity in 1911 was a great milestone in condensed matter physics. This discovery has resulted in an enormous amount of research activity. Collaboration among chemists and physicists, as well as experimentalists and theoreticians has given rise to very rich physics with significant potential applications ranging from electric power transmission to quantum information. Several superconducting materials have been synthesized. Crucial progress was made in 1987 with the discovery of high temperature superconductivity in copper-based compounds (cuprates) which have revealed new fascinating properties. Innovative theoretical tools have been developed to understand the striking features of cuprates which have remained for three decades the 'blue-eyed boy' for researchers in superconductor physics. The history of superconducting materials has been notably marked by the discovery of other compounds, particularly organic superconductors which despite their low critical temperature continue to attract great interest regarding their exotic properties. Last but not least, the recent observation of superconductivity in iron-based materials (pnictides) has renewed hope in reaching room temperature superconductivity. However, despite intense worldwide studies, several features related to this phenomenon remain unveiled. One of the fundamental key questions is the mechanism by which superconductivity takes place. Superconductors continue to hide their 'secret garden'. The new trends in the physics of superconductivity have been one of the two basic topics of the International Conference on Conducting Materials (ICoCoM2010) held in Sousse,Tunisia on 3-7 November 2010 and organized by the Tunisian Physical Society. The conference was a nice opportunity to bring together participants from multidisciplinary domains in the physics of superconductivity. This special section contains papers submitted by participants who gave an oral contribution at ICoCoM2010 and by invited authors selected by the editor. We are grateful to IUPAP, ICTP and the European Office of Aerospace Research and Development, Air Force Office of Scientific Research, United States Air Force Laboratory. We would like to acknowledge the authors for their careful work, and finally we thank Dr L Smith the publisher of Journal of Physics: Condensed Matter for her patience and help. Superconducting materials contents Raman spectrum in the pseudogap phase of the underdoped cuprates: effect of phase coherence and the signature of the KT-type superconducting transitionTao Li and Haijun Liao Pressure effects on Dirac fermions in ?-(BEDT-TTF)2I3Takahiro Himura, Takao Morinari and Takami Tohyama Effect of Zn doping in hole-type 1111 phase (Pr, Sr)FeAsOXiao Lin, Chenyi Shen, Chen Lv, Jianjian Miao, Hao Tan, Guanghan Cao and Zhu-An Xu Superconductivity and ferromagnetism in EuFe2(As1 - xPx)2*Guanghan Cao, Shenggao Xu, Zhi Ren, Shuai Jiang, Chunmu Feng and Zhu'an Xu OInhomogeneous superconductivity in organic conductors: the role of disorder and magnetic fieldS Haddad, S Charfi-Kaddour and J-P Pouget

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

2011-11-01

326

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

SciTech Connect

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

Hammons, L.; Hahn, H.

2011-03-28

327

Electric motors using superconducting materials applied to power generating station equipment  

SciTech Connect

The application of high temperature superconductors (HTSC) to electric motors is discussed. A synchronous motor with an HTSC field winding is described, and its steady state performance and economic viability is summarized. Large HTSC synchronous motors are predicted to be one-half the size and have one-half the losses of comparably-rated conventional motors. Test rig and prototype motors used for developing design techniques for air core superconducting synchronous motors are described, and test results are discussed. HTSC coil testing techniques and results are discussed. These test results indicate that HTSC wire performance is rapidly improving toward the required performance for large HTSC motors. Finally, a design and analysis study of a 5000-horsepower motor is summarized. overall, this report describes an ongoing comprehensive superconducting motor research program that is using state-of-the-art HTSC coils to build prototype motors and developing designs for future large HTSC motors.

Jordan, H.E.; Edick, J.D.; Schiferl, R.F. (Reliance Electric Co., Cleveland, OH (United States))

1992-09-01

328

Power Tests of a String of Magnets Comprising a Full Cell of the Superconducting Super Collider  

SciTech Connect

In this paper we describe the operation and testing of a string of magnets comprising a full cell of the Superconducting Super Collider (SSC). The full cell configuration composed of ten dipoles, two quadrupoles, and three spool pieces is the longest SSC magnet string ever tested. Although the tests of the full cell were undertaken after the SSC project was marked for termination, their completion was deemed necessary and useful to future efforts at other accelerator laboratories utilizing Superconducting magnets. The focus of this work is on the electrical and cryogenic performance of the string components and the quench protection system with an emphasis on solving some of the questions concerning electrical performance raised during the previous two experimental runs involving a half cell configuration.

Burgett, W.; Cromer, L.; Haenni, D.; Hentges, M.; Jaffrey, T.; Kraushaar, P.; Levin, M.; Mulholland, G.; Richter, D.; Robinson, W.; Weisend II, J.; Zapotek, J.

1995-06-28

329

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

PubMed Central

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

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

2013-01-01

330

THE CHANDRA DEEP PROTOCLUSTER SURVEY: Ly{alpha} BLOBS ARE POWERED BY HEATING, NOT COOLING  

SciTech Connect

We present the results of a 400 ks Chandra survey of 29 extended Ly{alpha} emitting nebulae (Ly{alpha} Blobs, LABs) in the z = 3.09 protocluster in the SS A22 field. We detect luminous X-ray counterparts in five LABs, implying a large fraction of active galactic nuclei (AGN) in LABs, f{sub AGN} = 17{sup +12}{sub -7}% down to L{sub 2-32keV} {approx} 10{sup 44} erg s{sup -1}. All of the AGN appear to be heavily obscured, with spectral indices implying obscuring column densities of N{sub H} > 10{sup 23} cm{sup -2}. The AGN fraction should be considered a lower limit, since several more LABs not detected with Chandra show AGN signatures in their mid-infrared (mid-IR) emission. We show that the UV luminosities of the AGN are easily capable of powering the extended Ly{alpha} emission via photoionization alone. When combined with the UV flux from a starburst component, and energy deposited by mechanical feedback, we demonstrate that 'heating' by a central source, rather than gravitational cooling is the most likely power source of LABs. We argue that all LABs could be powered in this manner, but that the luminous host galaxies are often just below the sensitivity limits of current instrumentation, or are heavily obscured. No individual LABs show evidence for extended X-ray emission, and a stack equivalent to a {approx}>9 Ms exposure of an average LAB also yields no statistical detection of a diffuse X-ray component. The resulting diffuse X-ray/Ly{alpha} luminosity limit implies there is no hot (T {approx}> 10{sup 7} K) gas component in these halos, and also rules out inverse Compton scattering of cosmic microwave background photons, or local far-IR photons, as a viable power source for LABs.

Geach, J. E.; Alexander, D. M.; Lehmer, B. D.; Matsuda, Y. [Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Smail, Ian; Bower, R. G. [Institute for Computational Cosmology, Department of Physics, Durham University, South Road, Durham DH1 3LE (United Kingdom); Chapman, S. C. [Institute of Astronomy, Madingley Road, Cambridge, CB3 0HA (United Kingdom); Scharf, C. A.; Bauer, F. E.; Basu-Zych, A. [Columbia Astrophysics Laboratory, Columbia University, Pupin Laboratories, 550 West 120th Street, Room 1418, New York, NY 10027 (United States); Ivison, R. J. [SUPA, Institute for Astronomy, Royal Observatory of Edinburgh, Blackford Hill, Edinburgh, EH9 3HJ (United Kingdom); Volonteri, M. [Department of Astronomy, University of Michigan, Ann Arbor, MI (United States); Yamada, T. [National Astronomical Observatory of Japan, Tokyo 181-8588 (Japan); Blain, A. W. [Department of Astronomy, California Institute of Technology, MC 105-24, 1200, East California Boulevard, Pasadena, CA 91125 (United States)], E-mail: j.e.geach@durham.ac.uk

2009-07-20

331

Summary results of an assessment of research projects in the superconductivity for electric power systems program  

SciTech Connect

The Office of Program Analysis undertook an assessment of 37 research projects sponsored by the High Temperature Superconductivity Program. This report summarizes the results of the review. Rating factors included scientific and technical merit, mission relevance, appropriateness and level of innovation, quality of project team, productivity, and probable impact on the program`s mission. Some research needs and opportunities are described that were identified by the reviewers in the areas of wire development, deposited film technology, and systems development.

NONE

1992-10-01

332

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. ...

333

High-Temperature Superconductivity  

NASA Astrophysics Data System (ADS)

A general review on high-temperature superconductivity was made. After prehistoric view and the process of discovery were stated, the special features of high-temperature superconductors were explained from the materials side and the physical properties side. The present status on applications of high-temperature superconductors were explained on superconducting tapes, electric power cables, magnets for maglev trains, electric motors, superconducting quantum interference device (SQUID) and single flux quantum (SFQ) devices and circuits.

Tanaka, Shoji

2006-12-01

334

Analysis of the accident in the second power-generating unit of the Chernobyl nuclear power plant caused by inadequate makeup of the reactor cooling loop  

SciTech Connect

The accident in the second power-generating unit of the Chernobyl nuclear power plant on October 11, 1991 was the result of unauthorized connection of the TG-4 turbogenerator, which was shut down for repairs, into the grid (in the off-design asynchronous engine mode), and this resulted in a serious fire in the machine room and subsequent failure of systems which are important for safety and which ensure the design mode of reactor cooling: These were primarily failures of the feed and emergency feed pumps and failure of the BRU-B control valve, which regulates steam release during cooling.

Vasil`chenko, V.N.; Kramerov, A.Ya.; Mikhailov, D.A. [and others

1995-10-01

335

Organic Fluids and Passive Cooling in a Supercritical Rankine Cycle for Power Generation from Low Grade Heat Sources  

NASA Astrophysics Data System (ADS)

Low grade heat sources have a large amount of thermal energy content. Due to low temperature, the conventional power generation technologies result in lower efficiency and hence cannot be used. In order to efficiently generate power, alternate methods need to be used. In this study, a supercritical organic Rankine cycle was used for heat source temperatures varying from 125°C to 200°C. Organic refrigerants with zero ozone depletion potential and their mixtures were selected as working fluid for this study while the cooling water temperature was changed from 10-25°C. Operating pressure of the cycle has been optimized for each fluid at every heat source temperature to obtain the highest thermal efficiency. Energy and exergy efficiencies of the thermodynamic cycle have been obtained as a function of heat source temperature. Efficiency of a thermodynamic cycle depends significantly on the sink temperature. At areas where water cooling is not available and ambient air temperature is high, efficient power generation from low grade heat sources may be a challenge. Use of passive cooling systems coupled with the condenser was studied, so that lower sink temperatures could be obtained. Underground tunnels, buried at a depth of few meters, were used as earth-air-heat-exchanger (EAHE) through which hot ambient air was passed. It was observed that the air temperature could be lowered by 5-10°C in the EAHE. Vertical pipes were used to lower the temperature of water by 5°C by passing it underground. Nocturnal cooling of stored water has been studied that can be used to cool the working fluid in the thermodynamic cycle. It was observed that the water temperature can be lowered by 10-20°C during the night when it is allowed to cool. The amount of water lost was calculated and was found to be approximately 0.1% over 10 days. The different passive cooling systems were studied separately and their effects on the efficiency of the thermodynamic cycle were investigated. They were then combined into a novel condenser design that uses passive cooling technology to cool the working fluid that was selected in the first part of the study. It was observed that the efficiency of the cycle improved by 2-2.5% when passive cooling system was used.

