National Library of Energy BETA

Sample records for magnetic refrigerant materials

  1. Magnetic refrigeration apparatus with belt of ferro or paramagnetic material

    DOE Patents [OSTI]

    Barclay, John A.; Stewart, Walter F.; Henke, Michael D.; Kalash, Kenneth E.

    1987-01-01

    A magnetic refrigerator operating in the 12 to 77K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

  2. Magnetic refrigeration apparatus with belt of ferro or paramagnetic material

    DOE Patents [OSTI]

    Barclay, J.A.; Stewart, W.F.; Henke, M.D.; Kalash, K.E.

    1986-04-03

    A magnetic refrigerator operating in the 12 to 77 K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

  3. Magnetic Refrigeration | GE Global Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Johnson, a materials scientist and project leader on GE's magnetic refrigeration project. ... materials would further improve the competitiveness of magnetic refrigeration technology. ...

  4. Ames Lab 101: Magnetic Refrigeration

    ScienceCinema (OSTI)

    Pecharsky, Vitalij

    2013-03-01

    Vitalij Pecharsky, distinguished professor of materials science and engineering, discusses his research in magnetic refrigeration at Ames Lab.

  5. Ames Lab 101: Magnetic Refrigeration

    SciTech Connect (OSTI)

    Pecharsky, Vitalij

    2011-01-01

    Vitalij Pecharsky, distinguished professor of materials science and engineering, discusses his research in magnetic refrigeration at Ames Lab.

  6. Active magnetic refrigerants based on Gd-Si-Ge material and refrigeration apparatus and process

    DOE Patents [OSTI]

    Gschneidner, Jr., Karl A.; Pecharsky, Vitalij K.

    1998-04-28

    Active magnetic regenerator and method using Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4, where x is equal to or less than 0.5, as a magnetic refrigerant that exhibits a reversible ferromagnetic/antiferromagnetic or ferromagnetic-II/ferromagnetic-I first order phase transition and extraordinary magneto-thermal properties, such as a giant magnetocaloric effect, that renders the refrigerant more efficient and useful than existing magnetic refrigerants for commercialization of magnetic regenerators. The reversible first order phase transition is tunable from approximately 30 K to approximately 290 K (near room temperature) and above by compositional adjustments. The active magnetic regenerator and method can function for refrigerating, air conditioning, and liquefying low temperature cryogens with significantly improved efficiency and operating temperature range from approximately 10 K to 300 K and above. Also an active magnetic regenerator and method using Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4, where x is equal to or greater than 0.5, as a magnetic heater/refrigerant that exhibits a reversible ferromagnetic/paramagnetic second order phase transition with large magneto-thermal properties, such as a large magnetocaloric effect that permits the commercialization of a magnetic heat pump and/or refrigerant. This second order phase transition is tunable from approximately 280 K (near room temperature) to approximately 350 K by composition adjustments. The active magnetic regenerator and method can function for low level heating for climate control for buildings, homes and automobile, and chemical processing.

  7. Active magnetic refrigerants based on Gd-Si-Ge material and refrigeration apparatus and process

    DOE Patents [OSTI]

    Gschneidner, K.A. Jr.; Pecharsky, V.K.

    1998-04-28

    Active magnetic regenerator and method using Gd{sub 5} (Si{sub x}Ge{sub 1{minus}x}){sub 4}, where x is equal to or less than 0.5, as a magnetic refrigerant that exhibits a reversible ferromagnetic/antiferromagnetic or ferromagnetic-II/ferromagnetic-I first order phase transition and extraordinary magneto-thermal properties, such as a giant magnetocaloric effect, that renders the refrigerant more efficient and useful than existing magnetic refrigerants for commercialization of magnetic regenerators. The reversible first order phase transition is tunable from approximately 30 K to approximately 290 K (near room temperature) and above by compositional adjustments. The active magnetic regenerator and method can function for refrigerating, air conditioning, and liquefying low temperature cryogens with significantly improved efficiency and operating temperature range from approximately 10 K to 300 K and above. Also an active magnetic regenerator and method using Gd{sub 5} (Si{sub x} Ge{sub 1{minus}x}){sub 4}, where x is equal to or greater than 0.5, as a magnetic heater/refrigerant that exhibits a reversible ferromagnetic/paramagnetic second order phase transition with large magneto-thermal properties, such as a large magnetocaloric effect that permits the commercialization of a magnetic heat pump and/or refrigerant. This second order phase transition is tunable from approximately 280 K (near room temperature) to approximately 350 K by composition adjustments. The active magnetic regenerator and method can function for low level heating for climate control for buildings, homes and automobile, and chemical processing. 27 figs.

  8. Low-temperature magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1983-05-26

    The invention relates to magnetic refrigeration and more particularly to low temperature refrigeration between about 4 and about 20 K, with an apparatus and method utilizing a belt of magnetic material passed in and out of a magnetic field with heat exchangers within and outside the field operably disposed to accomplish refrigeration.

  9. Final Scientific/Technical Report for DOE/EERE project Advanced Magnetic Refrigerant Materials

    SciTech Connect (OSTI)

    Johnson, Francis

    2014-06-30

    A team led by GE Global Research developed new magnetic refrigerant materials needed to enhance the commercialization potential of residential appliances such as refrigerators and air conditioners based on the magnetocaloric effect (a nonvapor compression cooling cycle). The new magnetic refrigerant materials have potentially better performance at lower cost than existing materials, increasing technology readiness level. The performance target of the new magnetocaloric material was to reduce the magnetic field needed to achieve 4 °C adiabatic temperature change from 1.5 Tesla to 0.75 Tesla. Such a reduction in field minimizes the cost of the magnet assembly needed for a magnetic refrigerator. Such a reduction in magnet assembly cost is crucial to achieving commercialization of magnetic refrigerator technology. This project was organized as an iterative alloy development effort with a parallel material modeling task being performed at George Washington University. Four families of novel magnetocaloric alloys were identified, screened, and assessed for their performance potential in a magnetic refrigeration cycle. Compositions from three of the alloy families were manufactured into regenerator components. At the beginning of the project a previously studied magnetocaloric alloy was selected for manufacturing into the first regenerator component. Each of the regenerators was tested in magnetic refrigerator prototypes at a subcontractor at at GE Appliances. The property targets for operating temperature range, operating temperature control, magnetic field sensitivity, and corrosion resistance were met. The targets for adiabatic temperature change and thermal hysteresis were not met. The high thermal hysteresis also prevented the regenerator components from displaying measurable cooling power when tested in prototype magnetic refrigerators. Magnetic refrigerant alloy compositions that were predicted to have low hysteresis were not attainable with conventional alloy processing methods. Preliminary experiments with rapid solidification methods showed a path towards attaining low hysteresis compositions should this alloy development effort be continued.

  10. Low-temperature magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, John A.

    1985-01-01

    The disclosure is directed to a low temperature 4 to 20 K. refrigeration apparatus and method utilizing a ring of magnetic material moving through a magnetic field. Heat exchange is accomplished in and out of the magnetic field to appropriately utilize the device to execute Carnot and Stirling cycles.

  11. Regenerator for Magnetic Refrigerants - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Industrial Technologies Industrial Technologies Building Energy Efficiency Building Energy Efficiency Advanced Materials Advanced Materials Find More Like This Return to Search Regenerator for Magnetic Refrigerants Ames Laboratory Contact AMES About This Technology Technology Marketing SummaryIowa State University and Ames Laboratory researchers have developed a new magnetic material that can be used at low temperatures (sub liquid hydrogen) for magnetic refrigerators. Magnetic refrigeration is

  12. Ternary Dy-Er-Al magnetic refrigerants

    DOE Patents [OSTI]

    Gschneidner, K.A. Jr.; Takeya, Hiroyuki

    1995-07-25

    A ternary magnetic refrigerant material comprising (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant. 29 figs.

  13. Ternary Dy-Er-Al magnetic refrigerants

    DOE Patents [OSTI]

    Gschneidner, Jr., Karl A.; Takeya, Hiroyuki

    1995-07-25

    A ternary magnetic refrigerant material comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant.

  14. Regenerator for Magnetic Refrigerants - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Regenerator for Magnetic Refrigerants Ames Laboratory Contact AMES About This Technology Technology Marketing Summary Ames Laboratory researchers have developed a new magnetic material that can be used at low temperatures (sub liquid hydrogen) for magnetic refrigerators. Description Magnetic refrigeration is being investigated as an alternative to conventional gas compressor technology for cooling and heating because of its potential to save energy and reduce operating costs. The potential

  15. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1983-10-11

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load. 7 figs.

  16. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, J.A.

    1982-01-20

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  17. Wheel-type magnetic refrigerator

    DOE Patents [OSTI]

    Barclay, John A.

    1983-01-01

    The disclosure is directed to a wheel-type magnetic refrigerator capable of cooling over a large temperature range. Ferromagnetic or paramagnetic porous materials are layered circumferentially according to their Curie temperature. The innermost layer has the lowest Curie temperature and the outermost layer has the highest Curie temperature. The wheel is rotated through a magnetic field perpendicular to the axis of the wheel and parallel to its direction of rotation. A fluid is pumped through portions of the layers using inner and outer manifolds to achieve refrigeration of a thermal load.

  18. Magnetic refrigeration apparatus and method

    DOE Patents [OSTI]

    Barclay, John A.; Overton, Jr., William C.; Stewart, Walter F.

    1984-01-01

    The disclosure relates to refrigeration through magnetizing and demagnitizing a body by rotating it within a magnetic field. Internal and external heat exchange fluids and in one embodiment, a regenerator, are used.

  19. Magnetic refrigeration apparatus and method

    DOE Patents [OSTI]

    Barclay, J.A.; Overton, W.C. Jr.; Stewart, W.F.

    The disclosure relates to refrigeration through magnetizing and demagnitizing a body by rotating it within a magnetic field. Internal and external heat exchange fluids and in one embodiment, a regenerator, are used.

  20. Magnetic refrigeration apparatus with heat pipes

    DOE Patents [OSTI]

    Barclay, J.A.; Prenger, F.C. Jr.

    1985-10-25

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe or pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  1. Magnetic refrigeration apparatus with heat pipes

    DOE Patents [OSTI]

    Barclay, John A.; Prenger, Jr., F. Coyne

    1987-01-01

    A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe of pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

  2. Magnetic Refrigeration | GE Global Research

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magnetocaloric Materials Chill Next-Generation Refrigerators Click to email this to a friend (Opens in new window) Share on Facebook (Opens in new window) Click to share (Opens in new window) Click to share on LinkedIn (Opens in new window) Click to share on Tumblr (Opens in new window) Magnetocaloric Materials Chill Next-Generation Refrigerators You've seen them. You may even decorate with them. The ubiquitous "sticker-uppers" that cover your refrigerator, helping to keep your

  3. Method of making active magnetic refrigerant, colossal magnetostriction and giant magnetoresistive materials based on Gd-Si-Ge alloys

    DOE Patents [OSTI]

    Gschneidner, Jr., Karl A.; Pecharsky, Alexandra O.; Pecharsky, Vitalij K.

    2003-07-08

    Method of making an active magnetic refrigerant represented by Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4 alloy for 0.ltoreq.x.ltoreq.1.0 comprising placing amounts of the commercially pure Gd, Si, and Ge charge components in a crucible, heating the charge contents under subambient pressure to a melting temperature of the alloy for a time sufficient to homogenize the alloy and oxidize carbon with oxygen present in the Gd charge component to reduce carbon, rapidly solidifying the alloy in the crucible, and heat treating the solidified alloy at a temperature below the melting temperature for a time effective to homogenize a microstructure of the solidified material, and then cooling sufficiently fast to prevent the eutectoid decomposition and improve magnetocaloric and/or the magnetostrictive and/or the magnetoresistive properties thereof.

  4. Bipolar pulse field for magnetic refrigeration

    DOE Patents [OSTI]

    Lubell, M.S.

    1994-10-25

    A magnetic refrigeration apparatus includes first and second steady state magnets, each having a field of substantially equal strength and opposite polarity, first and second bodies made of magnetocaloric material disposed respectively in the influence of the fields of the first and second steady state magnets, and a pulsed magnet, concentric with the first and second steady state magnets, and having a field which cycles between the fields of the first and second steady state magnets, thereby cyclically magnetizing and demagnetizing and thus heating and cooling the first and second bodies. Heat exchange apparatus of suitable design can be used to expose a working fluid to the first and second bodies of magnetocaloric material. A controller is provided to synchronize the flow of working fluid with the changing states of magnetization of the first and second bodies. 2 figs.

  5. Bipolar pulse field for magnetic refrigeration

    DOE Patents [OSTI]

    Lubell, Martin S.

    1994-01-01

    A magnetic refrigeration apparatus includes first and second steady state magnets, each having a field of substantially equal strength and opposite polarity, first and second bodies made of magnetocaloric material disposed respectively in the influence of the fields of the first and second steady state magnets, and a pulsed magnet, concentric with the first and second steady state magnets, and having a field which cycles between the fields of the first and second steady state magnets, thereby cyclically magnetizing and demagnetizing and thus heating and cooling the first and second bodies. Heat exchange apparatus of suitable design can be used to expose a working fluid to the first and second bodies of magnetocaloric material. A controller is provided to synchronize the flow of working fluid with the changing states of magnetization of the first and second bodies.

  6. Method of making active magnetic refrigerant materials based on Gd-Si-Ge alloys

    DOE Patents [OSTI]

    Pecharsky, Alexandra O.; Gschneidner, Jr., Karl A.; Pecharsky, Vitalij K.

    2006-10-03

    An alloy made of heat treated material represented by Gd.sub.5(Si.sub.xGe.sub.1-x).sub.4 where 0.47.ltoreq.x.ltoreq.0.56 that exhibits a magnetic entropy change (-.DELTA.S.sub.m) of at least 16 J/kg K, a magnetostriction of at least 2000 parts per million, and a magnetoresistance of at least 5 percent at a temperature of about 300K and below, and method of heat treating the material between 800 to 1600 degrees C. for a time to this end.

  7. Air Conditioning with Magnetic Refrigeration : An Efficient, Green Compact Cooling System Using Magnetic Refrigeration

    SciTech Connect (OSTI)

    2010-09-01

    BEETIT Project: Astronautics is developing an air conditioning system that relies on magnetic fields. Typical air conditioners use vapor compression to cool air. Vapor compression uses a liquid refrigerant to circulate within the air conditioner, absorb the heat, and pump the heat out into the external environment. Astronautics’ design uses a novel property of certain materials, called “magnetocaloric materials”, to achieve the same result as liquid refrigerants. These magnetocaloric materials essentially heat up when placed within a magnetic field and cool down when removed, effectively pumping heat out from a cooler to warmer environment. In addition, magnetic refrigeration uses no ozone-depleting gases and is safer to use than conventional air conditioners which are prone to leaks.

  8. The Nature of the Distinctive Microscopic Features in R5(SixGe1-x)4 Magnetic Refrigeration Materials

    SciTech Connect (OSTI)

    Ozan Ugurlu

    2006-05-01

    Magnetic refrigeration is a promising technology that offers a potential for high energy efficiency. The giant magnetocaloric effect of the R{sub 5}(Si{sub x}, Ge{sub 1-x}){sub 4} alloys (where R=rare-earth and O {le} x {le} 1), which was discovered in 1997, make them perfect candidates for magnetic refrigeration applications. In this study the microstructures of Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} alloys have been characterized using electron microscopy techniques, with the focus being on distinctive linear features first examined in 1999. These linear features have been observed in R{sub 5}(Si{sub x}, Ge{sub 1-x}){sub 4} alloys prepared from different rare-earths (Gd, Tb, Dy and Er) with different crystal structures (Gd{sub 5}Si{sub 4}-type orthorhombic, monoclinic and Gd{sub 5}Ge{sub 4}-type orthorhombic). Systematic scanning electron microscope studies revealed that these linear features are actually thin-plates, which grow along specific directions in the matrix material. The crystal structure of the thin-plates has been determined as hexagonal with lattice parameters a=b=8.53 {angstrom} and c=6.40 {angstrom} using selected area diffraction (SAD). Energy dispersive spectroscopy analysis, carried out in both scanning and transmission electron microscopes, showed that the features have a composition approximating to R{sub 5}(Si{sub x},Ge{sub 1-x}){sub 3}.phase. Orientation relationship between the matrix and the thin-plates has been calculated as [- 1010](1-211){sub p}//[010](10-2){sub m}. The growth direction of the thin plates are calculated as (22 0 19) and (-22 0 19) by applying the Ag approach of Zhang and Purdy to the SAD patterns of this system. High Resolution TEM images of the Gd{sub 5}Ge{sub 4} were used to study the crystallographic relationship. A terrace-ledge structure was observed at the interface and a 7{sup o} rotation of the reciprocal lattices with respect to each other, consistent with the determined orientation relationship, was noted. Both observations are consistent with the stated hypothesis that the growth direction of the thin-plates is parallel to an invariant line direction. Based on the terrace-ledge structure of the thin-plate interface a displacive-diffusional growth mechanism has been proposed to explain the rapid formation of the R{sub 5}(Si{sub x},Ge{sub 1-x}){sub 3} plates.

  9. Pecharsky talks magnetic refrigeration with Forbes | The Ames...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pecharsky talks magnetic refrigeration with Forbes In a May 6 article, Forbes contributor Hillary Brueck writes about the race to develop magnetic refrigeration and interviewed...

  10. Novel materials for laser refrigeration

    SciTech Connect (OSTI)

    Hehlen, Markus P

    2009-01-01

    The status of optical refrigeration of rare-earth-doped solids is reviewed, and the various factors that limit the performance of current laser-cooling materials are discussed. Efficient optical refrigeration is possible in materials for which {Dirac_h}{omega}{sub max} < E{sub p}/8, where {Dirac_h}{omega}{sub max} is the maximum phonon energy of the host material and E{sub p} is the pump energy of the rare-earth dopant. Transition-metal and OH{sup -}impurities at levels >100 ppb are believed to be the main factors for the limited laser-cooling performance in current materials. The many components of doped ZBLAN glass pose particular processing challenges. Binary fluoride glasses such as YF{sub 3}-LiF are considered as alternatives to ZBLAN. The crystalline system KPb{sub 2}CI{sub 5} :Dy{sup 3+} is identified as a prime candidate for high-efficiency laser cooling.

  11. Tunable Magnetic Regenerator/Refrigerant - Energy Innovation...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magnetic regenerators utilize the magnetocaloric effect--the ability of a magnetic field to reduce the magnetic part of a solid materials entropy, generating heat, and then ...

  12. Magnetic Refrigeration Technology for High Efficiency Air Conditioning

    SciTech Connect (OSTI)

    Boeder, A; Zimm, C

    2006-09-30

    Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate heat exchangers or oil distribution issues found in traditional vapor compression systems.

  13. Lanthanide Al-Ni base Ericsson cycle magnetic refrigerants

    DOE Patents [OSTI]

    Gschneidner, K.A. Jr.; Takeya, Hiroyuki

    1995-10-31

    A magnetic refrigerant for a magnetic refrigerator using the Ericsson thermodynamic cycle comprises DyAlNi and (Gd{sub 0.54}Er{sub 0.46})AlNi alloys having a relatively constant {Delta}Tmc over a wide temperature range. 16 figs.

  14. Lanthanide Al-Ni base Ericsson cycle magnetic refrigerants

    DOE Patents [OSTI]

    Gschneidner, Jr., Karl A.; Takeya, Hiroyuki

    1995-10-31

    A magnetic refrigerant for a magnetic refrigerator using the Ericsson thermodynamic cycle comprises DyAlNi and (Gd.sub.0.54 Er.sub.0.46)AlNi alloys having a relatively constant .DELTA.Tmc over a wide temperature range.

  15. Scaling and Optimization of Magnetic Refrigeration for Commercial Building HVAC Systems Greater than 175 kW in Capacity

    SciTech Connect (OSTI)

    Abdelaziz, Omar; West, David L; Mallow, Anne M

    2012-01-01

    Heating, ventilation, air-conditioning and refrigeration (HVACR) account for approximately one- third of building energy consumption. Magnetic refrigeration presents an opportunity for significant energy savings and emissions reduction for serving the building heating, cooling, and refrigeration loads. In this paper, we have examined the magnet and MCE material requirements for scaling magnetic refrigeration systems for commercial building cooling applications. Scaling relationships governing the resources required for magnetic refrigeration systems have been developed. As system refrigeration capacity increases, the use of superconducting magnet systems becomes more applicable, and a comparison is presented of system requirements for permanent and superconducting (SC) magnetization systems. Included in this analysis is an investigation of the ability of superconducting magnet based systems to overcome the parasitic power penalty of the cryocooler used to keep SC windings at cryogenic temperatures. Scaling relationships were used to develop the initial specification for a SC magnet-based active magnetic regeneration (AMR) system. An optimized superconducting magnet was designed to support this system. In this analysis, we show that the SC magnet system consisting of two 0.38 m3 regenerators is capable of producing 285 kW of cooling power with a T of 28 K. A system COP of 4.02 including cryocooler and fan losses which illustrates that an SC magnet-based system can operate with efficiency comparable to traditional systems and deliver large cooling powers of 285.4 kW (81.2 Tons).

  16. 4 K to 20 K rotational-cooling magnetic refrigerator capable of 1-mW to >1-W operation

    SciTech Connect (OSTI)

    Barclay, J.A.

    1980-02-01

    The low-temperature, magnetic entropy of certain single-crystal paramagnetic materials, such as DyPO/sub 4/, changes dramatically as the crystal rotates in a magnetic field. A new magnetic refrigerator design based on the anisotropic nature of such materials is presented. The key advantages of the rotational-cooling concept are (1) a single, rotary motion is required, (2) magnetic field shaping is not a problem because the entire working material is in a constant field, and (3) the refrigerator can be smaller than comparable magnetic refrigerators because the working material is entirely inside the magnet at all times. The main disadvantage of the rotational-cooling concept is that small-dimension single crystals are required.

  17. High temperature refrigerator

    DOE Patents [OSTI]

    Steyert, Jr., William A.

    1978-01-01

    A high temperature magnetic refrigerator which uses a Stirling-like cycle in which rotating magnetic working material is heated in zero field and adiabatically magnetized, cooled in high field, then adiabatically demagnetized. During this cycle said working material is in heat exchange with a pumped fluid which absorbs heat from a low temperature heat source and deposits heat in a high temperature reservoir. The magnetic refrigeration cycle operates at an efficiency 70% of Carnot.

  18. Refrigeration options for the Advanced Light Source Superbend Dipole Magnets

    SciTech Connect (OSTI)

    Green, M.A.; Hoyer, E.H.; Schlueter, R.D.; Taylor, C.E.; Zbasnik, J.; Wang, S.T.

    1999-07-09

    The 1.9 GeV Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL) produces photons with a critical energy of about 3.1 kev at each of its thirty-six 1.3 T gradient bending magnets. It is proposed that at three locations around the ring the conventional gradient bending magnets be replaced with superconducting bending magnets with a maximum field of 5.6 T. At the point where the photons are extracted, their critical energy will be about 12 keV. In the beam lines where the SuperBend superconducting magnets are installed, the X ray brightness at 20 keV will be increased over two orders of magnitude. This report describes three different refrigeration options for cooling the three SuperBend dipoles. The cooling options include: (1) liquid helium and liquid nitrogen cryogen cooling using stored liquids, (2) a central helium refrigerator (capacity 70 to 100 W) cooling all of the SuperBend magnets, (3) a Gifford McMahon (GM) cryocooler on each of the dipoles. This paper describes the technical and economic reasons for selecting a small GM cryocooler as the method for cooling the SuperBend dipoles on the LBNL Advanced Light Source.

  19. Corrosion of materials in absorption heating and refrigeration fluids

    SciTech Connect (OSTI)

    Griess, J.C.; DeVan, J.H.; Perez Blanco, H.

    1985-06-01

    The corrosion of metals and alloys in absorption refrigeration fluids has received little attention except for the behavior of steel and copper alloys in aqueous lithium bromide solutions. This report presents results of short-term corrosion tests on several materials in lithium bromide solutions as well as in other fluids of potential interest in advanced absorption machines. All materials tested had extremely high resistance to organic fluids, but in the aqueous systems some of the materials underwent localized attack. Type 304 stainless steel had acceptable corrosion resistance in most environments, but it underwent stress corrosion cracking in oxygen- or chromate-containing lithium bromide and even in the unstressed condition was subject to intergranular attack in hot concentrated caustic solutions. 10 refs., 2 figs., 4 tabs.

  20. Compatibility of refrigerants and lubricants with motor materials under retrofit conditions

    SciTech Connect (OSTI)

    Doerr, R.; Waite, T.

    1995-01-12

    Motor materials were exposed to original refrigerants R-11, R-12, R-22 and R-502 in the presence of mineral oil for 500 hours. These same materials were then exposed to alternative refrigerants R-123, R-134a, R-407C (R-32/R-125/R-134a) and R-404A (R-125/R-143a/R-134a), respectively, in the presence of the appropriate lubricant for 500 hours. As a control, some samples were exposed to the original refrigerant/mineral oil for a total of 1,000 hours. These tests were conducted to determine whether exposure to the original refrigerant/mineral oil would affect compatibility of the motor materials with the alternative refrigerant/lubricant after retrofit. Motor materials exposed to the alternative refrigerant and lubricant (after an initial exposure to the original refrigerant and mineral oil) appeared to be compatible with the alternative refrigerant and lubricant. The only concerns were embrittlement of the polyethylene terephthalate (PET) sheet and sleeving insulations, and delamination and blistering of the Nomex sheet insulation in the R-22, R-502, and R-12. Embrittlement of the PET materials was attributed to moisture present during the exposure. Separation of the 475 varnish from metal surfaces in the R-123 was also a concern. The sheet and sleeving insulations were affected by the original refrigerant/mineral oil to a greater extent than by the alternative refrigerant and lubricant.

  1. Investigation on the two-stage active magnetic regenerative refrigerator for liquefaction of hydrogen

    SciTech Connect (OSTI)

    Park, Inmyong; Park, Jiho; Jeong, Sangkwon; Kim, Youngkwon

    2014-01-29

    An active magnetic regenerative refrigerator (AMRR) is expected to be useful for hydrogen liquefaction due to its inherent high thermodynamic efficiency. Because the temperature of the cold end of the refrigerator has to be approximately liquid temperature, a large temperature span of the active magnetic regenerator (AMR) is indispensable when the heat sink temperature is liquid nitrogen temperature or higher. Since magnetic refrigerants are only effective in the vicinity of their own transition temperatures, which limit the temperature span of the AMR, an innovative structure is needed to increase the temperature span. The AMR must be a layered structure and the thermophysical matching of magnetic field and flow convection effects is very important. In order to design an AMR for liquefaction of hydrogen, the implementation of multi-layered AMR with different magnetic refrigerants is explored with multi-staging. In this paper, the performance of the multi-layered AMR using four rare-earth compounds (GdNi{sub 2}, Gd{sub 0.1}Dy{sub 0.9}Ni{sub 2}, Dy{sub 0.85}Er{sub 0.15}Al{sub 2}, Dy{sub 0.5}Er{sub 0.5}Al{sub 2}) is investigated. The experimental apparatus includes two-stage active magnetic regenerator containing two different magnetic refrigerants each. A liquid nitrogen reservoir connected to the warm end of the AMR maintains the temperature of the warm end around 77 K. High-pressure helium gas is employed as a heat transfer fluid in the AMR and the maximum magnetic field of 4 T is supplied by the low temperature superconducting (LTS) magnet. The temperature span with the variation of parameters such as phase difference between magnetic field and mass flow rate of magnetic refrigerants in AMR is investigated. The maximum temperature span in the experiment is recorded as 50 K and several performance issues have been discussed in this paper.

  2. Status of not-in-kind refrigeration technologies for household space conditioning, water heating and food refrigeration

    SciTech Connect (OSTI)

    Bansal, Pradeep; Vineyard, Edward Allan; Abdelaziz, Omar

    2012-01-01

    This paper presents a review of the next generation not-in-kind technologies to replace conventional vapor compression refrigeration technology for household applications. Such technologies are sought to provide energy savings or other environmental benefits for space conditioning, water heating and refrigeration for domestic use. These alternative technologies include: thermoacoustic refrigeration, thermoelectric refrigeration, thermotunneling, magnetic refrigeration, Stirling cycle refrigeration, pulse tube refrigeration, Malone cycle refrigeration, absorption refrigeration, adsorption refrigeration, and compressor driven metal hydride heat pumps. Furthermore, heat pump water heating and integrated heat pump systems are also discussed due to their significant energy saving potential for water heating and space conditioning in households. The paper provides a snapshot of the future R&D needs for each of the technologies along with the associated barriers. Both thermoelectric and magnetic technologies look relatively attractive due to recent developments in the materials and prototypes being manufactured.

  3. Magnetic Materials | Advanced Photon Source

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Internal Magnetic Materials The Magnetic Material Group (MMG) is part of the X-ray Science Division (XSD) at the Advanced Photon Source (APS). Our research focuses on the...

  4. Erbium-based magnetic refrigerant (regenerator) for passive cryocooler

    DOE Patents [OSTI]

    Gschneidner, K.A. Jr.; Pecharsky, V.K.

    1996-07-23

    A two stage Gifford-McMahon cryocooler is disclosed having a low temperature stage for reaching approximately 10K, wherein the low temperature stage includes a passive magnetic heat regenerator selected from the group consisting of Er{sub 6}Ni{sub 2}Sn, Er{sub 6}Ni{sub 2}Pb, Er{sub 6}Ni{sub 2}(Sn{sub 0.75}Ga{sub 0.25}), and Er{sub 9}Ni{sub 3}Sn comprising a mixture of Er{sub 3}Ni and Er{sub 6}Ni{sub 2}Sn in the microstructure. 14 figs.

  5. Erbium-based magnetic refrigerant (regenerator) for passive cryocooler

    DOE Patents [OSTI]

    Gschneidner, Jr., Karl A.; Pecharsky, Vitalij K.

    1996-07-23

    A two stage Gifford-McMahon cryocooler having a low temperature stage for reaching approximately 10K, wherein the low temperature stage includes a passive magnetic heat regenerator selected from the group consisting of Er.sub.6 Ni.sub.2 Sn, Er.sub.6 Ni.sub.2 Pb, Er.sub.6 Ni.sub.2 (Sn.sub.0.75 Ga.sub.0.25), and Er.sub.9 Ni.sub.3 Sn comprising a mixture of Er.sub.3 Ni and Er.sub.6 Ni.sub.2 Sn in the microstructure.

  6. Materials Compatibility and Lubricants Research on CFC-refrigerant substitutes. Quarterly MCLR Program technical progress report, July 1--September 30, 1995

    SciTech Connect (OSTI)

    Szymurski, S.R.; Hourahan, G.C.; Godwin, D.S.; Amrane, K.

    1995-10-01

    The Materials Compatibility and Lubricants Research (MCLR) program supports critical research to accelerate the introduction of CFC and HCFC refrigerant substitutes. The MCLR program addresses refrigerant and lubricant properties and materials compatibility. The primary elements of the work include data collection and dissemination, materials compatibility testing, and methods development. This report summarizes the research conducted during the third quarter of calendar year 1995 on the following projects: Thermophysical properties of HCFC alternatives; Compatibility of manufacturing process fluids with HFC refrigerants and ester lubricants; Compatibility of motor materials used in air-conditioning for retrofits with alternative refrigerants and lubricants; Compatibility of lubricant additives with HFC refrigerants and synthetic lubricants; Products of motor burnouts; Accelerated test methods for predicting the life of motor materials exposed to refrigerant-lubricant mixtures; Investigation of flushing and clean-out methods; Investigation into the fractionation of refrigerant blends; Lean flammability limits as a fundamental refrigerant property; Effect of selected contaminants in AC and R equipment; Study of foaming characteristics; Study of lubricant circulation in systems; Evaluation of HFC-245ca for commercial use in low pressure chillers; Infrared analysis of refrigerant mixtures; Refrigerant database; Refrigerant toxicity survey; Thermophysical properties of HFC-32, HFC-123, HCFC-124 and HFC-125; Thermophysical properties of HFC-143a and HFC-152a; Theoretical evaluations of R-22 alternative fluids; Chemical and thermal stability of refrigerant-lubricant mixtures with metals; Miscibility of lubricants with refrigerants; Viscosity, solubility and density measurements of refrigerant-lubricant mixtures; Electrohydrodynamic enhancement of pool and in-tube boiling of alternative refrigerants; Accelerated screening methods; and more.

  7. Magnetic Materials Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4-ID-C: Soft X-ray Magnetic Spectroscopy This beamline operates in the soft x-ray energy spectrum (500 - 2700 eV) using an electromagnetic helical undulator to provide circularly...

  8. Design Principles for Materials with Magnetic Functionality ...

    Office of Scientific and Technical Information (OSTI)

    Design Principles for Materials with Magnetic Functionality Citation Details In-Document Search Title: Design Principles for Materials with Magnetic Functionality This report ...

  9. Magnetic filtration process, magnetic filtering material, and...

    Office of Scientific and Technical Information (OSTI)

    The present invention provides magnetically responsive activated carbon, and a method of forming magnetically responsive activated carbon. The method of forming magnetically ...

  10. Fluorescent refrigeration

    DOE Patents [OSTI]

    Epstein, Richard I.; Edwards, Bradley C.; Buchwald, Melvin I.; Gosnell, Timothy R.

    1995-01-01

    Fluorescent refrigeration is based on selective radiative pumping, using substantially monochromatic radiation, of quantum excitations which are then endothermically redistributed to higher energies. Ultimately, the populated energy levels radiatively deexcite emitting, on the average, more radiant energy than was initially absorbed. The material utilized to accomplish the cooling must have dimensions such that the exciting radiation is strongly absorbed, but the fluorescence may exit the material through a significantly smaller optical pathlength. Optical fibers and mirrored glasses and crystals provide this requirement.

  11. Magnetic Filtration Process, Magnetic Filtering Material, and Method of

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Forming Magnetic Filtering Material - Energy Innovation Portal Industrial Technologies Industrial Technologies Find More Like This Return to Search Magnetic Filtration Process, Magnetic Filtering Material, and Method of Forming Magnetic Filtering Material Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryORNL researchers developed a new method for filtering materials and managing wastewater. This invention offers an integrated, intensified process

  12. Large entropy change accompanying two successive magnetic phase transitions in TbMn{sub 2}Si{sub 2} for magnetic refrigeration

    SciTech Connect (OSTI)

    Li, Guoxing; Cheng, Zhenxiang E-mail: cheng@uow.edu.au; Fang, Chunsheng; Dou, Shixue; Wang, Jianli E-mail: cheng@uow.edu.au; Ren, Qingyong

    2015-05-04

    Structural and magnetic properties in TbMn{sub 2}Si{sub 2} are studied by variable temperature X-ray diffraction, magnetization, electrical resistivity, and heat capacity measurements. TbMn{sub 2}Si{sub 2} undergoes two successive magnetic transitions at around T{sub c1} = 50 K and T{sub c2} = 64 K. T{sub c1} remains almost constant with increasing magnetic field, but T{sub c2} shifts significantly to higher temperature. Thus, there are two partially overlapping peaks in the temperature dependence of magnetic entropy change, i.e., −ΔS{sub M} (T). The different responses of T{sub c1} and T{sub c2} to external magnetic field, and the overlapping of −ΔS{sub M} (T) around T{sub c1} and T{sub c2} induce a large refrigerant capacity (RC) within a large temperature range. The large reversible magnetocaloric effect (−ΔS{sub M}{sup peak} ∼ 16 J/kg K for a field change of 0–5 T) and RC (=396 J/kg) indicate that TbMn{sub 2}Si{sub 2} could be a promising candidate for low temperature magnetic refrigeration.

  13. Fluorescent refrigeration

    DOE Patents [OSTI]

    Epstein, R.I.; Edwards, B.C.; Buchwald, M.I.; Gosnell, T.R.

    1995-09-05

    Fluorescent refrigeration is based on selective radiative pumping, using substantially monochromatic radiation, of quantum excitations which are then endothermically redistributed to higher energies. Ultimately, the populated energy levels radiatively deexcite emitting, on the average, more radiant energy than was initially absorbed. The material utilized to accomplish the cooling must have dimensions such that the exciting radiation is strongly absorbed, but the fluorescence may exit the material through a significantly smaller optical pathlength. Optical fibers and mirrored glasses and crystals provide this requirement. 6 figs.

  14. Refrigeration system

    SciTech Connect (OSTI)

    Pagani, R.F.; Clarke, K.J.; Avon, E.J.

    1986-11-11

    This patent describes a chamber including an expandable refrigerant system associated therewith. The system comprises reservoir containing an expandable refrigerant coolant and lead piping connecting the reservoir to conduits carrying the coolant therein. The chamber comprises top, bottom and side walls, accordingly defining an interior and an exterior to the chamber, one of the walls comprises a door affording access into the chamber, each of the walls being insulated with insulating material. At least one of the walls comprises a first layer of the insulating material extending thereover adjacent the exterior and a second layer of the insulating material extending thereover adjacent the interior. The reservoir, lead piping and conduits are disposed intermediate the first and second layers of insulating material thereby isolating them from both the interior and exterior. Heat transferring through the at least one wall is substantially absorbed by the coolant and the insulating material cooled by the coolant, before it is able to penetrate through the at least one wall, permitting a product placed in the chamber to effectively maintain or substantially maintain a selected even temperature.

  15. Electronic & Magnetic Materials & Devices Capabilities | Argonne...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Electronic & Magnetic Materials & Devices Capabilities Synthesis Colloidal chemistry and self-assembly techniques Complex oxide film synthesis via molecular beam epitaxy (DCA R450...

  16. ARTI refrigerant database

    SciTech Connect (OSTI)

    Calm, J.M.

    1998-08-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufactures and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on many refrigerants including propane, ammonia, water, carbon dioxide, propylene, ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyolester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates.

  17. ARTI refrigerant database

    SciTech Connect (OSTI)

    Calm, J.M.

    1997-02-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alterative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on various refrigerants. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyolester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates.

  18. Malone refrigeration

    SciTech Connect (OSTI)

    Swift, G.W.

    1993-01-01

    Malone refrigeration is the use of a liquid near its critical points without evaporations as working fluid in a regenerative or recuperative refrigeration cycle such as the Stirling and Brayton cycles. It's potential advantages include compactness, efficiency, an environmentally benign working fluid, and reasonable cost. One Malone refrigerator has been built and studied; two more are under construction. Malone refrigeration is such a new, relatively unexplored technology that the potential for inventions leading to improvements in efficiency and simplicity is very high.

  19. Semiconductor-based optical refrigerator

    DOE Patents [OSTI]

    Epstein, Richard I.; Edwards, Bradley C.; Sheik-Bahae, Mansoor

    2002-01-01

    Optical refrigerators using semiconductor material as a cooling medium, with layers of material in close proximity to the cooling medium that carries away heat from the cooling material and preventing radiation trapping. In addition to the use of semiconducting material, the invention can be used with ytterbium-doped glass optical refrigerators.

  20. ARTI Refrigerant Database

    SciTech Connect (OSTI)

    Calm, J.M.

    1992-04-30

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air- conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on R-32, R-123, R-124, R- 125, R-134a, R-141b, R142b, R-143a, R-152a, R-290 (propane), R-717 (ammonia), ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses polyalkylene glycol (PAG), ester, and other lubricants. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits.

  1. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    enhanced magnetic refrigeration at very low temperatures. Not Your Mother's Refrigerator Magnets Some day soon, magnets could do more than clutter up the front of your...

  2. Malone refrigeration

    SciTech Connect (OSTI)

    Swift, G W

    1992-01-01

    Malone refrigeration is the use of a liquid near its critical point, without evaporation, as working fluid in a refrigeration cycle such as the Stirling cycle. We discuss relevant properties of appropriate liquids, and describe two Malone refrigerators. The first completed several years ago, established the basic principles of use of liquids in such cycles. The second, now under construction, is a linear, free-piston machine.

  3. Malone refrigeration

    SciTech Connect (OSTI)

    Swift, G.W.

    1993-06-01

    Malone refrigeration is the use of a liquid near its critical points without evaporations as working fluid in a regenerative or recuperative refrigeration cycle such as the Stirling and Brayton cycles. It`s potential advantages include compactness, efficiency, an environmentally benign working fluid, and reasonable cost. One Malone refrigerator has been built and studied; two more are under construction. Malone refrigeration is such a new, relatively unexplored technology that the potential for inventions leading to improvements in efficiency and simplicity is very high.

  4. Near fifty percent sodium substituted lanthanum manganites—A potential magnetic refrigerant for room temperature applications

    SciTech Connect (OSTI)

    Sethulakshmi, N.; Anantharaman, M. R.; Al-Omari, I. A.; Suresh, K. G.

    2014-03-03

    Nearly half of lanthanum sites in lanthanum manganites were substituted with monovalent ion-sodium and the compound possessed distorted orthorhombic structure. Ferromagnetic ordering at 300 K and the magnetic isotherms at different temperature ranges were analyzed for estimating magnetic entropy variation. Magnetic entropy change of 1.5 J·kg{sup −1}·K{sup −1} was observed near 300 K. An appreciable magnetocaloric effect was also observed for a wide range of temperatures near 300 K for small magnetic field variation. Heat capacity was measured for temperatures lower than 300 K and the adiabatic temperature change increases with increase in temperature with a maximum of 0.62 K at 280 K.

  5. Magnetic spectroscopy and microscopy of functional materials

    SciTech Connect (OSTI)

    Jenkins, C.A.

    2011-01-28

    Heusler intermetallics Mn{sub 2}Y Ga and X{sub 2}MnGa (X; Y =Fe, Co, Ni) undergo tetragonal magnetostructural transitions that can result in half metallicity, magnetic shape memory, or the magnetocaloric effect. Understanding the magnetism and magnetic behavior in functional materials is often the most direct route to being able to optimize current materials for todays applications and to design novel ones for tomorrow. Synchrotron soft x-ray magnetic spectromicroscopy techniques are well suited to explore the the competing effects from the magnetization and the lattice parameters in these materials as they provide detailed element-, valence-, and site-specifc information on the coupling of crystallographic ordering and electronic structure as well as external parameters like temperature and pressure on the bonding and exchange. Fundamental work preparing the model systems of spintronic, multiferroic, and energy-related compositions is presented for context. The methodology of synchrotron spectroscopy is presented and applied to not only magnetic characterization but also of developing a systematic screening method for future examples of materials exhibiting any of the above effects. The chapter progression is as follows: an introduction to the concepts and materials under consideration (Chapter 1); an overview of sample preparation techniques and results, and the kinds of characterization methods employed (Chapter 2); spectro- and microscopic explorations of X{sub 2}MnGa/Ge (Chapter 3); spectroscopic investigations of the composition series Mn{sub 2}Y Ga to the logical Mn{sub 3}Ga endpoint (Chapter 4); and a summary and overview of upcoming work (Chapter 5). Appendices include the results of a Think Tank for the Graduate School of Excellence MAINZ (Appendix A) and details of an imaging project now in progress on magnetic reversal and domain wall observation in the classical Heusler material Co{sub 2}FeSi (Appendix B).

  6. Magnetic and Superconducting Materials at High Pressures

    SciTech Connect (OSTI)

    Struzhkin, Viktor V.

    2015-03-24

    The work concentrates on few important tasks in enabling techniques for search of superconducting compressed hydrogen compounds and pure hydrogen, investigation of mechanisms of high-Tc superconductivity, and exploring new superconducting materials. Along that route we performed several challenging tasks, including discovery of new forms of polyhydrides of alkali metal Na at very high pressures. These experiments help us to establish the experimental environment that will provide important information on the high-pressure properties of hydrogen-rich compounds. Our recent progress in RIXS measurements opens a whole field of strongly correlated 3d materials. We have developed a systematic approach to measure major electronic parameters, like Hubbard energy U, and charge transfer energy Δ, as function of pressure. This technique will enable also RIXS studies of magnetic excitations in iridates and other 5d materials at the L edge, which attract a lot of interest recently. We have developed new magnetic sensing technique based on optically detected magnetic resonance from NV centers in diamond. The technique can be applied to study superconductivity in high-TC materials, to search for magnetic transitions in strongly correlated and itinerant magnetic materials under pressure. Summary of Project Activities; development of high-pressure experimentation platform for exploration of new potential superconductors, metal polyhydrides (including newly discovered alkali metal polyhydrides), and already known superconductors at the limit of static high-pressure techniques; investigation of special classes of superconducting compounds (high-Tc superconductors, new superconducting materials), that may provide new fundamental knowledge and may prove important for application as high-temperature/high-critical parameter superconductors; investigation of the pressure dependence of superconductivity and magnetic/phase transformations in 3d transition metal compounds, including transitions from magnetic to nonmagnetic phases in a broad pressure-temperature range; using X-ray methods including the newly developed RIXS high-pressure technique to explore pressure-tuned electronic excitations in strongly correlated 3d-materials; and advancing transport and magnetic techniques for measurements on small samples at very high pressures in a wide temperature range, with the application of focused ion beam technology and photolithography tailored to the design of microcircuits down to a nanoscale size, thus expanding the horizon in the search for novel physical phenomena at ultrahigh pressures. Apply new optical magnetic sensing techniques with NV- centers in diamond to detect superconductivity and magnetic transitions with unprecedented spatial resolution.

  7. Final Technical Progress Report NANOSTRUCTURED MAGNETIC MATERIALS

    SciTech Connect (OSTI)

    Charles M. Falco

    2012-09-13

    This report describes progress made during the final phase of our DOE-funded program on Nanostructured Magnetic Materials. This period was quite productive, resulting in the submission of three papers and presentation of three talks at international conferences and three seminars at research institutions. Our DOE-funded research efforts were directed toward studies of magnetism at surfaces and interfaces in high-quality, well-characterized materials prepared by Molecular Beam Epitaxy (MBE) and sputtering. We have an exceptionally well-equipped laboratory for these studies, with: Thin film preparation equipment; Characterization equipment; Equipment to study magnetic properties of surfaces and ultra-thin magnetic films and interfaces in multi-layers and superlattices.

  8. Thermoacoustic refrigeration

    SciTech Connect (OSTI)

    Garrett, S.L.; Hofler, T.J. )

    1992-12-01

    Shortly after their introduction, chlorofluorocarbons (CFCs) used as working fluids in a vapor compression (Rankine) refrigeration cycle became dominant in almost all small and medium-scale food refrigerator/freezer and building/residential air-conditioning applications. That situation is about to change dramatically and, at this moment, unpredictably. Two recent events are responsible for the new era in refrigeration that will dawn before the beginning of the 21st Century. The most significant of these is the international ban on the production of CFCs which were found to be destroying the Earth's protective ozone layer. The second event was the discovery of high temperature superconductors and the development of high speed and high density electronic circuits that require active cooling. It is the purpose of this article to introduce an entirely new approach to refrigeration that was first discovered in the early 1980s. This new approach-thermoacoustic refrigeration-uses high intensity sound waves to pump heat, with inert gases as the working fluid.

  9. ARTI Refrigerant Database

    SciTech Connect (OSTI)

    Cain, J.M.

    1993-04-30

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R-134a, R-141b, R-142b, R-143a, R-152a, R-245ca, R-290 (propane), R-717 (ammonia), ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, ester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents to accelerate availability of the information and will be completed or replaced in future updates.

  10. ARTI Refrigerant Database

    SciTech Connect (OSTI)

    Calm, J.M.

    1992-11-09

    The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air- conditioning and refrigeration equipment. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R-134a, R-141b, R-142b, R-143a, R-152a, R-245ca, R-290 (propane), R- 717 (ammonia), ethers, and others as well as azeotropic and zeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, ester, and other synthetics as well as mineral oils. It also references documents on compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. A computerized version is available that includes retrieval software.

  11. Ames Laboratory scientists create cheaper magnetic material for...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory scientists create cheaper magnetic material for cars, wind turbines Contacts: For release: April 23, 2015 Karl A. Gschneidner, Division of Materials Sciences and...

  12. High-Efficiency, Cost-effective Thermoelectric Materials/Devices for Industrial Process Refrigeration and Waste Heat Recovery, STTR Phase II Final Report

    SciTech Connect (OSTI)

    Lin, Timothy

    2011-01-07

    This is the final report of DoE STTR Phase II project, “High-efficiency, Cost-effective Thermoelectric Materials/Devices for Industrial Process Refrigeration and Waste Heat Recovery”. The objective of this STTR project is to develop a cost-effective processing approach to produce bulk high-performance thermoelectric (TE) nanocomposites, which will enable the development of high-power, high-power-density TE modulus for waste heat recovery and industrial refrigeration. The use of this nanocomposite into TE modules are expected to bring about significant technical benefits in TE systems (e.g. enhanced energy efficiency, smaller sizes and light weight). The successful development and applications of such nanocomposite and the resultant TE modules can lead to reducing energy consumption and environmental impacts, and creating new economic development opportunities.

  13. Magnetism in Non-Traditional Materials

    SciTech Connect (OSTI)

    Menon, Madhu

    2013-09-17

    We performed a systematic microscopic investigation of two completely dissimilar materials (namely, ZnO and rhombohedral-C{sub 60} polymers) exhibiting ferromagnetism in the presence of defects, and showed that this new phenomena has a common origin and the mechanism responsible can be used as a powerful tool for inducing and tailoring magnetic features in systems which are not magnetic otherwise. Based on our findings we proposed a general recipe for developing ferromagnetism in new materials of great technological interest. Our results support the role of complimentary pairs of defects in inducing magnetism in otherwise non-magnetic materials belonging to two widely differing classes with no apparent correlation between them. In both classes, ferromagnetism is found to be enhanced when the two kinds of defects form structures (pathways) of alternating effective donor and acceptor crystal sites leading to the development of electron charge and spin density like waves. Using ab initio density functional theory calculations we predicted the existence of a new class of carbon cages formed via hybrid connection between planar graphene sheets and carbon nanotubes. The resulting novel structure has the appearance of ?nano-drum? and offers the exciting prospect of integrating useful device properties of both graphene as well as the nanotube into a single unit with tunable electronic properties. Creation of a hexagonal hole in the graphene portion of this structure results in significant magnetic moments for the edge atoms. The structure appears to be capable of sustaining ferrimagnetic state with the assistance of topological defects. The charge and spin distributions obtained in our calculations for the nano-drums are in striking contrast to those in planar graphene nanoribbons with a central hole. In this case, the central hole appears as the complimentary defect to those of the ribbon edges. Similar situation is found in case of the nano-drum in which the complimentary to the hole defects appear to be the pentagons along the curved surface of the drum. Charge oscillations found in the nano-drum are minimized in the nanoribbons. But more importantly, the hole edge atoms in the nano-drums retain significant magnetic moments; almost twice those of the corresponding ones in hydrogenated graphene nanoribbons (H-GNRs). These results suggest that the topological defects in the nano-drums may act like blocks to keep magnetic moments from ?leaking? out from the hole defects. This may have significant implications for the the use of nano-drums in magnetic storage technology where the ratio, magnetic-moment/weight, is of paramount importance in any futuristic device applications. One of the basic problems of the DFT/LSDA+U theory is the efficient evaluation of the U-term. With this in mind we proposed an alternative approach for its calculation which is based on the knowledge of the Hartree-Fock wave functions of the system under consideration. As a result, the proposed approach is closer to the basic definition of the DFT/LSDA+U scheme and its hybrid-DFT nature. According to our approach, the U value is obtained in a consistent and ab-initio way using the self-consistently calculated wave functions of the given system at the level of the HF approximation. Our method is applicable for systems which include more than one type of elements with localized d-orbitals. The method has been applied the case of the doped Zn(Co)O systems successfully. Currently, theories based on conventional superexchange or double-exchange interactions cannot explain long range magnetic order at concentrations below percolation threshold in dilute magnetic semiconductors. On the other hand, the codoping induced magnetism, which can justify magnetic interactions below percolation threshold, has eluded explanation. With this in mind, we proposed that defect-induced magnetism in codoped non-magnetic materials can be viewed within a molecular generalization of the atomic double-exchange and superexchange interactions applied to an arbitrary bipartite lattice host

  14. SYNTHESIS AND CHARACTERIZATION OF ADVANCED MAGNETIC MATERIALS

    SciTech Connect (OSTI)

    Monica Sorescu

    2004-09-22

    The work described in this grant report was focused mainly on the properties of novel magnetic intermetallics. In the first project, we synthesized several 2:17 intermetallic compounds, namely Nd{sub 2}Fe{sub 15}Si{sub 2}, Nd{sub 2}Fe{sub 15}Al{sub 2}, Nd{sub 2}Fe{sub 15}SiAl and Nd{sub 2}Fe{sub 15}SiMn, as well as several 1:12 intermetallic compounds, such as NdFe{sub 10}Si{sub 2}, NdFe{sub 10}Al{sub 2}, NdFe{sub 10}SiAl and NdFe{sub 10}MnAl. In the second project, seven compositions of Nd{sub x}Fe{sub 100-x-y}B{sub y} ribbons were prepared by a melt spinning method with Nd and B content increasing from 7.3 and 3.6 to 11 and 6, respectively. The alloys were annealed under optimized conditions to obtain a composite material consisting of the hard magnetic Nd{sub 2}Fe{sub 14}B and soft magnetic {alpha}-Fe phases, typical of a spring magnet structure. In the third project, intermetallic compounds of the type Zr{sub 1}Cr{sub 1}Fe{sub 1}T{sub 0.8} with T = Al, Co and Fe were subjected to hydrogenation. In the fourth project, we performed three crucial experiments. In the first experiment, we subjected a mixture of Fe{sub 3}O{sub 4} and Fe (80-20 wt %) to mechanochemical activation by high-energy ball milling, for time periods ranging from 0.5 to 14 hours. In the second experiment, we ball-milled Fe{sub 3}O{sub 4}:Co{sup 2+} (x = 0.1) for time intervals between 2.5 and 17.5 hours. Finally, we exposed a mixture of Fe{sub 3}O{sub 4} and Co (80-20 wt %) to mechanochemical activation for time periods ranging from 0.5 to 10 hours. In all cases, the structural and magnetic properties of the systems involved were elucidated by X-ray diffraction (XRD), Moessbauer spectroscopy and hysteresis loop measurements. The four projects resulted in four papers, which were published in Intermetallics, IEEE Transactions on Magnetics, Journal of Materials Science Letters and Materials Chemistry and Physics. The contributions reveal for the first time in literature the effect of substitutions on the hyperfine magnetic field of neodymium-based intermetallics, the correlation between structure and magnetic properties in spring magnets, the unique effects induced by hydrogenation on the hyperfine parameters of iron-rich intermetallics and the characteristics of the ball milling process in systems containing magnetite.

  15. REACT: Alternatives to Critical Materials in Magnets

    SciTech Connect (OSTI)

    2012-01-01

    REACT Project: The 14 projects that comprise ARPA-E’s REACT Project, short for “Rare Earth Alternatives in Critical Technologies”, are developing cost-effective alternatives to rare earths, the naturally occurring minerals with unique magnetic properties that are used in electric vehicle (EV) motors and wind generators. The REACT projects will identify low-cost and abundant replacement materials for rare earths while encouraging existing technologies to use them more efficiently. These alternatives would facilitate the widespread use of EVs and wind power, drastically reducing the amount of greenhouse gases released into the atmosphere.

  16. Magnetic filtration process, magnetic filtering material, and methods of forming magnetic filtering material

    DOE Patents [OSTI]

    Taboada-Serrano, Patricia; Tsouris, Constantino; Contescu, Cristian I; McFarlane, Joanna

    2013-10-08

    The present invention provides magnetically responsive activated carbon, and a method of forming magnetically responsive activated carbon. The method of forming magnetically responsive activated carbon typically includes providing activated carbon in a solution containing ions of ferrite forming elements, wherein at least one of the ferrite forming elements has an oxidation state of +3 and at least a second of the ferrite forming elements has an oxidation state of +2, and increasing pH of the solution to precipitate particles of ferrite that bond to the activated carbon, wherein the activated carbon having the ferrite particles bonded thereto have a positive magnetic susceptibility. The present invention also provides a method of filtering waste water using magnetic activated carbon.

  17. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for applications involving enhanced magnetic refrigeration at very low temperatures. ... In molecular form, "nanomagnets" might just be the key to refrigeration that uses less ...

  18. Refrigerant directly cooled capacitors

    DOE Patents [OSTI]

    Hsu, John S.; Seiber, Larry E.; Marlino, Laura D.; Ayers, Curtis W.

    2007-09-11

    The invention is a direct contact refrigerant cooling system using a refrigerant floating loop having a refrigerant and refrigeration devices. The cooling system has at least one hermetic container disposed in the refrigerant floating loop. The hermetic container has at least one electronic component selected from the group consisting of capacitors, power electronic switches and gating signal module. The refrigerant is in direct contact with the electronic component.

  19. Modeling Magnetism in Rare-Earth Intermetallic Materials | The Ames

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory Modeling Magnetism in Rare-Earth Intermetallic Materials Theoretical modeling has led to a key development in our understanding of the deeply complex magnetic properties in a series of rare-earth intermetallic materials. Rare-earth elements are unique in that their cores hold strongly localized electrons that underpin their novel magnetic properties. When combined with transition metals, rare earths become technologically-useful intermetallic materials. Here gadolinium-an element

  20. Final Report: Stability and Novel Properties of Magnetic Materials...

    Office of Scientific and Technical Information (OSTI)

    Final Report: Stability and Novel Properties of Magnetic Materials and Ferromagnet Insulator Interfaces Citation Details In-Document Search Title: Final Report: Stability and ...

  1. Extraordinary Responsive Rare Earth Magnetic Materials | The...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... magnetoresistance and magnetocaloric effect in Pr0.6Er0.4Al2. Journal of Alloys and ... A.G.; Vitalij K.P. Magnetic properties and magnetic entropy changes of MRE2Co7 compounds. ...

  2. Recent progress of magnetocaloric effect and magnetic refrigerant materials of Mn compounds (invited)

    SciTech Connect (OSTI)

    Wada, H. Takahara, T.; Katagiri, K.; Ohnishi, T.; Soejima, K.; Yamashita, K.

    2015-05-07

    Magnetocaloric and related properties of Ru and Ni substituted (MnFe){sub 2}(PSi) are presented. It is found that Ru and Ni are effective doping elements to reduce the thermal hysteresis of (MnFe){sub 2}(PSi). The origin of the thermal hysteresis is discussed on the basis of a thermodynamic model. It is shown that the elastic energy is responsible for the thermal hysteresis. We also show recent developments of the production process of Mn compounds in an industrial scale.

  3. ARTI refrigerant database

    SciTech Connect (OSTI)

    Calm, J.M.

    1999-01-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilities access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  4. ARTI refrigerant database

    SciTech Connect (OSTI)

    Calm, J.M.

    1996-11-15

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  5. ARTI refrigerant database

    SciTech Connect (OSTI)

    Calm, J.M.

    1996-07-01

    The Refrigerant Database is an information system on alternative refrigerants, associated lubricants, and their use in air conditioning and refrigeration. It consolidates and facilitates access to property, compatibility, environmental, safety, application and other information. It provides corresponding information on older refrigerants, to assist manufacturers and those using alternative refrigerants, to make comparisons and determine differences. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  6. Cryogenic Considerations for Superconducting Magnet Design for the Material Plasma Exposure eXperiment

    SciTech Connect (OSTI)

    Duckworth, Robert C; Demko, Dr. Jonathan A; Lumsdaine, Arnold; Caughman, John B; Goulding, Richard Howell; McGinnis, William Dean; Bjorholm, Thomas P; Rapp, Juergen

    2015-01-01

    In order to determine long term performance of plasma facing components such as diverters and first walls for fusion devices, next generation plasma generators are needed. A Material Plasma Exposure eXperiment (MPEX) has been proposed to address this need through the generation of plasmas in front of the target with electron temperatures of 1-15 eV and electron densities of 1020 to 1021 m-3. Heat fluxes on target diverters could reach 20 MW/m2. In order generate this plasma, a unique radio frequency helicon source and heating of electrons and ions through Electron Bernstein Wave (EBW) and Ion Cyclotron Resonance Heating (ICRH) has been proposed. MPEX requires a series of magnets with non-uniform central fields up to 2 T over a 5m length in the heating and transport region and 1 T uniform central field over a 1-m length on a diameter of 1.3 m. Given the field requirements, superconducting magnets are under consideration for MPEX. In order to determine the best construction method for the magnets, the cryogenic refrigeration has been analyzed with respect to cooldown and operational performance criteria for open-cycle and closed-cycle systems, capital and operating costs of these system, and maturity of supporting technology such as cryocoolers. These systems will be compared within the context of commercially available magnet constructions to determine the most economical method for MPEX operation. The current state of the MPEX magnet design including details on possible superconducting magnet configurations will be presented.

  7. Refrigerant recovery system

    SciTech Connect (OSTI)

    Abraham, A.W.

    1991-08-20

    This patent describes improvement in a refrigerant recovery apparatus of the type having inlet means for connecting to a refrigerant air system to withdraw refrigerant from the system, expansion means for converting refrigerant received from the system in liquid phase to a gaseous refrigerant, a compressor having a suction chamber with a suction inlet for receiving and pressurizing the gaseous refrigerant, the compressor having a housing containing oil for lubricating the compressor, a condenser for receiving the pressurized gaseous refrigerant and condensing it to liquid refrigerant, and a storage chamber for storing the liquid refrigerant. The improvement comprises in combination: oil separator means mounted exterior of the housing to one end of an inlet line, which has another end connected to the suction inlet of the compressor for receiving the flow of refrigerant from the refrigerated air system for separating out oil mixed with the refrigerant being received from the refrigerated air system prior to the refrigerant entering the suction inlet of the compressor; and the oil separator means being mounted at a lower elevation than the suction inlet of the compressor, the inlet line being unrestricted for allowing refrigerant flow to the compressor and oil from the compressor for draining oil in the housing of the compressor above the suction inlet back through the inlet line into the oil separator means when the compressor is not operating.

  8. Electronic & Magnetic Materials & Devices | Argonne National...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    laser spectroscopy, molecular beam epitaxy, and novel approaches for hybrid, organic and nanoparticle materials synthesis. Research activities include: Low-dimensional materials...

  9. Refrigerators and Refrigerator-Freezers (Appendix A1 after May...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Refrigerators and Refrigerator-Freezers (Appendix A1 after May 2, 2011) Refrigerators and Refrigerator-Freezers (Appendix A1 after May 2, 2011) The Department of Energy (DOE) ...

  10. Critical Magnetic Field Determination of Superconducting Materials

    SciTech Connect (OSTI)

    Canabal, A.; Tajima, T.; Dolgashev, V.A.; Tantawi, S.G.; Yamamoto, T.; /Tsukuba, Natl. Res. Lab. Metrol.

    2011-11-04

    Superconducting RF technology is becoming more and more important. With some recent cavity test results showing close to or even higher than the critical magnetic field of 170-180 mT that had been considered a limit, it is very important to develop a way to correctly measure the critical magnetic field (H{sup RF}{sub c}) of superconductors in the RF regime. Using a 11.4 GHz, 50-MW, <1 {mu}s, pulsed power source and a TE013-like mode copper cavity, we have been measuring critical magnetic fields of superconductors for accelerator cavity applications. This device can eliminate both thermal and field emission effects due to a short pulse and no electric field at the sample surface. A model of the system is presented in this paper along with a discussion of preliminary experimental data.

  11. ARTI Refrigerant Database

    SciTech Connect (OSTI)

    Calm, J.M.

    1994-05-27

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern.

  12. Digital lock-in detection of site-specific magnetism in magnetic materials

    DOE Patents [OSTI]

    Haskel, Daniel; Lang, Jonathan C.; Srajer, George

    2008-07-22

    The polarization and diffraction characteristics of x-rays incident upon a magnetic material are manipulated to provide a desired magnetic sensitivity in the material. The contrast in diffracted intensity of opposite helicities of circularly polarized x-rays is measured to permit separation of magnetic signals by element type and by atomic environment. This allows for the direct probing of magnetic signals from elements of the same species in nonequivalent atomic environments to better understand the behavior and characteristics of permanent magnetic materials. By using known crystallographic information together with manipulation of the polarization of x-rays having energies tuned near element-specific electronic excitations and by detecting and comparing the incident and diffracted photons at the same frequency, more accurate magnetic measurements can be made over shorter observation periods.

  13. Electromagnetic valve for controlling the flow of molten, magnetic material

    DOE Patents [OSTI]

    Richter, Tomas

    1998-01-01

    An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell.

  14. Electromagnetic valve for controlling the flow of molten, magnetic material

    DOE Patents [OSTI]

    Richter, T.

    1998-06-16

    An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell. 5 figs.

  15. Thermoacoustic refrigerator

    DOE Patents [OSTI]

    Moss, W.C.

    1997-10-07

    A thermoacoustic device is described having a thermal stack made from a piece of porous material which provides a desirable ratio of thermoacoustic area to viscous area, which has a low resistance to flow, which minimizes acoustic streaming and which has a high specific heat and low thermal conductivity. The thermal stack is easy and cheap to form and it can be formed in small sizes. Specifically, in one embodiment, a thermal stack which is formed by the natural structure of a porous material such as reticulated vitreous carbon is disclosed. The thermal stack is formed by machining a block of reticulated vitreous carbon into the required shape of the thermal stack. In a second embodiment, a micro-thermoacoustic device is disclosed which includes a thermal stack made of a piece of porous material such as reticulated vitreous carbon. In another embodiment, a heat exchanger is disclosed which is formed of a block of heat conductive open cell foam material. 13 figs.

  16. Thermoacoustic refrigerator

    DOE Patents [OSTI]

    Moss, William C. (San Mateo, CA)

    1997-01-01

    A thermoacoustic device having a thermal stack made from a piece of porous material which provides a desirable ratio of thermoacoustic area to viscous area, which has a low resistance to flow, which minimizes acoustic streaming and which has a high specific heat and low thermal conductivity is disclosed. The thermal stack is easy and cheap to form and it can be formed in small sizes. Specifically, in one embodiment, a thermal stack which is formed by the natural structure of a porous material such as reticulated vitreous carbon is disclosed. The thermal stack is formed by machining a block of reticulated vitreous carbon into the required shape of the thermal stack. In a second embodiment, a micro-thermoacoustic device is disclosed which includes a thermal stack made of a piece of porous material such as reticulated vitreous carbon. In another embodiment, a heat exchanger is disclosed which is formed of a block of heat conductive open cell foam material.

  17. Process Options for Nominal 2-K Helium Refrigeration System Designs

    SciTech Connect (OSTI)

    Peter Knudsen, Venkatarao Ganni

    2012-07-01

    Nominal 2-K helium refrigeration systems are frequently used for superconducting radio frequency and magnet string technologies used in accelerators. This paper examines the trade-offs and approximate performance of four basic types of processes used for the refrigeration of these technologies; direct vacuum pumping on a helium bath, direct vacuum pumping using full or partial refrigeration recovery, cold compression, and hybrid compression (i.e., a blend of cold and warm sub-atmospheric compression).

  18. Method of reducing chlorofluorocarbon refrigerant emissons to the atmosphere

    DOE Patents [OSTI]

    DeVault, Robert C.; Fairchild, Phillip D.; Biermann, Wendell J.

    1990-01-01

    A method is disclosed for reducing chloroflurocarbon (CFC) refrigerant emissions during removal or transfer or refrigerants from a vapor compression cooling system or heat pump which comprises contacting the refrigerant with a suitable sorbent material. The sorbent material allows for the storage and retention or the chlorofluorocarbon in non-gaseous form so that it does not tend to escape to the atmosphere where it would cause harm by contributing to ozone depletion. In other aspects of the invention, contacting of CFC refrigerants with sorbent material allows for purification and recycling of used refrigerant, and a device containing stored sorbent material can be employed in the detection of refrigerant leakage in a cooling system or heat pump.

  19. Young scientist discovers magnetic material unnecessary to create spin

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    current | Argonne National Laboratory Young scientist discovers magnetic material unnecessary to create spin current By Carla Reiter * July 23, 2015 Tweet EmailPrint It doesn't happen often that a young scientist makes a significant and unexpected discovery, but postdoctoral researcher Stephen Wu of the U.S. Department of Energy's Argonne National Laboratory just did exactly that. What he found-that you don't need a magnetic material to create spin current from insulators-has important

  20. Low-GWP Refrigerants for Refrigeration Systems | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low-GWP Refrigerants for Refrigeration Systems Low-GWP Refrigerants for Refrigeration Systems Brian Fricke conducts research in ORNL's Building Technologies Research & Integration Center. Brian Fricke conducts research in ORNL's Building Technologies Research & Integration Center. Life Cycle Climate Performance of supermarket refrigeration.<br /> Credit: Oak Ridge National Lab Life Cycle Climate Performance of supermarket refrigeration. Credit: Oak Ridge National Lab Brian Fricke

  1. Commercial Refrigeration Rebate Program

    Broader source: Energy.gov [DOE]

    Efficiency Vermont offers financial incentives to cover the incremental costs of energy efficient refrigeration for commercial, industrial, agricultural, and institutional buildings. 

  2. Chemically assisted mechanical refrigeration process

    DOE Patents [OSTI]

    Vobach, A.R.

    1987-06-23

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator. 5 figs.

  3. Chemically assisted mechanical refrigeration process

    DOE Patents [OSTI]

    Vobach, Arnold R.

    1987-01-01

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer (11) at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer (11) to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator (10) to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing he evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator.

  4. Chemically assisted mechanical refrigeration process

    DOE Patents [OSTI]

    Vobach, Arnold R.

    1987-01-01

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer (11) at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer (11) to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator (10) to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator.

  5. Chemically assisted mechanical refrigeration process

    DOE Patents [OSTI]

    Vobach, A.R.

    1987-11-24

    There is provided a chemically assisted mechanical refrigeration process including the steps of: mechanically compressing a refrigerant stream which includes vaporized refrigerant; contacting the refrigerant with a solvent in a mixer at a pressure sufficient to promote substantial dissolving of the refrigerant in the solvent in the mixer to form a refrigerant-solvent solution while concurrently placing the solution in heat exchange relation with a working medium to transfer energy to the working medium, said refrigerant-solvent solution exhibiting a negative deviation from Raoult's Law; reducing the pressure over the refrigerant-solvent solution in an evaporator to allow the refrigerant to vaporize and substantially separate from the solvent while concurrently placing the evolving refrigerant-solvent solution in heat exchange relation with a working medium to remove energy from the working medium to thereby form a refrigerant stream and a solvent stream; and passing the solvent and refrigerant stream from the evaporator. 5 figs.

  6. Suction muffler for refrigeration compressor

    DOE Patents [OSTI]

    Nelson, R.T.; Middleton, M.G.

    1983-01-25

    A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell. 5 figs.

  7. Suction muffler for refrigeration compressor

    DOE Patents [OSTI]

    Nelson, Richard T.; Middleton, Marc G.

    1983-01-01

    A hermetic refrigeration compressor includes a suction muffler formed from two pieces of plastic material mounted on the cylinder housing. One piece is cylindrical in shape with an end wall having an aperture for receiving a suction tube connected to the cylinder head. The other piece fits over and covers the other end of the cylindrical piece, and includes a flaring entrance horn which extends toward the return line on the sidewall of the compressor shell.

  8. Magnetocaloric Refrigeration | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    compression cycle and thus reduce greenhouse gas emissions by eliminating the use of high-global-warming-potential refrigerants. Refrigeration technologies based on MCE are...

  9. Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials

    DOE Patents [OSTI]

    Kraus, Robert H.; Matlashov, Andrei N.; Espy, Michelle A.; Volegov, Petr L.

    2010-03-30

    An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

  10. Refrigerated cryogenic envelope

    DOE Patents [OSTI]

    Loudon, John D.

    1976-11-16

    An elongated cryogenic envelope including an outer tube and an inner tube coaxially spaced within said inner tube so that the space therebetween forms a vacuum chamber for holding a vacuum. The inner and outer tubes are provided with means for expanding or contracting during thermal changes. A shield is located in the vacuum chamber intermediate the inner and outer tubes; and, a refrigeration tube for directing refrigeration to the shield is coiled about at least a portion of the inner tube within the vacuum chamber to permit the refrigeration tube to expand or contract along its length during thermal changes within said vacuum chamber.

  11. Dynamic high pressure process for fabricating superconducting and permanent magnetic materials

    DOE Patents [OSTI]

    Nellis, William J.; Geballe, Theodore H.; Maple, M. Brian

    1988-01-01

    Shock wave formation of thin layers of materials with improved superconducting and permanent magnetic properties and improved microstructures.

  12. Apparatus for magnetic separation of paramagnetic and diamagnetic material

    DOE Patents [OSTI]

    Doctor, R.D.

    1986-07-24

    The present invention relates to methods and apparatus for segregating paramagnetic from diamagnetic particles in particulate material and, in particular, to the open gradient magnetic separation of ash producing components and pyritic sulfur from coal. The apparatus includes a vertical cylinder and a rotatable vertical screw positioned within the cylinder, the screw having a helical blade angled downwardly and outwardly from the axis. Rotation of the vertical screw causes denser particles, which in the case of coal include pyritic sulfur and ash, which are paramagnetic, to migrate to the outside of the screw, and less dense particles, such as the low sulfur organic portion of the coal, which are diamagnetic, to migrate towards the center of the screw. A vibration mechanism attached to the screw causes the screw to vibrate during rotation, agitating and thereby accommodating further segregation of the particles. An open gradient magnetic field is applied circumferentially along the entire length of the screw by a superconducting quadrupole magnet. The open gradient magnetic field further segregates the paramagnetic-particles from the diamagnetic particles. The paramagnetic particles may then be directed from the cylinder into a first storage bin, and the diamagnetic particles, which are suitable for relatively clean combustion, may be directed into a second storage bin. 5 figs.

  13. Apparatus for magnetic separation of paramagnetic and diamagnetic material

    DOE Patents [OSTI]

    Doctor, R.D.

    1988-10-18

    The present invention relates to methods and apparatus for segregating paramagnetic from diamagnetic particles in particulate material and, in particular, to the open gradient magnetic separation of ash producing components and pyritic sulfur from coal. The apparatus includes a vertical cylinder and a rotatable vertical screw positioned within the cylinder, the screw having a helical blade angled downwardly and outwardly from the axis. Rotation of the vertical screw causes denser particles, which in the case of coal include pyritic sulfur and ash, which are paramagnetic, to migrate to the outside of the screw, and less dense particles, such as the low sulfur organic portion of the coal, which are diamagnetic, to migrate towards the center of the screw. A vibration mechanism attached to the screw causes the screw to vibrate during rotation, agitating and thereby accommodating further segregation of the particles. An open gradient magnetic field is applied circumferentially along the entire length of the screw by a superconducting quadrupole magnet. The open gradient magnetic field further segregates the paramagnetic particles from the diamagnetic particles. The paramagnetic particles may then be directed from the cylinder into a first storage bin, and the diamagnetic particles, which are suitable for relatively clean combustion, may be directed into a second storage bin. 5 figs.

  14. Apparatus for magnetic separation of paramagnetic and diamagnetic material

    DOE Patents [OSTI]

    Doctor, Richard D.

    1988-01-01

    The present invention relates to methods and apparatus for segregating paramagnetic from diamagnetic particles in particulate material and, in particular, to the open gradient magnetic separation of ash producing components and pyritic sulfur from coal. The apparatus includes a vertical cylinder and a rotatable vertical screw positioned within the cylinder, the screw having a helical blade angled downwardly and outwardly from the axis. Rotation of the vertical screw causes denser particles, which in the case of coal include pyritic sulfur and ash, which are paramagnetic, to migrate to the outside of the screw, and less dense particles, such as the low sulfur organic portion of the coal, which are diamagnetic, to migrate towards the center of the screw. A vibration mechanism attached to the screw causes the screw to vibrate during rotation, agitating and thereby accommodating further segregation of the particles. An open gradient magnetic field is applied circumferentially along the entire length of the screw by a superconducting quadropole magnet. The open gradient magnetic field further segregates the paramagnetic particles from the diamagnetic particles. The paramagnetic particles may then be directed from the cylinder into a first storage bin, and the diamagnetic particles, which are suitable for relatively clean combustion, may be directed into a second storage bin.