Vidhi, Rachana

336

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...

337

Modeling of the filling and cooling processes of hot fuel mains in Liquid Fuel Rocket Power Plant (LFRPP)  

Microsoft Academic Search

A mathematical model of heat and mass exchange processes during filling and cooling of hot fuel mains of the Liquid Fuel Rocket Power Plant (LFRPP), which allows to define a mass consumption and distribution of two-phase flow parameters by the length of pipeline. Results of calculations are compared with experimental data, taken during filling of the main with a supply

V. F. Prisnyakov; V. V. Pokrishkin; V. N. Serebryansky

1992-01-01

338

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

NASA Astrophysics Data System (ADS)

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

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

2011-03-01

339

Preliminary analysis of problem of determining experimental performance of air-cooled turbine III : methods for determining power and efficiency  

NASA Technical Reports Server (NTRS)

Suggested formula are given for determining air-cooled turbine-performance characteristics, such as power and efficiency, as functions of certain parameters. These functions, generally being unknown, are determined from experimental data obtained from specific investigations. Special plotting methods for isolating the effect of each parameter are outlined.

Ellerbrock, Herman H , Jr; Ziemer, Robert R

1950-01-01

340

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...

341

Concept of an advanced power-generating unit with a BN1200 sodium-cooled fast reactor  

Microsoft Academic Search

The status of work on the development of a 1200 MW sodium-cooled reactor facility for serial construction is presented. The\\u000a general characteristics of the facility and the power-generating unit as well as the objectives which must be attained as\\u000a a result of the design are presented. The design of the power-generating group is based on solutions some of which have

V. I. Rachkov; V. M. Poplavskii; A. M. Tsibulya; Yu. E. Bagdasarov; B. A. Vasiliev; Yu. L. Kamanin; S. L. Osipov; N. G. Kuzavkov; V. N. Ershov; M. R. Ashirmetov

2010-01-01

342

Superconducting wire with improved strain characteristics  

DOEpatents

A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improve the strain characteristics of the wire.

Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (East Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

1982-01-01

343

Superconducting wire with improved strain characteristics  

DOEpatents

A superconducting wire comprising a superconducting filament and a beryllium strengthened bronze matrix in which the addition of beryllium to the matrix permits a low volume matrix to exhibit reduced elastic deformation after heat treating which increases the compression of the superconducting filament on cooling and thereby improves the strain characteristics of the wire.

Luhman, Thomas (Westhampton Beach, NY); Klamut, Carl J. (E. Patchogue, NY); Suenaga, Masaki (Bellport, NY); Welch, David (Stony Brook, NY)

1982-01-01

344

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

SciTech Connect

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.

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

345

Development of superconductive magnets  

NASA Technical Reports Server (NTRS)

Survey of superconductive magnets considers - stabilization problems, advances in materials and their uses, and design evolution. Uses of superconducting magnets in particle accelerators and bubble chambers, as well as possible applications in magnetohydrodynamic and thermonuclear power generation and levitation are discussed.

Laurence, J. C.

1970-01-01

346

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

NASA Astrophysics Data System (ADS)

Thermoelectric power plants require large volumes of water for cooling, which can introduce drought vulnerability and compete with other water needs. Alternative cooling technologies, such as cooling towers and hybrid wet-dry or dry cooling, present opportunities to reduce water diversions. This case study uses a custom, geographically resolved river basin-based model for eleven river basins in the state of Texas (the Brazos and San Jacinto-Brazos, Colorado and Colorado-Brazos, Cypress, Neches, Nueces, Red, Sabine, San Jacinto, and Trinity River basins), focusing on the Brazos River basin, to analyze water availability during drought. We utilized two existing water availability models for our analysis: (1) the full execution of water rights—a scenario where each water rights holder diverts the full permitted volume with zero return flow, and (2) current conditions—a scenario reflecting actual diversions with associated return flows. Our model results show that switching the cooling technologies at power plants in the eleven analyzed river basins to less water-intensive alternative designs can potentially reduce annual water diversions by 247-703 million m3—enough water for 1.3-3.6 million people annually. We consider these results in a geographic context using geographic information system tools and then analyze volume reliability, which is a policymaker's metric that indicates the percentage of total demand actually supplied over a given period. This geographic and volume reliability analysis serves as a measure of drought susceptibility in response to changes in thermoelectric cooling technologies. While these water diversion savings do not alleviate all reliability concerns, the additional streamflow from the use of dry cooling alleviates drought concerns for some municipal water rights holders and might also be sufficient to uphold instream flow requirements for important bays and estuaries on the Texas Gulf coast.

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

2011-07-01

347

Micro Cooling, Heating, and Power (Micro-CHP) and Bio-Fuel Center, Mississippi State University  

SciTech Connect

Initially, most micro-CHP systems will likely be designed as constant-power output or base-load systems. This implies that at some point the power requirement will not be met, or that the requirement will be exceeded. Realistically, both cases will occur within a 24-hour period. For example, in the United States, the base electrical load for the average home is approximately 2 kW while the peak electrical demand is slightly over 4 kW. If a 3 kWe micro- CHP system were installed in this situation, part of the time more energy will be provided than could be used and for a portion of the time more energy will be required than could be provided. Jalalzadeh-Azar [6] investigated this situation and presented a comparison of electrical- and thermal-load-following CHP systems. In his investigation he included in a parametric analysis addressing the influence of the subsystem efficiencies on the total primary energy consumption as well as an economic analysis of these systems. He found that an increase in the efficiencies of the on-site power generation and electrical equipment reduced the total monthly import of electricity. A methodology for calculating performance characteristics of different micro-CHP system components will be introduced in this article. Thermodynamic cycles are used to model each individual prime mover. The prime movers modeled in this article are a spark-ignition internal combustion engine (Otto cycle) and a diesel engine (Diesel cycle). Calculations for heat exchanger, absorption chiller, and boiler modeling are also presented. The individual component models are then linked together to calculate total system performance values. Performance characteristics that will be observed for each system include maximum fuel flow rate, total monthly fuel consumption, and system energy (electrical, thermal, and total) efficiencies. Also, whether or not both the required electrical and thermal loads can sufficiently be accounted for within the system specifications is observed. Case study data for various micro-CHP system configurations have been discussed and compared. Comparisons are made of the different prime mover/fuel combinations. Also, micro- CHP monthly energy cost results are compared for each system configuration to conventional monthly utility costs for equivalent monthly building power, heating, and cooling requirements.

Louay Chamra

2008-09-26

348

Powering the intra-cluster filaments in cool-core clusters of galaxies  

NASA Astrophysics Data System (ADS)

The first radio surveys of the sky discovered that some large clusters of galaxies contained powerful sources of synchrotron emission. Optical images showed that long linear filaments with bizarre emission-line spectra permeated the intra-cluster medium. Recent observations in the infrared and radio show that these filaments have very strong emission lines of molecular hydrogen and carbon monoxide. The mass of molecular material is quite large, the gas is quite warm, and the filaments have not formed stars despite their ~Gyr age. I will discuss the general astrophysical context of large clusters of galaxies and how large masses of molecular gas can be heated to produce what we observe. The unique properties of the filaments are a result of the unique environment. Magnetically confined molecular filaments are surrounded by the hot intra-cluster medium. Thermal particles with keV energies enter atomic and molecular regions and produce a shower of secondary nonthermal electrons. These secondaries collisionally heat, excite, dissociate, and ionize the cool gas. While ionization is dominated by these secondary particles, recombination is controlled by charge exchange, which produces the unusual optical emission line spectrum. I will describe some of the physical processes that are unique to this environment and outline some of the atomic physics issues.

Ferland, Gary J.

2012-05-01

349

Thermal ecology of Naegleria fowleri from a power plant cooling reservoir  

SciTech Connect

The pathogenic, free-living amoeba Naegleria fowleri is the causative agent of human primary amebic meningoencephalitis. N. fowleri has been isolated from thermally elevated aquatic environments worldwide, but temperature factors associated with occurrence of the amoeba remain undefined. In this study, a newly created cooling reservoir (Clinton Lake, Illinois) was surveyed for Naegleria spp. before and after thermal additions from a nuclear power plant. Water and sediment samples were collected from heated and unheated arms of the reservoir and analyzed for the presence of thermophilic Naegleria spp. and pathogenic N. fowleri. Amoebae were identified by morphology, in vitro cultivation, temperature tolerance, mouse pathogenicity assay, and DNA restriction fragment length analysis. N. fowleri was isolated from the thermally elevated arm but not from the ambient-temperature arm of the reservoir. The probability of isolating thermophilic Naegleria and pathogenic N. fowleri increased significantly with temperature. Repetitive DNA restriction fragment profiles of the N. fowleri Clinton Lake isolates and a known N. fowleri strain of human origin were homogeneous.

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

1990-07-01

350

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

NASA Astrophysics Data System (ADS)

Low cost magnetocaloric nanomaterials have attracted considerable attention for energy efficient applications. We report a very high relative cooling power (RCP) in a study of the magnetocaloric effect in quenched FeNiB nanoparticles. RCP increases from 89.8 to 640 J kg-1 for a field change of 1 and 5 T, respectively, these values are the largest for rare earth free iron based magnetocaloric nanomaterials. To investigate the magnetocaloric behavior around the Curie temperature (TC), the critical behavior of these quenched nanoparticles was studied. Detailed analysis of the magnetic phase transition using the modified Arrott plot, Kouvel-Fisher method, and critical isotherm plots yields critical exponents of ? = 0.364, ? = 1.319, ? = 4.623, and ? = -0.055, which are close to the theoretical exponents obtained from the 3D-Heisenberg model. Our results indicate that these FeNiB nanoparticles are potential candidates for magnetocaloric fluid based heat pumps and low grade waste heat recovery.

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

2014-10-01

351

Energy-saving method and apparatus for automatically controlling cooling pumps of steam power plants  

SciTech Connect

This patent describes an electric power generating plant of the type which employs steam to generate electricity, using a condenser which is cooled by being supplied with ambient water whose temperature (T) is subject to changes over time, and which water may be supplied to the condenser by a number of pumps operated in parallel, each pump driven by its own motor. The plant is constructed to operate with over a range between a minimum and a maximum number of such pumps. The method of more optionally operating the plant is described comprising: (a) recording a set of reference values for at least temperature and load (Tr,Fr) for the number of pumps in initial operation; (b) monitoring the current temperature and load (Ty, Fy) and, if either of these change significantly (increasing or decreasing), if not already at the end of the range in that direction, changing the number of pumps in steps, in the same direction of change (increasing or decreasing), and (c) calculating the net gain or loss in overall energy efficiency of each new pump added, until the end of the range is reached or a most efficient number of pumps is determined, and then operating at that number, while updating the reference values (Tr,Fr) to its values and returning to step (b).

Julovich, G.C.