  15. Thermoacoustic engines and refrigerators

    SciTech Connect (OSTI)

    Swift, G.

    1996-12-31

    This report is a transcript of a practice lecture given in preparation for a review lecture on the operation of thermoacoustic engines and refrigerators. The author begins by a brief review of the thermodynamic principles underlying the operation of thermoacoustic engines and refrigerators. Remember from thermodynamics class that there are two kinds of heat engines, the heat engine or the prime mover which produces work from heat, and the refrigerator or heat pump that uses work to pump heat. The device operates between two thermal reservoirs at temperatures T{sub hot} and T{sub cold}. In the heat engine, heat flows into the device from the reservoir at T{sub hot}, produces work, and delivers waste heat into the reservoir at T{sub cold}. In the refrigerator, work flows into the device, lifting heat Q{sub cold} from reservoir at T{sub cold} and rejecting waste heat into the reservoir at T{sub hot}.

  16. International Refrigeration: Order (2012-CE-1510) | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    International Refrigeration: Order (2012-CE-1510) International Refrigeration: Order (2012-CE-1510) July 20, 2012 DOE ordered International Refrigeration Products to pay an 8,000 ...

  17. Compatibility of refrigerants and lubricants with electrical sheet insulation under retrofit conditions

    SciTech Connect (OSTI)

    Doerr, R.G.; Waite, T.D.

    1996-11-01

    To determine whether exposure to the original refrigerant/mineral oil would affect compatibility of sheet insulation with alternative refrigerant/lubricant after retrofit, sheet insulation was exposed at elevated temperature to the original refrigerant and mineral oil for 500 hours, followed by exposure to the alternative refrigerant and lubricant for 500 hours. Most of the sheet insulation materials exposed to the alternative refrigerant and lubricant (after an initial exposure to the original refrigerant and mineral oil) appeared to be compatible with the alternative refrigerant and lubricant. The only concern was delamination and blistering of the sheet insulation containing Nomex, especially after removal of absorbed refrigerant at high temperature. This was attributed to incompatibility of the adhesive and not to the Nomex itself. Embrittlement of the polyethylene terephthalate (PET) sheet was initially observed, but 2048 subsequent tests under extremely dry conditions showed that embrittlement of the PET materials was attributed to moisture present during the exposure.

  18. Magnetic preferential orientation of metal oxide superconducting materials

    DOE Patents [OSTI]

    Capone, D.W.; Dunlap, B.D.; Veal, B.W.

    1990-07-17

    A superconductor comprised of a polycrystalline metal oxide such as YBa[sub 2]Cu[sub 3]O[sub 7[minus]X] (where 0 < X < 0.5) exhibits superconducting properties and is capable of conducting very large current densities. By aligning the two-dimensional Cu-O layers which carry the current in the superconducting state in the a- and b-directions, i.e., within the basal plane, a high degree of crystalline axes alignment is provided between adjacent grains permitting the conduction of high current densities. The highly anisotropic diamagnetic susceptibility of the polycrystalline metal oxide material permits the use of an applied magnetic field to orient the individual crystals when in the superconducting state to substantially increase current transport between adjacent grains. In another embodiment, the anisotropic paramagnetic susceptibility of rare-earth ions substituted into the oxide material is made use of as an applied magnetic field orients the particles in a preferential direction. This latter operation can be performed with the material in the normal (non-superconducting) state. 4 figs.

  19. Magnetic preferential orientation of metal oxide superconducting materials

    DOE Patents [OSTI]

    Capone, Donald W.; Dunlap, Bobby D.; Veal, Boyd W.

    1990-01-01

    A superconductor comprised of a polycrystalline metal oxide such as YBa.sub.2 Cu.sub.3 O.sub.7-X (where 0material permits the use of an applied magnetic field to orient the individual crystals when in the superconducting state to substantially increase current transport between adjacent grains. In another embodiment, the anisotropic paramagnetic susceptibility of rare-earth ions substituted into the oxide material is made use of as an applied magnetic field orients the particles in a preferential direction. This latter operation can be performed with the material in the normal (non-superconducting) state.

  20. Experimental Investigation of Magnetic Superconducting, and other Phase Transitions in Novel f-Electron Materials at Ultra-high Pressures Using Designer Diamond Anvils

    SciTech Connect (OSTI)

    Maple, M. Brian

    2005-09-13

    Pressure is a powerful control parameter, owing to its ability to affect crystal and electronic structure without introducing defects, for the investigation of condensed matter systems. Some f-electron, heavy-fermion materials display interesting and novel behavior when exposed to pressures achievable with conventional experimental techniques; however, a growing number of condensed matter systems require extreme conditions such as ultrahigh pressures, high magnetic fields, and ultralow temperatures to sufficiently explore the important properties. To that end, we have been funded to develop an ultrahigh pressure facility at the University of California, San Diego (UCSD) in order to investigate superconductivity, magnetism, non-Fermi liquid behavior, and other phenomena under extreme conditions. Our goals for the second year of this grant were as follows: (a) perform electrical resistivity measurements on novel samples at a myriad of pressures using conventional piston-cylinder techniques, Bridgman anvil techniques, and diamond anvil cell technology; (b) install, commission, and operate an Oxford Kelvinox MX-100 dilution refrigerator for access to ultralow temperatures and high magnetic fields. (c) continue the development of diamond anvil cell (DAC) technology. During the past year, we have successfully installed the Oxford Kelvinox MX-100 dilution refrigerator and verified its operability down to 12 mK. We have begun an experimental program to systematically investigate the f-electron compound URu2Si2 under pressure and in the presence of magnetic fields. We have also continued our collaborative work with Sam Weir at Lawrence Livermore National Laboratory (LLNL) on Au4V and implemented a new corollary study on Au1-xVx using ultrahigh pressures. We have continued developing our DAC facility by designing and constructing an apparatus for in situ pressure measurement as well as designing high pressure cells. This report serves to highlight the progress we have made towards developing an ultrahigh pressure research facility at UCSD, the research performed in the past year, as well as future directions we plan to pursue.

  1. Downhole pulse tube refrigerators

    SciTech Connect (OSTI)

    Swift, G.; Gardner, D.

    1997-12-01

    This report summarizes a preliminary design study to explore the plausibility of using pulse tube refrigeration to cool instruments in a hot down-hole environment. The original motivation was to maintain Dave Reagor`s high-temperature superconducting electronics at 75 K, but the study has evolved to include three target design criteria: cooling at 30 C in a 300 C environment, cooling at 75 K in a 50 C environment, cooling at both 75 K and 30 C in a 250 C environment. These specific temperatures were chosen arbitrarily, as representative of what is possible. The primary goals are low cost, reliability, and small package diameter. Pulse-tube refrigeration is a rapidly growing sub-field of cryogenic refrigeration. The pulse tube refrigerator has recently become the simplest, cheapest, most rugged and reliable low-power cryocooler. The authors expect this technology will be applicable downhole because of the ratio of hot to cold temperatures (in absolute units, such as Kelvin) of interest in deep drilling is comparable to the ratios routinely achieved with cryogenic pulse-tube refrigerators.

  2. Materials, Strands, and Cables for Superconducting Accelerator Magnets. Final Report

    SciTech Connect (OSTI)

    Sumption, Mike D.; Collings, Edward W.

    2014-09-19

    This report focuses on Materials, Strands and Cables for High Energy Physics Particle accelerators. In the materials area, work has included studies of basic reactions, diffusion, transformations, and phase assemblage of Nb3Sn. These materials science aspects have been married to results, in the form of flux pinning, Bc2, Birr, and transport Jc, with an emphasis on obtaining the needed Jc for HEP needs. Attention has also been paid to the “intermediate-temperature superconductor”, magnesium diboride emphasis being placed on (i) irreversibility field enhancement, (ii) critical current density and flux pinning, and (iii) connectivity. We also report on studies of Bi-2212. The second area of the program has been in the area of “Strands” in which, aside from the materials aspect of the conductor, its physical properties and their influence on performance have been studied. Much of this work has been in the area of magnetization estimation and flux jump calculation and control. One of the areas of this work was strand instabilities in high-performance Nb3Sn conductors due to combined fields and currents. Additionally, we investigated quench and thermal propagation in YBCO coated conductors at low temperatures and high fields. The last section, “Cables”, focussed on interstrand contact resistance, ICR, it origins, control, and implications. Following on from earlier work in NbTi, the present work in Nb3Sn has aimed to make ICR intermediate between the two extremes of too little contact (no current sharing) and too much (large and unacceptable magnetization and associated beam de-focussing). Interstrand contact and current sharing measurements are being made on YBCO based Roebel cables using transport current methods. Finally, quench was investigated for YBCO cables and the magnets wound from them, presently with a focus on 50 T solenoids for muon collider applications.

  3. Thermoacoustic refrigerators and engines comprising cascading...

    Office of Scientific and Technical Information (OSTI)

    Thermoacoustic refrigerators and engines comprising cascading stirling thermodynamic units Title: Thermoacoustic refrigerators and engines comprising cascading stirling ...

  4. High Efficiency Low Emission Refrigeration System

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    * DOE reports, conference proceedings, journal articles, trade shows - Intermediate ... Refrigeration Systems," International Journal of Refrigeration (submitted). 14 Next ...

  5. Use of magnetic carbon composites from renewable resource materials for oil spill clean up and recovery

    DOE Patents [OSTI]

    Viswanathan, Tito

    2015-10-27

    A method of separating a liquid hydrocarbon material from a body of water, includes: (a) mixing magnetic carbon-metal nanocomposites with a liquid hydrocarbon material dispersed in a body of water to allow the magnetic carbon-metal nanocomposites each to be adhered by the liquid hydrocarbon material to form a mixture; (b) applying a magnetic force to the mixture to attract the magnetic carbon-metal nanocomposites each adhered by the liquid hydrocarbon material; and (c) removing the body of water from the magnetic carbon-metal nanocomposites each adhered by the liquid hydrocarbon material while maintaining the applied magnetic force. The magnetic carbon-metal nanocomposites is formed by subjecting one or more metal lignosulfonates or metal salts to microwave radiation, in presence of lignin/derivatives either in presence of alkali or a microwave absorbing material, for a period of time effective to allow the carbon-metal nanocomposites to be formed.

  6. Adsorption Refrigeration System

    SciTech Connect (OSTI)

    Wang, Kai; Vineyard, Edward Allan

    2011-01-01

    Adsorption refrigeration is an environmentally friendly cooling technology which could be driven by recovered waste heat or low-grade heat such as solar energy. In comparison with absorption system, an adsorption system has no problems such as corrosion at high temperature and salt crystallization. In comparison with vapor compression refrigeration system, it has the advantages of simple control, no moving parts and less noise. This paper introduces the basic theory of adsorption cycle as well as the advanced adsorption cycles such as heat and mass recovery cycle, thermal wave cycle and convection thermal wave cycle. The types, characteristics, advantages and drawbacks of different adsorbents used in adsorption refrigeration systems are also summarized. This article will increase the awareness of this emerging cooling technology among the HVAC engineers and help them select appropriate adsorption systems in energy-efficient building design.

  7. Refrigeration Playbook: Natural Refrigerants; Selecting and Designing Energy-Efficient Commercial Refrigeration Systems That Use Low Global Warming Potential Refrigerants

    SciTech Connect (OSTI)

    Nelson, Caleb; Reis, Chuck; Nelson, Eric; Armer, James; Arthur, Rob; Heath, Richard; Rono, James; Hirsch, Adam; Doebber, Ian

    2015-03-01

    This report provides guidance for selecting and designing energy efficient commercial refrigeration systems using low global warming potential refrigerants. Refrigeration systems are generally the largest energy end use in a supermarket type building, often accounting for more than half of a building's energy consumption.

  8. Method and apparatus for separating materials magnetically. [Patent application; iron pyrite from coal

    DOE Patents [OSTI]

    Hise, E.C. Jr.; Holman, A.S.; Friedlaender, F.J.

    1980-11-06

    Magnetic and nonmagnetic materials are separated by passing stream thereof past coaxial current-carrying coils which produce a magnetic field wherein intensity varies sharply with distance radially of the axis of the coils.

  9. Thermoacoustic engines and refrigerators

    SciTech Connect (OSTI)

    Swift, G.W.

    1995-07-01

    We ordinarily think of a sound wave in a gas as consisting of coupled pressure and displacement oscillations. However, temperature oscillations always accompany the pressure changes. The combination of all these oscillations, and their interaction with solid boundaries, produces a rich variety of `thermoacoustic` effects. Although these effects as they occur in every-day life are too small to be noticed, one can harness extremely loud sound waves in acoustically sealed chambers to produce powerful heat engines, heat pumps and refrigerators. Whereas typical engines and refrigerators have crankshaft-coupled pistons or rotating turbines, thermoacoustic engines and refrigerators have at most a single flexing moving part (as in a loudspeaker) with no sliding seals. Thermoacoustic devices may be of practical use where simplicity, reliability or low cost is more important than the highest efficiency (although one cannot say much more about their cost-competitiveness at this early stage). This paper discusses the fundamentals of thermoacoustic engines and refrigerators, research in this field, and their commercial development. 16 refs., 5 figs.

  10. Extreme solid state refrigeration using nanostructured Bi-Te alloys.

    SciTech Connect (OSTI)

    Lima Sharma, Ana L.; Spataru, Dan Catalin; Medlin, Douglas L.; Sharma, Peter Anand; Morales, Alfredo Martin

    2009-09-01

    Materials are desperately needed for cryogenic solid state refrigeration. We have investigated nanostructured Bi-Te alloys for their potential use in Ettingshausen refrigeration to liquid nitrogen temperatures. These alloys form alternating layers of Bi{sub 2} and Bi{sub 2}Te{sub 3} blocks in equilibrium. The composition Bi{sub 4}Te{sub 3} was identified as having the greatest potential for having a high Ettingshausen figure of merit. Both single crystal and polycrystalline forms of this material were synthesized. After evaluating the Ettingshausen figure of merit for a large, high quality polycrystal, we simulated the limits of practical refrigeration in this material from 200 to 77 K using a simple device model. The band structure was also computed and compared to experiments. We discuss the crystal growth, transport physics, and practical refrigeration potential of Bi-Te alloys.

  11. Magnetic mesoporous material for the sequestration of algae

    DOE Patents [OSTI]

    Trewyn, Brian G.; Kandel, Kapil; Slowing, Igor Ivan; Lee, Show-Ling

    2014-09-09

    The present invention provides a magnetic mesoporous nanoparticle that includes a mesoporous silicate nanoparticle and iron oxide. The present invention also provides a method of using magnetic mesoporous nanoparticles to sequester microorganisms from a media.

  12. The Hall D solenoid helium refrigeration system at JLab

    SciTech Connect (OSTI)

    Laverdure, Nathaniel A.; Creel, Jonathan D.; Dixon, Kelly d.; Ganni, Venkatarao; Martin, Floyd D.; Norton, Robert O.; Radovic, Sasa

    2014-01-01

    Hall D, the new Jefferson Lab experimental facility built for the 12GeV upgrade, features a LASS 1.85 m bore solenoid magnet supported by a 4.5 K helium refrigerator system. This system consists of a CTI 2800 4.5 K refrigerator cold box, three 150 hp screw compressors, helium gas management and storage, and liquid helium and nitrogen storage for stand-alone operation. The magnet interfaces with the cryo refrigeration system through an LN2-shielded distribution box and transfer line system, both designed and fabricated by JLab. The distribution box uses a thermo siphon design to respectively cool four magnet coils and shields with liquid helium and nitrogen. We describe the salient design features of the cryo system and discuss our recent commissioning experience.

  13. Compact acoustic refrigerator

    DOE Patents [OSTI]

    Bennett, Gloria A.

    1992-01-01

    A compact acoustic refrigeration system actively cools components, e.g., electrical circuits (22), in a borehole environment. An acoustic engine (12, 14) includes first thermodynamic elements (12) for generating a standing acoustic wave in a selected medium. An acoustic refrigerator (16, 26, 28) includes second thermodynamic elements (16) located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements (16) and a relatively hot temperature at a second end of the second thermodynamic elements (16). A resonator volume (18) cooperates with the first and second thermodynamic elements (12, 16) to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements (12, 16), first heat pipes (24, 26) transfer heat from the heat load (22) to the second thermodynamic elements (16) and second heat pipes (28, 32) transfer heat from first and second thermodynamic elements (12, 16) to the borehole environment.

  14. Compact acoustic refrigerator

    DOE Patents [OSTI]

    Bennett, G.A.

    1992-11-24

    A compact acoustic refrigeration system actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature at a second end of the second thermodynamic elements. A resonator volume cooperates with the first and second thermodynamic elements to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements, first heat pipes transfer heat from the heat load to the second thermodynamic elements and second heat pipes transfer heat from first and second thermodynamic elements to the borehole environment. 18 figs.

  15. Superfluid thermodynamic cycle refrigerator

    DOE Patents [OSTI]

    Swift, Gregory W.; Kotsubo, Vincent Y.

    1992-01-01

    A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of .sup.3 He in a single phase .sup.3 He-.sup.4 He solution. The .sup.3 He in superfluid .sup.4 He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid .sup.3 He at an initial concentration in superfluid .sup.4 He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of .sup.4 He while restricting passage of .sup.3 He. The .sup.3 He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

  16. Superfluid thermodynamic cycle refrigerator

    DOE Patents [OSTI]

    Swift, G.W.; Kotsubo, V.Y.

    1992-12-22

    A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of [sup 3]He in a single phase [sup 3]He-[sup 4]He solution. The [sup 3]He in superfluid [sup 4]He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid [sup 3]He at an initial concentration in superfluid [sup 4]He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of [sup 4]He while restricting passage of [sup 3]He. The [sup 3]He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K. 12 figs.

  17. Compact acoustic refrigerator

    SciTech Connect (OSTI)

    Bennett, G.A.

    1991-12-31

    This invention is comprised of a compact acoustic refrigeration system that actively cools components, e.g., electrical circuits, in a borehole environment. An acoustic engine includes first thermodynamic elements for generating a standing acoustic wave in a selected medium. An acoustic refrigerator includes second thermodynamic elements located in the standing wave for generating a relatively cold temperature at a first end of the second thermodynamic elements and a relatively hot temperature at a second end of the second thermodynamic elements. A resonator volume cooperates with the first and second thermodynamic elements to support the standing wave. To accommodate the high heat fluxes required for heat transfer to/from the first and second thermodynamic elements, first heat pipes transfer heat from the heat load to the second thermodynamic elements and second heat pipes transfer heat from first and second thermodynamic elements to the borehole environment.

  18. Novel Magnetic States in the Heavy-Fermion Quantum-Critical Material

    Office of Scientific and Technical Information (OSTI)

    CeRhIn5 at High Magnetic Fields Studied by NMR (Technical Report) | SciTech Connect Novel Magnetic States in the Heavy-Fermion Quantum-Critical Material CeRhIn5 at High Magnetic Fields Studied by NMR Citation Details In-Document Search Title: Novel Magnetic States in the Heavy-Fermion Quantum-Critical Material CeRhIn5 at High Magnetic Fields Studied by NMR Authors: Mounce, Andrew M. [1] ; Thompson, Joe David [1] ; Bauer, Eric Dietzgen [1] ; Reyes, A. P. [2] ; Kuhns, P. L. [2] + Show Author

  19. Novel Magnetic States in the Heavy-Fermion Quantum-Critical Material

    Office of Scientific and Technical Information (OSTI)

    CeRhIn5 at High Magnetic Fields Studied by NMR (Technical Report) | SciTech Connect Novel Magnetic States in the Heavy-Fermion Quantum-Critical Material CeRhIn5 at High Magnetic Fields Studied by NMR Citation Details In-Document Search Title: Novel Magnetic States in the Heavy-Fermion Quantum-Critical Material CeRhIn5 at High Magnetic Fields Studied by NMR × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of

  20. Exploring nanoscale magnetism in advanced materials with polarized X-rays

    Office of Scientific and Technical Information (OSTI)

    Exploring nanoscale magnetism in advanced materials with polarized X-rays Peter Fischer Center for X-ray Optics Lawrence Berkeley National Laboratory 1 Cyclotron Rd Berkeley, CA 94270 U.S.A e-mail address: PJFischer@lbl.gov ABSTRACT Nanoscale magnetism is of paramount scientific interest and high technological relevance. To control magnetization on a nanoscale, both external magnetic fields and spin polarized currents, which generate a spin torque onto the local spin configuration, are being

  1. High frequency transformers and high Q factor inductors formed using epoxy-based magnetic polymer materials

    DOE Patents [OSTI]

    Sanchez, Robert O.; Gunewardena, Shelton; Masi, James V.

    2007-11-27

    An electrical component in the form of an inductor or transformer is disclosed which includes one or more coils and a magnetic polymer material located near the coils or supporting the coils to provide an electromagnetic interaction therewith. The magnetic polymer material is preferably a cured magnetic epoxy which includes a mercaptan derivative having a ferromagnetic atom chemically bonded therein. The ferromagnetic atom can be either a transition metal or rare-earth atom.

  2. High frequency transformers and high Q factor inductors formed using epoxy-based magnetic polymer materials

    DOE Patents [OSTI]

    Sanchez, Robert O.; Gunewardena, Shelton; Masi, James V.

    2005-03-29

    An electrical component in the form of an inductor or transformer is disclosed which includes one or more coils and a magnetic polymer material located near the coils or supporting the coils to provide an electromagnetic interaction therewith. The magnetic polymer material is preferably a cured magnetic epoxy which includes a mercaptan derivative having a ferromagnetic atom chemically bonded therein. The ferromagnetic atom can be either a transition metal or rare-earth atom.

  3. New Advanced Refrigeration Technology Provides Clean Energy,...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... ORNL and Hillphoenix, found solutions to both challenges-the refrigerant leakage and high-global warming potential refrigerants-by using CO2 as the refrigerant and confining it to ...

  4. Refrigerator-freezer energy testing with alternative refrigerants

    SciTech Connect (OSTI)

    Vineyard, E.A.; Sand, J.R.; Miller, W.A.

    1989-01-01

    As a result of the Montreal Protocol that limits the production of ozone-depleting refrigerants, manufacturers are searching for alternatives to replace the R12 that is presently used in residential refrigerator-freezers. Before an alternative can be selected, several issues must be resolved. Among these are energy impacts, system compatibility, cost, and availability. In an effort to determine the energy impacts of some of the alternatives, energy consumption tests were performed in accordance with section 8 of the Association of Home Appliance Manufacturers (AHAM) standard for household refrigerators and household freezers. The results are presented for an 18 cubic foot (0.51 cubic meter), top-mount refrigerator-freezer with a static condenser using the following refrigerants: R12, R500, R12/Dimethyl-ether (DME), R22/R142b, and R134a. Conclusions from the AHAM test are that R500 and R12 /DME have a reduced energy consumption relative to R12 when replaced in the test unit with no modifications to the refrigeration system. Run times were slightly lower than R12 for both refrigerants indicating a higher capacity. While the R134a and R22/R142b results were less promising refrigeration system, such as a different capillary tube or compressor, may improve their performance. 12 refs., 2 figs., 3 tabs.

  5. Measurements with reticulated vitreous carbon stacks in thermoacoustic prime movers and refrigerators

    SciTech Connect (OSTI)

    Adeff, J.A.; Hofler, T.J.; Atchley, A.A.; Moss, W.C.

    1998-07-01

    Reticulated vitreous carbon has been successfully used as a stack material in thermoacoustic prime movers and refrigerators. It is a rigid glassy carbon material, with a porous spongelike structure. Test results indicate peak pressure amplitudes of up to 32{percent} in a prime mover, and refrigeration performance comparable to that of a traditional plastic roll stack. {copyright} {ital 1998 Acoustical Society of America.}

  6. Case Study: Transcritical Carbon Dioxide Supermarket Refrigeration...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    We compare refrigeration system performance to that for a supermarket having nearly identical layout and refrigeration loads, in a similar climate and of similar vintage, that uses ...

  7. Next Generation Household Refrigerator | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Next Generation Household Refrigerator Next Generation Household Refrigerator Embraco's high efficiency, oil-free linear compressor.
    Credit: Whirlpool Embraco's high ...

  8. New Energy Efficiency Standards for Commercial Refrigeration...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    for Commercial Refrigeration Equipment to Cut Businesses' Energy Bills and Carbon Pollution New Energy Efficiency Standards for Commercial Refrigeration Equipment to Cut...

  9. Multi-stage Cascaded Stirling Refrigerator

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Multi-stage Cascaded Stirling Refrigerator Multi-stage Cascaded Stirling Refrigerator Los Alamos National Laboratory (LANL) researchers have developed a multi-stage...

  10. Commercial Refrigeration Equipment | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    standards. File Commercial Refrigeration Equipment -- v2.0 More Documents & Publications Beverage Vending Machines Commercial Refrigeration Equipment Fluorescent Lamp Ballasts

  11. Kazuhiro Hono, Magnetic Materials Center Managing Director, NIMS...

    Broader source: Energy.gov (indexed) [DOE]

    PDF icon SessionA7HonoNIMS.pdf More Documents & Publications Spomenka Kobe, Jozef Stefan Institut, Rare Earth Magnets in Europe Tom Lograsso, Ames Laboratory (Iowa State ...

  12. Helium dilution refrigeration system

    DOE Patents [OSTI]

    Roach, Patrick R.; Gray, Kenneth E.

    1988-01-01

    A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains .sup.3 He and .sup.4 He liquids which are precooled by a coupled container containing .sup.3 He liquid, enabling the phase separation of a .sup.3 He rich liquid phase from a dilute .sup.3 He-.sup.4 He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the .sup.3 He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute .sup.3 He-.sup.4 He liquid phase.

  13. Helium dilution refrigeration system

    DOE Patents [OSTI]

    Roach, P.R.; Gray, K.E.

    1988-09-13

    A helium dilution refrigeration system operable over a limited time period, and recyclable for a next period of operation is disclosed. The refrigeration system is compact with a self-contained pumping system and heaters for operation of the system. A mixing chamber contains [sup 3]He and [sup 4]He liquids which are precooled by a coupled container containing [sup 3]He liquid, enabling the phase separation of a [sup 3]He rich liquid phase from a dilute [sup 3]He-[sup 4]He liquid phase which leads to the final stage of a dilution cooling process for obtaining low temperatures. The mixing chamber and a still are coupled by a fluid line and are maintained at substantially the same level with the still cross sectional area being smaller than that of the mixing chamber. This configuration provides maximum cooling power and efficiency by the cooling period ending when the [sup 3]He liquid is depleted from the mixing chamber with the mixing chamber nearly empty of liquid helium, thus avoiding unnecessary and inefficient cooling of a large amount of the dilute [sup 3]He-[sup 4]He liquid phase. 2 figs.

  14. New Regenerative Cycle for Vapor Compression Refrigeration

    Office of Scientific and Technical Information (OSTI)

    SCIENTIFIC REPORT Title Page Project Title: New Regenerative Cycle for Vapor Compression Refrigeration DOE Award Number: DE-FG36-04GO14327 Document Title: Final Scientific Report Period Covered by Report: September 30, 2004 to September 30, 2005 Name and Address of Recipient Organization: Magnetic Development, Inc., 68 Winterhill Road, Madison, CT 06443, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Contact Information: Mark J. Bergander, Ph.D., P.E., Principal Investigator,

  15. Use of magnetic carbon composites from renewable resource materials for oil spill clean up and recovery

    DOE Patents [OSTI]

    Viswanathan, Tito

    2014-02-11

    A method for separating a liquid hydrocarbon material from a body of water. In one embodiment, the method includes the steps of mixing a plurality of magnetic carbon-metal nanocomposites with a liquid hydrocarbon material dispersed in a body of water to allow the plurality of magnetic carbon-metal nanocomposites each to be adhered by an amount of the liquid hydrocarbon material to form a mixture, applying a magnetic force to the mixture to attract the plurality of magnetic carbon-metal nanocomposites each adhered by an amount of the liquid hydrocarbon material, and removing said plurality of magnetic carbon-metal nanocomposites each adhered by an amount of the liquid hydrocarbon material from said body of water while maintaining the applied magnetic force, wherein the plurality of magnetic carbon-metal nanocomposites is formed by subjecting one or more metal lignosulfonates or metal salts to microwave radiation, in presence of lignin/derivatives either in presence of alkali or a microwave absorbing material.

  16. Active magnetic regenerator

    DOE Patents [OSTI]

    Barclay, John A.; Steyert, William A.

    1982-01-01

    The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

  17. Probing nanoscale behavior of magnetic materials with soft x-ray

    Office of Scientific and Technical Information (OSTI)

    spectromicroscopy (Journal Article) | SciTech Connect Probing nanoscale behavior of magnetic materials with soft x-ray spectromicroscopy Citation Details In-Document Search Title: Probing nanoscale behavior of magnetic materials with soft x-ray spectromicroscopy Authors: Fischer, Peter ; Fadley, Charles Publication Date: 2012-07-02 OSTI Identifier: 1172970 Report Number(s): LBNL-5867E DOE Contract Number: DE-AC02-05CH11231 Resource Type: Journal Article Resource Relation: Journal Name:

  18. Cryogenic refrigeration apparatus

    DOE Patents [OSTI]

    Crunkleton, James A.

    1992-01-01

    A technique for producing a cold environment in a refrigerant system in which input fluid from a compressor at a first temperature is introduced into an input channel of the system and is pre-cooled to a second temperature for supply to one of at least two stages of the system, and to a third temperature for supply to another stage thereof. The temperatures at such stages are reduced to fourth and fifth temperatures below the second and third temperatures, respectively. Fluid at the fourth temperature from the one stage is returned through the input channel to the compressor and fluid at the fifth temperature from the other stage is returned to the compressor through an output channel so that pre-cooling of the input fluid to the one stage occurs by regenerative cooling and counterflow cooling and pre-cooling of the input fluid to the other stage occurs primarily by counterflow cooling.

  19. Cryogenic refrigeration apparatus

    DOE Patents [OSTI]

    Crunkleton, J.A.

    1992-03-31

    A technique for producing a cold environment in a refrigerant system in which input fluid from a compressor at a first temperature is introduced into an input channel of the system and is pre-cooled to a second temperature for supply to one of at least two stages of the system, and to a third temperature for supply to another stage thereof. The temperatures at such stages are reduced to fourth and fifth temperatures below the second and third temperatures, respectively. Fluid at the fourth temperature from the one stage is returned through the input channel to the compressor and fluid at the fifth temperature from the other stage is returned to the compressor through an output channel so that pre-cooling of the input fluid to the one stage occurs by regenerative cooling and counterflow cooling and pre-cooling of the input fluid to the other stage occurs primarily by counterflow cooling. 6 figs.

  20. Refrigerator-freezer energy testing with alternative refrigerants

    SciTech Connect (OSTI)

    Sand, J.R. ); Vineyard, E.A.; Sand, J.R.

    1989-01-01

    As a result of the Montreal Protocol (UNEP 1987) that limits the production of ozone-depleting refrigerants, manufacturers are searching for alternatives to replace the R12 that is presently used in residential refrigerator-freezers. Before an alternative can be selected, several issues must resolved. Among these are energy impacts, system compatibility, cost, and availability, In an effort to determine the energy impacts of some of the alternatives, energy consumption tests were performed in accordance with section 8 of the Association of Home Appliance Manufacturers (AHAM) standard for household refrigerators and household freezers (AHAM 1985). The results are presented for an 18 ft{sup 3} (0.51 m{sup 3}), top mount refrigerators-freezer with a static condenser using the following refrigerants: R 12, R500, R12/dimethylether (DME), R22/R142b, and R134a. Conclusions from the AHAM test are that R500 and R12/DME have a reduced energy consumption relative to R12 when replaced in the test unit with no modifications to the refrigeration system. Run times were slightly lower than R12 for both refrigerants, indicating a higher capacity. While the R134a and R22/R142b results were less promising (6.8% and 8.5% higher energy consumption, respectively), changes to the refrigeration system, such as a different capillary tube or compressor, may improve their performance. It is noted that the test results are only an initial step in determining a replacement for R12.

  1. Magnetocaloric Refrigerator Freezer

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Magnetic stabilization to develop 3D MCM microchannels Solid state magnetocaloric machine ... Progress and Accomplishments Accomplishments: - MCM successfully 3D printed in the form of ...

  2. Permanent magnet assembly

    DOE Patents [OSTI]

    Chell, Jeremy; Zimm, Carl B.

    2006-12-12

    A permanent magnet assembly is disclosed that is adapted to provide a magnetic field across an arc-shaped gap. Such a permanent magnet assembly can be used, for example, to provide a time-varying magnetic field to an annular region for use in a magnetic refrigerator.

  3. Using Magnets to Keep Cool: Breakthrough Technology Boosts Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficiency of Refrigerators | Department of Energy Using Magnets to Keep Cool: Breakthrough Technology Boosts Energy Efficiency of Refrigerators Using Magnets to Keep Cool: Breakthrough Technology Boosts Energy Efficiency of Refrigerators July 29, 2014 - 2:13pm Addthis Researchers demonstrate General Electric's magnetocaloric system. | Photo courtesy of General Electric Researchers demonstrate General Electric's magnetocaloric system. | Photo courtesy of General Electric Antonio Bouza

  4. Non-intrusive refrigerant charge indicator

    DOE Patents [OSTI]

    Mei, Viung C.; Chen, Fang C.; Kweller, Esher

    2005-03-22

    A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is under-charged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.

  5. Dynamic high pressure process for fabricating superconducting and permanent magnetic materials

    DOE Patents [OSTI]

    Nellis, W.J.; Geballe, T.H.; Maple, M.B.

    1990-03-13

    Shock wave formation of thin layers of materials with improved superconducting and permanent magnetic properties and improved microstructures is disclosed. The material fabrication system includes a sandwiched structure including a powder material placed between two solid members to enable explosive shock consolidation. The two solid members are precooled to about 80--100 K to reduce the residual temperatures attained as a result of the shock wave treatment, and thereby increase the quench rate of the consolidated powder. 9 figs.

  6. Dynamic high pressure process for fabricating superconducting and permanent magnetic materials

    DOE Patents [OSTI]

    Nellis, William J.; Geballe, Theodore H.; Maple, M. Brian

    1990-01-01

    Shock wave formation of thin layers of materials with improved superconducting and permanent magnetic properties and improved microstructures. The material fabrication system includes a sandwiched structure including a powder material placed between two solid members to enable explosive shock consolidation. The two solid members are precooled to about 80.degree.-100.degree. K. to reduce the residual temperatures attained as a result of the shock wave treatment, and thereby increase the quench rate of the consolidated powder.

  7. Ion energy-angle distribution functions at the plasma-material interface in oblique magnetic fields

    SciTech Connect (OSTI)

    Khaziev, Rinat; Curreli, Davide

    2015-04-15

    The ion energy-angle distribution (IEAD) at the wall of a magnetized plasma is of fundamental importance for the determination of the material processes occurring at the plasma-material interface, comprising secondary emissions and material sputtering. Here, we present a numerical characterization of the IEAD at the wall of a weakly collisional magnetized plasma with the magnetic field inclined at an arbitrary angle with respect to the wall. The analysis has been done using two different techniques: (1) a fluid-Monte Carlo method, and (2) particle-in-cell simulations, the former offering a fast but approximate method for the determination of the IEADs, the latter giving a computationally intensive but self-consistent treatment of the plasma behavior from the quasi-neutral region to the material boundary. The two models predict similar IEADs, whose similarities and differences are discussed. Data are presented for magnetic fields inclined at angles from normal to grazing incidence (0°–85°). We show the scaling factors of the average and peak ion energy and trends of the pitch angle at the wall as a function of the magnetic angle, for use in the correlation of fluid plasma models to material models.

  8. THERMAL IMAGING OF ACTIVE MAGNETIC REGERNERATOR MCE MATERIALS DURING OPERATION

    SciTech Connect (OSTI)

    Shassere, Benjamin [ORNL] [ORNL; West, David L [ORNL] [ORNL; Abdelaziz, Omar [ORNL] [ORNL; Evans III, Boyd Mccutchen [ORNL] [ORNL

    2012-01-01

    An active magnetic regenerator (AMR) prototype was constructed that incorporates a Gd sheet into the regenerator wall to enable visualization of the system s thermal transients. In this experiment, the thermal conditions inside the AMR are observed under a variety of operating conditions. An infrared (IR) camera is employed to visualize the thermal transients within the AMR. The IR camera is used to visually and quantitatively evaluate the temperature difference and thus giving means to calculate the performance of the system under the various operating conditions. Thermal imaging results are presented for two differing experimental test runs. Real time imaging of the thermal state of the AMR has been conducted while operating the system over a range of conditions. A 1 Tesla twin-coil electromagnet (situated on a C frame base) is used for this experiment such that all components are stationary during testing. A modular, linear reciprocating system has been realized in which the effects of regenerator porosity and utilization factor can be investigated. To evaluate the performance variation in porosity and utilization factor the AMR housing was constructed such that the plate spacing of the Gd sheets may be varied. Each Gd sheet has dimensions of 38 mm wide and 66 mm long with a thickness of 1 mm and the regenerator can hold a maximum of 29 plates with a spacing of 0.25 mm. Quantitative and thermal imaging results are presented for several regenerator configurations.

  9. Use of High Magnetic Fields to Improve Material Properties for Hydraulics, Automotive and Truck Components

    SciTech Connect (OSTI)

    Ludtka, Gerard Michael; Ludtka, Gail Mackiewicz-; Wilgen, John B; Kisner, Roger A; Ahmad, Aquil

    2010-08-01

    In this CRADA, research and development activities were successfully conducted on magnetic processing effects for the purpose of manipulating microstructure and the application specific performance of three alloys provided by Eaton (alloys provided were: carburized steel, plain low carbon steel and medium carbon spring steel). Three specific industrial/commercial application areas were considered where HMFP can be used to provide significant energy savings and improve materials performance include using HMFP to: 1.) Produce higher material strengths enabling higher torque bearing capability for drive shafts and other motor components; 2.) Increase the magnetic response in an iron-based material, thereby improving its magnetic permeability resulting in improved magnetic coupling and power density, and 3.) Improve wear resistance. The very promising results achieved in this endeavor include: 1.) a significant increase in tensile strength and a major reduction in volume percent retained austenite for the carburized alloy, and 2.) a substantial improvement in magnetic perm respect to a no-field processed sample (which also represents a significant improvement over the nominal conventional automotive condition of no heat treatment). The successful completion of these activities has resulted in the current 3-year CRADA No. NFE-09-02522 Prototyping Energy Efficient ThermoMagnetic and Induction Hardening for Heat Treat and Net Shape Forming Applications .

  10. Thermal effects on transducer material for heat assisted magnetic recording application

    SciTech Connect (OSTI)

    Ji, Rong Xu, Baoxi; Cen, Zhanhong; Ying, Ji Feng; Toh, Yeow Teck

    2015-05-07

    Heat Assisted Magnetic Recording (HAMR) is a promising technology for next generation hard disk drives with significantly increased data recording capacities. In HAMR, an optical near-field transducer (NFT) is used to concentrate laser energy on a magnetic recording medium to fulfill the heat assist function. The key components of a NFT are transducer material, cladding material, and adhesion material between the cladding and the transducer materials. Since transducer materials and cladding materials have been widely reported, this paper focuses on the adhesion materials between the Au transducer and the Al{sub 2}O{sub 3} cladding material. A comparative study for two kinds of adhesion material, Ta and Cr, has been conducted. We found that Ta provides better thermal stability to the whole transducer than Cr. This is because after thermal annealing, chromium forms oxide material at interfaces and chromium atoms diffuse remarkably into the Au layer and react with Au to form Au alloy. This study also provides insights on the selection of adhesion material for HAMR transducer.

  11. High Efficiency Motors for Refrigerated Open Display Cases

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    with support from commercial refrigeration OEMs, retrofit contractors, utilities ... from commercial refrigeration OEMs, retrofit contractors, utilities and grocery sites. ...

  12. Exploring nanoscale magnetism in advanced materials with polarized X-rays

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Exploring nanoscale magnetism in advanced materials with polarized X-rays Citation Details In-Document Search Title: Exploring nanoscale magnetism in advanced materials with polarized X-rays No abstract prepared. Authors: Fischer, Peter Publication Date: 2011-05-01 OSTI Identifier: 1051277 Report Number(s): LBNL-5104E Journal ID: ISSN 0927-796X; MIGIEA; TRN: US201218%%1364 DOE Contract Number: DE-AC02-05CH11231 Resource Type: Journal Article Resource

  13. Disorder-Induced Microscopic Magnetic Memory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    point for future theories. The Persistence of Memory Magnets are not just for refrigerator doors-they are of paramount importance in today's digital information age. In the...

  14. Everest Refrigeration: Noncompliance Determination (2015-SE-42001)

    Broader source: Energy.gov [DOE]

    DOE issued a Notice of Noncompliance Determination to Bu Sung America Corporation (dba Everest Refrigeration) finding that commercial refrigeration equipment model number ESGR3 does not comport with the energy conservation standards.

  15. Thermoelectric refrigerator having improved temperature stabilization means

    DOE Patents [OSTI]

    Falco, Charles M.

    1982-01-01

    A control system for thermoelectric refrigerators is disclosed. The thermoelectric refrigerator includes at least one thermoelectric element that undergoes a first order change at a predetermined critical temperature. The element functions as a thermoelectric refrigerator element above the critical temperature, but discontinuously ceases to function as a thermoelectric refrigerator element below the critical temperature. One example of such an arrangement includes thermoelectric refrigerator elements which are superconductors. The transition temperature of one of the superconductor elements is selected as the temperature control point of the refrigerator. When the refrigerator attempts to cool below the point, the metals become superconductors losing their ability to perform as a thermoelectric refrigerator. An extremely accurate, first-order control is realized.

  16. Refrigerator Manufacturers: Order (2013-CE-5341)

    Broader source: Energy.gov [DOE]

    DOE ordered Refrigerator Manufacturers, LLC to pay a $8,000 civil penalty after finding Refrigerator Manufacturers had failed to certify that certain models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  17. Cospolich Refrigerator: Order (2013-CE-5314)

    Broader source: Energy.gov [DOE]

    DOE ordered Cospolich Refrigerator Co, Inc. to pay a $8,000 civil penalty after finding Cospolich Refrigerator had failed to certify that certain models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  18. Refrigeration system having dual suction port compressor

    DOE Patents [OSTI]

    Wu, Guolian

    2016-01-05

    A cooling system for appliances, air conditioners, and other spaces includes a compressor, and a condenser that receives refrigerant from the compressor. The system also includes an evaporator that receives refrigerant from the condenser. Refrigerant received from the condenser flows through an upstream portion of the evaporator. A first portion of the refrigerant flows to the compressor without passing through a downstream portion of the evaporator, and a second portion of the refrigerant from the upstream portion of the condenser flows through the downstream portion of the evaporator after passing through the upstream portion of the evaporator. The second portion of the refrigerant flows to the compressor after passing through the downstream portion of the evaporator. The refrigeration system may be configured to cool an appliance such as a refrigerator and/or freezer, or it may be utilized in air conditioners for buildings, motor vehicles, or other such spaces.

  19. Everest Refrigeration: Proposed Penalty (2015-SE-42001)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Bu Sung America Corporation (dba Everest Refrigeration) manufactured and distributed noncompliant commercial refrigeration equipment model ESGR3 in the U.S.

  20. International Refrigeration: Order (2012-CE-1510)

    Broader source: Energy.gov [DOE]

    DOE ordered International Refrigeration Products to pay an $8,000 civil penalty after finding International Refrigeration had failed to certify that certain room air conditioners comply with the applicable energy conservation standard.

  1. High magnetic-refrigeration performance of plate-shaped La{sub 0.5}Pr{sub 0.5}Fe{sub 11.4}Si{sub 1.6} hydrides sintered in high-pressure H{sub 2} atmosphere

    SciTech Connect (OSTI)

    Sun, N. K. Guo, J.; Zhao, X. G. Zhang, Z. D.; Si, P. Z.; Huang, J. H.

    2015-03-02

    La(Fe, Si){sub 13} hydride is regarded as one of the most promising room-temperature refrigerants. However, to use the alloys in an active magnetic regenerator machine, it is vital to prepare thin refrigerants. In this work, a high H{sub 2} gas pressure of 50 MPa was employed to suppress the desorption of hydrogen atoms during the sintering process of plate-shaped La{sub 0.5}Pr{sub 0.5}Fe{sub 11.4}Si{sub 1.6} hydrides. At 330 K, a high-density sintered thin plate shows a large magnetic-entropy change ΔS{sub m} of 15.5 J/kg K (106 mJ/cm{sup 3 }K) for a field change of 2 T. The volumetric ΔS{sub m} is almost twice as large as that of bonded La(Fe,Si){sub 13} hydrides. Favorably, hysteresis is almost absent due to the existence of micropores with a porosity of 0.69% which has been analyzed with high-resolution X-ray microtomography.

  2. Room temperature magnetocaloric effect and refrigerant capacitance in La{sub 0.7}Sr{sub 0.3}MnO{sub 3} nanotube arrays

    SciTech Connect (OSTI)

    Kumaresavanji, M. Sousa, C. T.; Pires, A.; Pereira, A. M.; Araujo, J. P.; Lopes, A. M. L.

    2014-08-25

    High aspect ratio La{sub 0.7}Sr{sub 0.3}MnO{sub 3} nanotube (NT) arrays have been synthesized using nitrates based sol-gel precursor by nanoporous anodized aluminum oxide template assisted method. Their phase purity and microstructures were analyzed by X-ray diffraction, scanning electron microscopy, and energy-dispersive x-ray spectroscopy. Magnetocaloric effect (MCE) of as prepared NTs was investigated by means of field dependence magnetization measurements. Significant magnetic entropy change, −△S{sub M} = 1.6 J/kg K, and the refrigerant capacitance, RC = 69 J/kg, were achieved near the transition temperature at 315 K for 5 T. For comparison, a bulk sample was also prepared using the same precursor solution which gives a value of −△S{sub M} = 4.2 J/kg K and a RC = 165 J/kg. Though the bulk sample exhibits higher △S{sub M} value, the NTs present an expanded temperature dependence of −△S{sub M} curves that spread over a broad temperature range and assured to be appropriate for active magnetic refrigeration. The diminutive MCE observed in manganite NTs is explained by the increased influence of surface sites of nanograins which affect the structural phase transition occurred by external magnetic field due to the coupling between magnetism and the lattice in manganese perovskites. Our report paves the way for further investigation in 1D manganite nanostructured materials towards applications in such magnetic refrigeration technology or even on hyperthermia/drug delivery.

  3. Method and apparatus for desuperheating refrigerant

    DOE Patents [OSTI]

    Zess, James A.; Drost, M. Kevin; Call, Charles J.

    1997-01-01

    The present invention is an apparatus and method for de-superheating a primary refrigerant leaving a compressor wherein a secondary refrigerant is used between the primary refrigerant to be de-superheated. Reject heat is advantageously used for heat reclaim.

  4. Electronic & magnetic materials and devices at the CNM | Argonne National

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory Electronic & magnetic materials and devices at the CNM Graphene Micrograph 1 of 24 Graphene Micrograph Ultra-high vacuum scanning tunneling microscopy image of a point defect in graphene that has been epitaxially grown on 6H-SiC(0001) (Nathan Guisinger, EMMD Group) at Argonne's Center for Nanoscale Materials. Image: Photo courtesy of Argonne National Laboratory Graphene Micrograph 1 of 24 Graphene Micrograph Ultra-high vacuum scanning tunneling microscopy image of a point

  5. Modeling and Characterization of the Magnetocaloric Effect in Ni2MnGa Materials

    SciTech Connect (OSTI)

    Nicholson, Don M; Odbadrakh, Khorgolkhuu; Shassere, Benjamin; Rios, Orlando; Hodges, Jason P; Ludtka, Gerard Michael; Porter, Wallace D; Safa-Sefat, Athena; Rusanu, Aurelian; Brown, Greg; Evans III, Boyd Mccutchen

    2014-01-01

    Magnetic shape memory alloys have great promise as magneto-caloric effect refrigerant materials due to their combined magnetic and structural transitions. Computational and experimental research is reported on the Ni2MnGa material system. The magnetic states of this system are explored using the Wang-Landau statistical approach in conjunction with the Locally Self-consistent Multiple-Scattering method. The effects of alloying agents on the transition temperatures of the Ni2MnGa alloy are investigated using differential scanning calorimetry and superconducting quantum interference device. Experiments are performed at the Spallation Neutron Source at Oak Ridge National Laboratory to observe the structural and magnetic phase transformations.

  6. Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials

    DOE Patents [OSTI]

    Matlashov, Andrei Nikolaevich; Urbaitis, Algis V.; Savukov, Igor Mykhaylovich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry

    2013-03-05

    Method comprising obtaining an NMR measurement from a sample wherein an ultra-low field NMR system probes the sample and produces the NMR measurement and wherein a sampling temperature, prepolarizing field, and measurement field are known; detecting the NMR measurement by means of inductive coils; analyzing the NMR measurement to obtain at least one measurement feature wherein the measurement feature comprises T1, T2, T1.rho., or the frequency dependence thereof; and, searching for the at least one measurement feature within a database comprising NMR reference data for at least one material to determine if the sample comprises a material of interest.

  7. A recuperative superfluid stirling refrigerator

    SciTech Connect (OSTI)

    Brisson, J.G.; Swift, G.W.

    1993-07-01

    A superfluid Stirling refrigerator has been built with a counterflow heat exchanger serving as a recuperative regenerator. It has achieved temperatures of 296 mK with a 4% {sup 3}He-{sup 4}He mixture. Cooling power versus temperature and speed is presented for a 6.6% mixture.

  8. Overview of Air Liquide refrigeration systems between 1.8 K and 200 K

    SciTech Connect (OSTI)

    Gondrand, C.; Durand, F.; Delcayre, F.; Crispel, S.; Baguer, G. M. Gistau

    2014-01-29

    Cryogenic refrigeration systems are necessary for numerous applications. Gas purification and distillation require temperatures between 15 K and 200 K depending on the application, space simulation chambers down to 15 K, superconductivity between 1.8 K and up to 75 K (magnets, cavities or HTS devices like cables, FCL, SMES, etc), Cold Neutron Sources between 15 and 20 K, etc. Air Liquide Advanced Technologies is designing and manufacturing refrigerators since 60 years to satisfy those needs. The step by step developments achieved have led to machines with higher efficiency and reliability. In 1965, reciprocating compressors and Joule Thomson expansion valves were used. In 1969, centripetal expanders began to be used. In 1980, oil lubricated screw compressors took the place of reciprocating compressors and a standard range of Claude cycle refrigerators was developed: the HELIAL series. 1980 was also the time for cryogenic centrifugal compressor development. In 2011, driven by the need for lower operational cost (high efficiency and low maintenance), cycle oil free centrifugal compressors on magnetic bearings were introduced instead of screw compressors. The power extracted by centripetal expanders was recovered. Based on this technology, a range of Turbo-Brayton refrigerators has been designed for temperatures between 40 K and 150 K. On-going development will enable widening the range of Turbo-Brayton refrigerators to cryogenic temperatures down to 15 K.. Cryogenic centrifugal circulators have been developed in order to answer to an increasing demand of 4 K refrigerators able to distribute cold power.

  9. Dry demagnetization cryostat for sub-millikelvin helium experiments: Refrigeration and thermometry

    SciTech Connect (OSTI)

    Todoshchenko, I. Kaikkonen, J.-P.; Hakonen, P. J.; Savin, A.; Blaauwgeers, R.

    2014-08-01

    We demonstrate successful “dry” refrigeration of quantum fluids down to T = 0.16 mK by using copper nuclear demagnetization stage that is pre-cooled by a pulse-tube-based dilution refrigerator. This type of refrigeration delivers a flexible and simple sub-mK solution to a variety of needs including experiments with superfluid {sup 3}He. Our central design principle was to eliminate relative vibrations between the high-field magnet and the nuclear refrigeration stage, which resulted in the minimum heat leak of Q = 4.4 nW obtained in field of 35 mT. For thermometry, we employed a quartz tuning fork immersed into liquid {sup 3}He. We show that the fork oscillator can be considered as self-calibrating in superfluid {sup 3}He at the crossover point from hydrodynamic into ballistic quasiparticle regime.

  10. Effects of temperature on desiccant catalysis of refrigerant and lubricant decomposition. Final report

    SciTech Connect (OSTI)

    Rohatgi, N.D.T.

    1998-06-01

    Accelerated aging at high temperatures (149 C) for short aging times (28 days) is effective in screening the compatibility of different materials in refrigeration systems. However, in actual applications temperatures are usually lower and operating times much longer. Therefore plots to allow for interpolation or extrapolation of experimental data to actual operating conditions are needed. In the current study, aging of refrigerant/lubricant/desiccant/metal systems was conducted at five different temperatures, and for each temperature at four different aging times. The data collected from this study provided plots relating refrigerant or lubricant decomposition to aging time, aging temperature, and type of desiccant, which can be used for interpolation or extrapolation.

  11. System and method for non-destructive evaluation of surface characteristics of a magnetic material

    DOE Patents [OSTI]

    Jiles, David C.; Sipahi, Levent B.

    1994-05-17

    A system and a related method for non-destructive evaluation of the surface characteristics of a magnetic material. The sample is excited by an alternating magnetic field. The field frequency, amplitude and offset are controlled according to a predetermined protocol. The Barkhausen response of the sample is detected for the various fields and offsets and is analyzed. The system produces information relating to the frequency content, the amplitude content, the average or RMS energy content, as well as count rate information, for each of the Barkhausen responses at each of the excitation levels applied during the protocol. That information provides a contiguous body of data, heretofore unavailable, which can be analyzed to deduce information about the surface characteristics of the material at various depths below the surface.

  12. Miniaturized Air to Refrigerant Heat Exchangers

    Broader source: Energy.gov [DOE]

    This project is developing a miniaturized air-to-refrigerant heat exchanger that is more compact and more energy efficient than current market designs. The heat exchanger will feature at least 20% less volume, material volume, and approach temperature compared to current multiport flat tube designs, and it will be in production within five years. The heat exchanger, which acts as both an evaporator and a condenser, can be applied to commercial and residential air-conditioning or heat pump systems with various capacity scales. Prototype 1-kilowatt (kW) and 10 kW designs will be tested and then improved as necessary for final tests and demonstration in a 3-ton heat pump.

  13. Energy Efficient Commercial Refrigeration with Carbon Dioxide Refrigerant and Scroll Expanders

    SciTech Connect (OSTI)

    Dieckmann, John

    2013-04-04

    Current supermarket refrigeration systems are built around conventional fluorocarbon refrigerants – HFC-134a and the HFC blends R-507 and R404A, which replaced the CFC refrigerants, R-12 and R-502, respectively, used prior to the Montreal Protocol phase out of ozone depleting substances. While the HFC refrigerants are non-ozone depleting, they are strong greenhouse gases, so there has been continued interest in replacing them, particularly in applications with above average refrigerant leakage. Large supermarket refrigeration systems have proven to be particularly difficult to maintain in a leak-tight condition. Refrigerant charge losses of 15% of total charge per year are the norm, making the global warming impact of refrigerant emissions comparable to that associated with the energy consumption of these systems.

  14. CRYOGENIC MAGNETS

    DOE Patents [OSTI]

    Post, R.F.; Taylor, C.E.

    1963-05-21

    A cryogenic magnet coil is described for generating magnetic fields of the order of 100,000 gauss with a minimum expenditure of energy lost in resistive heating of the coil inductors and energy lost irreversibly in running the coil refrigeration plant. The cryogenic coil comprises a coil conductor for generating a magnetic field upon energization with electrical current, and refrigeration means disposed in heat conductive relation to the coil conductor for cooling to a low temperature. A substantial reduction in the power requirements for generating these magnetic fields is attained by scaling the field generating coil to large size and particular dimensions for a particular conductor, and operating the coil at a particular optimum temperature commensurate with minimum overall power requirements. (AEC)

  15. Cryogenics for superconductors: Refrigeration, delivery, and preservation of the cold

    SciTech Connect (OSTI)

    Venkatarao Ganni, James Fesmire

    2012-06-01

    Applications in superconductivity have become widespread, enabled by advancements in cryogenic engineering. In this paper, the history of cryogenic refrigeration, its delivery, its preservation and the important scientific and engineering advancements in these areas in the last 100 years will be reviewed, beginning with small laboratory dewars to very large scale systems. The key technological advancements in these areas that enabled the development of superconducting applications at temperatures from 4 to 77 K are identified. Included are advancements in the components used up to the present state-of-the-art in refrigeration systems design. Viewpoints as both an equipment supplier and the end-user with regard to the equipment design and operations will be presented. Some of the present and future challenges in these areas will be outlined. Most of the materials in this paper are a collection of the historical materials applicable to these areas of interest.

  16. Covered Product Category: Commercial Refrigerators and Freezers

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Federal Energy Management Program (FEMP) provides acquisition guidance for commercial refrigerators and freezers, which are covered by the ENERGY STAR program.

  17. Working Fluids Low Global Warming Potential Refrigerants

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    to achieve these goals - Provide guidance to the HVAC&R community on selecting alternative, energy-efficient, low GWP refrigerants - Enable U.S. manufacturers to position ...

  18. Natural Refrigerant (R-729) Heat Pump

    Broader source: Energy.gov (indexed) [DOE]

    Natural Refrigerant (R-729) Heat Pump 2014 Building Technologies Office Peer Review New Project Lee Jestings (lee@S-RAM.com), Project Summary Timeline: Key Partners: Start date:...

  19. Miniaturized Air to Refrigerant Heat Exchangers | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    in ORNL's Building Technologies Research & Integration Center. Working Fluids Low Global Warming Potential Refrigerants Improving Data Center Efficiency with Rack or Row...

  20. Air Conditioning Heating and Refrigeration Institute Comment...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    PDF icon DOE Reg Burden RFI 7-18-14 More Documents & Publications Regulatory Burden RFI from AHRI Regulatory Burden RFI Air-Conditioning, Heating, and Refrigeration Institute ...

  1. Tokamak Physics EXperiment (TPX): Toroidal field magnet design, development and manufacture. SDRL 21, Materials and processes selection. Volume 2

    SciTech Connect (OSTI)

    Smith, B.R.

    1995-08-15

    This document identifies the candidate materials and manufacturing processes selected for development of the TPX Toroidal Field (TF) Magnet. Supporting rationale and selection criteria are provided for justification and the materials properties database report is included for completeness. Specific properties for each material selection are included in this document.

  2. Effect of Composition and Heat Treatment on MnBi Magnetic Materials

    SciTech Connect (OSTI)

    Cui, Jun; Choi, Jung-Pyung; Polikarpov, Evgueni; Bowden, Mark E.; Xie, Wei; Li, Guosheng; Nie, Zimin; Zarkevich, Nikolai; Kramer, Matthew J.; Johnson, Duane D.

    2014-08-17

    The metallic compound MnBi is a promising rare-earth-free permanent magnet material. Compare to other rare-earth-free candidates, MnBi stands out for its high intrinsic coercivity (Hci) and its large positive temperature coefficient. Several groups have demonstrated that the Hci of MnBi compound in thin film or in powder form can exceed 12 kOe and 26 kOe at 300 K and 523 K, respectively. Such steep increase in Hci with increasing temperature is unique to MnBi. Consequently, MnBi is a highly sought-after hard phase for exchange coupling nanocomposite magnets. The reaction between Mn and Bi is peritectic, so Mn tends to precipitate out of the MnBi liquid during the solidification process. As result, the composition of the Mn-Bi alloy with the largest amount of the desired LTP (low temperature phase) MnBi and highest saturation magnetization will be over-stoichiometric and rich in Mn. The amount of additional Mn required to compensate the Mn precipitation depends on solidification rate: the faster the quench speed, the less Mn precipitates. Here we report a systematic study of the effect of composition and heat treatments on the phase contents and magnetic properties of Mn-Bi alloys. In this study, Mn-Bi alloys with 14 compositions were prepared using conventional metallurgical methods such as arc melting and vacuum heat treatment, and the obtained alloys were analyzed for compositions, crystal structures, phase content, and magnetic properties. The results show that the composition with 55 at.% Mn exhibits the highest LTP MnBi content and the highest magnetization. The sample with this composition shows >90 wt.% LTP MnBi content. Its measured saturation magnetization is 68 emu/g with 2.3 T applied field at 300 K; its coercivity is 13 kOe and its energy product is 12 MGOe at 300 K. A bulk magnet fabricated using this powder exhibits an energy product of 8.2 MGOe.

  3. Ex Parte Communication_Kitable Refrigerator/Freezer Guidance...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    CommunicationKitable RefrigeratorFreezer Guidance Ex Parte CommunicationKitable RefrigeratorFreezer Guidance This memo memorializes the meeting between AHAM and the Department ...

  4. Thermoacoustic Engines and Refrigerators: A Short Course (Conference...

    Office of Scientific and Technical Information (OSTI)

    Thermoacoustic Engines and Refrigerators: A Short Course Citation Details In-Document Search Title: Thermoacoustic Engines and Refrigerators: A Short Course You are accessing a ...

  5. Product Standards for Refrigerators (Japan) | Open Energy Information

    Open Energy Info (EERE)

    Refrigerators (Japan) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Product Standards for Refrigerators (Japan) Focus Area: Appliances & Equipment Topics: Policy...

  6. American Society of Heating, Refrigeration, and Air Condition...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    American Society of Heating, Refrigeration, and Air Condition Engineers (ASHRAE) 2016 Annual Conference American Society of Heating, Refrigeration, and Air Condition Engineers ...

  7. 2014-04-10 Issuance: Test Procedures for Commercial Refrigeration...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    0 Issuance: Test Procedures for Commercial Refrigeration Equipment; Final Rule 2014-04-10 Issuance: Test Procedures for Commercial Refrigeration Equipment; Final Rule This document ...

  8. 2014-11-26 Issuance: Test Procedures for Miscellaneous Refrigeration...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    6 Issuance: Test Procedures for Miscellaneous Refrigeration Products; Notice of Proposed Rulemaking 2014-11-26 Issuance: Test Procedures for Miscellaneous Refrigeration Products; ...

  9. 2014-08-01 Issuance: Test Procedure for Refrigerated Bottled...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Test Procedure for Refrigerated Bottled or Canned Beverage Vending Machines; Notice of Proposed Rulemaking and public meeting 2014-08-01 Issuance: Test Procedure for Refrigerated ...

  10. Energy Efficiency Standards for Refrigerators in Brazil: A Methodology...

    Open Energy Info (EERE)

    Standards for Refrigerators in Brazil: A Methodology for Impact Evaluation Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Energy Efficiency Standards for Refrigerators...

  11. Unified HVAC and Refrigeration Control Systems for Small Footprint...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    refrigeration systems and integrate photovoltaic sources Key Issues: Low-cost, "low-touch" retrofit of control technology into buildings and refrigeration systems to facilitate ...

  12. CBEI: Virtual Refrigerant Charge Sensing and Load Metering -...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Virtual Refrigerant Charge Sensing and Load Metering - 2015 Peer Review CBEI: Virtual Refrigerant Charge Sensing and Load Metering - 2015 Peer Review Presenter: James Braun, Purdue ...

  13. WPN 00-5: Approval of Replacement Refrigerators and Electric...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Provides states with the approval to include refrigerator and electric water heater replacements as an allowable measure. PDF icon WPN 00-5: Approval of Replacement Refrigerators ...

  14. Ames Lab-based consortium to research improving refrigeration...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ames Lab-based consortium to research improving refrigeration technology Ames Tribune ... alternative environmentally-friendly and energy- efficient technologies in refrigeration. ...

  15. Ames Laboratory to lead new consortium to advance refrigeration...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory to lead new consortium to advance refrigeration technology Ames Laboratory will ... friendly and energy-efficient refrigeration technologies, sponsored by DOE's ...

  16. HEATING, AIR-CONDITIONING AND REFRIGERATION DISTRIBUTORS INTERNATIONAL...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    HEATING, AIR-CONDITIONING AND REFRIGERATION DISTRIBUTORS INTERNATIONAL (HARDI) HEATING, AIR-CONDITIONING AND REFRIGERATION DISTRIBUTORS INTERNATIONAL (HARDI) OE Framework Document ...

  17. 2016 American Society of Heating, Refrigerating, and Air-Conditioning...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2016 American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) Winter Conference 2016 American Society of Heating, Refrigerating, and Air-Conditioning...

  18. DOE Testing Reveals Samsung Refrigerator Does Not Meet Energy...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Reveals Samsung Refrigerator Does Not Meet Energy Star Requirements DOE Testing Reveals Samsung Refrigerator Does Not Meet Energy Star Requirements March 16, 2010 - 4:28pm Addthis...

  19. Alternative Refrigerant Evaluation for High-Ambient-Temperature...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments Performance of alternative ...

  20. Seven-effect absorption refrigeration

    DOE Patents [OSTI]

    DeVault, R.C.; Biermann, W.J.

    1989-05-09

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit. 1 fig.

  1. Seven-effect absorption refrigeration

    DOE Patents [OSTI]

    DeVault, Robert C.; Biermann, Wendell J.

    1989-01-01

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit.

  2. Effect of composition and heat treatment on MnBi magnetic materials

    SciTech Connect (OSTI)

    Cui, Jun [Pacific Northwest National Laboratory; Choi, Jung-Pyung [Pacific Northwest National Laboratory; Polikarpov, Evgueni [Pacific Northwest National Laboratory; Bowden, Mark E [Pacific Northwest National Laboratory; Xie, Wei [Pacific Northwest National Laboratory; Li, Guosheng [Pacific Northwest National Laboratory; Nie, Zimin [Pacific Northwest National Laboratory; Zarkevich, Nikolai [Ames Laboratory; Kramer, Matthew J [Ames Laboratory; Johnson, Duane [Ames Laboratory

    2014-10-01

    The metallic compound MnBi is a promising rare-earth-free permanent magnet material, unique among all candidates for its high intrinsic coercivity (Hci) and its large positive temperature coefficient. The Hci of MnBi in thin-film or powder form can exceed 12 and 26 kOe at 300 and 523 K, respectively. Such a steep rise in Hci with increasing temperature is unique to MnBi. Consequently, MnBi is a highly sought-after hard phase for exchange coupling nanocomposite magnets. However, the reaction between Mn and Bi is peritectic, and hence Mn tends to precipitate out of the MnBi liquid during the solidification process. As result, when the alloy is prepared using conventional induction or arc-melting casting methods, additional Mn is required to compensate the precipitation of Mn. In addition to composition, post-casting annealing plays an important role in obtaining a high content of MnBi low-temperature phase (LTP) because the annealing encourages the Mn precipitates and the unreacted Bi to react, forming the desired LTP phase. Here we report a systematic study of the effect of composition and heat treatments on the phase content and magnetic properties of MnBi alloys. In this study, 14 compositions were prepared using conventional metallurgical methods, and the compositions, crystal structures, phase content and magnetic properties of the resulting alloys were analyzed. The results show that the composition with 55 at.% Mn exhibits both the highest LTP content (93 wt.%) and magnetization (74 emu g?1 with 9 T applied field at 300 K).

  3. Magnetocaloric Refrigerator/Freezer | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Magnetocaloric Refrigerator/Freezer Magnetocaloric Refrigerator/Freezer Researchers demonstrate General Electric's magnetocaloric system. <br /> Photo courtesy of General Electric Researchers demonstrate General Electric's magnetocaloric system. Photo courtesy of General Electric Researchers demonstrate General Electric's magnetocaloric system. <br /> Photo courtesy of General Electric Lead Performer: Oak Ridge National Laboratory - Oak Ridge, TN Partner: General Electric -

  4. Commercial Refrigerator Door: Order (2013-CE-5351)

    Broader source: Energy.gov [DOE]

    DOE ordered Commercial Refrigerator Door Company, Inc. to pay a $8,000 civil penalty after finding Commercial Refrigerator Door had failed to certify that a variety of models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  5. Thermoacoustic refrigerators and engines comprising cascading stirling

    Office of Scientific and Technical Information (OSTI)

    thermodynamic units (Patent) | DOEPatents Thermoacoustic refrigerators and engines comprising cascading stirling thermodynamic units Title: Thermoacoustic refrigerators and engines comprising cascading stirling thermodynamic units The present invention includes a thermoacoustic assembly and method for improved efficiency. The assembly has a first stage Stirling thermal unit comprising a main ambient heat exchanger, a regenerator and at least one additional heat exchanger. The first stage

  6. Duracold Refrigeration Manufacturing: Order (2013-CE-5342)

    Broader source: Energy.gov [DOE]

    DOE ordered Duracold Refrigeration Manufacturing Company, LLC to pay a $8,000 civil penalty after finding Duracold Refrigeration Manufacturing had failed to certify that certain models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  7. North Star Refrigerator: Order (2013-CE-5355)

    Broader source: Energy.gov [DOE]

    DOE ordered North Star Refrigerator Co., Inc. to pay a $8,000 civil penalty after finding North Star Refrigerator had failed to certify that any basic models of walk-in cooler and freezer components comply with the applicable energy conservation standards.

  8. Counterflow absorber for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C.

    1984-01-01

    An air-cooled, vertical tube absorber for an absorption refrigeration system is disclosed. Strong absorbent solution is supplied to the top of the absorber and refrigerant vapor is supplied to the bottom of the absorber to create a direct counterflow of refrigerant vapor and absorbent solution in the absorber. The refrigeration system is designed so that the volume flow rate of refrigerant vapor in the tubes of the absorber is sufficient to create a substantially direct counterflow along the entire length of each tube in the absorber. This provides several advantages for the absorber such as higher efficiency and improved heat transfer characteristics, and allows improved purging of non-condensibles from the absorber.

  9. Oil cooled, hermetic refrigerant compressor

    DOE Patents [OSTI]

    English, William A.; Young, Robert R.

    1985-01-01

    A hermetic refrigerant compressor having an electric motor and compressor assembly in a hermetic shell is cooled by oil which is first cooled in an external cooler 18 and is then delivered through the shell to the top of the motor rotor 24 where most of it is flung radially outwardly within the confined space provided by the cap 50 which channels the flow of most of the oil around the top of the stator 26 and then out to a multiplicity of holes 52 to flow down to the sump and provide further cooling of the motor and compressor. Part of the oil descends internally of the motor to the annular chamber 58 to provide oil cooling of the lower part of the motor, with this oil exiting through vent hole 62 also to the sump. Suction gas with entrained oil and liquid refrigerant therein is delivered to an oil separator 68 from which the suction gas passes by a confined path in pipe 66 to the suction plenum 64 and the separated oil drops from the separator to the sump. By providing the oil cooling of the parts, the suction gas is not used for cooling purposes and accordingly increase in superheat is substantially avoided in the passage of the suction gas through the shell to the suction plenum 64.

  10. Oil cooled, hermetic refrigerant compressor

    DOE Patents [OSTI]

    English, W.A.; Young, R.R.

    1985-05-14

    A hermetic refrigerant compressor having an electric motor and compressor assembly in a hermetic shell is cooled by oil which is first cooled in an external cooler and is then delivered through the shell to the top of the motor rotor where most of it is flung radially outwardly within the confined space provided by the cap which channels the flow of most of the oil around the top of the stator and then out to a multiplicity of holes to flow down to the sump and provide further cooling of the motor and compressor. Part of the oil descends internally of the motor to the annular chamber to provide oil cooling of the lower part of the motor, with this oil exiting through vent hole also to the sump. Suction gas with entrained oil and liquid refrigerant therein is delivered to an oil separator from which the suction gas passes by a confined path in pipe to the suction plenum and the separated oil drops from the separator to the sump. By providing the oil cooling of the parts, the suction gas is not used for cooling purposes and accordingly increase in superheat is substantially avoided in the passage of the suction gas through the shell to the suction plenum. 3 figs.

  11. Modeling and Characterization of the Magnetocaloric Effect in Ni2MnGa Materials

    SciTech Connect (OSTI)

    Nicholson, Don M; Odbadrakh, Khorgolkhuu; Rios, Orlando; Hodges, Jason P; Ludtka, Gerard Michael; Porter, Wallace D; Sefat, A. S.; Rusanu, Aurelian; Evans III, Boyd Mccutchen

    2012-01-01

    Magnetic shape memory alloys have great promise as magneto-caloric effect refrigerant materials due to their combined magnetic and structural transitions. Computational and experimental research is reported on the Ni2MnGa material system. The magnetic states of this system have been explored using the Wang-Landau statistical approach in conjunction with the Locally Self-consistent Multiple-Scattering (LSMS) method to explore the magnetic states responsible for the magnet-caloric effect in this material. The effects of alloying agents on the transition temperatures of the Ni2MnGa alloy were investigated using differential scanning calorimetry (DSC) and superconducting quantum interference device (SQUID). Neutron scattering experiments were performed to observe the structural and magnetic phase transformations at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL) on alloys of Ni-Mn-Ga and Ni-Mn-Ga-Cu-Fe. Data from the observations are discussed in comparison with the computational studies.

  12. Magnetic Materials at finite Temperatures: thermodynamics and combined spin and molecular dynamics derived from first principles calculations

    SciTech Connect (OSTI)

    Eisenbach, Markus; Perera, Meewanage Dilina N; Landau, David P; Nicholson, Don M; Yin, Junqi; Brown, Greg

    2015-01-01

    We present a unified approach to describe the combined behavior of the atomic and magnetic degrees of freedom in magnetic materials. Using Monte Carlo simulations directly combined with first principles the Curie temperature can be obtained ab initio in good agreement with experimental values. The large scale constrained first principles calculations have been used to construct effective potentials for both the atomic and magnetic degrees of freedom that allow the unified study of influence of phonon-magnon coupling on the thermodynamics and dynamics of magnetic systems. The MC calculations predict the specific heat of iron in near perfect agreement with experimental results from 300K to above Tc and allow the identification of the importance of the magnon-phonon interaction at the phase-transition. Further Molecular Dynamics and Spin Dynamics calculations elucidate the dynamics of this coupling and open the potential for quantitative and predictive descriptions of dynamic structure factors in magnetic materials using first principles derived simulations.

  13. Super energy saver heat pump with dynamic hybrid phase change material

    DOE Patents [OSTI]

    Ally, Moonis Raza [Oak Ridge, TN; Tomlinson, John Jager [Knoxville, TN; Rice, Clifford Keith [Clinton, TN

    2010-07-20

    A heat pump has a refrigerant loop, a compressor in fluid communication with the refrigerant loop, at least one indoor heat exchanger in fluid communication with the refrigerant loop, and at least one outdoor heat exchanger in fluid communication with the refrigerant loop. The at least one outdoor heat exchanger has a phase change material in thermal communication with the refrigerant loop and in fluid communication with an outdoor environment. Other systems, devices, and methods are described.

  14. Maximizing NGL recovery by refrigeration optimization

    SciTech Connect (OSTI)

    Baldonedo H., A.H.

    1999-07-01

    PDVSA--Petroleo y Gas, S.A. has within its facilities in Lake Maracaibo two plants that extract liquids from natural gas (NGL), They use a combined mechanic refrigeration absorption with natural gasoline. Each of these plants processes 420 MMsccfd with a pressure of 535 psig and 95 F that comes from the compression plants PCTJ-2 and PCTJ-3 respectively. About 40 MMscfd of additional rich gas comes from the high pressure system. Under the present conditions these plants produce in the order of 16,800 and 23,800 b/d of NGL respectively, with a propane recovery percentage of approximately 75%, limited by the capacity of the refrigeration system. To optimize the operation and the design of the refrigeration system and to maximize the NGL recovery, a conceptual study was developed in which the following aspects about the process were evaluated: capacity of the refrigeration system, refrigeration requirements, identification of limitations and evaluation of the system improvements. Based on the results obtained it was concluded that by relocating some condensers, refurbishing the main refrigeration system turbines and using HIGH FLUX piping in the auxiliary refrigeration system of the evaporators, there will be an increase of 85% on the propane recovery, with an additional production of 25,000 b/d of NGL and 15 MMscfd of ethane rich gas.

  15. DOE Publishes Supplemental Proposed Determination for Miscellaneous Residential Refrigeration Products

    Broader source: Energy.gov [DOE]

    The Department of Energy has published a supplemental proposed determination regarding miscellaneous residential refrigeration products.