1987-02-17

352

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

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

353

Optimization of electron cooling by SIN tunnel junctions  

NASA Astrophysics Data System (ADS)

We report on the optimization of electron cooling by SIN tunnel junctions due to the advanced geometry of superconducting electrodes and very effective normal metal traps for more efficient removal of quasiparticles at temperatures from 25 to 500 mK. The maximum decrease in electron temperature of about 200 mK has been observed at bath temperatures 300-350 mK. We used four-junction geometry with Al-AlOx-Cr/Cu tunnel junctions and Au traps. Efficient electron cooling was realized due to the improved geometry of the cooling tunnel junctions (quadrant shape of the superconducting electrode) and optimized Au traps just near the junctions ({\\approx }0.5~\\micmu {\\mathrm {m}} ) to reduce reabsorption of quasiparticles after removing them from normal metal. The maximum cooling effect was increased from a temperature drop of d T = -56 mK (ordinary cross geometry) to -130 mK (improved geometry of superconducting electrodes) and to d T = -200 mK (improved geometry of superconducting electrodes and effective Au traps). The heating peak (instead of cooling) near the zero voltage across cooling junctions has been observed in practice for all samples at temperatures below 150 mK. For higher cooling voltages close to the superconducting gap, the heating was converted to cooling with decreased amplitude. The leakage resistance of the tunnel junctions gives a reasonable explanation of the heating peak. The phonon reabsorption due to the recombination of quasiparticles in superconducting electrodes gives an additional improvement in the theoretical fitting but could not explain the heating peak. An anomalous zero-bias resistance peak has been observed for all tested structures. The peak is explained by Coulomb blockade of tunnelling in transistor-type structures with relatively small tunnel junctions. The work on electron cooling is devoted to the development of a cold-electron bolometer (CEB) with capacitive coupling by SIN tunnel junctions to the antenna for sensitive detection in the terahertz region. Direct electron cooling of an absorber plays a crucial role in supersensitive detection in the presence of a realistic background power load.

Kuzmin, L.; Agulo, I.; Fominsky, M.; Savin, A.; Tarasov, M.

2004-05-01

354

Storing carbon dioxide in saline formations : analyzing extracted water treatment and use for power plant cooling.  

SciTech Connect

In an effort to address the potential to scale up of carbon dioxide (CO{sub 2}) capture and sequestration in the United States saline formations, an assessment model is being developed using a national database and modeling tool. This tool builds upon the existing NatCarb database as well as supplemental geological information to address scale up potential for carbon dioxide storage within these formations. The focus of the assessment model is to specifically address the question, 'Where are opportunities to couple CO{sub 2} storage and extracted water use for existing and expanding power plants, and what are the economic impacts of these systems relative to traditional power systems?' Initial findings indicate that approximately less than 20% of all the existing complete saline formation well data points meet the working criteria for combined CO{sub 2} storage and extracted water treatment systems. The initial results of the analysis indicate that less than 20% of all the existing complete saline formation well data may meet the working depth, salinity and formation intersecting criteria. These results were taken from examining updated NatCarb data. This finding, while just an initial result, suggests that the combined use of saline formations for CO{sub 2} storage and extracted water use may be limited by the selection criteria chosen. A second preliminary finding of the analysis suggests that some of the necessary data required for this analysis is not present in all of the NatCarb records. This type of analysis represents the beginning of the larger, in depth study for all existing coal and natural gas power plants and saline formations in the U.S. for the purpose of potential CO{sub 2} storage and water reuse for supplemental cooling. Additionally, this allows for potential policy insight when understanding the difficult nature of combined potential institutional (regulatory) and physical (engineered geological sequestration and extracted water system) constraints across the United States. Finally, a representative scenario for a 1,800 MW subcritical coal fired power plant (amongst other types including supercritical coal, integrated gasification combined cycle, natural gas turbine and natural gas combined cycle) can look to existing and new carbon capture, transportation, compression and sequestration technologies along with a suite of extracting and treating technologies for water to assess the system's overall physical and economic viability. Thus, this particular plant, with 90% capture, will reduce the net emissions of CO{sub 2} (original less the amount of energy and hence CO{sub 2} emissions required to power the carbon capture water treatment systems) less than 90%, and its water demands will increase by approximately 50%. These systems may increase the plant's LCOE by approximately 50% or more. This representative example suggests that scaling up these CO{sub 2} capture and sequestration technologies to many plants throughout the country could increase the water demands substantially at the regional, and possibly national level. These scenarios for all power plants and saline formations throughout U.S. can incorporate new information as it becomes available for potential new plant build out planning.

Dwyer, Brian P.; Heath, Jason E.; Borns, David James; Dewers, Thomas A.; Kobos, Peter Holmes; Roach, Jesse D.; McNemar, Andrea; Krumhansl, James Lee; Klise, Geoffrey T.

2010-10-01

355

Cooling power enhancement for 2-D and 3-D CPC sky radiators  

Microsoft Academic Search

This work describes the experimental results of the newly proposed 2-D and 3-D sky radiators. In order to enhance the performance of sky radiation cooling, the authors have proposed a compound parabolic concentrating (CPC) sky radiator with 2-D geometry and demonstrated that the CPC sky radiator has a greater cooling performance than the conventional flat plate one. In the present

Takeo S. SAITOH; Jun TAKAHASHI

2002-01-01

356

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

Microsoft Academic Search

This report has been prepared for the Department of Energy, Office of Nuclear Energy (DOE-NE), for the purpose of providing a status report on the challenges and opportunities facing the U.S. commercial nuclear energy industry in the area of plant cooling water supply. The report was prompted in part by recent Second Circuit and Supreme Court decisions regarding cooling water

Gary Vine

2010-01-01

357

Reuse of Treated Internal or External Wastewaters in the Cooling Systems of Coal-Based Thermoelectric Power Plants  

SciTech Connect

This study evaluated the feasibility of using three impaired waters - secondary treated municipal wastewater, passively treated abandoned mine drainage (AMD), and effluent from ash sedimentation ponds at power plants - for use as makeup water in recirculating cooling water systems at thermoelectric power plants. The evaluation included assessment of water availability based on proximity and relevant regulations as well as feasibility of managing cooling water quality with traditional chemical management schemes. Options for chemical treatment to prevent corrosion, scaling, and biofouling were identified through review of current practices, and were tested at bench and pilot-scale. Secondary treated wastewater is the most widely available impaired water that can serve as a reliable source of cooling water makeup. There are no federal regulations specifically related to impaired water reuse but a number of states have introduced regulations with primary focus on water aerosol 'drift' emitted from cooling towers, which has the potential to contain elevated concentrations of chemicals and microorganisms and may pose health risk to the public. It was determined that corrosion, scaling, and biofouling can be controlled adequately in cooling systems using secondary treated municipal wastewater at 4-6 cycles of concentration. The high concentration of dissolved solids in treated AMD rendered difficulties in scaling inhibition and requires more comprehensive pretreatment and scaling controls. Addition of appropriate chemicals can adequately control corrosion, scaling and biological growth in ash transport water, which typically has the best water quality among the three waters evaluated in this study. The high TDS in the blowdown from pilot-scale testing units with both passively treated mine drainage and secondary treated municipal wastewater and the high sulfate concentration in the mine drainage blowdown water were identified as the main challenges for blowdown disposal. Membrane treatment (nanofiltration or reverse osmosis) can be employed to reduce TDS and sulfate concentrations to acceptable levels for reuse of the blowdown in the cooling systems as makeup water.

Radisav Vidic; David Dzombak; Ming-Kai Hsieh; Heng Li; Shih-Hsiang Chien; Yinghua Feng; Indranil Chowdhury; Jason Monnell

2009-06-30

358

A superconducting pendulum as a thermodynamic machine  

NASA Astrophysics Data System (ADS)

We present a thermodynamic machine based on the superconductivity of a YBaCuO high-temperature superconducting bulk ceramic sample cooled with liquid nitrogen. The machine is a simple pendulum where the superconducting sample periodically changes its normal and superconducting phase by swinging between two heat reservoirs in an inhomogeneous magnetic field. The basic parameters, the characteristics of the superconducting pendulum and some technical details are reported. The working principle is explained in a simple way based on thermodynamics, including the elementary macroscopic magnetic properties of superconductivity. The limitations of this explanation are outlined.

Hegman, N.; Vad, K.; Mészáros, S.; Lindenmájer, J.

1998-05-01

359

Impact of drought on U.S. steam electric power plant cooling water intakes and related water resource management issues.  

SciTech Connect

This report was funded by the U.S. Department of Energy's (DOE's) National Energy Technology Laboratory (NETL) Existing Plants Research Program, which has an energy-water research effort that focuses on water use at power plants. This study complements their overall research effort by evaluating water availability at power plants under drought conditions. While there are a number of competing demands on water uses, particularly during drought conditions, this report focuses solely on impacts to the U.S. steam electric power plant fleet. Included are both fossil-fuel and nuclear power plants. One plant examined also uses biomass as a fuel. The purpose of this project is to estimate the impact on generation capacity of a drop in water level at U.S. steam electric power plants due to climatic or other conditions. While, as indicated above, the temperature of the water can impact decisions to halt or curtail power plant operations, this report specifically examines impacts as a result of a drop in water levels below power plant submerged cooling water intakes. Impacts due to the combined effects of excessive temperatures of the returned cooling water and elevated temperatures of receiving waters (due to high ambient temperatures associated with drought) may be examined in a subsequent study. For this study, the sources of cooling water used by the U.S. steam electric power plant fleet were examined. This effort entailed development of a database of power plants and cooling water intake locations and depths for those plants that use surface water as a source of cooling water. Development of the database and its general characteristics are described in Chapter 2 of this report. Examination of the database gives an indication of how low water levels can drop before cooling water intakes cease to function. Water level drops are evaluated against a number of different power plant characteristics, such as the nature of the water source (river vs. lake or reservoir) and type of plant (nuclear vs. fossil fuel). This is accomplished in Chapter 3. In Chapter 4, the nature of any compacts or agreements that give priority to users (i.e., which users must stop withdrawing water first) is examined. This is examined on a regional or watershed basis, specifically for western water rights, and also as a function of federal and state water management programs. Chapter 5 presents the findings and conclusions of this study. In addition to the above, a related intent of this study is to conduct preliminary modeling of how lowered surface water levels could affect generating capacity and other factors at different regional power plants. If utility managers are forced to take some units out of service or reduce plant outputs, the fuel mix at the remaining plants and the resulting carbon dioxide emissions may change. Electricity costs and other factors may also be impacted. Argonne has conducted some modeling based on the information presented in the database described in Chapter 2 of this report. A separate report of the modeling effort has been prepared (Poch et al. 2009). In addition to the U.S. steam electric power plant fleet, this modeling also includes an evaluation of power production of hydroelectric facilities. The focus of this modeling is on those power plants located in the western United States.

Kimmell, T. A.; Veil, J. A.; Environmental Science Division

2009-04-03

360

Development of a hybrid quantum system employing a tunable high-Q superconducting microwave resonator and trapped laser-cooled atoms  

NASA Astrophysics Data System (ADS)

We present progress toward a hybrid quantum system in which microwave quanta stored in a superconducting flux qubit are coupled through a magnetic dipole interaction to laser-trapped atoms. In initial experiments, our goal will be to couple a microfabricated superconducting LC resonator to the 6.835 GHz hyperfine splitting in an ensemble of ^87Rb atoms. By trapping the atoms in the evanescent field of a 500-nm-wide optical fiber, we will seek to place them within 10 micrometers of the chip surface, where they will interact with the near-field of the microwave mode. In previous work we have demonstrated a frequency-tunable superconducting resonator having Q 100,000. [1] Here we will describe improvements in the resonator's design to reduce its sensitivity to absorbed photons, as well as the design of components to position the resonator relative to the optical fiber within a dilution refrigerator.

Hertzberg, Jared; Voigt, K.; Kim, Z.; Hoffman, J.; Grover, J.; Lee, J.; Ravets, S.; Hafezi, M.; Taylor, J.; Choudhary, A.; Anderson, J.; Lobb, C.; Orozco, L.; Rolston, S.; Wellstood, F.

2013-03-01

361

Improved Performance of an Air Cooled Condenser (ACC) Using SPX Wind Guide Technology at Coal-Based Thermoelectric Power Plants  

SciTech Connect

This project added a new airflow enhancement technology to an existing ACC cooling process at a selected coal power plant. Airflow parameters and efficiency improvement for the main plant cooling process using the applied technology were determined and compared with the capabilities of existing systems. The project required significant planning and pre-test execution in order to reach the required Air Cooled Condenser system configuration for evaluation. A host Power Plant ACC system had to be identified, agreement finalized, and addition of the SPX ACC Wind Guide Technology completed on that site. Design of the modification, along with procurement, fabrication, instrumentation, and installation of the new airflow enhancement technology were executed. Baseline and post-modification cooling system data was collected and evaluated. The improvement of ACC thermal performance after SPX wind guide installation was clear. Testing of the improvement indicates there is a 5% improvement in heat transfer coefficient in high wind conditions and 1% improvement at low wind speed. The benefit increased with increasing wind speed. This project was completed on schedule and within budget.

Ken Mortensen

2010-12-31

362

Superconducting solenoid Time schedule  

E-print Network

a superconducting solenoid wound with NbTi conductors of various diameters (1.0-1.2- 1.5 mm). The coil is built flange. The coil will be directly cooled in a helium bath. The initial volume of liquid helium by liquid nitrogen. The surfaces of the helium bath and radiation screen will be covered by stainless steel

Titov, Anatoly

363

Hybrid superconducting magnetic suspensions  

Microsoft Academic Search

Superconductors, especially high Tc ones, are the most attractive materials to design stable and fully passive magnetic suspensions which have to control five degrees of freedom. The hybrid superconducting magnetic suspensions present high performances and a simple cooling mode. They consist of a permanent magnet bearing, stabilized by a suitable magnet-superconductor structure. Several designs are given and compared in terms

P. Tixador; P. Hiebel; Y. Brunet; X. Chaud; P. Gautier-Picard

1996-01-01

364

MULTI-TUBE POWER LEADS TOWER FOR BEPCII IR MAGNETS.  

SciTech Connect

A power lead tower containing the multi-tube power leads is designed and under fabrication for the superconducting IR quadrupole magnets in the Beijing Electron Position Collider Upgrade (BEPCII). The lead tower consists of six pairs of gas-cooled leads for seven superconducting coils at various operating currents. The power lead is designed in a modular fashion, which can be easily applied to suit different operating current. The end copper block of the tube lead has a large cold mass that provide a large time constant in case of cooling flow interruption. A novel cryogenic electrical isolator is used for the leads.

JIA,L.X.; ZHANG,X.B.; WANG,L.; WANG,T.H.; YAO,Z.L.

2004-05-11

365

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

SciTech Connect

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. Produced water is generated nationally as a byproduct of oil and gas production. Seven states generate 90 percent of the produced water in the continental US. About 37 percent of the sources documented in the US Geological Survey's (USGS) Produced Waters Database have a TDS of less than 30,000 mg/l. This is significant because produced water treatment for reuse in power plants was found to be very costly above 30,000 mg/l TDS. For the purposes of this report, produced water treatment was assessed using the technologies evaluated for the San Juan Generating Station (SJGS) in Deliverable 3, Treatment and Disposal Analysis. Also, a methodology was developed to readily estimate capital and operating costs for produced water treatment. Two examples are presented to show how the cost estimating methodology can be used to evaluate the cost of treatment of produced water at power plants close to oil and gas production.

Kent Zammit; Michael N. DiFilippo

2005-01-01

366

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

E-print Network

towers, because of their seeming simplicity, are usually orphans of the facilities operation. We are all aware that cooling towers are the step-children of the chemical process plant, electric power generating station, and refrigeration system..., TX, June 19-20, 1990 Figure S. cellular fill Case History III The Power Generating Plant. The question of rebuilding large capacity exiting cooling towers for industrial power plants to modernize them to provide necessary additional capacity...

Burger, R.

367

On the use of a small-scale two-phase thermosiphon to cool high-power electronics  

Microsoft Academic Search

An experimental and analytical investigation of the steady-state thermal-hydraulic operating characteristics of a small-scale two-phase thermosiphon cooling actual power electronics are presented. Boiling heat transfer coefficients and circulation mass velocities were measured while varying heat load and pressure. Both a plain and augmented riser structure, utilizing micro-fins and reentrant cavities, were simultaneously tested. The boiling heat transfer coefficients increased with

D. S. Schrage

1990-01-01

368

Modeling of Solar-Powered Single-Effect Absorption Cooling System and Supermarket Refrigeration\\/HVAC System  

Microsoft Academic Search

This thesis consists of two different research problems. In the first one, the aim is to model and simulate a solar-powered, single-effect, absorption refrigeration system using a flat-plate solar collector and LiBr-H2O mixture as the working fluid. The cooling capacity and the coefficient of performance of the system are analyzed by varying all independent parameters, namely: evaporator pressure, condenser pressure,

Ammar Bahman

2011-01-01

369

FEASIBILITY OF RECOVERING USEFUL SALTS FROM IRRIGATION WASTEWATER CONCENTRATES PRODUCED BY POWER PLANT COOLING  

EPA Science Inventory

The report evaluates the feasibility of a novel energy-conserving way to recover useful salts (sodium sulfate and calcium sulfate) from concentrated brines by evaporation/crystallization. The concentrated brines examined were cooling tower blowdown from agricultural wastewater an...

370

Modelization and test of a 500 J superconducting pulsed power transformer  

Microsoft Academic Search

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

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

1999-01-01

371

Superconducting light generator for large offshore wind turbines  

NASA Astrophysics Data System (ADS)

Offshore wind market demands higher power rate and reliable turbines in order to optimize capital and operational cost. These requests are difficult to overcome with conventional generator technologies due to a significant weight and cost increase with the scaling up. Thus superconducting materials appears as a prominent solution for wind generators, based on their capacity to held high current densities with very small losses, which permits to efficiently replace copper conductors mainly in the rotor field coils. However the state-of-the-art superconducting generator concepts still seem to be expensive and technically challenging for the marine environment. This paper describes a 10 MW class novel direct drive superconducting generator, based on MgB2 wires and a modular cryogen free cooling system, which has been specifically designed for the offshore wind industry needs.

Sanz, S.; Arlaban, T.; Manzanas, R.; Tropeano, M.; Funke, R.; Ková?, P.; Yang, Y.; Neumann, H.; Mondesert, B.

2014-05-01

372

Superconducting magnet  

DOEpatents

A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

Satti, John A. (Naperville, IL)

1980-01-01

373

Applications of superconducting fault current limiters in electric power transmission systems  

Microsoft Academic Search

The introduction of new generating facilities by independent power producers and increasing load demand can result in fault-current over-duty on existing transmission system protective equipment. Conventional solutions to fault current over-duty such as major substation upgrades, splitting existing substation busses or multiple circuit breaker upgrades could be very expensive and require undesirable extended outages and result in lower power system

Leonard Kovalsky; Xing Yuan; Kasegn Tekletsadik; Albert Keri; Joachim Bock; Frank Breuer

2005-01-01

374

Numerical simulation of heat transfer performance of an air-cooled steam condenser in a thermal power plant  

NASA Astrophysics Data System (ADS)

Numerical simulation of the thermal-flow characteristics and heat transfer performance is made of an air-cooled steam condenser (ACSC) in a thermal power plant by considering the effects of ambient wind speed and direction, air-cooled platform height, location of the main factory building and terrain condition. A simplified physical model of the ACSC combined with the measured data as input parameters is used in the simulation. The wind speed effects on the heat transfer performance and the corresponding steam turbine back pressure for different heights of the air-cooled platform are obtained. It is found that the turbine back pressure (absolute pressure) increases with the increase of wind speed and the decrease of platform height. This is because wind can not only reduce the flowrate in the axial fans, especially at the periphery of the air-cooled platform, due to cross-flow effects, but also cause an air temperature increase at the fan inlet due to hot air recirculation, resulting in the deterioration of the heat transfer performance. The hot air recirculation is found to be the dominant factor because the main factory building is situated on the windward side of the ACSC.

Gao, Xiufeng; Zhang, Chengwei; Wei, Jinjia; Yu, Bo

2009-09-01

375

POWERFUL H{sub 2} LINE COOLING IN STEPHAN's QUINTET. I. MAPPING THE SIGNIFICANT COOLING PATHWAYS IN GROUP-WIDE SHOCKS  

SciTech Connect

We present results from the mid-infrared spectral mapping of Stephan's Quintet using the Spitzer Space Telescope. A 1000 km s{sup -1} collision (t{sub col} = 5 x 10{sup 6} yr) has produced a group-wide shock, and for the first time the large-scale distribution of warm molecular hydrogen emission is revealed, as well as its close association with known shock structures. In the main shock region alone we find 5.0 x 10{sup 8} M{sub sun} of warm H{sub 2} spread over {approx}480 kpc{sup 2} and additionally report the discovery of a second major shock-excited H{sub 2} feature, likely a remnant of previous tidal interactions. This brings the total H{sub 2} line luminosity of the group in excess of 10{sup 42} erg s{sup -1}. In the main shock, the H{sub 2} line luminosity exceeds, by a factor of 3, the X-ray luminosity from the hot shocked gas, confirming that the H{sub 2}-cooling pathway dominates over the X-ray. [Si II]34.82 {mu}m emission, detected at a luminosity of 1/10th of that of the H{sub 2}, appears to trace the group-wide shock closely, and in addition, we detect weak [Fe II]25.99 {mu}m emission from the most X-ray luminous part of the shock. Comparison with shock models reveals that this emission is consistent with regions of fast shocks (100 km s{sup -1} < V{sub s} < 300 km s{sup -1}) experiencing depletion of iron and silicon onto dust grains. Star formation in the shock (as traced via ionic lines, polycyclic aromatic hydrocarbon and dust emission) appears in the intruder galaxy, but most strikingly at either end of the radio shock. The shock ridge itself shows little star formation, consistent with a model in which the tremendous H{sub 2} power is driven by turbulent energy transfer from motions in a post-shocked layer which suppresses star formation. The significance of the molecular hydrogen lines over other measured sources of cooling in fast galaxy-scale shocks may have crucial implications for the cooling of gas in the assembly of the first galaxies.