  16. Bearing construction for refrigeration compresssor

    DOE Patents [OSTI]

    Middleton, Marc G.; Nelson, Richard T.

    1988-01-01

    A hermetic refrigeration compressor has a cylinder block and a crankshaft rotatable about a vertical axis to reciprocate a piston in a cylinder on the cylinder block. A separate bearing housing is secured to the central portion of the cylinder block and extends vertically along the crankshaft, where it carries a pair of roller bearings to journal the crankshaft. The crankshaft has a radially extending flange which is journaled by a thrust-type roller bearing above the bearing housing to absorb the vertical forces on the crankshaft so that all three of the roller bearings are between the crankshaft and the bearing housing to maintain and control the close tolerances required by such bearings.

  17. Dual-circuit, multiple-effect refrigeration system and method

    DOE Patents [OSTI]

    DeVault, Robert C.

    1995-01-01

    A dual circuit absorption refrigeration system comprising a high temperature single-effect refrigeration loop and a lower temperature double-effect refrigeration loop separate from one another and provided with a double-condenser coupling therebetween. The high temperature condenser of the single-effect refrigeration loop is double coupled to both of the generators in the double-effect refrigeration loop to improve internal heat recovery and a heat and mass transfer additive such as 2-ethyl-1-hexanol is used in the lower temperature double-effect refrigeration loop to improve the performance of the absorber in the double-effect refrigeration loop.

  18. Refrigerant charge management in a heat pump water heater

    DOE Patents [OSTI]

    Chen, Jie; Hampton, Justin W.

    2014-06-24

    Heat pumps that heat or cool a space and that also heat water, refrigerant management systems for such heat pumps, methods of managing refrigerant charge, and methods for heating and cooling a space and heating water. Various embodiments deliver refrigerant gas to a heat exchanger that is not needed for transferring heat, drive liquid refrigerant out of that heat exchanger, isolate that heat exchanger against additional refrigerant flowing into it, and operate the heat pump while the heat exchanger is isolated. The heat exchanger can be isolated by closing an electronic expansion valve, actuating a refrigerant management valve, or both. Refrigerant charge can be controlled or adjusted by controlling how much liquid refrigerant is driven from the heat exchanger, by letting refrigerant back into the heat exchanger, or both. Heat pumps can be operated in different modes of operation, and segments of refrigerant conduit can be interconnected with various components.

  19. Method and apparatus for passive refrigerant retrieval and storage

    SciTech Connect (OSTI)

    Squire, D.C.

    1991-12-17

    This patent describes a method of retrieving and storing refrigerant from a cooling system being serviced of the type having a compressor for circulating a compressible refrigerant in a closed, pressurized system between a condenser and an evaporator to provide a cooling effect. It comprises: connecting one end of a refrigerant collector tube contained within a housing to the cooling system at the condenser outlet; connecting the interior of the housing to the compressor inlet; operating the cooling system compressor to pressurize refrigerant in the cooling system and pump the refrigerant into the collector tube; and discharging refrigerant from the collector tube into the housing interior through a metering valve where the refrigerant pressure is reduced and evaporates and cools the refrigerant remaining in the tube and the evaporated refrigerant is drawn into the compressor inlet whereby the refrigerant becomes trapped within the housing.

  20. DOE Reaches Settlements with Three Commercial Refrigeration Equipment

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Manufacturers | Department of Energy Reaches Settlements with Three Commercial Refrigeration Equipment Manufacturers DOE Reaches Settlements with Three Commercial Refrigeration Equipment Manufacturers March 1, 2016 - 6:20pm Addthis DOE settled enforcement actions against Utility Refrigerator, True Manufacturing, and Victory Refrigeration for distributing commercial refrigeration equipment in the United States that do not meet applicable energy conservation standards. As a part of the

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

    SciTech Connect (OSTI)

    Green, Michael A.

    2007-08-27

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

  2. Loveland Water & Power- Refrigerator Recycling Program

    Broader source: Energy.gov [DOE]

    Loveland Water & Power is providing an incentive for customers to recycle older, working refrigerators. Interested customers can call the utility to arrange a time to pick up the old...

  3. REFRIGERATION ESPECIALLY FOR VERY LOW TEMPERATURES

    DOE Patents [OSTI]

    Kennedy, P.B.; Smith, H.R. Jr.

    1960-09-13

    A refrigeration system for producing very low temperatures is described. The system of the invention employs a binary mixture refrigerant in a closed constant volume, e.g., Freon and ethylene. Such mixture is compressed in the gaseous state and is then separated in a fractionating column element of the system. Thenceforth, the first liquid to separate is employed stagewise to cool and liq uefy successive portions of the refrigerant at successively lower temperatures by means of heat exchangers coupled between the successive stages. When shut down, all of the volumes of the system are interconnected and a portion of the refrigerant remains liquid at ambient temperatures so that no dangerous overpressures develop. The system is therefore rugged, simple and dependable in operation.

  4. Refrigeration system having standing wave compressor

    DOE Patents [OSTI]

    Lucas, Timothy S.

    1992-01-01

    A compression-evaporation refrigeration system, wherein gaseous compression of the refrigerant is provided by a standing wave compressor. The standing wave compressor is modified so as to provide a separate subcooling system for the refrigerant, so that efficiency losses due to flashing are reduced. Subcooling occurs when heat exchange is provided between the refrigerant and a heat pumping surface, which is exposed to the standing acoustic wave within the standing wave compressor. A variable capacity and variable discharge pressure for the standing wave compressor is provided. A control circuit simultaneously varies the capacity and discharge pressure in response to changing operating conditions, thereby maintaining the minimum discharge pressure needed for condensation to occur at any time. Thus, the power consumption of the standing wave compressor is reduced and system efficiency is improved.

  5. Defrost Temperature Termination in Supermarket Refrigeration Systems

    SciTech Connect (OSTI)

    Fricke, Brian A; Sharma, Vishaldeep

    2011-11-01

    The objective of this project was to determine the potential energy savings associated with implementing demand defrost strategies to defrost supermarket refrigerated display case evaporators, as compared to the widely accepted current practice of controlling display case defrost cycles with a preset timer. The defrost heater energy use of several representative display case types was evaluated. In addition, demand defrost strategies for refrigerated display cases as well as those used in residential refrigerator/freezers were evaluated. Furthermore, it is anticipated that future work will include identifying a preferred defrost strategy, with input from Retail Energy Alliance members. Based on this strategy, a demand defrost system will be designed which is suitable for supermarket refrigerated display cases. Limited field testing of the preferred defrost strategy will be performed in a supermarket environment.

  6. Refrigerator Manufacturers: Proposed Penalty (2013-CE-5341)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Refrigerator Manufacturers, LLC failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

  7. Cospolich Refrigerator: Proposed Penalty (2013-CE-5314)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Cospolich Refrigerator Co, Inc. failed to certify walk-in cooler or freezer components as compliant with the energy conservation standards.

  8. Advances in refrigeration and heat transfer engineering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bansal, Pradeep; Cremaschi, Prof. Lorenzo

    2015-05-13

    This special edition of Science and Technology for the Built Environment (STBE) presents selected high quality papers that were presented at the 15th International Refrigeration and Air Conditioning Conference held at Purdue University during July 14-17 2014. All papers went through the additional review before being finally accepted for publication in this special issue of Science and Technology and the Built Environment. Altogether 20 papers made to this special issue that cover a wide range of topics, including advancements in alternative refrigerants, heat exchangers/heat transfer, nano-fluids, systems design and optimization and modeling approaches. Although CO2 may perhaps have been themore » most researched and popular refrigerant in the past decade, R32 is being seriously considered lately as an alternative and environmentally friendly refrigerant for small systems due to its low Global Warming Potential (GWP).« less

  9. DOE Closes Investigation of Whirlpool's Maytag Refrigerator

    Broader source: Energy.gov [DOE]

    The Department of Energy has closed its investigation into the energy efficiency of Whirlpool's Maytag refrigerator-freezer model "MSD2578VE." The Department opened this investigation and requested...

  10. DOE Closes Investigation of Arcelik's Blomberg Refrigerator

    Broader source: Energy.gov [DOE]

    The Department of Energy has closed its investigation into the energy efficiency of Arcelik's Blomberg refrigerator-freezer model # BRFB1450. The Department opened this investigation based on a...

  11. International Refrigeration: Proposed Penalty (2012-CE-1510)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that International Refrigeration Products failed to certify a various room air conditioners as compliant with the applicable energy conservation standards.

  12. Advances in refrigeration and heat transfer engineering

    SciTech Connect (OSTI)

    Bansal, Pradeep; Cremaschi, Prof. Lorenzo

    2015-05-13

    This special edition of Science and Technology for the Built Environment (STBE) presents selected high quality papers that were presented at the 15th International Refrigeration and Air Conditioning Conference held at Purdue University during July 14-17 2014. All papers went through the additional review before being finally accepted for publication in this special issue of Science and Technology and the Built Environment. Altogether 20 papers made to this special issue that cover a wide range of topics, including advancements in alternative refrigerants, heat exchangers/heat transfer, nano-fluids, systems design and optimization and modeling approaches. Although CO2 may perhaps have been the most researched and popular refrigerant in the past decade, R32 is being seriously considered lately as an alternative and environmentally friendly refrigerant for small systems due to its low Global Warming Potential (GWP).

  13. Combined cold compressor/ejector helium refrigerator

    DOE Patents [OSTI]

    Brown, Donald P.

    1985-01-01

    A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

  14. Combined cold compressor/ejector helium refrigerator

    DOE Patents [OSTI]

    Brown, D.P.

    1984-06-05

    A refrigeration apparatus having an ejector operatively connected with a cold compressor to form a two-stage pumping system. This pumping system is used to lower the pressure, and thereby the temperature of a bath of boiling refrigerant (helium). The apparatus as thus arranged and operated has substantially improved operating efficiency when compared to other processes or arrangements for achieving a similar low pressure.

  15. Magnetic Processing A Pervasive Energy Efficient Technology for Next Generation Materials for Aerospace and Specialty Steel Markets

    SciTech Connect (OSTI)

    Mackiewicz-Ludtka, G.; Ludtka, G.M.; Ray, P.; Magee, J.

    2010-09-10

    Thermomagnetic Magnetic Processing is an exceptionally fertile, pervasive and cross-cutting technology that is just now being recognized by several major industry leaders for its significant potential to increase energy efficiency and materials performance for a myriad of energy intensive industries in a variety of areas and applications. ORNL has pioneered the use and development of large magnetic fields in thermomagnetically processing (T-MP) materials for altering materials phase equilibria and transformation kinetics. ORNL has discovered that using magnetic fields, we can produce unique materials responses. T-MP can produce unique phase stabilities & microstructures with improved materials performance for structural and functional applications not achieved with traditional processing techniques. These results suggest that there are unprecedented opportunities to produce significantly enhanced materials properties via atomistic level (nano-) microstructural control and manipulation. ORNL (in addition to others) have shown that grain boundary chemistry and precipitation kinetics are also affected by large magnetic fields. This CRADA has taken advantage of ORNLs unique, custom-designed thermo-magnetic, 9 Tesla superconducting magnet facility that enables rapid heating and cooling of metallic components within the magnet bore; as well as ORNLs expertise in high magnetic field (HMF) research. Carpenter Technologies, Corp., is a a US-based industrial company, that provides enhanced performance alloys for the Aerospace and Specialty Steel products. In this CRADA, Carpenter Technologies, Corp., is focusing on applying ORNLs Thermomagnetic Magnetic Processing (TMP) technology to improve their current and future proprietary materials product performance and open up new markets for their Aerospace and Specialty Steel products. Unprecedented mechanical property performance improvements have been demonstrated for a high strength bainitic alloy industrial/commercial alloy that is envisioned to provide the potential for new markets for this alloy. These thermomechanical processing results provide these alloys with a major breakthrough demonstrating that simultaneous improvements in yield strength and ductility are achieved: 12 %, 10%, 13%, and 22% increases in yield strength, elongation, reduction-in-area, and impact energy respectively. In addition, TMP appears to overcome detrimental chemical homogeneity impacts on uniform microstructure evolution.

  16. Energy Efficient Operation of Ammonia Refrigeration Systems

    SciTech Connect (OSTI)

    Mohammed, Abdul Qayyum; Wenning, Thomas J; Sever, Franc; Kissock, Professor Kelly

    2013-01-01

    Ammonia refrigeration systems typically offer many energy efficiency opportunities because of their size and complexity. This paper develops a model for simulating single-stage ammonia refrigeration systems, describes common energy saving opportunities, and uses the model to quantify those opportunities. The simulation model uses data that are typically available during site visits to ammonia refrigeration plants and can be calibrated to actual consumption and performance data if available. Annual electricity consumption for a base-case ammonia refrigeration system is simulated. The model is then used to quantify energy savings for six specific energy efficiency opportunities; reduce refrigeration load, increase suction pressure, employ dual suction, decrease minimum head pressure set-point, increase evaporative condenser capacity, and reclaim heat. Methods and considerations for achieving each saving opportunity are discussed. The model captures synergistic effects that result when more than one component or parameter is changed. This methodology represents an effective method to model and quantify common energy saving opportunities in ammonia refrigeration systems. The results indicate the range of savings that might be expected from common energy efficiency opportunities.

  17. Global warming impacts of ozone-safe refrigerants and refrigeration, heating, and air-conditioning technologies

    SciTech Connect (OSTI)

    Fischer, S.; Sand, J.; Baxter, V.

    1997-12-01

    International agreements mandate the phase-out of many chlorine containing compounds that are used as the working fluid in refrigeration, air-conditioning, and heating equipment. Many of the chemical compounds that have been proposed, and are being used in place of the class of refrigerants eliminated by the Montreal Protocol are now being questioned because of their possible contributions to global warming. Natural refrigerants are put forth as inherently superior to manufactured refrigerants because they have very low or zero global warming potentials (GWPs). Questions are being raised about whether or not these manufactured refrigerants, primarily hydrofluorocarbons (HFCs), should be regulated and perhaps phased out in much the same manner as CFCs and HCFCs. Several of the major applications of refrigerants are examined in this paper and the results of an analysis of their contributions to greenhouse warming are presented. Supermarket refrigeration is shown to be an application where alternative technologies have the potential to reduce emissions of greenhouse gases (GHG) significantly with no clear advantage to either natural or HFC refrigerants. Mixed results are presented for automobile air conditioners with opportunities to reduce GHG emissions dependent on climate and comfort criteria. GHG emissions for hermetic and factory built systems (i.e. household refrigerators/freezers, unitary equipment, chillers) are shown to be dominated by energy use with much greater potential for reduction through efficiency improvements than by selection of refrigerant. The results for refrigerators also illustrate that hydrocarbon and carbon dioxide blown foam insulation have lower overall effects on GHG emissions than HFC blown foams at the cost of increased energy use.

  18. Rare-Earth-Free Permanent Magnets for Electrical Vehicle Motors and Wind Turbine Generators: Hexagonal Symmetry Based Materials Systems Mn-Bi and M-type Hexaferrite

    SciTech Connect (OSTI)

    Hong, Yang-Ki; Haskew, Timothy; Myryasov, Oleg; Jin, Sungho; Berkowitz, Ami

    2014-06-05

    The research we conducted focuses on the rare-earth (RE)-free permanent magnet by modeling, simulating, and synthesizing exchange coupled two-phase (hard/soft) RE-free core-shell nano-structured magnet. The RE-free magnets are made of magnetically hard core materials (high anisotropy materials including Mn-Bi-X and M-type hexaferrite) coated by soft shell materials (high magnetization materials including Fe-Co or Co). Therefore, our research helps understand the exchange coupling conditions of the core/shell magnets, interface exchange behavior between core and shell materials, formation mechanism of core/shell structures, stability conditions of core and shell materials, etc.

  19. Suboxide/subnitride formation on Ta masks during magnetic material etching by reactive plasmas

    SciTech Connect (OSTI)

    Li, Hu; Muraki, Yu; Karahashi, Kazuhiro; Hamaguchi, Satoshi

    2015-07-15

    Etching characteristics of tantalum (Ta) masks used in magnetoresistive random-access memory etching processes by carbon monoxide and ammonium (CO/NH{sub 3}) or methanol (CH{sub 3}OH) plasmas have been examined by mass-selected ion beam experiments with in-situ surface analyses. It has been suggested in earlier studies that etching of magnetic materials, i.e., Fe, Ni, Co, and their alloys, by such plasmas is mostly due to physical sputtering and etch selectivity of the process arises from etch resistance (i.e., low-sputtering yield) of the hard mask materials such as Ta. In this study, it is shown that, during Ta etching by energetic CO{sup +} or N{sup +} ions, suboxides or subnitrides are formed on the Ta surface, which reduces the apparent sputtering yield of Ta. It is also shown that the sputtering yield of Ta by energetic CO{sup +} or N{sup +} ions has a strong dependence on the angle of ion incidence, which suggests a correlation between the sputtering yield and the oxidation states of Ta in the suboxide or subnitride; the higher the oxidation state of Ta, the lower is the sputtering yield. These data account for the observed etch selectivity by CO/NH{sub 3} and CH{sub 3}OH plasmas.

  20. Refrigerated Warehouse Demand Response Strategy Guide

    SciTech Connect (OSTI)

    Scott, Doug; Castillo, Rafael; Larson, Kyle; Dobbs, Brian; Olsen, Daniel

    2015-11-01

    This guide summarizes demand response measures that can be implemented in refrigerated warehouses. In an appendix, it also addresses related energy efficiency opportunities. Reducing overall grid demand during peak periods and energy consumption has benefits for facility operators, grid operators, utility companies, and society. State wide demand response potential for the refrigerated warehouse sector in California is estimated to be over 22.1 Megawatts. Two categories of demand response strategies are described in this guide: load shifting and load shedding. Load shifting can be accomplished via pre-cooling, capacity limiting, and battery charger load management. Load shedding can be achieved by lighting reduction, demand defrost and defrost termination, infiltration reduction, and shutting down miscellaneous equipment. Estimation of the costs and benefits of demand response participation yields simple payback periods of 2-4 years. To improve demand response performance, it’s suggested to install air curtains and another form of infiltration barrier, such as a rollup door, for the passageways. Further modifications to increase efficiency of the refrigeration unit are also analyzed. A larger condenser can maintain the minimum saturated condensing temperature (SCT) for more hours of the day. Lowering the SCT reduces the compressor lift, which results in an overall increase in refrigeration system capacity and energy efficiency. Another way of saving energy in refrigerated warehouses is eliminating the use of under-floor resistance heaters. A more energy efficient alternative to resistance heaters is to utilize the heat that is being rejected from the condenser through a heat exchanger. These energy efficiency measures improve efficiency either by reducing the required electric energy input for the refrigeration system, by helping to curtail the refrigeration load on the system, or by reducing both the load and required energy input.

  1. Magnetic Systems Mimic Granular Materials | U.S. DOE Office of...

    Office of Science (SC) Website

    ... magnetic x-ray photon correlation spectroscopy" that uses coherent x-ray beams (similar to laser light) whose energy is tuned to resonantly interact with atomic magnetic moments. ...

  2. Anomalous magnetic behavior in nanocomposite materials of reduced graphene oxide-Ni/NiFe{sub 2}O{sub 4}

    SciTech Connect (OSTI)

    Kollu, Pratap E-mail: anirmalagrace@vit.ac.in; Prathapani, Sateesh; Varaprasadarao, Eswara K.; Mallick, Sudhanshu; Bahadur, D. E-mail: anirmalagrace@vit.ac.in; Santosh, Chella; Grace, Andrews Nirmala E-mail: anirmalagrace@vit.ac.in

    2014-08-04

    Magnetic Reduced Graphene Oxide-Nickel/NiFe{sub 2}O{sub 4} (RGO-Ni/NF) nanocomposite has been synthesized by one pot solvothermal method. Respective phase formations and their purities in the composite are confirmed by High Resolution Transmission Electron Microscope and X Ray Diffraction, respectively. For the RGO-Ni/NF composite material finite-size effects lead to the anomalous magnetic behavior, which is corroborated in temperature and field dependent magnetization curves. Here, we are reporting the behavior of higher magnetization values for Zero Field Cooled condition to that of Field Cooled for the RGO-Ni/NF nanocomposite. Also, the observed negative and positive moments in Hysteresis loops at relatively smaller applied fields (100?Oe and 200?Oe) are explained on the basis of surface spin disorder.

  3. Dynamic high pressure process for fabricating superconducting and permanent magnetic materials

    DOE Patents [OSTI]

    Nellis, William J.; Maple, M. Brian; Geballe, Theodore H.

    1988-01-01

    Shock wave formation of superconductive ceramic oxide electric and magnetic circuit elements with improved microstructures and mechanical properties.

  4. Dynamic high pressure process for fabricating superconducting and permanent magnetic materials

    DOE Patents [OSTI]

    Nellis, W.J.; Maple, M.B.; Geballe, T.H.

    1987-10-23

    Shock wave formation of superconductive ceramic oxide electric and magnetic circuit elements with improved microstructures and mechanical properties. 10 figs.

  5. Thermal and high magnetic field treatment of materials and associated apparatus

    DOE Patents [OSTI]

    Kisner, Roger A.; Wilgen, John B.; Ludtka, Gerard M.; Jaramillo, Roger A.; Mackiewicz-Ludtka, Gail

    2010-06-29

    An apparatus and method for altering characteristics, such as can include structural, magnetic, electrical, optical or acoustical characteristics, of an electrically-conductive workpiece utilizes a magnetic field within which the workpiece is positionable and schemes for thermally treating the workpiece by heating or cooling techniques in conjunction with the generated magnetic field so that the characteristics of the workpiece are effected by both the generated magnetic field and the thermal treatment of the workpiece.

  6. Thermal and high magnetic field treatment of materials and associated apparatus

    DOE Patents [OSTI]

    Kisner, Roger A.; Wilgen, John B.; Ludtka, Gerard M.; Jaramillo, Roger A.; Mackiewicz-Ludtka, Gail

    2007-01-09

    An apparatus and method for altering characteristics, such as can include structural, magnetic, electrical, optical or acoustical characteristics, of an electrically-conductive workpiece utilizes a magnetic field within which the workpiece is positionable and schemes for thermally treating the workpiece by heating or cooling techniques in conjunction with the generated magnetic field so that the characteristics of the workpiece are effected by both the generated magnetic field and the thermal treatment of the workpiece.

  7. ARTI Refrigerant Database. [Quarterly progress report, 1 July 1993--30 September 1993

    SciTech Connect (OSTI)

    Calm, J.M.

    1993-11-28

    The Refrigerant Database consolidates and facilitates access to information to assist industry in developing equipment using alternative refrigerants. The underlying purpose is to accelerate phase out of chemical compounds of environmental concern. The database provides bibliographic citations and abstracts for publications that may be useful in research and design of air-conditioning and refrigeration equipment. The complete documents are not included, though some may be added at a later date. The database identifies sources of specific information on R-32, R-123, R-124, R-125, R-134, R134a, R-141b, R-142b, R-143a, R-152a, R-227ea, R-245ca, R-290 (propane), R-717 (ammonia), ethers, and others as well as azeotropic and zeotropic blends of these fluids. It addresses lubricants including alkylbenzene, polyalkylene glycol, polyol ester, and other synthetics as well as mineral oils. It also references documents addressing compatibility of refrigerants and lubricants with metals, plastics, elastomers, motor insulation, and other materials used in refrigerant circuits. Incomplete citations or abstracts are provided for some documents. They are included to accelerate availability of the information and will be completed or replaced in future updates.

  8. DOE Reaches Settlements with Three Commercial Refrigeration Equipment...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    True agreed to a 36,400 civil penalty after manufacturing and distributing 182 units of commercial refrigerator models TCGG-72 and TCGG-72S. Utility Refrigerator agreed to ...

  9. Could You Save Money on Your Refrigerator? | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Could You Save Money on Your Refrigerator? Could You Save Money on Your Refrigerator? July 20, 2012 - 4:35pm Addthis Earlier this week, Amanda wrote about how you can save energy...

  10. Working Fluids Low Global Warming Potential Refrigerants - 2013...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    rack and system diagram for the CO2 refrigeration system.
    Credit: Oak Ridge National Lab High-Efficiency, Low-Emission Refrigeration System Workshop 2: Advanced HVAC&R ...

  11. DOE Resolves Avanti Refrigerator and Freezer Civil Penalty Case

    Broader source: Energy.gov [DOE]

    Today, the Department of Energy announced that it has resolved the civil penalty action against Mackle Company for its failure to certify that refrigerators and refrigerator-freezers sold under the...

  12. Proposed Methodology for LEED Baseline Refrigeration Modeling (Presentation)

    SciTech Connect (OSTI)

    Deru, M.

    2011-02-01

    This PowerPoint presentation summarizes a proposed methodology for LEED baseline refrigeration modeling. The presentation discusses why refrigeration modeling is important, the inputs of energy models, resources, reference building model cases, baseline model highlights, example savings calculations and results.

  13. Refrigerant pressurization system with a two-phase condensing ejector

    DOE Patents [OSTI]

    Bergander, Mark

    2009-07-14

    A refrigerant pressurization system including an ejector having a first conduit for flowing a liquid refrigerant therethrough and a nozzle for accelerating a vapor refrigerant therethrough. The first conduit is positioned such that the liquid refrigerant is discharged from the first conduit into the nozzle. The ejector includes a mixing chamber for condensing the vapor refrigerant. The mixing chamber comprises at least a portion of the nozzle and transitions into a second conduit having a substantially constant cross sectional area. The condensation of the vapor refrigerant in the mixing chamber causes the refrigerant mixture in at least a portion of the mixing chamber to be at a pressure greater than that of the refrigerant entering the nozzle and greater than that entering the first conduit.

  14. Disorder-Induced Microscopic Magnetic Memory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Magnets are not just for refrigerator doors-they are of paramount importance in today's digital information age. In the face of a rapidly growing appetite for data storage,...

  15. Induced magnetic anisotropy in Si-free nanocrystalline soft magnetic materials: A transmission x-ray diffraction study

    SciTech Connect (OSTI)

    Parsons, R. Suzuki, K.; Yanai, T.; Kishimoto, H.; Kato, A.; Ohnuma, M.

    2015-05-07

    In order to better understand the origin of field-induced anisotropy (K{sub u}) in Si-free nanocrystalline soft magnetic alloys, the lattice spacing of the bcc-Fe phase in nanocrystalline Fe{sub 94?x}Nb{sub 6}B{sub x} (x?=?10, 12, 14) alloys annealed under an applied magnetic field has been investigated by X-ray diffraction in transmission geometry (t-XRD) with the diffraction vector parallel and perpendicular to the field direction. The saturation magnetostriction (?{sub s}) of nanocrystalline Fe{sub 94?x}Nb{sub 6}B{sub x} was found to increase linearly with the volume fraction of the residual amorphous phase and is well described by taking into account the volume-weighted average of two local ?{sub s} values for the bcc-Fe nanocrystallites (?5??2?ppm) and the residual amorphous matrix (+8??2?ppm). The lattice distortion required to produce the measured K{sub u} values (?100?J/m{sup 3}) was estimated via the inverse magnetostrictive effect using the measured ?{sub s} values and was compared to the lattice spacing estimations made by t-XRD. The lattice strain required to produce K{sub u} under the magnetoelastic model was not observed by the t-XRD experiments and so the findings of this study suggest that the origin of magnetic field induced K{sub u} cannot be explained through the magnetoelastic effect.

  16. Toxicity Data to Determine Refrigerant Concentration Limits

    SciTech Connect (OSTI)

    Calm, James M.

    2000-09-30

    This report reviews toxicity data, identifies sources for them, and presents resulting exposure limits for refrigerants for consideration by qualified parties in developing safety guides, standards, codes, and regulations. It outlines a method to calculate an acute toxicity exposure limit (ATEL) and from it a recommended refrigerant concentration limit (RCL) for emergency exposures. The report focuses on acute toxicity with particular attention to lethality, cardiac sensitization, anesthetic and central nervous system effects, and other escape-impairing effects. It addresses R-11, R-12, R-22, R-23, R-113, R-114, R-116, R-123, R-124, R-125, R-134, R-134a, R-E134, R-141b, R-142b, R-143a, R-152a, R-218, R-227ea, R-236fa, R-245ca, R-245fa, R-290, R-500, R-502, R-600a, R-717, and R-744. It summarizes additional data for R-14, R-115, R-170 (ethane), R-C318, R-600 (n-butane), and R-1270 (propylene) to enable calculation of limits for blends incorporating them. The report summarizes the data a nd related safety information, including classifications and flammability data. It also presents a series of tables with proposed ATEL and RCL concentrations-in dimensionless form and the latter also in both metric (SI) and inch-pound (IP) units of measure-for both the cited refrigerants and 66 zerotropic and azeotropic blends. They include common refrigerants, such as R-404A, R-407C, R-410A, and R-507A, as well as others in commercial or developmental status. Appendices provide profiles for the cited single-compound refrigerants and for R-500 and R-502 as well as narrative toxicity summaries for common refrigerants. The report includes an extensive set of references.

  17. Working Fluids Low Global Warming Potential Refrigerants - 2013 Peer Review

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy Working Fluids Low Global Warming Potential Refrigerants - 2013 Peer Review Working Fluids Low Global Warming Potential Refrigerants - 2013 Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review PDF icon emrgtech12_vineyard_040313.pdf More Documents & Publications Brian Fricke conducts research in ORNL's Building Technologies Research & Integration Center. Low-GWP Refrigerants for Refrigeration Systems Image of

  18. DOE Collects Civil Penalties for Failure to Certify Consumer Refrigeration

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Products | Department of Energy Consumer Refrigeration Products DOE Collects Civil Penalties for Failure to Certify Consumer Refrigeration Products April 22, 2015 - 8:41pm Addthis The Office of Enforcement recently resolved enforcement actions against seven companies that failed to submit required reports to certify that their refrigerators, refrigerator-freezers, and/or freezers comply with federal energy conservation standards. DOE assessed civil penalties of $8,000 per manufacturer for

  19. DOE Proposes Higher Efficiency Standards for Refrigerators | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Higher Efficiency Standards for Refrigerators DOE Proposes Higher Efficiency Standards for Refrigerators September 28, 2010 - 12:00am Addthis WASHINGTON, DC - U.S. Energy Secretary Steven Chu today announced the release of a new proposed energy efficiency standard for residential refrigerators, refrigerator-freezers, and freezers. The standard, as proposed, could save consumers as much as $18.6 billion over thirty years. The Obama Administration has made efficiency standards a major

  20. EERE Success Story-New Refrigerant Boosts Energy Efficiency of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Supermarket Display Cases | Department of Energy Refrigerant Boosts Energy Efficiency of Supermarket Display Cases EERE Success Story-New Refrigerant Boosts Energy Efficiency of Supermarket Display Cases February 20, 2015 - 4:55pm Addthis EERE Success Story—New Refrigerant Boosts Energy Efficiency of Supermarket Display Cases Research supported by the Energy Department's Building Technologies Office has led to a major breakthrough in refrigeration systems' efficiency, and the result may

  1. New Refrigeration Technology Could Substantially Cut Energy Use |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy New Refrigeration Technology Could Substantially Cut Energy Use New Refrigeration Technology Could Substantially Cut Energy Use April 1, 2016 - 11:40pm Addthis New Energy Department-supported technologies under development at Ames National Laboratory could make refrigerators a substantially more energy efficient appliance. New Energy Department-supported technologies under development at Ames National Laboratory could make refrigerators a substantially more energy

  2. Everest Refrigeration: Order (2015-SE-42001) | Department of Energy

    Energy Savers [EERE]

    Order (2015-SE-42001) Everest Refrigeration: Order (2015-SE-42001) June 9, 2015 DOE ordered Bu Sung America Corporation (dba Everest Refrigeration) to pay a $12,080 civil penalty after finding Bu Sung had manufactured and distributed in commerce in the U.S. at least 64 units of noncompliant commercial refrigerator basic model ESGR3. The Order adopted a Compromise Agreement, which reflected settlement terms between DOE and Bu Sung. PDF icon Everest Refrigeration: Order (2015-SE-42001) More

  3. High-Performance Refrigerator Using Novel Rotating Heat Exchanger |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy High-Performance Refrigerator Using Novel Rotating Heat Exchanger High-Performance Refrigerator Using Novel Rotating Heat Exchanger Rotating heat exchangers installed in appliances and heat pumps have the potentially to reduce energy costs and refrigerant charge in a compact space. Rotating heat exchangers installed in appliances and heat pumps have the potentially to reduce energy costs and refrigerant charge in a compact space. Sandia-developed rotating heat exchanger

  4. Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications Credit: National Institute of Standards Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants Research & Development Roadmap: ...

  5. Helium refrigeration considerations for cryomodule design

    SciTech Connect (OSTI)

    Ganni, V.; Knudsen, P.

    2014-01-29

    Many of the present day accelerators are based on superconducting radio frequency (SRF) cavities, packaged in cryo-modules (CM), which depend on helium refrigeration at sub-atmospheric pressures, nominally 2 K. These specialized helium refrigeration systems are quite cost intensive to produce and operate. Particularly as there is typically no work extraction below the 4.5-K supply, it is important that the exergy loss between this temperature level and the CM load temperature(s) be minimized by the process configuration choices. This paper will present, compare and discuss several possible helium distribution process arrangements to support the CM loads.

  6. Removal of radioactive materials and heavy metals from water using magnetic resin

    DOE Patents [OSTI]

    Kochen, R.L.; Navratil, J.D.

    1997-01-21

    Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.

  7. Removal of radioactive materials and heavy metals from water using magnetic resin

    DOE Patents [OSTI]

    Kochen, Robert L. (Boulder, CO); Navratil, James D. (Simi Valley, CA)

    1997-01-21

    Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

  8. Reducing the Carbon Footprint of Commercial Refrigeration Systems Using Life Cycle Climate Performance Analysis: From System Design to Refrigerant Options

    SciTech Connect (OSTI)

    Fricke, Brian A; Abdelaziz, Omar; Vineyard, Edward Allan

    2013-01-01

    In this paper, Life Cycle Climate Performance (LCCP) analysis is used to estimate lifetime direct and indirect carbon dioxide equivalent gas emissions of various refrigerant options and commercial refrigeration system designs, including the multiplex DX system with various hydrofluorocarbon (HFC) refrigerants, the HFC/R744 cascade system incorporating a medium-temperature R744 secondary loop, and the transcritical R744 booster system. The results of the LCCP analysis are presented, including the direct and indirect carbon dioxide equivalent emissions for each refrigeration system and refrigerant option. Based on the results of the LCCP analysis, recommendations are given for the selection of low GWP replacement refrigerants for use in existing commercial refrigeration systems, as well as for the selection of commercial refrigeration system designs with low carbon dioxide equivalent emissions, suitable for new installations.

  9. Literature survey of heat transfer enhancement techniques in refrigeration applications

    SciTech Connect (OSTI)

    Jensen, M.K.; Shome, B.

    1994-05-01

    A survey has been performed of the technical and patent literature on enhanced heat transfer of refrigerants in pool boiling, forced convection evaporation, and condensation. Extensive bibliographies of the technical literature and patents are given. Many passive and active techniques were examined for pure refrigerants, refrigerant-oil mixtures, and refrigerant mixtures. The citations were categorized according to enhancement technique, heat transfer mode, and tube or shell side focus. The effects of the enhancement techniques relative to smooth and/or pure refrigerants were illustrated through the discussion of selected papers. Patented enhancement techniques also are discussed. Enhanced heat transfer has demonstrated significant improvements in performance in many refrigerant applications. However, refrigerant mixtures and refrigerant-oil mixtures have not been studied extensively; no research has been performed with enhanced refrigerant mixtures with oil. Most studies have been of the parametric type; there has been inadequate examination of the fundamental processes governing enhanced refrigerant heat transfer, but some modeling is being done and correlations developed. It is clear that an enhancement technique must be optimized for the refrigerant and operating condition. Fundamental processes governing the heat transfer must be examined if models for enhancement techniques are to be developed; these models could provide the method to optimize a surface. Refrigerant mixtures, with and without oil present, must be studied with enhancement devices; there is too little known to be able to estimate the effects of mixtures (particularly NARMs) with enhanced heat transfer. Other conclusions and recommendations are offered.

  10. Method and apparatus for de-superheating refrigerant

    DOE Patents [OSTI]

    Zess, J.A.; Drost, M.K.; Call, C.J.

    1997-11-25

    The present invention is an apparatus and method for de-superheating a primary refrigerant leaving a compressor wherein a secondary refrigerant is used between the primary refrigerant to be de-superheated. Reject heat is advantageously used for heat reclaim. 7 figs.

  11. Retrofitting Doors on Open Refrigerated Cases | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Retrofitting Doors on Open Refrigerated Cases Retrofitting Doors on Open Refrigerated Cases Commercial Buildings Integration Project for the 2013 Building Technologies Office's Program Peer Review PDF icon commlbldgs18_goetzler_040413.pdf More Documents & Publications Better Buildings Alliance - 2013 BTO Peer Review Working Fluids Low Global Warming Potential Refrigerants - 2013 Peer Review Better Buildings Alliance Equipment Performance Specifications - 2013 BTO Peer

  12. Control method for mixed refrigerant based natural gas liquefier

    DOE Patents [OSTI]

    Kountz, Kenneth J.; Bishop, Patrick M.

    2003-01-01

    In a natural gas liquefaction system having a refrigerant storage circuit, a refrigerant circulation circuit in fluid communication with the refrigerant storage circuit, and a natural gas liquefaction circuit in thermal communication with the refrigerant circulation circuit, a method for liquefaction of natural gas in which pressure in the refrigerant circulation circuit is adjusted to below about 175 psig by exchange of refrigerant with the refrigerant storage circuit. A variable speed motor is started whereby operation of a compressor is initiated. The compressor is operated at full discharge capacity. Operation of an expansion valve is initiated whereby suction pressure at the suction pressure port of the compressor is maintained below about 30 psig and discharge pressure at the discharge pressure port of the compressor is maintained below about 350 psig. Refrigerant vapor is introduced from the refrigerant holding tank into the refrigerant circulation circuit until the suction pressure is reduced to below about 15 psig, after which flow of the refrigerant vapor from the refrigerant holding tank is terminated. Natural gas is then introduced into a natural gas liquefier, resulting in liquefaction of the natural gas.