Cluver, M. E.; Ogle, P.; Reach, W. T. [Spitzer Science Center, IPAC, California Institute of Technology, Pasadena, CA 91125 (United States); Appleton, P. N.; Lu, N.; Xu, C. K. [NASA Herschel Science Center, IPAC, California Institute of Technology, Pasadena, CA 91125 (United States); Boulanger, F.; Guillard, P. [Institute d'Astrophysique Spatiale, Universite Paris Sud 11, Orsay (France); Duc, P.-A. [Laboratoire AIM, CEA/DSM - CNRS - Universite Paris Diderot, DAPNIA/Service d'Astrophysique, CEA/Saclay, F-91191 Gif-sur-Yvette Cedex (France); Rasmussen, J. [Carnegie Observatories, 813 Santa Barbara St., Pasadena, CA 91101 (United States); Smith, J. D. [Department of Physics and Astronomy, Mail Drop 111, University of Toledo, 2801 West Bancroft Street, Toledo, OH 43606 (United States); Tuffs, R. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Yun, M. S., E-mail: mcluver@ipac.caltech.ed [Department of Astronomy, University of Massachusetts, Amherst, MA (United States)

2010-02-10

376

Serious pitting hazard in the raft river 5MW(e) Geothermal Power Plant isobutane cooling loop  

SciTech Connect

The 5MW(e) Dual Boiling Cycle Geothermal Power Plant, hence referred to as the Raft River plant, is being developed for DOE by EG and G, Inc., Idaho Falls, Idaho. This pilot power plant is of the binary concept and utilizes isobutane as the working second fluid. The plant will demonstrate the feasibility of power generation from an intermediate temperature ({approx} 290 F) resource. The plant is schematically diagrammed in Figure 1. During the final design phase and after the major components were specified to be made of carbon steel, and ordered, various conditions forced the power plant design to switch from surface water to geothermal fluid for the condenser cooling loop make-up water. Because the geothermal fluid contains significant concentrations of chlorides and sulfates, about 1000 ppm and 65 ppm respectively, aeration in the cooling tower causes this water to become extremely aggressive, especially in the pitting of carbon steel components. Although essentially all of the condenser cooling loop materials are carbon steel, the isobutane condenser and turbine lube oil cooler are the most vulnerable. These components are tubed with carbon steel tubes of 0.085 and 0.075 inch wall thickness. These two components are extremely leak critical heat exchangers. For example, even a single pit perforation in the isobutane condenser can cause plant shutdown through loss of isobutane. Such a leak also poses an explosion or fire hazard. As isobutane pressure falls, the incursion of cooling water into the isobutane loop could occur, causing damage to anhydrous service seals. Under a DOE contract for geothermal failure analysis, Radian Corporation has made a preliminary investigation of the pitting hazard presented by the aggressive cooling fluid and the corrosion inhibition treatment that has thus far been proposed. This report documents Radian's understanding of the present situation and the results of its investigation on possible mitigation of this hazard. Finally, various conclusions and recommendations are made that may, if pursued, lead to a satisfactory solution that will avert a certain early prolonged plant shutdown due to failure of the thin walled isobutane and turbine lube oil cooler tubes.

Ellis, Peter F.

1980-02-25

377

Technical and economic assessment of the use of ammonia expanders for energy recovery in air-cooled power plants  

SciTech Connect

Binary cycle power plants have been the subject of much discussion among engineers and scientists for nearly 100 years. Current economic and environmental concerns have stimulated new interest and research. Ammonia has been recommended by other studies as the leading contender for use as simply the heat rejection medium in an air-cooled power plant. This study investigates the technical feasibility and economic potential of including an expander in the heat rejection system of an air-cooled power plant. The expander would be used during certain parts of the year to increase the total output of the power plant. Five different plant locations (Miami, San Francisco, Bakersfield, Chicago, Anchorage) were investigated to show the effect which climate has on the economic potential of this ammonia bottoming cycle. The study shows that the expected energy costs for the bottoming cycle only will be less than 50 mills/kWh for any of the five plant locations. This cost assumes that an ammonia phase-change heat rejection system is already a part of the existing plant. The colder climates of Chicago and Anchorage demonstrate an even smaller energy cost of less than 15 mills/kWh. Further investigation of the concept is merited to substantiate these costs and determine the needed technology.

Hauser, S.G.; Hane, G.J.; Johnson, B.M.

1982-07-01

378

High-power operation of 1cm laser diode bars on funryu heat sink cooled by fluorinated-refrigerant  

NASA Astrophysics Data System (ADS)

We investigated the properties of fluorinated refrigerants for high-power laser diode bars mounted on a funryu heat sink. The thermal conductivity of fluorinated refrigerants is about ten times lower than that of water, but they are less corrosive to funryu heat sinks. Using 3M's "Fluorinet" FC77 and "Novec" HFE-7300 and comparing them with water as refrigerants, we developed a new fluorinated refrigerant cooling device that is suitable for removing heat from highpower LDs and LD modules. This device achieved CW light-output power from a 1-cm LD bar equivalent to that for a cooling device using ion-exchange water. With HFE-7300 as the refrigerant, we achieved over 100 W of output power at a drive current of CW 120 A and over 1.5 kW for a stacked-LD module operated at a constant current of 55 A in continuous-wave (CW) mode. High-power LD bars subjected to lifetime testing under these conditions have been successfully running for over 15,000 consecutive hours.

Oishi, Satoru; Miyajima, Hirofumi; Suzuki, Noriyasu; Natsume, Tomoyuki; Fujita, Toru; Nishida, Koji; Kurino, Hironobu; Okamoto, Ryusuke; Kageyama, Nobuto; Suzuki, Nobutaka; Uchiyama, Takayuki; Kan, Hirofumi

2009-02-01

379

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

SciTech Connect

Potential applications of wind energy include not only large central turbines that can be utilized by utilities, but also dispersed systems for farms and other applications. The US Departments of Energy (DOE) and Agriculture (USDA) currently are establishing the feasibility of wind energy use in applications where the energy can be used as available, or stored in a simple form. These applications include production of hot water for rural sanitation, heating and cooling of rural structures and products, drying agricultural products, and irrigation. This study, funded by USDA, analyzed the economic feasibility of wind power in refrigeration cooling and water heating systems in food processing plants. Types of plants included were meat and poultry, dairy, fruit and vegetable, and aquaculture.

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

1980-03-01

380

A comparative study of rapid and slow furnace cooling effects on the superconducting properties of Pb-free and Pb-doped Bi2212 HTSC  

Microsoft Academic Search

A study of the Pb-doped Bi-2212 phase in comparison to that of the Pb-free Bi-2212 phase under two different conditions: (i) rapid cooling (RC) and furnace cooling (FC), and (ii) variation of sintering time from 12 to 144 h has been carried out. The Pb-doped samples showed a change, while the Pb-free samples did not show any change in the

G. K. Padam; S. N. Ekbote; D. K. Suri; Balvinder Gogia; K. B. Ravat; B. K. Das

1997-01-01

381

Sinusoidal Response of dc SQUIDs (Superconducting Quantum Interference Devices) for rf Power Measurements.  

National Technical Information Service (NTIS)

Current, power, and attenuation measurements with rf SQUIDs are based on the fact that the voltage from the microwave readout circuit can be made a nearly sinusoidal function of the magnetic flux threading the SQUID. The authors point out here that an asy...

R. L. Peterson

1987-01-01

382

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

SciTech Connect

This program was undertaken to build and operate the first Air2Air{trademark} Water Conservation Cooling Tower at a power plant, giving a validated basis and capability for water conservation by this method. Air2Air{trademark} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10%-25% annually, depending on the cooling tower location (climate).

Ken Mortensen

2009-06-30

383

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

Microsoft Academic Search

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

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

1998-01-01

384

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

E-print Network

if an electrically resistive structural material is used. An advanced blanket based on a self- cooled liquid breeder of this flux conservation, the energetic ions would never get to the wall. The magnetic energy wall and/or on the ion collector plates. Initial estimates indicate that about 70% of the ion energy

Raffray, A. René

385

REPRODUCTION AND DISTRIBUTION OF FISHES IN A COOLING LAKE: WISCONSIN POWER PLANT IMPACT STUDY  

EPA Science Inventory

Spatial and temporal patterns during reproduction and early life history of fishes were studied in a manmade cooling lake. Lake Columbia, impounded in 1974, near Portage, Wisconsin, has an area of 190 ha, a mean depth of 2.1 m, and a 15C temperature gradient derived from the ther...

386

Brookhaven program to develop a helium-cooled power transmission system  

Microsoft Academic Search

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

E. B. Forsyth

1975-01-01

387

Thermal and dynamic analysis of the RING (Radiatively-cooled, Inertially-driven Nuclear Generator) power system radiator  

SciTech Connect

The nuclear option for a space-based power system appears most suitable for missions that require long-term, sustained operation at power levels above 100 kWe. Systems currently available operate at relatively low thermal efficiencies (6--10%). Thus, a 100 kWe system must discharge nearly 2 MWth of waste heat through the comparatively inefficient process of radiative cooling. The impact of the resultant radiator assembly size on overall power system weight is significant, and has led to proposals for radiators with potentially higher efficiencies. Examples include the: liquid droplet radiator; fabric radiator; bubble membrane radiator; rotating film radiator; and dust radiator. 14 refs., 2 figs., 2 tabs.

Apley, W.J.; Babb, A.L.

1989-01-01

388

Investigation of Absorption Cooling Application Powered by Solar Energy in the South Coast Region of Turkey  

NASA Astrophysics Data System (ADS)

In this study, an absorption system using ammonia-water (NH3-H2O) solution has been theoretically examined in order to meet the cooling need of a detached building having 150 m2 floor area for Antalya, Mersin and Mugla provinces in Turkey. Hourly dynamic cooling load capacities of the building were determined by using Radiant Time Series (RTS) method in the chosen cities. For the analysis, hourly average meteorological data such as atmospheric air temperature and solar radiation belonging to the years 1998-2008 are used for performance prediction of the proposed system. Thermodynamic relations for each component of absorption cooling system is explained and coefficients of performance of the system are calculated. The maximum daily total radiation data were calculated as 7173 W/m2day on July 15, 7277 W/m2 day on July 19 and 7231 W/m2day on July 19 for Mersin, Antalya and Mugla, respectively on the 23° toward to south oriented panels from horizontal surface. The generator operating temperatures are considered between 90-130°C and the best result for 110°C is found the optimum degree for maximum coefficient of performance (COP) values at the highest solar radiation occurred time during the considered days for each province. The COP values varies between 0.521 and 0.530 for the provinces. In addition, absorber and condenser capacities and thermal efficiency for the absorption cooling system were calculated. The necessary evacuated tube collector area for the different provinces were found in the range of 45 m2 to 47 m2. It is shown that although the initial investment cost is higher for the proposed absorption cooling system, it is economically feasible because of its lower annual operation costs and can successfully be operated for the considered provinces.

Babayigit, O.; Aksoy, M. H.; Ozgoren, M.; Solmaz, O.

2013-04-01

389

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

SciTech Connect

The National Water, Energy and Carbon Sequestration simulation model (WECSsim) is being developed to address the question, 'Where in the current and future U.S. fossil fuel based electricity generation fleet are there opportunities to couple CO{sub 2} storage and extracted water use, and what are the economic and water demand-related impacts of these systems compared to traditional power systems?' The WECSsim collaborative team initially applied this framework to a test case region in the San Juan Basin, New Mexico. Recently, the model has been expanded to incorporate the lower 48 states of the U.S. Significant effort has been spent characterizing locations throughout the U.S. where CO{sub 2} might be stored in saline formations including substantial data collection and analysis efforts to supplement the incomplete brine data offered in the NatCarb database. WECSsim calculates costs associated with CO{sub 2} capture and storage (CCS) for the power plant to saline formation combinations including parasitic energy costs of CO{sub 2} capture, CO{sub 2} pipelines, water treatment options, and the net benefit of water treatment for power plant cooling. Currently, the model can identify the least-cost deep saline formation CO{sub 2} storage option for any current or proposed coal or natural gas-fired power plant in the lower 48 states. Initial results suggest that additional, cumulative water withdrawals resulting from national scale CCS may range from 676 million gallons per day (MGD) to 30,155 MGD depending on the makeup power and cooling technologies being utilized. These demands represent 0.20% to 8.7% of the U.S. total fresh water withdrawals in the year 2000, respectively. These regional and ultimately nation-wide, bottom-up scenarios coupling power plants and saline formations throughout the U.S. can be used to support state or national energy development plans and strategies.

Not Available

2011-04-01

390

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

NASA Technical Reports Server (NTRS)

We have demonstrated a high power intermodulation measurement set-up capable of delivering 30 W in each of two fundamental tones. For closely spaced frequencies (less than 35 MHz), the dynamic range of the measurement is limited by the nonlinear performance of the mixer in the front end of the HP71210C spectrum analyzer. A tunable TE(sub 011) mode copper cavity was fabricated in which one of the endwalls could be adjusted shifting its resonant frequency between 5.7 and 6.6 GHz. Since the Q-value of this cavity is high, greater than 10(exp 4), and its bandwidth is small, less than 1 MHz, it can be used to attenuate the two fundamental tones relative to one of the harmonic tones, which greatly enhances the dynamic range of the measurement. This set-up can be used to measure the two-tone intermodulation distortion of any passive microwave device, e.g. a HTS filter, a connector, a cable, etc., over a frequency range of 5.9 to 6.4 GHz and a power range of 0.1 to 30 W. The third order intercept (TOI) of a prototype HTS filter measured at powers up to 30 W was +81.3 dBm.

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

1999-01-01

391

Feasibility Study of Supercritical Light Water Cooled Reactors for Electrical Power Production, 5th Quarterly Report, October - December 2002  

SciTech Connect

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

Philip MacDonald; Jacopo Buongiorno; Cliff Davis; J. Stephen Herring; Kevan Weaver; Ron Latanision; Bryce Mitton; Gary Was; Luca Oriani; Mario Carelli; Dmitry Paramonov; Lawrence Conway

2003-01-01

392

An assessment of the use of direct contact condensers with wet cooling systems for utility steam power plants  

SciTech Connect

Potential use of a direct contact condenser for steam recovery at the turbine exhaust of a utility power plant using a wet cooling system is investigated. To maintain condensate separate from the cooling water, a bank of plate heat exchangers is used. In a case study for a nominal 130-MW steam power plant, two heat rejection systems, one using a conventional surface condenser and another using a direct contact condenser together with a set of plate heat exchangers are compared on the basis of their performance, operation and maintenance, and system economics. Despite a higher initial cost for the direct contact system, the advantages it offers suggests that this system is viable both technically and economically. Key to the improvements the direct contact system offers is a higher equivalent availability for the power system. Reduction of dissolved oxygen and other metallic ions in the condensate, reduced use of chemical scavengers and polishers, and potential elimination of a plant floor are also major benefits of this system. Drawbacks include added plant components and higher initial cost. The potential for long-term cost reduction for the direct contact system is also identified.

Bharathan, D.; Hoo, E. (National Renewable Energy Lab., Golden, CO (United States)); D'Errico, P. (Stone and Webster Engineering Corp., Boston, MA (United States))

1992-02-01

393

Power conversion system design for supercritical carbon dioxide cooled indirect cycle nuclear reactors  

E-print Network

The supercritical carbon dioxide (S-CO?) cycle is a promising advanced power conversion cycle which couples nicely to many Generation IV nuclear reactors. This work investigates the power conversion system design and ...

Gibbs, Jonathan Paul

2008-01-01

394

Modeling of the filling and cooling processes of hot fuel mains in Liquid Fuel Rocket Power Plant (LFRPP)  

NASA Astrophysics Data System (ADS)

A mathematical model of heat and mass exchange processes during filling and cooling of hot fuel mains of the Liquid Fuel Rocket Power Plant (LFRPP), which allows to define a mass consumption and distribution of two-phase flow parameters by the length of pipeline. Results of calculations are compared with experimental data, taken during filling of the main with a supply of liquid oxygen from the tank into the combustion chamber. Also, the results of modeling of hydrogen main dynamic characteristics of LFRPP in the same conditions are given.

Prisnyakov, V. F.; Pokrishkin, V. V.; Serebryansky, V. N.

395

Study on neutronic of very small Pb - Bi cooled no-onsite refueling nuclear power reactor (VSPINNOR)  

NASA Astrophysics Data System (ADS)

A conceptual design study on Very Small Pb-Bi No-Onsite Refueling Cooled Nuclear Reactor (VSPINNOR) with Uranium nitride fuel using MCNPX program has been performed. In this design the reactor core is divided into three regions with different enrichment. At the center of the core is laid fuel without enrichment (internal blanket). While for the outer region using fuel enrichment variations. VSPINNOR fast reactor was operated for 10 years without refueling. Neutronic analysis shows optimized result of VSPINNOR has a core of 50 cm radius and 100 cm height with 300 MWth thermal power output at 60% fuel fraction that can be operated 18 years without refueling or fuel shuffling.

Arianto, Fajar; Su'ud, Zaki; Zuhair

2014-09-01

396

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

Microsoft Academic Search

Thermal dissipation in power electronics systems is becoming an extremely important issue with the continuous growth of power density in their components. The primary cause of failure in this equipment is excessive temperatures in the critical components, such as semiconductors and transformers. This problem is particularly important in power electronic systems for space applications. These systems are usually housed in

Mariya Ivanova; Yvan Avenas; Christian Schaeffer; Jean-Bernard Dezord; Juergen Schulz-Harder

2006-01-01

397

Single-phase ac losses in prototype HTS conductors for superconducting power transmission lines  

SciTech Connect

The authors report single-phase ac loss measurements on 8, 4, and 3-layer, multi-strand, HTS prototype conductors for power transmission lines. They use both calorimetric and electrical techniques. The agreement between the two techniques suggests that the interlayer current distribution in one-meter long conductors are representative of those in long conductors. The losses for the 8 and 4-layer conductors are in rough agreement, with the 8-layer losses being somewhat lower. The 3-layer conductor losses are substantially higher--probably due to unbalanced azimuthal currents for this configuration.

Daney, D.E.; Maley, M.P.; Boenig, H.J.; Willis, J.O.; Coulter, J.Y. [Los Alamos National Lab., NM (United States); Gherardi, L.; Coletta, G. [Pirelli Cavi SpA (Italy)

1998-12-01

398

LATTICES FOR HIGH-POWER PROTON BEAM ACCELERATION AND SECONDARY BEAM COLLECTION AND COOLING.  

SciTech Connect

Rapid cycling synchrotrons are used to accelerate high-intensity proton beams to energies of tens of GeV for secondary beam production. After primary beam collision with a target, the secondary beam can be collected, cooled, accelerated or decelerated by ancillary synchrotrons for various applications. In this paper, we first present a lattice for the main synchrotron. This lattice has: (a) flexible momentum compaction to avoid transition and to facilitate RF gymnastics (b) long straight sections for low-loss injection, extraction, and high-efficiency collimation (c) dispersion-free straights to avoid longitudinal-transverse coupling, and (d) momentum cleaning at locations of large dispersion with missing dipoles. Then, we present a lattice for a cooler ring for the secondary beam. The momentum compaction across half of this ring is near zero, while for the other half it is normal. Thus, bad mixing is minimized while good mixing is maintained for stochastic beam cooling.

WANG, S.; WEI, J.; BROWN, K.; GARDNER, C.; LEE, Y.Y.; LOWENSTEIN, D.; PEGGS, S.; SIMOS, N.

2006-06-23

399

Test and simulation of a solar-powered absorption cooling machine  

Microsoft Academic Search

At the Institut fuer Thermodynamik und Waermetechnik (ITW) a solar cooling machine has been built for demonstration purposes. The main part of the device is an absorber\\/desorber unit which is mounted inside a concentrating solar collector. The working pair consists of NH3 used as the refrigerant and SrCl2 used as the absorbing medium. Performance of the solar refrigeration unit was

Alfred Erhard; Erich Hahne

1997-01-01

400

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

Microsoft Academic Search

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

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

2004-01-01

401

Presence of pathogenic microorganisms in power-plant cooling waters. Final report, October 1, 1981-June 30, 1983  

SciTech Connect

Air was sampled at the point of discharge and at short distances downwind and upwind from industrial and power-plant cooling towers. Both high-volume electrostatic and impinger type samplers were used. Concentrates of the air samples were analyzed for Legionnaires' Disease Bacteria (LDB). In some cases, the samples were also tested for the presence of free-living amoebae. The concentrations of LDB in the air samples were well below the minimal infectious dose for guinea pigs and precluded testing of the samples for infectious LDB. Results of LDB analysis were related to the meteorological conditions at the time of sampling. Generally, the concentrations of LDB in the air at the discharge of the cooling towers were 1 x 10/sup -6/ to 1 x 10/sup -7/ of that found in comparable volumes of tower basin water. During periods of high humidity and wind speed, LDB was detected in a few downwind samples and one upwind sample. One site with extensive construction and excavation activity had higher LDB concentrations in air samples relative to other sites. Nonpathogenic Naegleria were present in one of two air samples taken in the mist at the base of a natural-draft cooling tower.

Tyndall, R.L.

1983-07-01

402

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

Microsoft Academic Search

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

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

1987-01-01

403

Serial and parallel power equipment with high-temperature superconducting elements  

NASA Technical Reports Server (NTRS)

One of the prospective, practical applications of high-temperature superconductors is the fault-current limitation in electrical energy networks. The development and testing of experimental HTSC serial current limiters have been reported in the literature. A Hungarian electric power company has proposed the development of a parallel equipment for arc suppressing both in the industrial and customers' networks. On the basis of the company's proposal the authors have outlined the scheme of a compound circuit that can be applied both for current limitation and arc suppressing. In this paper the design principles and methods of the shunt equipment are presented. These principles involve the electrical, mechanical and cryogenic aspects with the special view on the electrical and mechanical connection between the HTSC material and the current lead. Preliminary experiments and tests have been carried out to demonstrate the validity of the design principles developed. The results of the experiments and of the technological investigations are presented.