  13. U.S. Rare Earth Magnet Patents Table | Critical Materials Institute

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    U.S. Rare Earth Magnet Patents Table Neodymium-iron-boron magnet created with one-step refining process developed at The Ames Laboratory. CMI reviewed the U.S. patent database to better understand what is known about rare earth magnets and to identify potential areas to explore. Based on this, CMI created a table of more than 460 recent U.S. patents that address rare earth magnet compositions and processes. The table is available as a searchable pdf document (updated March 1, 2016). Information

  14. The Prospects of Alternatives to Vapor Compression Technology for Space Cooling and Food Refrigeration Applications

    SciTech Connect (OSTI)

    Brown, Daryl R.; Dirks, James A.; Fernandez, Nicholas; Stout, Tyson E.

    2010-03-31

    Five alternatives to vapor compression technology were qualitatively evaluated to determine their prospects for being better than vapor compression for space cooling and food refrigeration applications. The results of the assessment are summarized in the report. Overall, thermoacoustic and magnetic technologies were judged to have the best prospects for competing with vapor compression technology, with thermotunneling, thermoelectric, and thermionic technologies trailing behind in that order.

  15. 2014-04-10 Issuance: Test Procedures for Refrigerators, Refrigerator-Freezers, and Freezers; Final Rule

    Broader source: Energy.gov [DOE]

    This document is a pre-publication Federal Register final rule regarding test procedures for residential refrigerators and freezers, as issued by the Deputy Assistant Secretary for Energy Efficiency on April 10, 2014.

  16. Floating Loop System For Cooling Integrated Motors And Inverters Using Hot Liquid Refrigerant

    DOE Patents [OSTI]

    Hsu, John S [Oak Ridge, TN; Ayers, Curtis W [Kingston, TN; Coomer, Chester [Knoxville, TN; Marlino, Laura D [Oak Ridge, TN

    2006-02-07

    A floating loop vehicle component cooling and air-conditioning system having at least one compressor for compressing cool vapor refrigerant into hot vapor refrigerant; at least one condenser for condensing the hot vapor refrigerant into hot liquid refrigerant by exchanging heat with outdoor air; at least one floating loop component cooling device for evaporating the hot liquid refrigerant into hot vapor refrigerant; at least one expansion device for expanding the hot liquid refrigerant into cool liquid refrigerant; at least one air conditioning evaporator for evaporating the cool liquid refrigerant into cool vapor refrigerant by exchanging heat with indoor air; and piping for interconnecting components of the cooling and air conditioning system.

  17. Measurements with a recuperative superfluid Stirling refrigerator

    SciTech Connect (OSTI)

    Watanabe, A.; Swift, G.W.; Brisson, J.G.

    1995-08-01

    A superfluid Stirling refrigerator cooled to 168 mK using a 4.9% {sup 3}He- {sup 4}He mixture and exhausting its waste heat at 383 mK. Cooling power versus temperature and speed is presented for 4.9%, 17%, and 36% mixtures. At the highest concentration, a dissipation mechanism of unknown origin is observed.

  18. Waste Heat Recapture from Supermarket Refrigeration Systems

    SciTech Connect (OSTI)

    Fricke, Brian A

    2011-11-01

    The objective of this project was to determine the potential energy savings associated with improved utilization of waste heat from supermarket refrigeration systems. Existing and advanced strategies for waste heat recovery in supermarkets were analyzed, including options from advanced sources such as combined heat and power (CHP), micro-turbines and fuel cells.

  19. Covered Product Category: Refrigerated Beverage Vending Machines

    Broader source: Energy.gov [DOE]

    FEMP provides acquisition guidance and Federal efficiency requirements across a variety of product categories, including refrigerated beverage vending machines, which are covered by the ENERGY STAR program. Federal laws and requirements mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law.

  20. Solubility modeling of refrigerant/lubricant mixtures

    SciTech Connect (OSTI)

    Michels, H.H.; Sienel, T.H.

    1996-12-31

    A general model for predicting the solubility properties of refrigerant/lubricant mixtures has been developed based on applicable theory for the excess Gibbs energy of non-ideal solutions. In our approach, flexible thermodynamic forms are chosen to describe the properties of both the gas and liquid phases of refrigerant/lubricant mixtures. After an extensive study of models for describing non-ideal liquid effects, the Wohl-suffix equations, which have been extensively utilized in the analysis of hydrocarbon mixtures, have been developed into a general form applicable to mixtures where one component is a POE lubricant. In the present study we have analyzed several POEs where structural and thermophysical property data were available. Data were also collected from several sources on the solubility of refrigerant/lubricant binary pairs. We have developed a computer code (NISC), based on the Wohl model, that predicts dew point or bubble point conditions over a wide range of composition and temperature. Our present analysis covers mixtures containing up to three refrigerant molecules and one lubricant. The present code can be used to analyze the properties of R-410a and R-407c in mixtures with a POE lubricant. Comparisons with other models, such as the Wilson or modified Wilson equations, indicate that the Wohl-suffix equations yield more reliable predictions for HFC/POE mixtures.

  1. Refrigeration in a world without CFCs

    SciTech Connect (OSTI)

    Garland, R.W.; Adcock, P.W.

    1996-09-01

    In an era of heightened awareness of energy efficiency and the associated environmental impacts, many industries, worldwide, are exploring ``environmentally friendly`` technologies that provide equivalent or improved performance while reducing or eliminating harmful side effects. The refrigeration and air conditioning industry, due to its reliance on CFCs and HCFCs has invested in research in alternatives to the industry standard vapor compression machines. One alternative technology with great promise is chemical absorption. Absorption chillers offer comparable refrigeration output with reduced SO{sub 2}, CO{sub 2}, and NO{sub x} emissions. Additionally, absorption chillers do not use CFCs or HCFCs, refrigerants that contribute to ozone depletion and global warming. The purpose of this paper is to provide an introduction for those new to absorption technology as well as a discussion of selected high efficiency cycles and environmental impacts for those familiar with absorption. The introduction will include a brief history of absorption and a description of the basic refrigeration cycle, while the advanced sections will discuss triple-effect technology and a life-cycle or ``systems`` approach to evaluating global warming impacts.

  2. Case Study: Transcritical Carbon Dioxide Supermarket Refrigeration Systems

    Broader source: Energy.gov [DOE]

    This case study documents one year of operating experience with a transcritical carbon dioxide (TC CO2) booster refrigeration system at Delhaize America’s Hannaford supermarket location in Turner, Maine. This supermarket, which began operation in June 2013, is the first supermarket installation in the U.S. of a TC CO2 booster refrigeration system. We compare refrigeration system performance to that for a supermarket having nearly identical layout and refrigeration loads, in a similar climate and of similar vintage, that uses a conventional hydrofluorocarbon (HFC) refrigerant. Delhaize provided the submetered and utility data used to generate the performance summaries herein.

  3. Final Report: MATERIALS, STRANDS, AND CABLES FOR SUPERCONDUCTING ACCELERATOR MAGNETS [Grant Number DE-SC0010312

    SciTech Connect (OSTI)

    Sumption, Mike; Collings, E.

    2014-10-29

    Our program consisted of the two components: Strand Research and Cable Research, with a focus on Nb3Sn, Bi2212, and YBCO for accelerator magnet applications. We demonstrated a method to refine the grains in Nb3Sn by a factor of two, reaching 45 nm grain sizes, and layer Jcs of 6 kA/mm2 at 12 T. W also measured conductor magnetization for field quality. This has been done both with Nb3Sn conductor, as well as Bi:2212 strand. Work in support of quench studies of YBCO coils was also performed. Cable loss studies in Nb3Sn focused on connecting and comparing persistent magnetization and coupling magnetization for considering their relative impact on HEP machines. In the area of HTS cables, we have investigated both the quench in multistrand YBCO CORC cables, as well as the magnetization of these cables for use in high field magnets. In addition, we examined the magnetic and thermal properties of large (50 T) solenoids.

  4. Dilution cycle control for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C.

    1984-01-01

    A dilution cycle control system for an absorption refrigeration system is disclosed. The control system includes a time delay relay for sensing shutdown of the absorption refrigeration system and for generating a control signal only after expiration of a preselected time period measured from the sensed shutdown of the absorption refrigeration system, during which the absorption refrigeration system is not restarted. A dilution cycle for the absorption refrigeration system is initiated in response to generation of a control signal by the time delay relay. This control system is particularly suitable for use with an absorption refrigeration system which is frequently cycled on and off since the time delay provided by the control system prevents needless dilution of the absorption refrigeration system when the system is turned off for only a short period of time and then is turned back on.

  5. Development of vehicle magnetic air conditioner (VMAC) technology. Final

    Office of Scientific and Technical Information (OSTI)

    report (Technical Report) | SciTech Connect Development of vehicle magnetic air conditioner (VMAC) technology. Final report Citation Details In-Document Search Title: Development of vehicle magnetic air conditioner (VMAC) technology. Final report The objective of Phase I was to explore the feasibility of the development of a new solid state refrigeration technology - magnetic refrigeration - in order to reduce power consumption of a vehicle air conditioner by 30%. The feasibility study was

  6. MAGNETS

    DOE Patents [OSTI]

    Hofacker, H.B.

    1958-09-23

    This patent relates to nmgnets used in a calutron and more particularly to means fur clamping an assembly of magnet coils and coil spacers into tightly assembled relation in a fluid-tight vessel. The magnet comprises windings made up of an assembly of alternate pan-cake type coils and spacers disposed in a fluid-tight vessel. At one end of the tank a plurality of clamping strips are held firmly against the assembly by adjustable bolts extending through the adjacent wall. The foregoing arrangement permits taking up any looseness which may develop in the assembly of coils and spacers.

  7. Method for preparing high cure temperature rare earth iron compound magnetic material

    DOE Patents [OSTI]

    Huang, Yuhong; Wei, Qiang; Zheng, Haixing

    2002-01-01

    Insertion of light elements such as H,C, or N in the R.sub.2 Fe.sub.17 (R=rare earth metal) series has been found to modify the magnetic properties of these compounds, which thus become prospective candidates for high performance permanent magnets. The most spectacular changes are increases of the Curie temperature, T.sub.c, of the magnetization, M.sub.s, and of coercivity, H.sub.c, upon interstitial insertion. A preliminary product having a component R--Fe--C,N phase is produced by a chemical route. Rare earth metal and iron amides are synthesized followed by pyrolysis and sintering in an inert or reduced atmosphere, as a result of which, the R--Fe--C,N phases are formed. Fabrication of sintered rare earth iron nitride and carbonitride bulk magnet is impossible via conventional process due to the limitation of nitridation method.

  8. IEA Annex 26: Advanced Supermarket Refrigeration/Heat Recovery Systems

    SciTech Connect (OSTI)

    Baxter, VAN

    2003-05-19

    With increased concern about the impact of refrigerant leakage on global warming, a number of new supermarket refrigeration system configurations requiring significantly less refrigerant charge are being considered. In order to help promote the development of advanced systems and expand the knowledge base for energy-efficient supermarket technology, the International Energy Agency (IEA) established IEA Annex 26 (Advanced Supermarket Refrigeration/Heat Recovery Systems) under the ''IEA Implementing Agreement on Heat Pumping Technologies''. Annex 26 focuses on demonstrating and documenting the energy saving and environmental benefits of advanced systems design for food refrigeration and space heating and cooling for supermarkets. Advanced in this context means systems that use less energy, require less refrigerant and produce lower refrigerant emissions. Stated another way, the goal is to identify supermarket refrigeration and HVAC technology options that reduce the total equivalent warming impact (TEWI) of supermarkets by reducing both system energy use (increasing efficiency) and reducing total refrigerant charge. The Annex has five participating countries: Canada, Denmark, Sweden, the United Kingdom, and the United States. The working program of the Annex has involved analytical and experimental investigation of several candidate system design approaches to determine their potential to reduce refrigerant usage and energy consumption. Advanced refrigeration system types investigated include the following: distributed compressor systems--small parallel compressor racks are located in close proximity to the food display cases they serve thus significantly shortening the connecting refrigerant line lengths; secondary loop systems--one or more central chillers are used to refrigerate a secondary coolant (e.g. brine, ice slurry, or CO2) that is pumped to the food display cases on the sales floor; self-contained display cases--each food display case has its own refrigeration unit; low-charge direct expansion--similar to conventional multiplex refrigeration systems but with improved controls to limit charge. Means to integrate store HVAC systems for space heating/cooling with the refrigeration system have been investigated as well. One approach is to use heat pumps to recover refrigeration waste heat and raise it to a sufficient level to provide for store heating needs. Another involves use of combined heating and power (CHP) or combined cooling, heating, and power (CCHP) systems to integrate the refrigeration, HVAC, and power services in stores. Other methods including direct recovery of refrigeration reject heat for space and water heating have also been examined.

  9. Magnetic Force Microscopy Study of Zr2Co11 -Based Nanocrystalline Materials: Effect of Mo Addition

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yue, Lanping; Jin, Yunlong; Zhang, Wenyong; Sellmyer, David J.

    2015-01-01

    Tmore » he addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. he effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox(x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. he coercivity of the samples increases with the increase in Mo content (x≤1.5). he maximum energy product(BH)maxincreases with increasingxfrom 0.5 MGOe forx=0to a maximum value of 4.2 MGOe forx=1.5. he smallest domain size with a relatively short magnetic correlation length of 128 nm and largest root-mean-square phase shiftΦrmsvalue of 0.66° are observed for thex=1.5. he optimal Mo addition promotes magnetic domain structure refinement and thus leads to a significant increase in coercivity and energy product in this sample.« less

  10. SCREW COMPRESSOR CHARACTERISTICS FOR HELIUM REFRIGERATION SYSTEMS

    SciTech Connect (OSTI)

    Ganni, Venkatarao; Knudsen, Peter; Creel, Jonathan; Arenius, Dana; Casagrande, Fabio; Howell, Matt

    2008-03-01

    The oil injected screw compressors have practically replaced all other types of compressors in modern helium refrigeration systems due to their large displacement capacity, minimal vibration, reliability and capability of handling helium's high heat of compression.At the present state of compressor system designs for helium systems, typically two-thirds of the lost input power is due to the compression system. Therefore it is important to understand the isothermal and volumetric efficiencies of these machines to help properly design these compression systems to match the refrigeration process. This presentation summarizes separate tests that have been conducted on Sullair compressors at the Superconducting Super-Collider Laboratory (SSCL) in 1993, Howden compressors at Jefferson Lab (JLab) in 2006 and Howden compressors at the Spallation Neutron Source (SNS) in 2006. This work is part of an ongoing study at JLab to understand the theoretical basis for these efficiencies and their loss

  11. Measurements of the efficiency and refrigeration power of pulse-tube refrigerators

    SciTech Connect (OSTI)

    Herrmann, S.; Radebaugh, R.

    1986-09-01

    Pulse-tube or thermoacoustic refrigerators have the potential for high reliability since they require only one moving part - an oscillating piston or diaphragm at room temperature. If a tube is closed at one end and connected to a pressure-wave generator at the open end, and if the phase angle between mass flow and pressure is shifted from 90/sup 0/, then refrigeration occurs at the open end. The shift in phase angle can be realized by thermal relaxation between the gas and the tube walls or by an orifice at the closed end. A low temperature of 60 K using helium gas in a one-stage orifice pulse tube has been achieved at NBS. The report describes the first measurements of the efficiency, refrigeration power, and refrigeration power per unit mass flow, for three pulse-tube refrigerators. Three tube sizes, differing in length and diameter, were studied over a frequency range of 3 to 11.5 Hz. Cooling efficiencies as high as 90% of the Carnot efficiency were obtained when compressor and regenerator losses are neglected.

  12. Tapered pulse tube for pulse tube refrigerators

    DOE Patents [OSTI]

    Swift, Gregory W.; Olson, Jeffrey R.

    1999-01-01

    Thermal insulation of the pulse tube in a pulse-tube refrigerator is maintained by optimally varying the radius of the pulse tube to suppress convective heat loss from mass flux streaming in the pulse tube. A simple cone with an optimum taper angle will often provide sufficient improvement. Alternatively, the pulse tube radius r as a function of axial position x can be shaped with r(x) such that streaming is optimally suppressed at each x.

  13. Extension of a Virtual Refrigerant Charge Sensor

    SciTech Connect (OSTI)

    Kim, Woohyun; Braun, J.

    2015-07-01

    The primary goal of the work described in this paper was to evaluate and extend a virtual refrigerant charge sensor (VRC) for determining refrigerant charge for equipment having variable-speed compressors and fans. To evaluate the accuracy of the VRC, data were first collected from previous laboratory tests for different systems and over a wide range of operating conditions. In addition, new laboratory tests were performed to consider conditions not available within the existing data set. The systems for the new laboratory tests were two residential ductless split heat pump systems that employ a variable-speed compressor and R-410a as the refrigerant. Based on the evaluations, the original virtual charge sensor (termed model I) was found to work well in estimating the refrigerant charge for systems with a variable-speed compressor under many operating conditions. However, for extreme test conditions such as low outdoor temperatures and low compressor speed, the VRC needed to be improved. To overcome the limitations, the model associated with the VRC sensor was modified to include a term involving the inlet quality to the evaporator estimated from the condenser outlet condition (termed model II). Both model I and II showed good performance in terms of predicting charge levels for systems with a constant speed compressor, but model II gave better performance for systems with a variable-speed compressor. However, when the superheat of the compressor was zero, neither model I nor II could accurately predict charge level. Therefore, a third approach (Model III) was developed that includes the discharge superheat of the compressor. This model improved performance for a laboratory-tested system that included a number of points with no superheat entering the compressor.

  14. Development of Low Global Warming Potential Refrigerant Solutions for Commercial Refrigeration Systems using a Life Cycle Climate Performance Design Tool

    SciTech Connect (OSTI)

    Abdelaziz, Omar; Fricke, Brian A; Vineyard, Edward Allan

    2012-01-01

    Commercial refrigeration systems are known to be prone to high leak rates and to consume large amounts of electricity. As such, direct emissions related to refrigerant leakage and indirect emissions resulting from primary energy consumption contribute greatly to their Life Cycle Climate Performance (LCCP). In this paper, an LCCP design tool is used to evaluate the performance of a typical commercial refrigeration system with alternative refrigerants and minor system modifications to provide lower Global Warming Potential (GWP) refrigerant solutions with improved LCCP compared to baseline systems. The LCCP design tool accounts for system performance, ambient temperature, and system load; system performance is evaluated using a validated vapor compression system simulation tool while ambient temperature and system load are devised from a widely used building energy modeling tool (EnergyPlus). The LCCP design tool also accounts for the change in hourly electricity emission rate to yield an accurate prediction of indirect emissions. The analysis shows that conventional commercial refrigeration system life cycle emissions are largely due to direct emissions associated with refrigerant leaks and that system efficiency plays a smaller role in the LCCP. However, as a transition occurs to low GWP refrigerants, the indirect emissions become more relevant. Low GWP refrigerants may not be suitable for drop-in replacements in conventional commercial refrigeration systems; however some mixtures may be introduced as transitional drop-in replacements. These transitional refrigerants have a significantly lower GWP than baseline refrigerants and as such, improved LCCP. The paper concludes with a brief discussion on the tradeoffs between refrigerant GWP, efficiency and capacity.

  15. CBEI: Virtual Refrigerant Charge Sensing and Load Metering - 2015 Peer

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Review | Department of Energy Virtual Refrigerant Charge Sensing and Load Metering - 2015 Peer Review CBEI: Virtual Refrigerant Charge Sensing and Load Metering - 2015 Peer Review Presenter: James Braun, Purdue University View the Presentation PDF icon CBEI: Virtual Refrigerant Charge Sensing and Load Metering - 2015 Peer Review More Documents & Publications CBEI: FDD for Advanced RTUs - 2015 Peer Review Control and Diagnostics for Rooftop Units - 2014 BTO Peer Review CBEI: Coordinating

  16. Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants -

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2013 Peer Review | Department of Energy Refrigerants - 2013 Peer Review Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants - 2013 Peer Review Emerging Technologies Project for the 2013 Building Technologies Office's Program Peer Review PDF icon emrgtech13_mclinden_040213.pdf More Documents & Publications Credit: National Institute of Standards Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants Research & Development Roadmap: Next-Generation Low

  17. EERE Success Story-New Advanced Refrigeration Technology Provides Clean

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy, Low Utility Bills for Supermarkets | Department of Energy Advanced Refrigeration Technology Provides Clean Energy, Low Utility Bills for Supermarkets EERE Success Story-New Advanced Refrigeration Technology Provides Clean Energy, Low Utility Bills for Supermarkets July 16, 2015 - 2:23pm Addthis Oak Ridge National Laboratory's (ORNL's) Brian Fricke tests Hillphoenix's Advansor Refrigeration System in ORNL's state-of-the-art Building Technologies Research & Integration Center

  18. Hydrophilic structures for condensation management in refrigerator appliances

    DOE Patents [OSTI]

    Kuehl, Steven John; Vonderhaar, John J; Wu, Guolian; Wu, Mianxue

    2014-10-21

    A refrigerator appliance that includes a freezer compartment having a freezer compartment door, and a refrigeration compartment having at least one refrigeration compartment door. The appliance further includes a mullion with an exterior surface. The mullion divides the compartments and the exterior surface directs condensation toward a transfer point. The appliance may also include a cabinet that houses the compartments and has two sides, each with an exterior surface. Further, at least one exterior surface directs condensation toward a transfer point.

  19. Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Burden RFI | Department of Energy Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI These comments are submitted by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) in response to the U.S. Department of Energy's (DOE) notice in the August 8, 2012 Federal Register requesting information to assist DOE in reviewing existing regulations and in making its

  20. Purchasing Energy-Efficient Commercial Refrigerators and Freezers |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Refrigerators and Freezers Purchasing Energy-Efficient Commercial Refrigerators and Freezers The Federal Energy Management Program (FEMP) provides acquisition guidance for commercial refrigerators and freezers, a product category covered by ENERGY STAR efficiency requirements. Federal laws and requirements mandate that agencies purchase ENERGY STAR-qualified products or FEMP-designated products in all product categories covered by these programs and in any acquisition

  1. Purchasing Energy-Efficient Refrigerated Beverage Vending Machines |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Refrigerated Beverage Vending Machines Purchasing Energy-Efficient Refrigerated Beverage Vending Machines The Federal Energy Management Program (FEMP) provides acquisition guidance for refrigerated beverage vending machines, a product category covered by ENERGY STAR efficiency requirements. Federal laws and requirements mandate that agencies purchase ENERGY STAR-qualified products or FEMP-designated products in all product categories covered by these programs and in any

  2. 2014-04-10 Issuance: Test Procedures for Commercial Refrigeration

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Equipment; Final Rule | Department of Energy 0 Issuance: Test Procedures for Commercial Refrigeration Equipment; Final Rule 2014-04-10 Issuance: Test Procedures for Commercial Refrigeration Equipment; Final Rule This document is a pre-publication Federal Register final rule regarding test procedures for commercial refrigeration equipment, as issued by the Deputy Assistant Secretary for Energy Efficiency on April 10, 2014. Though it is not intended or expected, should any discrepancy occur

  3. 2014-11-26 Issuance: Test Procedures for Miscellaneous Refrigeration

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Products; Notice of Proposed Rulemaking | Department of Energy 6 Issuance: Test Procedures for Miscellaneous Refrigeration Products; Notice of Proposed Rulemaking 2014-11-26 Issuance: Test Procedures for Miscellaneous Refrigeration Products; Notice of Proposed Rulemaking This document is a pre-publication Federal Register notice of proposed rulemaking regarding test procedures for miscellaneous refrigeration products, as issued by the Deputy Assistant Secretary for Energy Efficiency on

  4. 6 Energy Saving Tips for Commercial Refrigerators and Freezers | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy 6 Energy Saving Tips for Commercial Refrigerators and Freezers 6 Energy Saving Tips for Commercial Refrigerators and Freezers February 28, 2014 - 6:11pm Addthis Dale Linkous carries pizza out of the walk-in freezer in the kitchen at the National Renewable Energy Laboratory in Golden, Colorado. The Energy Department <a href="http://energy.gov/articles/new-energy-efficiency-standards-commercial-refrigeration-equipment-cut-businesses-energy">announced new energy

  5. Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Materials Access to Hopper Phase II (Cray XE6) If you are a current NERSC user, you are enabled to use Hopper Phase II. Use your SSH client to connect to Hopper II:...

  6. Refrigeration Playbook. Heat Reclaim; Optimizing Heat Rejection and Refrigeration Heat Reclaim for Supermarket Energy Conservation

    SciTech Connect (OSTI)

    Reis, Chuck; Nelson, Eric; Armer, James; Johnson, Tim; Hirsch, Adam; Doebber, Ian

    2015-03-01

    The purpose of this playbook and accompanying spreadsheets is to generalize the detailed CBP analysis and to put tools in the hands of experienced refrigeration designers to evaluate multiple applications of refrigeration waste heat reclaim across the United States. Supermarkets with large portfolios of similar buildings can use these tools to assess the impact of large-scale implementation of heat reclaim systems. In addition, the playbook provides best practices for implementing heat reclaim systems to achieve the best long-term performance possible. It includes guidance on operations and maintenance as well as measurement and verification.

  7. Economizer refrigeration cycle space heating and cooling system and process

    DOE Patents [OSTI]

    Jardine, Douglas M.

    1983-01-01

    This invention relates to heating and cooling systems and more particularly to an improved system utilizing a Stirling Cycle engine heat pump in a refrigeration cycle.

  8. Active Diesel Emission Control Technology for Transport Refrigeration...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Active Diesel Emission Control Technology for Transport Refrigeration Units This project discusses a CARB Level 2+ verified active regeneration technology for smal diesel engines ...

  9. BTO Partners are Revolutionizing Refrigerators and Clothes Dryers...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... Environmentally friendly supermarket refrigeration technologies, such as the first hydro-fluorocarbon (HFC)-free CO2 system with 25 percent energy savings and 75 percent fewer ...

  10. DOE Opens Three Investigations into Alleged Refrigerator Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    submit detailed information about the design, marketing and U.S. sales of its Blomberg brand refrigerator-freezer, model "BRFB1450." The Department also requested testing data...

  11. Acoustic recovery of lost power in pulse tube refrigerators

    SciTech Connect (OSTI)

    Swift, G.W.; Gardner, D.L.; Backhaus, S.

    1999-02-01

    In an efficient Stirling-cycle cryocooler, the cold piston or displacer recovers power from the gas. This power is dissipated into heat in the orifice of an orifice pulse tube refrigerator, decreasing system efficiency. Recovery of some of this power in a pulse tube refrigerator, without sacrificing the simplicity and reliability inherent in a system with no cold moving parts, is described in this paper. In one method of such power recovery, the hot ends of both the regenerator and the pulse tube are connected to the front of the piston driving the refrigerator. Experimental data is presented demonstrating this method using a thermoacoustic driver instead of a piston driver. Control of time-averaged mass flux through the refrigerator is crucial to this power recovery, lest the refrigerator{close_quote}s cooling power be overwhelmed by a room-temperature mass flux. Two methods are demonstrated for control of mass flux: a barrier method, and a hydrodynamic method based on turbulent irreversible flow. At {minus}55{degree}C, the refrigerator provided cooling with 9{percent} of the Carnot coefficient of performance. With straightforward improvements, similar refrigerators should achieve efficiencies greater than those of prior pulse tube refrigerators and prior standing-wave thermoacoustic refrigerators, while maintaining the advantages of no moving parts. {copyright} {ital 1999 Acoustical Society of America.}

  12. EERE Success Story-New Refrigerant Boosts Energy Efficiency of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    EERE Success StoryNew Refrigerant Boosts Energy Efficiency of Supermarket Display Cases Research supported by the Energy Department's Building Technologies Office has led to ...

  13. Retrofitting Doors on Open Refrigerated Cases | Department of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    - 2013 BTO Peer Review Better Buildings Alliance Equipment Performance Specifications - 2013 BTO Peer Review Working Fluids Low Global Warming Potential Refrigerants - 2013...

  14. Low-Cost Electrochemical Compressor Utilizing Green Refrigerants...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Electrochemical Compressor Utilizing Green Refrigerants for HVAC Applications Low-Cost ... 31, 2017 Funding Opportunity: Building Energy Efficiency Frontiers and Innovation ...

  15. Economizer refrigeration cycle space heating and cooling system and process

    DOE Patents [OSTI]

    Jardine, D.M.

    1983-03-22

    This invention relates to heating and cooling systems and more particularly to an improved system utilizing a Stirling Cycle engine heat pump in a refrigeration cycle. 18 figs.

  16. Alternative Refrigerant Evaluation for High-Ambient-Temperature...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners Alternative Refrigerant Evaluation for High-Ambient-Temperature ...

  17. Transportation Refrigeration Unit (TRU) Retrofit with HUSS Active...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    PDF icon deer08bruenke.pdf More Documents & Publications Verifying TRU Passive DPF Cold Ambient Performance Active Diesel Emission Control Technology for Transport Refrigeration ...

  18. Air-Conditioning, Heating, and Refrigeration Institute (AHRI...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Air-Conditioning, Heating, and Refrigeration Institute (AHRI) Regulatory Burden RFI ... PDF icon DOE Com Reg Burden RFI 9-7-12.pdf More Documents & Publications Regulatory Burden ...

  19. Test results on a supercharged compressor for commercial refrigeration

    SciTech Connect (OSTI)

    Andrews, J.W.; Butcher, T.A.; Wilhelm, W.G. )

    1989-01-01

    This paper reports on a project whose objective was to quantify the technical benefits of using refrigerant R-502 in a supercharged reciprocating compressor for commercial refrigeration applications. The supercharged compressor concept used a special heat exchanger that subcools the major portion of the liquid refrigerant leaving the condenser. This subcooling is achieved by flashing the remaining portion of the condensed liquid through an expansion valve, thereby cooling it, and using it to absorb heat from the rest of the refrigerant. This supercharged stream is then fed to the cylinders through ports in the cylinder walls that are uncovered when the piston reaches bottom dead center.

  20. Dual stage active magnetic regenerator and method

    DOE Patents [OSTI]

    Pecharsky, V.K.; Gschneidner, K.A. Jr.

    1999-03-30

    A dual stage active magnetic regenerator refrigerator as well as method using the Joule-Brayton thermodynamic cycle includes a high temperature stage refrigerant comprising DyAl{sub 2} or (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} where x is selected to be greater than 0 and less than about 0.3 in combination with a low temperature stage comprising (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} where x is selected to be greater than about 0.5 and less than 1 to provide significantly improved refrigeration efficiency in the liquefaction of gaseous hydrogen. 17 figs.

  1. Dual stage active magnetic regenerator and method

    DOE Patents [OSTI]

    Pecharsky, Vitalij K.; Gschneidner, Jr., Karl A.

    1999-03-30

    A dual stage active magnetic regenerator refrigerator as well as method using the Joule-Brayton thermodynamic cycle includes a high temperature stage refrigerant comprising DyAl.sub.2 or (Dy.sub.1-x Er.sub.x)Al.sub.2 where x is selected to be greater than 0 and less than about 0.3 in combination with a low temperature stage comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 where x is selected to be greater than about 0.5 and less than 1 to provide significantly improved refrigeration efficiency in the liquefaction of gaseous hydrogen.

  2. Active magnetic regenerator

    DOE Patents [OSTI]

    Barclay, J.A.; Steyert, W.A.

    1981-01-27

    An apparatus and method for refrigeration are disclosed which provides efficient refrigeration over temperature ranges in excess of 20/sup 0/C and which requires no maintenance and is, therefore, usable on an unmanned satellite. The apparatus comprises a superconducting magnet which may be solenoidal. A piston comprising a substance such as a rare earth substance which is maintained near its Curie temperature reciprocates through the bore of the solenoidal magnet. A magnetic drive rod is connected to the piston and appropriate heat sinks are connected thereto. The piston is driven by a suitable mechanical drive such as an electric motor and cam. In practicing the invention, the body of the piston is magnetized and demagnetized as it moves through the magnetic field of the solenoid to approximate any of the following cycles or a condition thereof as well as, potentially, other cycles: Brayton, Carnot, Ericsson, and Stirling. Advantages of the present invention include: that refrigeration can be accomplished over at least a 20/sup 0/C scale at superconducting temperatures as well as at more conventional temperatures; very high efficiency, high reliability, and small size. (LCL)

  3. Tiny magnets could work in sensors, information encoding

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    headline to go to original article at phys.org. "Each nano-island is similar to a refrigerator magnet, with a north and a south pole at its tips," said Los Alamos physicist...

  4. The New York Power Authority`s energy-efficient refrigerator program for the New York City Housing Authority -- 1997 savings evaluation

    SciTech Connect (OSTI)

    Pratt, R.G.; Miller, J.D.

    1998-09-01

    This document describes the estimation of the annual energy savings achieved from the replacement of 20,000 refrigerators in New York City Housing Authority (NYCHA) public housing with new, highly energy-efficient models in 1997. The US Department of Housing and Urban Development (HUD) pays NYCHA`s electricity bills, and agreed to reimburse NYCHA for the cost of the refrigerator installations. Energy savings over the lifetime of the refrigerators accrue to HUD. Savings were demonstrated by a metering project and are the subject of the analysis reported here. The New York Power Authority (NYPA) identified the refrigerator with the lowest life-cycle cost, including energy consumption over its expected lifetime, through a request for proposals (RFP) issued to manufacturers for a bulk purchase of 20,000 units in 1997. The procurement was won by Maytag with a 15-ft{sup 3} top-freezer automatic-defrost refrigerator rated at 437 kilowatt-hours/year (kWh/yr). NYCHA then contracted with NYPA to purchase, finance, and install the new refrigerators, and demanufacture and recycle materials from the replaced units. The US Department of Energy (DOE) helped develop and plan the project through the ENERGY STAR{reg_sign} Partnerships program conducted by its Pacific Northwest National Laboratory (PNNL). PNNL designed the metering protocol and occupant survey used in 1997, supplied and calibrated the metering equipment, and managed and analyzed the data collected by NYPA. The objective of the 1997 metering study was to achieve a general understanding of savings as a function of refrigerator label ratings, occupant effects, indoor and compartment temperatures, and characteristics (such as size, defrost features, and vintage). The data collected in 1997 was used to construct models of refrigerator energy consumption as a function of key refrigerator and occupant characteristics.

  5. Floating loop method for cooling integrated motors and inverters using hot liquid refrigerant

    DOE Patents [OSTI]

    Hsu, John S.; Ayers, Curtis W.; Coomer, Chester; Marlino, Laura D.

    2007-03-20

    A method for cooling vehicle components using the vehicle air conditioning system comprising the steps of: tapping the hot liquid refrigerant of said air conditioning system, flooding a heat exchanger in the vehicle component with said hot liquid refrigerant, evaporating said hot liquid refrigerant into hot vapor refrigerant using the heat from said vehicle component, and returning said hot vapor refrigerant to the hot vapor refrigerant line in said vehicle air conditioning system.

  6. Membrane-Based Absorption Refrigeration Systems: Nanoengineered Membrane-Based Absorption Cooling for Buildings Using Unconcentrated Solar & Waste Heat

    SciTech Connect (OSTI)

    2010-09-01

    BEETIT Project: UFL is improving a refrigeration system that uses low quality heat to provide the energy needed to drive cooling. This system, known as absorption refrigeration system (ARS), typically consists of large coils that transfer heat. Unfortunately, these large heat exchanger coils are responsible for bulkiness and high cost of ARS. UFL is using new materials as well as system design innovations to develop nanoengineered membranes to allow for enhanced heat exchange that reduces bulkiness. UFL’s design allows for compact, cheaper and more reliable use of ARS that use solar or waste heat.

  7. Cooling system for superconducting magnet

    DOE Patents [OSTI]

    Gamble, Bruce B.; Sidi-Yekhlef, Ahmed

    1998-01-01

    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.

  8. Cooling system for superconducting magnet

    DOE Patents [OSTI]

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

    1998-12-15

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

  9. Miniaturized Air-to-Refrigerant Heat Exchangers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Miniaturized Air-to-Refrigerant Heat Exchangers 2014 Building Technologies Office Peer Review Prof. Reinhard Radermacher, raderm@umd.edu University of Maryland College Park Project Summary Timeline: Start date: 03/01/2013 Planned end date: 02/29/2016 Key Milestones 1. Heat exchanger designs/process: 6/30/14 2. Fabrication/testing of 1 kW: 9/30/14 3. Fabrication/testing of 10 kW: 9/30/2015 Budget: Total DOE $ to date: $561K Total future DOE $: $489K Target Market/Audience: Residential and

  10. Miniaturized Air-to-Refrigerant Heat Exchangers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Miniaturized Air-to-Refrigerant Heat Exchangers 2015 Building Technologies Office Peer Review Reinhard Radermacher raderm@umd.edu 20%+ Better University of Maryland College Park Project Summary Timeline: Start date: 3/1/2013 Planned end date: 2/29/2016 Key Milestones 1. Design optimization, 3/30/14 2. Fabrication/testing, 1kW prototype, 1/30/2015 3. Fabrication/testing, 10kW prototype, 9/30/2015 Budget: Total Budget: $1500K Total UMD: $1050K Total DOE $ to date for UMD: $881K Total future DOE $

  11. American Society of Heating, Refrigeration, and Air Condition Engineers

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    (ASHRAE) 2016 Annual Conference | Department of Energy American Society of Heating, Refrigeration, and Air Condition Engineers (ASHRAE) 2016 Annual Conference American Society of Heating, Refrigeration, and Air Condition Engineers (ASHRAE) 2016 Annual Conference June 25, 2016 9:00AM EDT to June 29

  12. Rare-Earth-Free Nanostructure Magnets: Rare-Earth-Free Permanent Magnets for Electric Vehicle Motors and Wind Turbine Generators: Hexagonal Symmetry Based Materials Systems Mn-Bi and M-type Hexaferrite

    SciTech Connect (OSTI)

    2012-01-01

    REACT Project: The University of Alabama is developing new iron- and manganese-based composite materials for use in the electric motors of EVs and renewable power generators that will demonstrate magnetic properties superior to todays best rare-earth-based magnets. Rare earths are difficult and expensive to refine. EVs and renewable power generators typically use rare earths to make their electric motors smaller and more powerful. The University of Alabama has the potential to improve upon the performance of current state-of-the-art rare-earth-based magnets using low-cost and more abundant materials such as manganese and iron. The ultimate goal of this project is to demonstrate improved performance in a full-size prototype magnet at reduced cost.

  13. Effect of substitutional defects on Kambersky damping in L1{sub 0} magnetic materials

    SciTech Connect (OSTI)

    Qu, T.; Victora, R. H.

    2015-02-16

    Kambersky damping, representing the loss of magnetic energy from the electrons to the lattice through the spin orbit interaction, is calculated for L1{sub 0} FePt, FePd, CoPt, and CoPd alloys versus chemical degree of order. When more substitutional defects exist in the alloys, damping is predicted to increase due to the increase of the spin-flip channels allowed by the broken symmetry. It is demonstrated that this corresponds to an enhanced density of states (DOS) at the Fermi level, owing to the rounding of the DOS with loss of long-range order. Both the damping and the DOS of the Co-based alloy are found to be less affected by the disorder. Pd-based alloys are predicted to have lower damping than Pt-based alloys, making them more suitable for high density spintronic applications.

  14. Cryogenic refrigeration requirements for superconducting insertion devices in a light source

    SciTech Connect (OSTI)

    Green, Michael A.; Green, Michael A.; Green, Michael A.

    2003-08-15

    This report discusses cryogenic cooling superconducting insertion devices for modern light sources. The introductory part of the report discusses the difference between wiggler and undulators and how the bore temperature may affect the performance of the magnets. The steps one would take to reduce the gap between the cold magnet pole are discussed. One section of the report is devoted to showing how one would calculate the heat that enters the device. Source of heat include, heat entering through the vacuum chamber, heating due to stray electrons and synchrotron radiation, heating due to image current on the bore, heat flow by conduction and radiation, and heat transfer into the cryostat through the magnet leads. A section of the report is devoted to cooling options such as small cryo-cooler and larger conventional helium refrigerators. This section contains a discussion as to when it is appropriate to use small coolers that do not have J-T circuits. Candidate small cryo-coolers are discussed in this section of the report. Cooling circuits for cooling with a conventional refrigerator are also discussed. A section of the report is devoted to vibration isolation and how this may affect how the cooling is attached to the device. Vibration isolation using straps is compared to vibration isolation using helium heat pipes. The vibration isolation of a conventional refrigeration system is also discussed. Finally, the cool down of an insertion device is discussed. The device can either be cooled down using liquid cryogenic nitrogen and liquid helium or by using the cooler used to keep the devices cold over the long haul.

  15. Analysis of Environmentally Friendly Refrigerant Options for Window Air Conditioners

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bansal, Pradeep; Shen, Bo

    2015-03-12

    This paper presents a technical assessment of environmentally friendly refrigerants as alternatives to R410A for window air conditioners. The alternative refrigerants that are studied for its replacement include R32, a mixture of R32/R125 with 90%/10% molar concentration, R600a, R290, R1234yf, R1234ze and R134a. Baseline experiments were performed on a window unit charged with R410A. The heat pump design model (HPDM) was modified and calibrated with the baseline data and was used to evaluate the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and their suitability for window air conditioners. Amongmore » all the refrigerants studied, R32 offers the best efficiency and the lowest Global Warming Potential (GWP), and hence its use will result in the overall environmental friendliness.« less

  16. Analysis of Environmentally Friendly Refrigerant Options for Window Air Conditioners

    SciTech Connect (OSTI)

    Bansal, Pradeep; Shen, Bo

    2015-01-01

    This paper presents a technical assessment of environmentally friendly refrigerants as alternatives to R410A for window air conditioners. The alternative refrigerants that are studied for its replacement include R32, a mixture of R32/R125 with 90%/10% molar concentration, R600a, R290, R1234yf, R1234ze and R134a. Baseline experiments were performed on a window unit charged with R410A. The heat pump design model (HPDM) was modified and calibrated with the baseline data and was used to evaluate the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and their suitability for window air conditioners. Among all the refrigerants studied, R32 offers the best efficiency and the lowest Global Warming Potential (GWP), and hence its use will result in the overall environmental friendliness.

  17. Modeling Supermarket Refrigeration Systems with EnergyPlus

    SciTech Connect (OSTI)

    Stovall, Therese K; Baxter, Van D

    2010-01-01

    Supermarket refrigeration capabilities were first added to EnergyPlus in 2004. At that time, it was possible to model a direct expansion (DX) rack system with multiple refrigerated cases. The basic simulation software handles all the building energy uses, typically on a 5 to 10 minute time step throughout the period of interest. The original refrigeration module included the ability to model the sensible and latent interactions between the refrigerated cases and the building HVAC system, along with some basic heat recovery capabilities. Over the last few years, the refrigeration module has been expanded to handle more complex systems, such as secondary loops, shared condensers, cascade condensers, subcoolers, and walk-in coolers exchanging energy with multiple conditioned zones.

  18. Design issues of a thermoacoustic refrigerator and its heat exchangers

    SciTech Connect (OSTI)

    Wetzel, M.; Herman, C.

    1996-12-31

    Thermoacoustic refrigeration is a fast advancing new refrigeration technology. Performance calculations indicate remarkable values for the thermoacoustic core of a thermoacoustic refrigerator. The thermoacoustic core is responsible for pumping heat from a cold to a hot temperature reservoir. However, the systems necessary to support the thermoacoustic core, such as heat exchangers and acoustic drivers are the weak points of this refrigeration technology. Particularly, heat exchangers were designed so far without any optimization. A reason for this is the lack of knowledge of the flow structures and heat transfer phenomena at the interface between the thermoacoustic core and the heat exchangers. For the purpose of gaining better insight, the authors built a thermoacoustic refrigerator model and applied visualization techniques, such as smoke injection and holographic interferometry, to visualize the flow and temperature fields at the interface.

  19. Assessment of Environmentally Friendly Refrigerants for Window Air Conditioners

    SciTech Connect (OSTI)

    Bansal, Pradeep; Shen, Bo

    2014-01-01

    This paper presents technical assessment of environmentally friendly refrigerants for window air conditioners that currently use refrigerant R410A for residential and commercial applications. The alternative refrigerants that are studied for its replacement include R32, R600a, R290, R1234yf, R1234ze and a mixture of R32 (90% molar concentration) and R125 (10% molar concentration). Baseline experiments were performed on a window unit charged with R410A. The ORNL Heat Pump Design Model was calibrated with the baseline data and was used to assess the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and their suitability for window air conditioners.

  20. Analysis of Environmentally Friendly Refrigerant Options for Window Air Conditioners

    SciTech Connect (OSTI)

    Bansal, Pradeep; Shen, Bo

    2015-03-12

    This paper presents a technical assessment of environmentally friendly refrigerants as alternatives to R410A for window air conditioners. The alternative refrigerants that are studied for its replacement include R32, a mixture of R32/R125 with 90%/10% molar concentration, R600a, R290, R1234yf, R1234ze and R134a. Baseline experiments were performed on a window unit charged with R410A. The heat pump design model (HPDM) was modified and calibrated with the baseline data and was used to evaluate the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and their suitability for window air conditioners. Among all the refrigerants studied, R32 offers the best efficiency and the lowest Global Warming Potential (GWP), and hence its use will result in the overall environmental friendliness.

  1. New technologies for refrigeration without CFCs

    SciTech Connect (OSTI)

    Swift, G.W.

    1992-09-01

    Today the appliance industry and other cooling industries are facing the double challenge of eliminating environmentally harmful CFCs while simultaneously improving energy efficiency. These challenges will force this industry to make tremendous changes and to work out many difficult problems, ranging from choice of technology through production-line retooling to product-liability concerns. Three new cooling technologies--sonic compression, thermoacoustic refrigeration, and Malone refrigeration--have been developed at least in part at Los Alamos National Laboratory. We will discuss the principles, features, and status of each of these three technologies. With these three examples we hope to show that mechanical compression and subsequent evaporation of CFCs is not the only potentially practical way to produce cooling. These examples are only three of many alternative cooling technologies. No new technology can be guaranteed a success before development is complete, from either an economic or engineering point of view. But enough alternative cooling technologies exist, and the probability for success of each technology is high enough, that one or more of these technologies can almost certainly be produced at reasonable cost, eliminate CFCS, and reduce the consumption of electricity.

  2. Sublattice Magnetic Relaxation in Rare Earth Iron Garnets

    SciTech Connect (OSTI)

    McCloy, John S.; Walsh, Brian

    2013-07-08

    The magnetic properties of rare earth garnets make them attractive materials for applications ranging from optical communications to magnetic refrigeration. The purpose of this research was to determine the AC magnetic properties of several rare earth garnets, in order to ascertain the contributions of various sublattices. Gd3Fe5O¬12, Gd3Ga5O12, Tb3Fe5O12, Tb3Ga5O12, and Y3Fe5O12 were synthesized by a solid state reaction of their oxides and verified by x-ray diffraction. Frequency-dependent AC susceptibility and DC magnetization were measured versus temperature (10 – 340 K). Field cooling had little effect on AC susceptibility, but large effect on DC magnetization, increasing magnetization at the lowest temperature and shifting the compensation point to lower temperatures. Data suggest that interaction of the two iron lattices results in the two frequency dependent magnetic relaxations in the iron garnets, which were fit using the Vogel-Fulcher and Arrhenius laws.

  3. The Prospects of Alternatives to Vapor Compression Technology for Space Cooling and Food Refrigeration Applications

    SciTech Connect (OSTI)

    Brown, Daryl R.; Stout, Tyson E.; Dirks, James A.; Fernandez, Nicholas

    2012-12-01

    This article identifies and describes five alternative cooling technologies (magnetic, thermionic, thermoacoustic, thermoelectric, and thermotunnel) and qualitatively assesses the prospects of each technology relative to vapor compression for space cooling and food refrigeration applications. Assessment of the alternatives was based on the theoretical maximum % of Carnot efficiency, the current state of development, the best % of Carnot efficiency currently achieved, developmental barriers, and the extent of development activity. The prospect for each alternative was assigned an overall qualitative rating based on the subjective, composite view of the five characteristics.

  4. Shape Memory Alloys and Their Applications in Power Generation and Refrigeration

    SciTech Connect (OSTI)

    Cui, Jun

    2013-03-27

    The shape memory effect is closely related to the reversible martensitic phase transformation, which is diffusionless and involves shear deformation. The recoverable transformation between the two phases with different crystalline symmetry results in reversible changes in physical properties such as electrical conductivity, magnetization, and elasticity. Accompanying the transformation is a change of entropy. Fascinating applications are developed based on these changes. In this paper, the history, fundamentals and technical challenges of both thermoelastic and ferromagnetic shape memory alloys are briefly reviewed; applications related to energy conversion such as power generation and refrigeration as well as recent developments will be discussed.

  5. Shape Memory Alloys and their Applications in Power Generation and Refrigeration

    SciTech Connect (OSTI)

    Cui, Jun

    2013-07-01

    The shape memory effect is closely related to the reversible martensitic phase transformation, which is diffusionless and involves shear deformation. The recoverable transformation between the two phases with different crystalline symmetry results in reversible changes in physical properties such as electrical conductivity, magnetization, and elasticity. Accompanying the transformation is a change of entropy. Fascinating applications are developed based on these changes. In this paper, the history, fundamentals and technical challenges of both thermoelastic and ferromagnetic shape memory alloys are briefly reviewed; applications related to energy conversion such as power generation and refrigeration as well as recent developments will be discussed.

  6. An Evaluation of the Environmental Impact of Different Commercial Supermarket Refrigeration Systems Using Low Global Warming Potential Refrigerants

    SciTech Connect (OSTI)

    Beshr, Mohamed; Aute, Vikrant; Abdelaziz, Omar; Fricke, Brian A; Radermacher, Reinhard

    2014-01-01

    Commercial refrigeration systems consumed 1.21 Quads of primary energy in 2010 and are known to be a major source for refrigerant charge leakage into the environment. Thus, it is important to study the environmental impact of commercial supermarket refrigeration systems and improve their design to minimize any adverse impacts. The system s Life Cycle Climate Performance (LCCP) was presented as a comprehensive metric with the aim of calculating the equivalent mass of carbon dioxide released into the atmosphere throughout its lifetime, from construction to operation and destruction. In this paper, an open source tool for the evaluation of the LCCP of different air-conditioning and refrigeration systems is presented and used to compare the environmental impact of a typical multiplex direct expansion (DX) supermarket refrigeration systems based on three different refrigerants as follows: two hydrofluorocarbon (HFC) refrigerants (R-404A, and R-407F), and a low global warming potential (GWP) refrigerant (N-40). The comparison is performed in 8 US cities representing different climates. The hourly energy consumption of the refrigeration system, required for the calculation of the indirect emissions, is calculated using a widely used building energy modeling tool (EnergyPlus). A sensitivity analysis is performed to determine the impact of system charge and power plant emission factor on the LCCP results. Finally, we performed an uncertainty analysis to determine the uncertainty in total emissions for both R-404A and N-40 operated systems. We found that using low GWP refrigerants causes a considerable drop in the impact of uncertainty in the inputs related to direct emissions on the uncertainty of the total emissions of the system.

  7. Sub-Kelvin magnetic and electrical measurements in a diamond anvil cell with in-situ tunability

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Palmer, Alexander; Silevitch, Daniel; Feng, Yejun; Wang, Yishu; Jaramillo, R.; Banerjee, Arnab; Ren, Yang; Rosenbaum, Thomas F.

    2015-09-04

    We discuss techniques for performing continuous measurements across a wide range of pressure-field-temperature phase space, combining the milli-Kelvin temperatures of a helium dilution refrigerator with that of the giga-Pascal pressures of a diamond anvil cell and the Tesla magnetic fields of a superconducting magnet. With a view towards minimizing remnant magnetic fields and background magnetic susceptibility, we then characterize high-strength superalloy materials for the pressure cell assembly, which allows high fidelity measurements of low-field phenomena such as superconductivity below 100 mK at pressures above 10 GPa. In situ tunability and measurement of the pressure permit experiments over a wide rangemore » of pressure, while at the same time making possible precise steps across abrupt phase transitions such as that from insulator to metal.« less

  8. Sub-Kelvin magnetic and electrical measurements in a diamond anvil cell with in-situ tunability

    SciTech Connect (OSTI)

    Palmer, Alexander; Silevitch, Daniel; Feng, Yejun; Wang, Yishu; Jaramillo, R.; Banerjee, Arnab; Ren, Yang; Rosenbaum, Thomas F.

    2015-09-04

    We discuss techniques for performing continuous measurements across a wide range of pressure-field-temperature phase space, combining the milli-Kelvin temperatures of a helium dilution refrigerator with that of the giga-Pascal pressures of a diamond anvil cell and the Tesla magnetic fields of a superconducting magnet. With a view towards minimizing remnant magnetic fields and background magnetic susceptibility, we then characterize high-strength superalloy materials for the pressure cell assembly, which allows high fidelity measurements of low-field phenomena such as superconductivity below 100 mK at pressures above 10 GPa. In situ tunability and measurement of the pressure permit experiments over a wide range of pressure, while at the same time making possible precise steps across abrupt phase transitions such as that from insulator to metal.

  9. Refrigeration Recovery for Experiment Hall High Target Loads

    SciTech Connect (OSTI)

    Peter Knudsen, Venkatarao Ganni, Errol Yuksek, Jonathan Creel

    2010-04-01

    The Qweak experiment at Jefferson Lab (JLab) is a 3000 W hydrogen target scheduled for the summer of 2010 and running for two years until the planned shut-down for 12GeV. The End Station Refrigerator (ESR) supports the three experiment halls, two of which may normally have a hydrogen target. The refrigerator for the ESR is a CTI/Helix 1500 W 4.5-K refrigerator nominally capable of supporting a 1250 W target load at 12 bar and 15-K (plus 1100 W of 4.5-K refrigeration). As such, this refrigerator is not capable of supporting the Qweak experiment target load in its present condition. Additionally, since the installation of an ambient air vaporizer for a single use, two week run duration of a high target load in the summer of 2003 there has been a consistent usage of the Central Helium Liquefier’s (CHL’s) 3 bar 4.5-K helium, supplied via an existing transfer-line to the ESR, for other high target loads. By the fall of 2004, it was apparent that this continued use of CHL’s supercritical helium was routinely being sought by the hall experimenters. As such, a method of refrigeration recovery was proposed to reduce the support required of CHL for these high target loads, including the anticipated Qweak experiment, while utilizing the recovered CHL refrigeration from the target to increase ESR’s 12 bar 15-K capacity.

  10. Energy Efficiency and Environmental Impact Analyses of Supermarket Refrigeration Systems

    SciTech Connect (OSTI)

    Fricke, Brian A; Bansal, Pradeep; Zha, Shitong

    2013-01-01

    This paper presents energy and life cycle climate performance (LCCP) analyses of a variety of supermarket refrigeration systems to identify designs that exhibit low environmental impact and high energy efficiency. EnergyPlus was used to model refrigeration systems in a variety of climate zones across the United States. The refrigeration systems that were modeled include the traditional multiplex DX system, cascade systems with secondary loops and the transcritical CO2 system. Furthermore, a variety of refrigerants were investigated, including R-32, R-134a, R-404A, R-1234yf, R-717, and R-744. LCCP analysis was used to determine the direct and indirect carbon dioxide emissions resulting from the operation of the various refrigeration systems over their lifetimes. Our analysis revealed that high-efficiency supermarket refrigeration systems may result in up to 44% less energy consumption and 78% reduced carbon dioxide emissions compared to the baseline multiplex DX system. This is an encouraging result for legislators, policy makers and supermarket owners to select low emission, high-efficiency commercial refrigeration system designs for future retrofit and new projects.

  11. ISSUANCE 2015-10-20: Energy Conservation Program: Energy Conservation Standards for Refrigerated Beverage Vending Machines

    Broader source: Energy.gov [DOE]

    Energy Conservation Program: Energy Conservation Standards for Refrigerated Beverage Vending Machines

  12. Functional Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Functional Materials Researchers in NETL's Functional Materials Development competency work to discover and develop advanced functional materials and component processing technologies to meet technology performance requirements and enable scale-up for proof-of-concept studies. Research includes separations materials and electrochemical and magnetic materials, specifically: Separations Materials Synthesis, purification, and basic characterization of organic substances, including polymers and

  13. Spray generators for absorption refrigeration systems

    DOE Patents [OSTI]

    Sibley, Howard W.

    1979-06-19

    A spray generator for an absorption refrigeration system that includes a heat exchanger comprised of a multiplicity of variably spaced heat exchange tubes. The tubes are spaced close together near the top of the heat exchanger and spaced more widely apart near the bottom of the heat exchanger. Dilute absorbent solution is sprayed down through the heat exchanger. The close nesting of the tubes in the top portion of the heat exchanger retards liquid flow and aids heating of the solution. The wide spacing of the tubes in the lower section of the heat exchanger facilitate vapor flow out of the heat exchanger and eliminates liquid "blow-off". The top tubes are covered by a baffle to prevent the liquid solution from splashing out of the heat exchanger off of these top tubes.

  14. Alternative technologies for cooling and refrigeration equipment

    SciTech Connect (OSTI)

    Matchett, J.

    1995-12-01

    Significant national and international attention has focused on the role that chlorofluorocarbons (CFCs) play in stratospheric ozone depletion. The Clean Air Act of 1990 calls for the production of the most harmful CFCs to completely cease by December 31, 1995. This production phaseout affects many CFC-refrigerants which are commonly used in commercial, residential, and industrial cooling processes. The production phaseout of CFCs will require owners of CFC-based refrigeration equipment to make plans to replace their equipment. Many equipment owners find themselves in a {open_quotes}rut{close_quotes}replacing CFCs with another chemical coolant, rather than a new cooling process. Since many of the chemical alternatives are structurally similar to CFCs (i.e., HCFCs, HFCs, and blends) they require minimal changes to current equipment. However, these substances are also believed to affect the global climate. Hence, they may not be the most environmentally sound alternative and probable are subject to other Federal regulations. There are other HVAC/R alternatives which are less environmentally damaging than these chemicals and may actually be more cost-effective and energy efficient and than the {open_quotes}traditional{close_quotes} CFC chemical substitutes. Alternative cooling technologies include absorption systems, desiccant cooling, evaporative cooling, and ammonia vapor compression. These alternative technologies are proven alternatives and are commercially available. Further, significant technological developments in recent years have made these technologies feasible alternatives for applications previously believed to be unacceptable. This paper describes these alternative technologies and the conditions in which they are viable alternatives to CFC-based equipment. Additionally, energy efficiency and life-cycle cost analysis considerations are addressed to provide a more completes analysis of cooling equipment alternatives.

  15. Combined refrigeration system with a liquid pre-cooling heat exchanger

    DOE Patents [OSTI]

    Gaul, Christopher J.

    2003-07-01

    A compressor-pump unit for use in a vapor-compression refrigeration system is provided. The compressor-pump unit comprises a driving device including a rotatable shaft. A compressor is coupled with a first portion of the shaft for compressing gaseous refrigerant within the vapor-compression refrigeration system. A liquid pump is coupled with a second portion of the shaft for receiving liquid refrigerant having a first pressure and for discharging the received liquid refrigerant at a second pressure with the second pressure being higher than the first pressure by a predetermined amount such that the discharged liquid refrigerant is subcooled. A pre-cooling circuit is connected to the liquid pump with the pre-cooling circuit being exposed to the gaseous refrigerant whereby the gaseous refrigerant absorbs heat from the liquid refrigerant, prior to the liquid refrigerant entering the liquid pump.

  16. Development of Refrigerant Change Indicator and Dirty Air Filter Sensor

    SciTech Connect (OSTI)

    Mei, V.

    2003-06-24

    The most common problems affecting residential and light commercial heating, ventilation, and air-conditioning (HVAC) systems are slow refrigerant leaks and dirty air filters. Equipment users are usually not aware of a problem until most of the refrigerant has escaped or the air filter is clogged with dirt. While a dirty air filter can be detected with a technology based on the air pressure differential across the filter, such as a ''whistling'' indicator, it is not easy to incorporate this technology into existing HVAC diagnostic equipment. Oak Ridge National Laboratory is developing a low-cost, nonintrusive refrigerant charge indicator and dirty air filter detection sensor. The sensors, based on temperature measurements, will be inexpensive and easy to incorporate into existing heat pumps and air conditioners. The refrigerant charge indicator is based on the fact that when refrigerant starts to leak, the evaporator coil temperature starts to drop and the level of liquid subcooling drops. When the coil temperature or liquid subcooling drops below a preset reading, a signal, such as a yellow warning light, can be activated to warn the equipment user that the system is undercharged. A further drop of coil temperature or liquid subcooling below another preset reading would trigger a second warning signal, such as a red warning light, to warn the equipment user that the unit now detects a leak and immediate action should be taken. The warning light cannot be turned off until it is re-set by a refrigeration repairman. To detect clogged air filters, two additional temperature sensors can be applied, one each across the evaporator. When the air filter is accumulating buildup, the temperature differential across the evaporator will increase because of the reduced airflow. When the temperature differential reaches a pre-set reading, a signal will be sent to the equipment user that the air filter needs to be changed. A traditional refrigerant charge indicator requires intrusion into the system to measure the refrigerant high-side and low-side pressures. Once the pressures are known, based on the equipment's refrigerant charging chart? or in most cases, based on the technician's experience? the refrigerant charging status is determined. However, there is a catch: by the time a refrigeration technician is called, most of the refrigerant has already escaped into the atmosphere. The new technology provides a real-time warning so that when, say, 20% of the refrigerant has leaked, the equipment users will be warned, even though the equipment is still functioning properly at rated capacity. Temperature sensors are becoming very accurate and very low in cost, compared with pressure sensors. Using temperature sensors to detect refrigerant charge status is inherently nonintrusive, inexpensive, and accurate. With the addition of two temperature sensors for detecting dirty air filters, the capability of the diagnostic equipment is further enhanced with very little added cost. This report provides laboratory test data on the change of indoor coil refrigerant temperature and subcooling as a function of refrigerant charge for a 2-ton split heat pump system. The data can be used in designing the indicators for refrigerant loss and dirty air filter sensors.

  17. Comprehensive Compressor Calorimeter Testing of Lower-GWP Alternative Refrigerants for Heat Pump and Medium Temperature Refrigeration Applications

    SciTech Connect (OSTI)

    Shrestha, Som S; Sharma, Vishaldeep; Abdelaziz, Omar

    2014-01-01

    In response to environmental concerns raised by the use of refrigerants with high Global Warming Potential (GWP), the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) has launched an industry-wide cooperative research program, referred to as the Low-GWP Alternative Refrigerants Evaluation Program (AREP), to identify and evaluate promising alternative refrigerants for major product categories. This paper reports one of the Oak Ridge National Laboratory (ORNL) contributions to AREP. It compares performance of alternative refrigerants to that of R-410A and R-404A for heat pump and medium temperature applications, respectively. The alternatives reported in this paper are: R-32, DR-5, and L-41a for R-410A and ARM-31a, D2Y-65, L-40, and a mixture of R-32 and R-134a for R-404A. All performance comparison tests were conducted using scroll compressors of ~1.85 tons (6.5 kW) cooling capacity. Tests were conducted over a range of combinations of saturation suction and saturation discharge temperatures for both compressors. The tests showed that, in general, energy efficiency ratio (EER) and cooling capacity of R-410A alternative refrigerants were slightly lower than that of the baseline refrigerant with a moderate increases in discharge temperature. On the other hand, R-404A alternative refrigerants showed relative performance dependence on saturation suction and saturation discharge temperatures and larger increases in discharge temperature than for the R-410A alternatives. This paper summarizes the relative performance of all alternative refrigerants compared to their respective baseline.

  18. VEE-0079 - In the Matter of Diversified Refrigeration, Inc. | Department of

    Office of Environmental Management (EM)

    Energy 9 - In the Matter of Diversified Refrigeration, Inc. VEE-0079 - In the Matter of Diversified Refrigeration, Inc. Diversified Refrigeration, Inc. (DRI) requests a six-month exception from the 2001 energy appliance efficiency standards for built-in refrigerators that become effective July 1, 2001. As explained below, we are granting DRI a six-month exception - from July 1, 2001 to December 31, 2001 - that permits the firm to produce a specific number of non-compliant refrigerators per

  19. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Conversely, introducing a magnetic field to certain materials will cause the material to heat up. This happens because, as the spins in such (paramagnetic) materials align with...

  20. Mineral Magnetism

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mineral Magnetism 1663 Los Alamos science and technology magazine Latest Issue:March 2016 past issues All Issues » submit Mineral Magnetism By understanding what makes a material magnetic, scientists want to create new strongly magnetic materials that don't rely on hard-to-get precursor elements. March 8, 2016 Small piles of rare earth elements In the United States, rare-earth elements used in strong magnets, such as neodymium and samarium, are scarce due to limits on foreign sources. CREDIT:

  1. 2015-03-26: Miscellaneous Refrigeration Products; Notice of Intent...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    to Establish an ASRAC Working Group 2015-03-26: Miscellaneous Refrigeration Products; Notice of Intent to Establish an ASRAC Working Group This document is a pre-publication ...

  2. DOE Opens Three Investigations into Alleged Refrigerator Efficiency Violations

    Broader source: Energy.gov [DOE]

    The Department of Energy has issued one subpoena and two data requests to three companies in response to allegations that the companies are selling refrigerator-freezers that failed to meet federal...

  3. Duracold Refrigeration Manufacturing: Proposed Penalty (2013-CE-5342)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Duracold Refrigeration Manufacturing Company, LLC failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

  4. New Refrigerant Boosts Energy Efficiency of Supermarket Display Cases

    Broader source: Energy.gov [DOE]

    Research supported by the Energy Departments Building Technologies Office has led to a major breakthrough in refrigeration systems efficiency, and the result may yield big energy savings for...

  5. Commercial Refrigerator Door: Proposed Penalty (2013-CE-5351)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that Commercial Refrigerator Door Company, Inc. failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

  6. Property:Building/SPElectrtyUsePercRefrigeration | Open Energy...

    Open Energy Info (EERE)

    yUsePercRefrigeration" Showing 25 pages using this property. (previous 25) (next 25) S Sweden Building 05K0001 + 0.0 + Sweden Building 05K0002 + 0.0 + Sweden Building 05K0003 + 0.0...

  7. Synchronous temperature rate control for refrigeration with reduced energy consumption

    DOE Patents [OSTI]

    Gomes, Alberto Regio; Keres, Stephen L.; Kuehl, Steven J.; Litch, Andrew D.; Richmond, Peter J.; Wu, Guolian

    2015-09-22

    Methods of operation for refrigerator appliance configurations with a controller, a condenser, at least one evaporator, a compressor, and two refrigeration compartments. The configuration may be equipped with a variable-speed or variable-capacity compressor, variable speed evaporator or compartment fans, a damper, and/or a dual-temperature evaporator with a valve system to control flow of refrigerant through one or more pressure reduction devices. The methods may include synchronizing alternating cycles of cooling each compartment to a temperature approximately equal to the compartment set point temperature by operation of the compressor, fans, damper and/or valve system. The methods may also include controlling the cooling rate in one or both compartments. Refrigeration compartment cooling may begin at an interval before or after when the freezer compartment reaches its lower threshold temperature. Freezer compartment cooling may begin at an interval before or after when the freezer compartment reaches its upper threshold temperature.

  8. Commissioning and operation of the CEBAF end station refrigeration system

    SciTech Connect (OSTI)

    Arenius, D.; Bevins, B.; Chronis, W.C.; Ganni, V.; Kashy, D.; Keesee, M.; Wilson, J. Jr.

    1996-08-01

    The CEBAF End Station Helium Refrigerator (ESR) System provides refrigeration at 80 K, 20 K and 4.5 K to three End Station experimental halls. The facility consists of a two stage helium screw compressor system, 4.5 K refrigerator, cryogen distribution valve box, and transfer lines to the individual experimental halls. The 4.5 K cold box and compressors were originally part of the ESCAR 1,500 W, 4 K refrigeration system at Lawrence Berkeley Laboratory which was first commissioned fin 1977. The compressors, 4.5 K cold box, and control system design were modified to adapt the plant for the requirements of the CEBAF experimental halls. Additional subsystems of cryogen distribution, transfer lines, warm gas management, and computer control interface were added. This paper describes the major plant subsystems, modifications, operational experiences and performance.

  9. North Star Refrigerator: Proposed Penalty (2013-CE-5355)

    Broader source: Energy.gov [DOE]

    DOE alleged in a Notice of Proposed Civil Penalty that North Star Refrigerator Co., Inc. failed to certify a variety of walk-in cooler or freezer components as compliant with the applicable energy conservation standards.

  10. DOE Closes Investigation into Energy Efficiency of Viking Refrigerator

    Broader source: Energy.gov [DOE]

    The Department of Energy has closed its investigation into the energy efficiency of Viking Range Corporation’s refrigerator-freezer model VCSB542.  The Department initiated this investigation in...

  11. National Weatherization Assistance Program Evaluation: Assessment of Refrigerator Energy Use

    SciTech Connect (OSTI)

    Tonn, Bruce Edward; Goeltz, Rick

    2015-03-01

    This report assesses the energy consumption characteristics and performance of refrigerators that were monintored as a component of the Indoor Air Quality Study that itself was a component of the retrospective evaluation of the Department of Energy's Weatherization Assistance Program.

  12. Development and Evaluation of a Sandia Cooler-based Refrigerator...

    Office of Environmental Management (EM)

    This report describes the first design of a refrigerator condenser using the Sandia Cooler, i.e. air-bearing supported rotating heat-sink impeller. The project included baseline ...

  13. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, J.A.; Stone, R.R.; Fabyan, J.

    1987-10-06

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines. 3 figs.

  14. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, John A.; Stone, Roger R.; Fabyan, Joseph

    1987-01-01

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

  15. Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Refrigerants Thermodynamic Evaluation of Low-Global Warming Potential Refrigerants Credit: National Institute of Standards Credit: National Institute of Standards Lead Performer: National Institute of Standards and Technology - Gaithersburg, MD Partners: -- Catholic University of America - Washington, DC -- George Mason University - Fairfax, VA DOE Funding: $1,750,000 Cost Share: N/A Project Term: 2/1/2011 - 3/31/2015 Project Objective This project evaluates alternative

  16. Natural Refrigerant High-Performance Heat Pump for Commercial Applications

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy Refrigerant High-Performance Heat Pump for Commercial Applications Natural Refrigerant High-Performance Heat Pump for Commercial Applications Credit: S-RAM Credit: S-RAM Lead Performer: S-RAM - Franklin, TN Partners: -- Oak Ridge National Laboratory - Oak Ridge, TN -- Purdue University - West Lafayette, IN -- ReGen Power - Canning Vale, Western Australia DOE Funding: $400,000 Cost Share: $125,000 Project Term: December 2013 - December 2017 Funding Opportunity: Building

  17. Alternative Refrigerant Evaluation for High-Ambient-Temperature

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners | Department of Energy Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners The Oak Ridge National Laboratory High-Ambient-Temperature Evaluation Program for Low Global Warming Potential (Low-GWP)

  18. BTO Partners are Revolutionizing Refrigerators and Clothes Dryers |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Partners are Revolutionizing Refrigerators and Clothes Dryers BTO Partners are Revolutionizing Refrigerators and Clothes Dryers April 14, 2015 - 3:18pm Addthis Oak Ridge National Lab’s Ayyoub Momen demonstrates ultrasonic clothes dryer technology for David Danielson, Assistant Secretary for Energy Efficiency and Renewable Energy (EERE) Oak Ridge National Lab's Ayyoub Momen demonstrates ultrasonic clothes dryer technology for David Danielson, Assistant Secretary for

  19. New Energy Efficiency Standards for Commercial Refrigeration Equipment to

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Cut Businesses' Energy Bills and Carbon Pollution | Department of Energy Commercial Refrigeration Equipment to Cut Businesses' Energy Bills and Carbon Pollution New Energy Efficiency Standards for Commercial Refrigeration Equipment to Cut Businesses' Energy Bills and Carbon Pollution February 28, 2014 - 10:45am Addthis News Media Contact (202) 586-4940 WASHINGTON - Building on President Obama's State of the Union address and the Administration's Climate Action Plan, the Energy Department

  20. DOE Reaches Agreement with LG Electronics, USA, On Refrigerator Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Matter | Department of Energy Reaches Agreement with LG Electronics, USA, On Refrigerator Energy Matter DOE Reaches Agreement with LG Electronics, USA, On Refrigerator Energy Matter November 14, 2008 - 4:47pm Addthis ENERGY STAR® Program Continues to Help American Consumers Make Energy Efficient Choices WASHINGTON - The U.S. Department of Energy (DOE) today announced an agreement with LG Electronics, USA, Inc. (LG), resolving concerns related to energy usage measurements reported on LG

  1. REA Refrigerated Display Case LED Lighting Performance Specification |

    Energy Savers [EERE]

    Department of Energy REA Refrigerated Display Case LED Lighting Performance Specification REA Refrigerated Display Case LED Lighting Performance Specification A Retailer Energy Alliances (REA) Project PDF icon rea_refrig_display_spec.pdf More Documents & Publications CBEA LED Site Lighting Specification - Version 1.3, Released 2/15/2012 Model Specification for LED Roadway Luminaires, V2.0 CBEA High-Efficiency Parking Structure Lighting Specification

  2. Heat exchanger bypass system for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C.

    1984-01-01

    A heat exchanger bypass system for an absorption refrigeration system is disclosed. The bypass system operates to pass strong solution from the generator around the heat exchanger to the absorber of the absorption refrigeration system when strong solution builds up in the generator above a selected level indicative of solidification of strong solution in the heat exchanger or other such blockage. The bypass system includes a bypass line with a gooseneck located in the generator for controlling flow of strong solution into the bypass line and for preventing refrigerant vapor in the generator from entering the bypass line during normal operation of the refrigeration system. Also, the bypass line includes a trap section filled with liquid for providing a barrier to maintain the normal pressure difference between the generator and the absorber even when the gooseneck of the bypass line is exposed to refrigerant vapor in the generator. Strong solution, which may accumulate in the trap section of the bypass line, is diluted, to prevent solidification, by supplying weak solution to the trap section from a purge system for the absorption refrigeration system.

  3. Parameter spaces and design optimization of thermoacoustic refrigerators

    SciTech Connect (OSTI)

    Wetzel, M.; Herman, C.

    1996-12-31

    In the last two decades thermoacoustic refrigerators were developed in research laboratories with the goal to understand the basic physics and thermodynamics of thermoacoustic heat pumping. These research efforts led to a good understanding of this new environmentally safe refrigeration technology that employs acoustic power to pump heat. Consequently the next step is to improve and optimize the performance of thermoacoustic refrigerators and seek commercial applications. For this purpose, the need for fast and simple engineering estimates arises. By implementing the simplified linear model of thermoacoustic refrigerators--the short stack boundary layer approximation--such design estimates were derived and presented in this paper in the form of a design algorithm. Calculations obtained with this algorithm predict values for the Coefficient Of Performance (COP) of the order of 5 to 6. These values cannot be achieved at this time because of loss mechanisms in key parts of the thermoacoustic refrigerator, which are not quite understood yet. Nevertheless, these values are encouraging and gaining a better understanding of these loss mechanisms will be a big step towards the commercial market for this new environmentally safe refrigeration technology.

  4. Heat pump employing optimal refrigerant compressor for low pressure ratio applications

    DOE Patents [OSTI]

    Ecker, Amir L.

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler for circulating the fluid in heat exchange relationship with a refrigerant fluid; two refrigerant heat exchangers; one for effecting the heat exchange with the fluid and a second refrigerant-heat exchange fluid heat exchanger for effecting a low pressure ratio of compression of the refrigerant; a rotary compressor for compressing the refrigerant with low power consumption at the low pressure ratio; at least one throttling valve connecting at the inlet side of heat exchanger in which liquid refrigerant is vaporized; a refrigerant circuit serially connecting the above elements; refrigerant in the circuit; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant.