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

1995-01-01

404

Cool Vest  

NASA Technical Reports Server (NTRS)

ILC, Dover Division's lightweight cooling garment, called Cool Vest was designed to eliminate the harmful effects of heat stress; increases tolerance time in hot environments by almost 300 percent. Made of urethane-coated nylon used in Apollo, it works to keep the body cool, circulating chilled water throughout the lining by means of a small battery-powered pump. A pocket houses the pump, battery and the coolant which can be ice or a frozen gel, a valve control allows temperature regulation. One version is self-contained and portable for unrestrained movement, another has an umbilical line attached to an external source of coolant, such as standard tap water, when extended mobility is not required. It is reported from customers that the Cool Vest pays for itself in increased productivity in very high temperatures.

1982-01-01

405

High-temperature superconducting quantum interference device with cooled LC resonant circuit for measuring alternating magnetic fields with improved signal-to-noise ratio  

SciTech Connect

Certain applications of superconducting quantum interference devices (SQUIDs) require a magnetic field measurement only in a very narrow frequency range. In order to selectively improve the alternating-current (ac) magnetic field sensitivity of a high-temperature superconductor SQUID for a distinct frequency, a single-coil LC resonant circuit has been used. Within the liquid nitrogen bath, the coil surrounds the SQUID and couples to it inductively. Copper coils with different numbers of windings were used to cover the frequency range from <1 to nearly 100 kHz. A superconducting coil made of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} tape conductor was also tested. With the LC circuit, the signal-to-noise ratio of measurements could be improved typically by one order of magnitude or more in a narrow frequency band around the resonance frequency exceeding a few kilohertz. The best attained equivalent magnetic field resolution was 2.5 fT/{radical}Hz at 88 kHz. The experimental findings are in good agreement with mathematical analysis of the circuit with copper coil.

Qiu Longqing; Zhang Yi; Krause, Hans-Joachim; Braginski, Alex I.; Usoskin, Alexander [Institute of Bio- and Nanosystem (IBN-2), Research Center Juelich, D-52425 Juelich (Germany) and Pohl Institute of Solid State Physics, Tongji University, Shanghai 200092 (China); Institute of Bio- and Nanosystem (IBN-2), Research Center Juelich, D-52425 Juelich (Germany); European High Temperature Superconductors GmbH and Co. KG, D-63450 Hanau (Germany)

2007-05-15

406

High-temperature superconducting quantum interference device with cooled LC resonant circuit for measuring alternating magnetic fields with improved signal-to-noise ratio.  

PubMed

Certain applications of superconducting quantum interference devices (SQUIDs) require a magnetic field measurement only in a very narrow frequency range. In order to selectively improve the alternating-current (ac) magnetic field sensitivity of a high-temperature superconductor SQUID for a distinct frequency, a single-coil LC resonant circuit has been used. Within the liquid nitrogen bath, the coil surrounds the SQUID and couples to it inductively. Copper coils with different numbers of windings were used to cover the frequency range from <1 to nearly 100 kHz. A superconducting coil made of YBa(2)Cu(3)O(7-delta) tape conductor was also tested. With the LC circuit, the signal-to-noise ratio of measurements could be improved typically by one order of magnitude or more in a narrow frequency band around the resonance frequency exceeding a few kilohertz. The best attained equivalent magnetic field resolution was 2.5 fT/radicalHz at 88 kHz. The experimental findings are in good agreement with mathematical analysis of the circuit with copper coil. PMID:17552846

Qiu, Longqing; Zhang, Yi; Krause, Hans-Joachim; Braginski, Alex I; Usoskin, Alexander

2007-05-01

407

Expansion-matched passively cooled heatsinks with low thermal resistance for high-power diode laser bars  

NASA Astrophysics Data System (ADS)

The lifetime of high-power diode lasers, which are cooled by standard copper heatsinks, is limited. The reasons are the aging of the indium solder normally employed as well as the mechanical stress caused by the mismatch between the copper heatsink (16 - 17ppm/K) and the GaAs diode laser bars (6 - 7.5 ppm/K). For micro - channel heatsinks corrosion and erosion of the micro channels limit the lifetime additionally. The different thermal behavior and the resulting stress cannot be compensated totally by the solder. Expansion matched heatsink materials like tungsten-copper or aluminum nitride reduce this stress. A further possible solution is a combination of copper and molybdenum layers, but all these materials have a high thermal resistance in common. For high-power electronic or low cost medical applications novel materials like copper/carbon compound, compound diamond or high-conductivity ceramics were developed during recent years. Based on these novel materials, passively cooled heatsinks are designed, and thermal and mechanical simulations are performed to check their properties. The expansion of the heatsink and the induced mechanical stress between laser bar and heatsink are the main tasks for the simulations. A comparison of the simulation with experimental results for different material combinations illustrates the advantages and disadvantages of the different approaches. Together with the boundary conditions the ideal applications for packaging with these materials are defined. The goal of the development of passively-cooled expansion-matched heatsinks has to be a long-term reliability of several 10.000h and a thermal resistance below 1 K/W.

Leers, Michael; Scholz, Christian; Boucke, Konstantin; Poprawe, Reinhart

2006-02-01

408

Current leads cooling for the series-connected hybrid magnets  

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

409

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

SciTech Connect

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, treatment requirements to use it at the plant, delivery and treatment economics, etc. SJGS, which is operated by Public Service of New Mexico (PNM) is located about 15 miles northwest of Farmington, New Mexico. It has four units with a total generating capacity of about 1,800 MW. The plant uses 22,400 acre-feet of water per year from the San Juan River with most of its demand resulting from cooling tower make-up. The plant is a zero liquid discharge facility and, as such, is well practiced in efficient water use and reuse. For the past few years, New Mexico has been suffering from a severe drought. Climate researchers are predicting the return of very dry weather over the next 30 to 40 years. Concern over the drought has spurred interest in evaluating the use of otherwise unusable saline waters. This deliverable describes possible test configurations for produced water demonstration projects at SJGS. The ability to host demonstration projects would enable the testing and advancement of promising produced water treatment technologies. Testing is described for two scenarios: Scenario 1--PNM builds a produced water treatment system at SJGS and incorporates planned and future demonstration projects into the design of the system. Scenario 2--PNM forestalls or decides not to install a produced water treatment system and would either conduct limited testing at SJGS (produced water would have to be delivered by tanker trucked) or at a salt water disposal facility (SWD). Each scenario would accommodate demonstration projects differently and these differences are discussed in this deliverable. PNM will host a demonstration test of water-conserving cooling technology--Wet Surface Air Cooling (WSAC) using cooling tower blowdown from the existing SJGS Unit 3 tower--during the summer months of 2005. If successful, there may be follow-on testing using produced water. WSAC is discussed in this deliverable. Recall that Deliverable 4, Emerging Technology Testing, describes the pilot testing conducted at a salt water disposal facility (SWD) by the CeraMem Corporation. This filtration technology could be a candidate for future demonstration testing and is also discussed in this deliverable.

Kent Zammit; Michael N. DiFilippo

2005-07-01

410

Superconducting cascade electron refrigerator  

NASA Astrophysics Data System (ADS)

The design and operation of an electronic cooler based on a combination of superconducting tunnel junctions is described. The cascade extraction of hot-quasiparticles, which stems from the energy gaps of two different superconductors, allows for a normal metal to be cooled down to about 100 mK starting from a bath temperature of 0.5 K. We discuss the practical implementation, potential performance, and limitations of such a device.

Camarasa-Gómez, M.; Di Marco, A.; Hekking, F. W. J.; Winkelmann, C. B.; Courtois, H.; Giazotto, F.

2014-05-01

411

Static forces in a superconducting magnet bearing  

SciTech Connect

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.

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

412

Superconductive wire  

SciTech Connect

This invention is comprised of a superconductive article including a first metallic tube having an interior surface and an exterior surface, said interior surface defining an interior hollow cavity, a layer of superconductive material surrounding said exterior surface of said first metallic tube, and, a second metallic tube having an interior surface and an exterior surface, said interior surface adjacent to said layer of superconductive material is provided together with processes of making such a superconductive article including, e.g., inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing and/or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for time sufficient for the superconductive material or superconductive precursor to exhibit superconductivity.

Korzekwa, D.A.; Bingert, J.F.; Peterson, D.E.; Sheinberg, H.

1992-12-31

413

Superconducting traveling wave accelerators  

NASA Astrophysics Data System (ADS)

The applicability of superconductivity to traveling wave accelerators is considered. Unlike CW operation of a superconducting standing wave or circulating wave accelerator section, which requires improvement factors (superconductor conductivity divided by copper conductivity) of about 10(6) in order to be of practical use, a Superconducting Traveling wave factors as low as about 10(3), which are attainable with niobium or lead at 4.2K, the temperature of liquid helium at atmospheric pressure. Changing from a copper traveling wave accelerator to SUTRA achieves the following: (1) for a given gradient SUTRA reduces the peak and average power requirements typically byu a factor of 2; (2) SUTRA reduces the peak power still further because it enables us to increase the filling time and thus trade pulse width for gradient; (3) SUTRA makes possible a reasonably long section at higher frequencies; and (4) SUTRA makes possible recirculation without additional RF average power.

Farkas, Z. D.

1984-11-01

414

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

SciTech Connect

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 the anode means for electrochemically reacting with oxygen in the pressurized air to produce electricity and water; first exhaust means for removing a mixture of oxygen-depleted air and product water from the cathode means; means for delivering a water fog stream to the anode means for mixture with the hydrogen rich fuel gas. The water fog stream being evaporated in the anode means to cool the stack; means for exhausting a mixture of hydrogen-depleted gas and water vapor from the anode means; reformer means for reforming a raw hydrocarbon fuel to the hydrogen rich fuel gas; and means for delivering the mixture of hydrogen-depleted exhaust gas and water vapor to the reformer means to provide water for the reforming reaction.

Levy, A.H.; Wertheim, R.J.

1989-09-12

415

Utilization of municipal wastewater for cooling in thermoelectric power plants: Evaluation of the combined cost of makeup water treatment and increased condenser fouling  

SciTech Connect

A methodology is presented to calculate the total combined cost (TCC) of water sourcing, water treatment and condenser fouling in the recirculating cooling systems of thermoelectric power plants. The methodology is employed to evaluate the economic viability of using treated municipal wastewater (MWW) to replace the use of freshwater as makeup water to power plant cooling systems. Cost analyses are presented for a reference power plant and five different tertiary treatment scenarios to reduce the scaling tendencies of MWW. Results indicate that a 550 MW sub-critical coal fired power plant with a makeup water requirement of 29.3 ML/day has a TCC of $3.0 - 3.2 million/yr associated with the use of treated MWW for cooling. (All costs USD 2009). This translates to a freshwater conservation cost of $0.29/kL, which is considerably lower than that of dry air cooling technology, $1.5/kL, as well as the 2020 conservation cost target set by the U.S. Department of Energy, $0.74/kL. Results also show that if the available price of freshwater exceeds that of secondarytreated MWW by more than $0.13-0.14/kL, it can be economically advantageous to purchase secondary MWW and treat it for utilization in the recirculating cooling system of a thermoelectric power plant.

Walker, Michael E.; Theregowda, Ranjani B.; Safari, Iman; Abbasian, Javad; Arastoopour, Hamid; Dzombak, David A.; Hsieh, Ming-Kai; Miller, David C.

2013-10-01

416

The distribution, abundance and life-histories of stoneflies (Plecoptera) and mayflies (Ephemeroptera) in a British River, warmed by cooling-water from a power station  

Microsoft Academic Search

1.The River Severn at Ironbridge is warmed by cooling-water from Ironbridge “A” power station. Water temperatures over the years 1965–1967 were raised by values ranging from 0.5 to 7.2°C above ambient.2.Collections of Plecoptera and Ephemeroptera were taken from three reaches in the vicinity of the cooling water discharge. “A” was situated 400 m upstream, “C” 800 m downstream and “E”,

T. E. Langford; Leatherhead Surrey

1971-01-01

417

Wet\\/dry cooling systems for fossil-fueled power plants: water conservation and plume abatement. Final report Jun 75Sep 77  

Microsoft Academic Search

Results of a study of technical and economic feasibilities of wet\\/dry cooling towers for water conservation and vapor plume abatement are given. Results of cost optimizations of wet\\/dry cooling for 1000-MWe fossil-fueled power plants are presented. Five sites in the western coal region and one in New York are evaluated for water conservation; four urban sites (Seattle, Cleveland, Newark, and

M. C. Hu; G. A. Englesson

1977-01-01

418

Novel Controls for Time-Dependent Economic Dispatch of Combined Cooling Heating and Power (CCHP)  

SciTech Connect

The research and development effort detailed in this report directly addresses the challenge of reducing U.S. industrial energy and carbon intensity by contributing to an increased understanding of potential CCHP technology, the CCHP market and the challenges of widespread adoption. This study developed a number of new tools, models, and approaches for the design, control, and optimal dispatch of various CCHP technologies. The UC Irvine campus served as a ‘living laboratory’ of new CCHP technologies and enabled the design and demonstration of several novel control methods. In particular, the integration of large scale thermal energy storage capable of shifting an entire day of cooling demand required a novel approach to the CCHP dispatch optimization. The thermal energy storage proved an economically viable resource which reduced both costs and emissions by enabling generators and chillers to operate under steady high efficiency conditions at all times of the day.

Samuelsen, Scott; Brouwer, Jack

2013-08-31

419

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

NASA Astrophysics Data System (ADS)

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%.

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

2014-07-01

420

Performance of the MFTF magnet cryogenic power leads  

SciTech Connect

The cryogenic power lead system for the MFTF superconducting magnets has been acceptance tested and operated with the magnets. This system, which includes 5-m-long superconducting buses, 1.5-m-long vapor-cooled transition leads, external warm buses, and a cryostack, can conduct up to 6000 A (dc) and operate adiabatically for long periods. We present both design details and performance data; our MFTF version is an example of a reliable lead system for large superconducting magnets contained in a much larger vacuum vessel.

VanSant, J.H.

1983-11-30

421

Muon acceleration in a superconducting proton Linac  

SciTech Connect

This note describes how a future Fermilab proton driver [1] based on TESLA superconducting linac modules can perform as both the source of protons to produce the muons and as the accelerator of the muons to be used for a neutrino factory or muon collider. Recent advances in muon cooling [2] have the promise of muon emittances that are compatible with the 1300 MHz accelerating structures that are the basis for the ILC design. In the design described here, H{sup -} ions are accelerated to 8 GeV in the superconducting Linac, then stripped, stored and bunched in a ring while the Linac cavities are rephased for muon acceleration. Then the protons are extracted from the ring to produce pions and muons which are cooled in a few hundred meters, accelerated to a few GeV and injected into the Linac at the {beta} = 1 point for acceleration to add 7 GeV. By recirculating the muons in the constant frequency section of such a proton driver Linac, even higher energies can be achieved quickly so that losses from muon decay are minimized. By adding additional refrigeration and RF power, the repetition rate of the Linac can be increased to make large increases in the average flux of a neutrino factory and the average luminosity of a muon collider. driver linac to be able to accelerate muons, including the costs to produce and cool the muons, will be considerably less than the costs estimated in previous neutrino factory design studies. We also believe that such an approach can produce a much higher neutrino flux and, because of the necessity for effective muon cooling, also be on the path to an energy frontier muon collider.

Popovic, Milorad; /Fermilab; Johnson, Rolland P.; /MUONS Inc., Batavia

2005-11-01

422

Reanalysis of the gas-cooled fast reactor experiments at the zero power facility proteus - Spectral indices  

SciTech Connect

The gas-cooled fast reactor (GCFR) concept was investigated experimentally in the PROTEUS zero power facility at the Paul Scherrer Inst. during the 1970's. The experimental program was aimed at neutronics studies specific to the GCFR and at the validation of nuclear data in fast spectra. A significant part of the program used thorium oxide and thorium metal fuel either distributed quasi-homogeneously in the reference PuO{sub 2}/UO{sub 2} lattice or introduced in the form of radial and axial blanket zones. Experimental results obtained at the time are still of high relevance in view of the current consideration of the Gas-cooled Fast Reactor (GFR) as a Generation-IV nuclear system, as also of the renewed interest in the thorium cycle. In this context, some of the experiments have been modeled with modern Monte Carlo codes to better account for the complex PROTEUS whole-reactor geometry and to allow validating recent continuous neutron cross-section libraries. As a first step, the MCNPX model was used to test the JEFF-3.1, JEFF-3.1.1, ENDF/B-VII.0 and JENDL-3.3 libraries against spectral indices, notably involving fission and capture of {sup 232}Th and {sup 237}Np, measured in GFR-like lattices. (authors)

Perret, G.; Pattupara, R. M. [Paul Scherrer Inst., 5232 Villigen (Switzerland); Girardin, G. [Ecole Polytechnique Federale de Lausanne, 1015 Lausanne (Switzerland); Chawla, R. [Paul Scherrer Inst., 5232 Villigen (Switzerland); Ecole Polytechnique Federale de Lausanne, 1015 Lausanne (Switzerland)

2012-07-01

423

The culture of estuarine fishes in net pens and cages in a power plant cooling system  

E-print Network

and Kelley (1970) cultured channel catfish commercially using the effluent from a Texas power plant. Rainbow trout, common carp (Cyprinus carpio), black drum (Pogonias cromis), red d (~d' * ll t (, t p d 11 t (M~d ~t lus) and Atlantic croaker ((((icro o... and Kelley (1970) cultured channel catfish commercially using the effluent from a Texas power plant. Rainbow trout, common carp (Cyprinus carpio), black drum (Pogonias cromis), red d (~d' * ll t (, t p d 11 t (M~d ~t lus) and Atlantic croaker ((((icro o...

Ojeda Gonzalez, Gabriel Mauricio

2012-06-07

424

Hybrid Evaporative - Condenser Cooling Tower  

Microsoft Academic Search

The need to save energy in power producing and power consuming systems and the fact that evaporative cooling is the most efficient method for heat rejection led to the design and testing of a model of a special cooling tower, fn this hybrid system an evaporative condenser is being built into the cooling tower and the advantages of evaporative cooling

Uriyel Fisher; Wolfgang Leidenfrost; Jiashang Li

1981-01-01

425

An air-cooled pulse tube cryocooler with 50 W cooling capacity at 77 K  

NASA Astrophysics Data System (ADS)

A pulse tube cryocooler with 50 W cooling capacity at 77 K is developed to cool superconducting devices mounted on automobiles. The envisioned cryocooler weight is less than 40 kg, and the input electric power is less than 1 kW. To achieve these requirements, the working frequency is increased to 75 Hz, and the dual-opposed pistons use gas bearings to reduce compressor weight and volume. The heat from the main heat exchanger is rejected by forced convective air instead of water. The compressor and the cold finger are carefully matched to improve the efficiency. The details of these will be presented in this paper. After some adjustment, a no load temperature for the pulse tube cryocooler of 40 K was achieved with 1 kW input electric power in surroundings at 298 K. At 77 K, the cooling capacity is 50 W. If the main heat exchanger is cooled by water at 293 K, the cooling capacity increases to 64 W, corresponding to a relative Carnot efficiency of 18%.

Hu, Jianying; Wang, Xiaotao; Zhu, Jian; Chen, Shuai; Luo, Ercang; Li, Haibin

2014-01-01

426

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

PubMed

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

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

2014-06-17

427

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

SciTech Connect

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.

Tyndall, R.L.

1982-10-01

428

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

SciTech Connect

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)

None

1980-01-01

429

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

Microsoft Academic Search

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,

Gunnar Olavi Tamm

2003-01-01

430

Kalkar nuclear power plant (SNR300) - A sodium-cooled fast breeder reactor prototype  

Microsoft Academic Search

The status of the Kalkar nuclear power plant in early summer 1986 is that, apart from later alterations to the workshop building, the assembly and non-nuclear commissioning work has practically been completed. From a technical point of view, nuclear commissioning of the plant can begin, but vital factors for this are the necessary nuclear licenses. The most important licensing prerequisites

Morgenstern

1987-01-01

431

Minimizing Data Center Cooling and Server Power Costs Ehsan Pakbaznia and Massoud Pedram  

E-print Network

that combine media and entertainment, financial/market information, and email/chat service). Data centers form in the energy consumption and power density of data centers. The electric bill of the data centers (including consumption, for a total electricity cost of about $4.5 billion [1]. This level of electricity consumption

Pedram, Massoud

432

Superconducting Levitation Styles for Superconducting Energy Storage Flywheel  

Microsoft Academic Search

The flywheel comprising of magnetic and superconducting bearings, which will provide a stable levitation of rotor, is fit for energy storage. According to the HTS cooling mode, there are ZFC bearings and FC bearings. ZFC bearings produce a large levitation force, but they ensure only one direction suspension. FC bearings produce less level of levitation force, but they provide passive

Jiqiang Tang; Yanshun Zhang; Jiancheng Fang

2007-01-01

433

Assessment of Thermal Control Technologies for Cooling Electric Vehicle Power Electronics  

Microsoft Academic Search

The U.S. Department of Energy (DOE) FreedomCAR Program's technical targets for the electric traction system (power electronics and electric machines) of advanced vehicles require significant reductions in volume, weight, and cost while also meeting performance and 15 year life requirements (1). The performance of the semiconductor switches and diodes, the ripple-current capability of the capacitors, and the life of the

Thomas Abraham; Kevin Bennion; Desikan Bharathan; Sreekant Narumanchi; Michael O'Keefe

434

Magnetic Levitators With Superconductive Components  

NASA Technical Reports Server (NTRS)

Magnetic noncontact levitators that include superconductive components provide vibration-damping suspension for cryogenic instruments, according to proposal. Because superconductive components attached to levitated cryogenic instruments, no additional coolant liquid or refrigeration power needed. Also because vibration-damping components of levitators located outside cold chambers, in ambient environment, not necessary to waste coolant liquid or refrigeration power on dissipation of vibrational energy. At least three levitating magnets and three superconductors necessary for stable levitation.

Dolgin, Benjamin P.

1995-01-01

435