  5. Organic Light-Emitting Diodes (OLEDs) and Optically-Detected Magnetic Resonance (ODMR) studies on organic materials

    SciTech Connect (OSTI)

    Cai, Min

    2011-11-30

    Organic semiconductors have evolved rapidly over the last decades and currently are considered as the next-generation technology for many applications, such as organic light-emitting diodes (OLEDs) in flat-panel displays (FPDs) and solid state lighting (SSL), and organic solar cells (OSCs) in clean renewable energy. This dissertation focuses mainly on OLEDs. Although the commercialization of the OLED technology in FPDs is growing and appears to be just around the corner for SSL, there are still several key issues that need to be addressed: (1) the cost of OLEDs is very high, largely due to the costly current manufacturing process; (2) the efficiency of OLEDs needs to be improved. This is vital to the success of OLEDs in the FPD and SSL industries; (3) the lifetime of OLEDs, especially blue OLEDs, is the biggest technical challenge. All these issues raise the demand for new organic materials, new device structures, and continued lower-cost fabrication methods. In an attempt to address these issues, we used solution-processing methods to fabricate highly efficient small molecule OLEDs (SMOLEDs); this approach is costeffective in comparison to the more common thermal vacuum evaporation. We also successfully made efficient indium tin oxide (ITO)-free SMOLEDs to further improve the efficiency of the OLEDs. We employed the spin-dependent optically-detected magnetic resonance (ODMR) technique to study the luminescence quenching processes in OLEDs and organic materials in order to understand the intrinsic degradation mechanisms. We also fabricated polymer LEDs (PLEDs) based on a new electron-accepting blue-emitting polymer and studied the effect of molecular weight on the efficiency of PLEDs. All these studies helped us to better understand the underlying relationship between the organic semiconductor materials and the OLEDs performance, and will subsequently assist in further enhancing the efficiency of OLEDs. With strongly improved device performance (in addition to other OLEDs' attributes such as mechanical flexibility and potential low cost), the OLED technology is promising to successfully compete with current technologies, such as LCDs and inorganic LEDs.

  6. Magnetic shielding

    DOE Patents [OSTI]

    Kerns, J.A.; Stone, R.R.; Fabyan, J.

    1985-02-12

    A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

  7. Magnetic Materials (MM)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Contacts Calendars Community Scientific Access Site Access Training Science & Education Science & Research Highlights Conferences Seminars Publications Annual Reports APS Upgrade...

  8. Magnetic Materials Group - Staff

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    davegag@aps.anl.gov Visiting Scientists, Post-Docs, & Students Lawrie Skinner Rick Weber Vladimir Stoica Lawrie Skinner Research Asst. Prof. Stony Brook 432B003 (630)...

  9. DEVELOPMENT OF A REFRIGERANT DISTRIBUTION SECTION FOR ASHRAE STANDARD 152.

    SciTech Connect (OSTI)

    ANDREWS,J.W.

    2001-09-07

    In a recent draft report titled ''Impacts of Refrigerant Line Length on System Efficiency in Residential Heating and Cooling Systems Using Refrigerant Distribution,'' (Andrews 2000) some baseline calculations were performed to estimate various impacts on system efficiency of long refrigerant distribution lines. Refrigerant distribution refers to ''mini-splits'' and other types of space beating and cooling equipment that utilize refrigerant lines, rather than ducts or pipes, to transport heat and cooling effect from the outdoor unit to the building spaces where this heat or cooling is used. Five factors affecting efficiency were studied in each of the space conditioning modes (heating and cooling) for a total of ten factors in all. Temperature changes and pressure drops in each of the two refrigerant lines accounted for four of the factors, with the remaining one being elevation of the indoor unit relative to the outdoor unit. Of these factors, pressure drops in the suction line in cooling showed by far the largest effect. This report builds on these baseline calculations to develop a possible algorithm for a refrigerant distribution section of ASHRAE Standard 152. It is based on the approximate treatment of the previous report, and is therefore subject to error that might be corrected using a more detailed analysis, possibly including computer modeling and field testing. However, because the calculated efficiency impacts are generally small (a few percent being typical) it may be that the approximate treatment is sufficient. That question is left open for discussion. The purpose of this report is not to advocate the adoption of the methodology developed, but rather to present it as an option that could either be adopted as-is or used as a starting point for further analysis. It is assumed that the reader has available and is familiar with ASHRAE Standard 152P and with the previous analysis referred to above.

  10. Method of removing an immiscible lubricant from a refrigeration system and apparatus for same

    DOE Patents [OSTI]

    Spauschus, Hans O.; Starr, Thomas L.

    1999-01-01

    A method of separating an immiscible lubricant from a liquid refrigerant in a refrigerating system including a compressor, a condenser, an expansion device and an evaporator, wherein the expansion device is connected to the condenser by a liquid refrigerant flow line for liquid refrigerant and immiscible lubricant. The method comprising slowing the rate of flow of the liquid refrigerant and immiscible lubricant between the condenser and the expansion device such that the liquid refrigerant and the immiscible lubricant separate based upon differences in density. The method also comprises collecting the separated immiscible lubricant in a collection chamber in fluid communication with the separated immiscible lubricant. Apparatus for performing the method is also disclosed.

  11. Magnetic field-induced phase transformation in NiMnCoIn magnetic shape memory alloys - a new actuation mechanism with large work output.

    SciTech Connect (OSTI)

    Karaca, H. E.; Karaman, I.; Basaran, B.; Ren, Y.; Chumlyakov, Y. I.; Maier, H. J.; X-Ray Science Division; Texsas A&M Univ.; Univ. of Kentucky; Siberian Physical-Technical Inst.; Univ. of Paderborn

    2009-04-09

    Magnetic shape memory alloys (MSMAs) have recently been developed into a new class of functional materials that are capable of magnetic-field-induced actuation, mechanical sensing, magnetic refrigeration, and energy harvesting. In the present work, the magnetic field-induced martensitic phase transformation (FIPT) in Ni{sub 45}Mn{sub 36.5}Co{sub 5}In{sub 13.5} MSMA single crystals is characterized as a new actuation mechanism with potential to result in ultra-high actuation work outputs. The effects of the applied magnetic field on the transformation temperatures, magnetization, and superelastic response are investigated. The magnetic work output of NiMnCoIn alloys is determined to be more than 1 MJ m{sup -3} per Tesla, which is one order of magnitude higher than that of the most well-known MSMAs, i.e., NiMnGa alloys. In addition, the work output of NiMnCoIn alloys is orientation independent, potentially surpassing the need for single crystals, and not limited by a saturation magnetic field, as opposed to NiMnGa MSMAs. Experimental and theoretical transformation strains and magnetostress levels are determined as a function of crystal orientation. It is found that [111]-oriented crystals can demonstrate a magnetostress level of 140 MPa T{sup -1} with 1.2% axial strain under compression. These field-induced stress and strain levels are significantly higher than those from existing piezoelectric and magnetostrictive actuators. A thermodynamical framework is introduced to comprehend the magnetic energy contributions during FIPT. The present work reveals that the magnetic FIPT mechanism is promising for magnetic actuation applications and provides new opportunities for applications requiring high actuation work-outputs with relatively large actuation frequencies. One potential issue is the requirement for relatively high critical magnetic fields and field intervals (1.5-3 T) for the onset of FIPT and for reversible FIPT, respectively.

  12. Giant magnetocaloric effect and temperature induced magnetization jump in GdCrO{sub 3} single crystal

    SciTech Connect (OSTI)

    Yin, L. H.; Yang, J.; Kan, X. C.; Song, W. H.; Dai, J. M.; Sun, Y. P.

    2015-04-07

    We report on a systematic study of the single-crystal GdCrO{sub 3}, which shows various novel magnetic features, such as temperature-induced magnetization reversal (TMR), temperature-induced magnetization jump (TMJ), spin reorientation, and giant magnetocaloric effect (MCE). In the field-cooled cooling process with modest magnetic field along the c axis, GdCrO{sub 3} first shows a TMR at T{sub comp}∼120−130 K and then an abrupt TMJ with a sign change of magnetization at T{sub jump}∼52−120 K, and finally a spin reorientation at T{sub SR}∼4−7 K. Interestingly, the remarkable TMJ behavior, which was not reported ever before, persists at higher fields up to 10 kOe even when TMR disappears. In addition, giant MCE with the maximum value of magnetic entropy change reaching ∼31.6 J/kg K for a field change of 44 kOe was also observed in GdCrO{sub 3} single crystal, suggesting it could be a potential material for low-T magnetic refrigeration. A possible mechanism for these peculiar magnetic behaviors is discussed based on the various competing magnetic interactions between the 3d electrons of Cr{sup 3+} ions and 4f electrons of Gd{sup 3+} ions.

  13. Counter-Top Thermoacoustic Refrigerator- An Experimental Investigation

    SciTech Connect (OSTI)

    Anwar, Mahmood; Ghazali, Normah Mohd

    2010-06-28

    Thermoacoustic phenomenon is a new alternative refrigeration technology. Though design and fabrication is complex for getting the desired effect, it is environmentally friendly and successful system showed that it is relatively easy to run compared to the traditional vapor compression refrigeration system. Currently, theories supporting the thermoacoustic refrigeration systems are yet to be comprehensive to make them commercially viable. Theoretical, experimental, and numerical studies are being done to address the thermodynamics-acoustics interactions. In this study, experimental investigations were completed to test the feasibility of the practical use of a thermoacoustic refrigerator in its counter-top form for future specific application. The system was designed and fabricated based on linear acoustic theory. Acoustic power was given by a loud speaker and thermoacoustic effects were measured in terms of the cooling effects produced at resonanance. Investigations showed that discrepancies between designed and working resonance frequency exist. Thermoacoutic cooling improved at a certain frequency, achieved when the working frequency was varied away from the design frequency. A cooling effect of 4.8 K below the ambient temperature of 23.3 deg. C was obtained from the counter-top thermoacoustic system. This system uses no refrigerants and no compressor to generate the cooling effect, a potential to be further investigated for a practical system.

  14. Experimental Investigation of Magnetic, Superconducting, and other Phase Transitions in novel F-Electron Materials at Ultra-high Pressures - Final Progress Report

    SciTech Connect (OSTI)

    Maple, Brian; Jeffires, Jason

    2006-07-28

    This grant, entitled “Experimental investigation of magnetic, superconducting and other phase transitions in novel f-electron materials at ultrahigh pressures,” spanned the funding period from May 1st, 2003 until April 30th, 2006. The major goal of this grant was to develop and utilize an ultrahigh pressure facility—capable of achieving very low temperatures, high magnetic fields, and extreme pressures as well as providing electrical resistivity, ac susceptibility, and magnetization measurement capabilities under pressure—for the exploration of magnetic, electronic, and structural phases and any corresponding interactions between these states in novel f-electron materials. Realizing this goal required the acquisition, development, fabrication, and implementation of essential equipment, apparatuses, and techniques. The following sections of this report detail the establishment of an ultrahigh pressure facility (Section 1) and measurements performed during the funding period (Section 2), as well as summarize the research project (Section 3), project participants and their levels of support (Section 4), and publications and presentations (Section 5).

  15. Frost sensor for use in defrost controls for refrigeration

    DOE Patents [OSTI]

    French, Patrick D.; Butz, James R.; Veatch, Bradley D.; O'Connor, Michael W.

    2002-01-01

    An apparatus and method for measuring the total thermal resistance to heat flow from the air to the evaporative cooler fins of a refrigeration system. The apparatus is a frost sensor that measures the reduction in heat flow due to the added thermal resistance of ice (reduced conduction) as well as the reduction in heat flow due to the blockage of airflow (reduced convection) from excessive ice formation. The sensor triggers a defrost cycle when needed, instead of on a timed interval. The invention is also a method for control of frost in a system that transfers heat from air to a refrigerant along a thermal path. The method involves measuring the thermal conductivity of the thermal path from the air to the refrigerant, recognizing a reduction in thermal conductivity due to the thermal insulation effect of the frost and due to the loss of airflow from excessive ice formation; and controlling the defrosting of the system.

  16. Demand Response Opportunities in Industrial Refrigerated Warehouses in California

    SciTech Connect (OSTI)

    Goli, Sasank; McKane, Aimee; Olsen, Daniel

    2011-06-14

    Industrial refrigerated warehouses that implemented energy efficiency measures and have centralized control systems can be excellent candidates for Automated Demand Response (Auto-DR) due to equipment synergies, and receptivity of facility managers to strategies that control energy costs without disrupting facility operations. Auto-DR utilizes OpenADR protocol for continuous and open communication signals over internet, allowing facilities to automate their Demand Response (DR). Refrigerated warehouses were selected for research because: They have significant power demand especially during utility peak periods; most processes are not sensitive to short-term (2-4 hours) lower power and DR activities are often not disruptive to facility operations; the number of processes is limited and well understood; and past experience with some DR strategies successful in commercial buildings may apply to refrigerated warehouses. This paper presents an overview of the potential for load sheds and shifts from baseline electricity use in response to DR events, along with physical configurations and operating characteristics of refrigerated warehouses. Analysis of data from two case studies and nine facilities in Pacific Gas and Electric territory, confirmed the DR abilities inherent to refrigerated warehouses but showed significant variation across facilities. Further, while load from California's refrigerated warehouses in 2008 was 360 MW with estimated DR potential of 45-90 MW, actual achieved was much less due to low participation. Efforts to overcome barriers to increased participation may include, improved marketing and recruitment of potential DR sites, better alignment and emphasis on financial benefits of participation, and use of Auto-DR to increase consistency of participation.

  17. Development and Evaluation of a Sandia Cooler-based Refrigerator Condenser

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    | Department of Energy and Evaluation of a Sandia Cooler-based Refrigerator Condenser Development and Evaluation of a Sandia Cooler-based Refrigerator Condenser This report describes the first design of a refrigerator condenser using the Sandia Cooler, i.e. air-bearing supported rotating heat-sink impeller. The project included baseline performance testing of a residential refrigerator, analysis, and design development of a Sandia Cooler condenser assembly including a spiral channel

  18. DOE Publishes Notice of Proposed Rulemaking for Commercial Refrigeration Equipment Test Procedure

    Broader source: Energy.gov [DOE]

    The Department of Energy has published a notice of proposed rulemaking regarding test procedures for commercial refrigeration equipment.

  19. Synthesis and evaluation of ultra-pure rare-earth-coped glass for laser refrigeration

    SciTech Connect (OSTI)

    Patterson, Wendy M; Hehlen, Markus P; Epstein, Richard I; Sheik-bahae, Mansoor

    2009-01-01

    Significant progress has been made in synthesizing and characterizing ultra-pure, rare-earth doped ZIBLAN (ZrF{sub 4}-InF{sub 3}BaF{sub 2}-LaF{sub 3}-AlF{sub 3}-NaF) glass capable of laser refrigeration. The glass was produced from fluorides which were purified and subsequently treated with hydrofluoric gas at elevated temperatures to remove impurities before glass formation. Several Yb3 +-doped samples were studied with degrees of purity and composition with successive iterations producing an improved material. We have developed a non-invasive, spectroscopic technique, two band differential luminescence thermometry (TBDLT), to evaluate the intrinsic quality of the ytterbium doped ZIBLAN used for laser cooling experiments. TBDLT measures local temperature changes within an illuminated volume resulting solely from changes in the relative thermal population of the excited state levels. This TBDLT technique utilizes two commercially available band pass filters to select and integrate the 'difference regions' of interest in the luminescence spectra. The goal is to determine the minimum temperature to which the ytterbium sample can cool on the local scale, unphased by surface heating. This temperature where heating and cooling are exactly balanced is the zero crossing temperature (ZCT) and can be used as a measure for the presence of impurities and the overall quality of the laser cooling material. Overall, favorable results were obtained from 1 % Yb3+-doped glass, indicating our glasses are desirable for laser refrigeration.

  20. Simplified Helium Refrigerator Cycle Analysis Using the `Carnot Step'

    SciTech Connect (OSTI)

    P. Knudsen; V. Ganni

    2006-05-01

    An analysis of the Claude form of an idealized helium liquefier for the minimum input work reveals the ''Carnot Step'' for helium refrigerator cycles. As the ''Carnot Step'' for a multi-stage polytropic compression process consists of equal pressure ratio stages; similarly for an idealized helium liquefier the ''Carnot Step'' consists of equal temperature ratio stages for a given number of expansion stages. This paper presents the analytical basis and some useful equations for the preliminary examination of existing and new Claude helium refrigeration cycles.

  1. Proceedings of the 1993 non-fluorocarbon insulation, refrigeration and air conditioning technology workshop

    SciTech Connect (OSTI)

    Not Available

    1994-09-01

    Sessions included: HFC blown polyurethanes, carbon dioxide blown foam and extruded polystyrenes, plastic foam insulations, evacuated panel insulation, refrigeration and air conditioning, absorption and adsorption and stirling cycle refrigeration, innovative cooling technologies, and natural refrigerants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  2. 2014-07-10 Issuance: Test Procedures for Refrigerators, Refrigerator-Freezers, and Freezers; Final Rule Correction

    Broader source: Energy.gov [DOE]

    This document is a pre-publication Federal Register final rule correction regarding test procedures for refrigerators, refrigerator-freezers, and freezers, as issued by the Deputy Assistant Secretary for Energy Efficiency on July 10, 2014. Though it is not intended or expected, should any discrepancy occur between the document posted here and the document published in the Federal Register, the Federal Register publication controls. This document is being made available through the Internet solely as a means to facilitate the public's access to this document.

  3. Magnetic and magnetocaloric properties of bulk dysprosium chromite

    SciTech Connect (OSTI)

    McDannald, A.; Institute of Material Science, University of Connecticut, Storrs, Connecticut 06269 ; Kuna, L.; Jain, M.; Department of Physics, University of Connecticut, Storrs, Connecticut 06269

    2013-09-21

    In this work, a polycrystalline bulk DyCrO{sub 3} sample was prepared by a solution route and the structural and magnetic properties were investigated. The phase purity and ionic valence state of the DyCrO{sub 3} sample were determined by x-ray diffraction/Raman spectroscopy and x-ray photoelectron spectroscopy, respectively. The AC and DC magnetization measurements revealed the onset of antiferromagnetic order at 146 K with an effective moment of 8.88 μ{sub B}. Isothermal magnetization measurements of this material are presented for the first time, showing a peak in the coercive field at 80 K that is explained by the competition between the paramagnetic Dy{sup 3+} and Cr{sup 3+} sublattices. DyCrO{sub 3} was found to display a large magnetocaloric effect (8.4 J/kg K) and relative cooling power (217 J/kg) at 4 T applied field, which renders DyCrO{sub 3} useful for magnetic refrigeration between 5 K and 30 K.

  4. Purchasing Energy-Efficient Commercial Refrigerators and Freezers

    Broader source: Energy.gov [DOE]

    The Federal Energy Management Program (FEMP) provides acquisition guidance for commercial refrigerators and freezers, a product category covered by ENERGY STAR efficiency requirements. Federal laws and requirements mandate that agencies purchase ENERGY STAR-qualified products or FEMP-designated products in all product categories covered by these programs and in any acquisition actions that are not specifically exempted by law.

  5. Purchasing Energy-Efficient Refrigerated Beverage Vending Machines

    Broader source: Energy.gov [DOE]

    FEMP provides acquisition guidance and Federal efficiency requirements across a variety of product categories, including refrigerated beverage vending machines, which are covered by the ENERGY STAR® program. Federal laws and requirements mandate that agencies meet these efficiency requirements in all procurement and acquisition actions that are not specifically exempted by law.

  6. Superefficient Refrigerators: Opportunities and Challenges for Efficiency Improvement Globally

    SciTech Connect (OSTI)

    Shah, Nihar; Park, Won Young; Bojda, Nicholas; McNeil, Michael A.

    2014-08-01

    As an energy-intensive mainstream product, residential refrigerators present a significant opportunity to reduce electricity consumption through energy efficiency improvements. Refrigerators expend a considerable amount of electricity during normal use, typically consuming between 100 to 1,000 kWh of electricity per annum. This paper presents the results of a technical analysis done for refrigerators in support of the Super-efficient Equipment and Appliance Deployment (SEAD) initiative. Beginning from a base case representative of the average unit sold in India, we analyze efficiency improvement options and their corresponding costs to build a cost-versus-efficiency relationship. We then consider design improvement options that are known to be the most cost effective and that can improve efficiency given current design configurations. We also analyze and present additional super-efficient options, such as vacuum-insulated panels. We estimate the cost of conserved electricity for the various options, allowing flexible program design for market transformation programs toward higher efficiency. We estimate ~;;160TWh/year of energy savings are cost effective in 2030, indicating significant potential for efficiency improvement in refrigerators in SEAD economies and China.

  7. Triple loop heat exchanger for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C.

    1984-01-01

    A triple loop heat exchanger for an absorption refrigeration system is disclosed. The triple loop heat exchanger comprises portions of a strong solution line for conducting relatively hot, strong solution from a generator to a solution heat exchanger of the absorption refrigeration system, conduit means for conducting relatively cool, weak solution from the solution heat exchanger to the generator, and a bypass system for conducting strong solution from the generator around the strong solution line and around the solution heat exchanger to an absorber of the refrigeration system when strong solution builds up in the generator to an undesirable level. The strong solution line and the conduit means are in heat exchange relationship with each other in the triple loop heat exchanger so that, during normal operation of the refrigeration system, heat is exchanged between the relatively hot, strong solution flowing through the strong solution line and the relatively cool, weak solution flowing through the conduit means. Also, the strong solution line and the bypass system are in heat exchange relationship in the triple loop heat exchanger so that if the normal flow path of relatively hot, strong solution flowing from the generator to an absorber is blocked, then this relatively, hot strong solution which will then be flowing through the bypass system in the triple loop heat exchanger, is brought into heat exchange relationship with any strong solution which may have solidified in the strong solution line in the triple loop heat exchanger to thereby aid in desolidifying any such solidified strong solution.

  8. High-Efficiency, Low-Emission Refrigeration System | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficiency, Low-Emission Refrigeration System High-Efficiency, Low-Emission Refrigeration System Image of the compressor rack and system diagram for the CO2 refrigeration system.<br /> Credit: Oak Ridge National Lab Image of the compressor rack and system diagram for the CO2 refrigeration system. Credit: Oak Ridge National Lab Diagram of the compressor rack and system diagram for the CO2 refrigeration system.<br /> Credit: Oak Ridge National Lab Diagram of the compressor rack and

  9. Critical Materials:

    Energy Savers [EERE]

    Facilities » Critical Materials Hub Critical Materials Hub Green light reflection from a low-oxygen environment 3D printer laser deposition of metal powder alloys. Photo courtesy of The Critical Materials Institute, Ames Laboratory Green light reflection from a low-oxygen environment 3D printer laser deposition of metal powder alloys. Photo courtesy of The Critical Materials Institute, Ames Laboratory Critical materials, including some rare earth elements that possess unique magnetic,

  10. Floating Refrigerant Loop Based on R-134a Refrigerant Cooling of High-Heat Flux Electronics

    SciTech Connect (OSTI)

    Lowe, K.T.

    2005-10-07

    The Oak Ridge National Laboratory (ORNL) Power Electronics and Electric Machinery Research Center (PEEMRC) have been developing technologies to address the thermal issues associated with hybrid vehicles. Removal of the heat generated from electrical losses in traction motors and their associated power electronics is essential for the reliable operation of motors and power electronics. As part of a larger thermal control project, which includes shrinking inverter size and direct cooling of electronics, ORNL has developed U.S. Patent No. 6,772,603 B2, ''Methods and Apparatus for Thermal Management of Vehicle Systems and Components'' [1], and patent pending, ''Floating Loop System for Cooling Integrated Motors and Inverters Using Hot Liquid Refrigerant'' [2]. The floating-loop system provides a large coefficient of performance (COP) for hybrid-drive component cooling. This loop (based on R-134a) is integrated with a vehicle's existing air-conditioning (AC) condenser, which dissipates waste heat to the ambient air. Because the temperature requirements for cooling of power electronics and electric machines are not as low as that required for passenger compartment air, this adjoining loop can operate on the high-pressure side of the existing AC system. This arrangement also allows the floating loop to run without the need for the compressor and only needs a small pump to move the liquid refrigerant. For the design to be viable, the loop must not adversely affect the existing system. The loop should also provide a high COP, a flat-temperature profile, and low-pressure drop. To date, the floating-loop test prototype has successfully removed 2 kW of heat load in a 9 kW automobile passenger AC system with and without the automotive AC system running. The COP for the tested floating-loop system ranges from 40-45, as compared to a typical AC system COP of about 2-4. The estimated required waste-heat load for future hybrid applications is 5.5 kW and the existing system could be easily scaleable for this larger load.

  11. ISSUANCE 2015-07-15: Energy Conservation Program: Test Procedure for Refrigerated Bottled or Canned Beverage Vending Machines, Final Rule

    Broader source: Energy.gov [DOE]

    Energy Conservation Program: Test Procedure for Refrigerated Bottled or Canned Beverage Vending Machines, Final Rule

  12. Mesoporous Co{sub 3}O{sub 4} nanostructured material synthesized by one-step soft-templating: A magnetic study

    SciTech Connect (OSTI)

    Poyraz, Altug S.; Kuo, Chung-Hao; Li, Nan; Hines, William A. Perry, David M.; Suib, Steven L.

    2014-03-21

    A combined magnetization and zero-field {sup 59}Co spin-echo nuclear magnetic resonance (NMR) study has been carried out on one member of a recently developed class of highly ordered mesoporous nanostructured materials, mesoporous Co{sub 3}O{sub 4} (designated UCT-8, University of Connecticut, mesoporous materials). The material was synthesized using one-step soft-templating by an inverse micelles packing approach. Characterization of UCT-8 by powder x-ray diffraction and electron microscopy reveals that the mesostructure consists of random close-packed Co{sub 3}O{sub 4} nanoparticles ??12?nm in diameter. The N{sub 2} sorption isotherm for UCT-8, which is type IV with a type H1 hysteresis loop, yields a 134 m{sup 2}/g BET surface area and a 7.7?nm BJH desorption pore diameter. The effect of heat treatment on the structure is discussed. The antiferromagnetic Co{sub 3}O{sub 4} nanoparticles have a Nel temperature T{sub N}?=?27?K, somewhat lower than the bulk. A fit to the Curie-Weiss law over the temperature range 75?K???T???300?K yields an effective magnetic moment of ?{sub eff}?=?4.36??{sub B} for the Co{sup 2+} ions, indicative of some orbital contribution, and a Curie-Weiss temperature ??=??93.5?K, consistent with antiferromagnetic ordering. The inter-sublattice and intra-sublattice exchange constants for the Co{sup 2+} ions are J{sub 1}/k{sub B}?=?(?)4.75?K and J{sub 2}/k{sub B}?=?(?)0.87?K, respectively, both corresponding to antiferromagnetic coupling. The presence of uncompensated surface spins is observed below T{sub N} with shifts in the hysteresis loops, i.e., an exchange-bias effect. The {sup 59}Co NMR spectrum for UCT-8, which is attributed to Co{sup 2+} ions at the tetrahedral A sites, is asymmetrically broadened with a peak at ?55?MHz (T?=?4.2?K). Since there is cubic symmetry at the A-sites, the broadening is indicative of a magnetic field distribution due to the uncompensated surface spins. The spectrum is consistent with antiferromagnetically ordered particles that are nanometer in size and single domain.

  13. Facility for low-temperature spin-polarized-scanning tunneling microscopy studies of magnetic/spintronic materials prepared in situ by nitride molecular beam epitaxy

    SciTech Connect (OSTI)

    Lin, Wenzhi; Foley, Andrew; Alam, Khan; Wang, Kangkang; Liu, Yinghao; Chen, Tianjiao; Pak, Jeongihm; Smith, Arthur R.

    2014-04-15

    Based on the interest in, as well as exciting outlook for, nitride semiconductor based structures with regard to electronic, optoelectronic, and spintronic applications, it is compelling to investigate these systems using the powerful technique of spin-polarized scanning tunneling microscopy (STM), a technique capable of achieving magnetic resolution down to the atomic scale. However, the delicate surfaces of these materials are easily corrupted by in-air transfers, making it unfeasible to study them in stand-alone ultra-high vacuum STM facilities. Therefore, we have carried out the development of a hybrid system including a nitrogen plasma assisted molecular beam epitaxy/pulsed laser epitaxy facility for sample growth combined with a low-temperature, spin-polarized scanning tunneling microscope system. The custom-designed molecular beam epitaxy growth system supports up to eight sources, including up to seven effusion cells plus a radio frequency nitrogen plasma source, for epitaxially growing a variety of materials, such as nitride semiconductors, magnetic materials, and their hetero-structures, and also incorporating in situ reflection high energy electron diffraction. The growth system also enables integration of pulsed laser epitaxy. The STM unit has a modular design, consisting of an upper body and a lower body. The upper body contains the coarse approach mechanism and the scanner unit, while the lower body accepts molecular beam epitaxy grown samples using compression springs and sample skis. The design of the system employs two stages of vibration isolation as well as a layer of acoustic noise isolation in order to reduce noise during STM measurements. This isolation allows the system to effectively acquire STM data in a typical lab space, which during its construction had no special and highly costly elements included, (such as isolated slabs) which would lower the environmental noise. The design further enables tip exchange and tip coating without breaking vacuum, and convenient visual access to the sample and tip inside a superconducting magnet cryostat. A sample/tip handling system is optimized for both the molecular beam epitaxy growth system and the scanning tunneling microscope system. The sample/tip handing system enables in situ STM studies on epitaxially grown samples, and tip exchange in the superconducting magnet cryostat. The hybrid molecular beam epitaxy and low temperature scanning tunneling microscopy system is capable of growing semiconductor-based hetero-structures with controlled accuracy down to a single atomic-layer and imaging them down to atomic resolution.

  14. Circulating heat exchangers for oscillating wave engines and refrigerators

    DOE Patents [OSTI]

    Swift, Gregory W.; Backhaus, Scott N.

    2003-10-28

    An oscillating-wave engine or refrigerator having a regenerator or a stack in which oscillating flow of a working gas occurs in a direction defined by an axis of a trunk of the engine or refrigerator, incorporates an improved heat exchanger. First and second connections branch from the trunk at locations along the axis in selected proximity to one end of the regenerator or stack, where the trunk extends in two directions from the locations of the connections. A circulating heat exchanger loop is connected to the first and second connections. At least one fluidic diode within the circulating heat exchanger loop produces a superimposed steady flow component and oscillating flow component of the working gas within the circulating heat exchanger loop. A local process fluid is in thermal contact with an outside portion of the circulating heat exchanger loop.

  15. Heat powered refrigeration compressor. Semi-annual technical report

    SciTech Connect (OSTI)

    Goad, R.R.

    1981-01-01

    The objective of this program is to develop and improve the design of previously started prototypes of the Heat Powered Refrigeration Compressor. To build this prototype and ready it for testing by the University of Evansville is another goal. This prototype will be of similar capacity as the compressor that will eventually be commercially produced. This unit can operate on almost any moderate temperature water heat source. This heat source could include such applications as industrial waste heat, solar, wood burning stove, resistance electrical heat produced by a windmill, or even perhaps heat put out by the condenser of another refrigeration system. Work performed in the past four months has consisted of: engineering of HX-1; comparisons of specifications from different companies to ensure state of the art applications of parts for project; coordinating project requirements with machine shop; designing condenser; and partial assembly of HX-1.

  16. Free displacer and Ringbom displacer for a Malone refrigerator

    SciTech Connect (OSTI)

    Swift, G.W.; Brown, A.O.

    1994-05-01

    Malone refrigeration uses a liquid near its critical point (instead of the customary gas) as the working fluid in a Stirling, Brayton, or similar regenerative or recuperative cycle. Thus far, we have focused on the Stirling cycle, to avoid the difficult construction of the high-pressure-difference counterflow recuperator required for a Brayton machine. Our first Malone refrigerator used liquid propylene (C{sub 3}H{sub 6}) in a double-acting 4-cylinder Stirling configuration. First measurements with a free displacer used in a liquid working fluid are presented. The displacer was operated both in harmonic mode and in Ringbom mode, in liquid carbon dioxide. The results are in reasonable agreement with expectations.

  17. PROCESS STUDY OF NOMINAL 2 K REFRIGERATION RECOVERY

    SciTech Connect (OSTI)

    Knudsen, Peter; Ganni, Venkatarao

    2008-03-01

    There is an increased interest in the nominal 2-K helium refrigeration systems (below lambda) for various test stands and applications at the present time. This paper presents the process parameter choices and their influence on the system performance of various noncold compressor configurations. This study is intended to facilitate the adoption of this process in conjunction with commercially-available small 4.5-K helium liquefaction systems. By way of an introduction, the efficiency of some commonly employed (but inefficient) 2-K process configurations are analyzed. Then the analyses of three nominal 2-K refrigeration-recovery process configurations are presented. The effect of the process parameters, such as flow imbalance, heat-exchanger size, supply pressure and 4.5-K plant interaction location(s) are investigated so that the optimum conditions yielding the required performance can be determined.

  18. Solar heat pump systems with refrigerant-filled collectors

    SciTech Connect (OSTI)

    O'Dell, M.P.; Beckman, W.A.; Mitchell, J.W.

    1983-01-01

    The heat pump system with a refrigerant-filled evaporator consists of a standard air-to-air or air-to-liquid heat pump that utilizes a solar panel as the evaporator. A combination of solar energy and convection heat transfer acts as the ''free'' energy absorbed by the collector/evaporator. In this paper, the seasonal performance of such systems for industrial applications will be presented. Performance of collector/evaporator heat pumps will be compared with alternative heat pump and solar systems. The benefits of covered and coverless collector/evaporators will be discussed. Results to date have shown that refrigerant-filled collector heat pumps do not perform as well as conventional heat pumps at small collector areas but have as much as 15% performance improvement over conventional heat pumps at an appropriate collector area.

  19. Pilot Testing of Commercial Refrigeration-Based Demand Response

    SciTech Connect (OSTI)

    Hirsch, Adam; Clark, Jordan; Deru, Michael; Trenbath, Kim; Doebber, Ian; Studer, Daniel

    2015-10-08

    Supermarkets potentially offer a substantial demand response (DR) resource because of their high energy intensity and use patterns. This report describes a pilot project conducted to better estimate supermarket DR potential. Previous work has analyzed supermarket DR using heating, ventilating, and air conditioning (HVAC), lighting, and anti-condensate heaters. This project was concerned with evaluating DR using the refrigeration system and quantifying the DR potential inherent in supermarket refrigeration systems. Ancillary aims of the project were to identify practical barriers to the implementation of DR programs in supermarkets and to determine which high-level control strategies were most appropriate for achieving certain DR objectives. The scope of this project does not include detailed control strategy development for DR or development of a strategy for regional implementation of DR in supermarkets.

  20. Magnetic nanohole superlattices

    DOE Patents [OSTI]

    Liu, Feng

    2013-05-14

    A magnetic material is disclosed including a two-dimensional array of carbon atoms and a two-dimensional array of nanoholes patterned in the two-dimensional array of carbon atoms. The magnetic material has long-range magnetic ordering at a temperature below a critical temperature Tc.

  1. Magnetically attached sputter targets

    DOE Patents [OSTI]

    Makowiecki, D.M.; McKernan, M.A.

    1994-02-15

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

  2. Waste heat driven absorption refrigeration process and system

    DOE Patents [OSTI]

    Wilkinson, William H.

    1982-01-01

    Absorption cycle refrigeration processes and systems are provided which are driven by the sensible waste heat available from industrial processes and other sources. Systems are disclosed which provide a chilled water output which can be used for comfort conditioning or the like which utilize heat from sensible waste heat sources at temperatures of less than 170.degree. F. Countercurrent flow equipment is also provided to increase the efficiency of the systems and increase the utilization of available heat.

  3. Fuel Cell Based Auxiliary Power Unit for Refrigerated Trucks

    SciTech Connect (OSTI)

    Brooks, Kriston P.

    2014-09-02

    This is the annual report for the Market Transformation project as required by DOE EERE's Fuel Cell Technologies Office. We have been provided with a specific format. It describes the work that was done in developing fuel-cell powered Transport Refrigeration Units for Reefer Trucks. It describes the progress that has been made by Nuvera and Plug Power as they develop and ultimately demonstrate this technology in real world application.

  4. New waste-heat refrigeration unit cuts flaring, reduces pollution

    SciTech Connect (OSTI)

    Brant, B.; Brueske, S.; Erickson, D.; Papar, R.

    1998-05-18

    Planetec Utility Services Co. Inc. and Energy Concepts Co. (ECC), with the help of the US Department of Energy (DOE), developed and commissioned a unique waste-heat powered LPG recovery plant in August 1997 at the 30,000 b/d Denver refinery, operated by Ultramar Diamond Shamrock (UDS). This new environmentally friendly technology reduces flare emissions and the loss of salable liquid-petroleum products to the fuel-gas system. The waste heat ammonia absorption refrigeration plant (Whaarp) is the first technology of its kind to use low-temperature waste heat (295 F) to achieve sub-zero refrigeration temperatures ({minus}40 F) with the capability of dual temperature loads in a refinery setting. The ammonia absorption refrigeration is applied to the refinery`s fuel-gas makeup streams to condense over 180 b/d of salable liquid hydrocarbon products. The recovered liquid, about 64,000 bbl/year of LPG and gasoline, increases annual refinery profits by nearly $1 million, while substantially reducing air pollution emissions from the refinery`s flare.

  5. Comparison of the order of magnetic phase transitions in several magnetocaloric materials using the rescaled universal curve, Banerjee and mean field theory criteria

    SciTech Connect (OSTI)

    Burrola-Gándara, L. A. Santillan-Rodriguez, C. R.; Rivera-Gomez, F. J.; Saenz-Hernandez, R. J.; Botello-Zubiate, M. E.; Matutes-Aquino, J. A.

    2015-05-07

    Magnetocaloric materials with second order phase transition near the Curie temperature can be described by critical phenomena theory. In this theory, scaling, universality, and renormalization are key concepts from which several phase transition order criteria are derived. In this work, the rescaled universal curve, Banerjee and mean field theory criteria were used to make a comparison for several magnetocaloric materials including pure Gd, SmCo{sub 1.8}Fe{sub 0.2}, MnFeP{sub 0.46}As{sub 0.54}, and La{sub 0.7}Ca{sub 0.15}Sr{sub 0.15}MnO{sub 3}. Pure Gd, SmCo{sub 1.8}Fe{sub 0.2}, and La{sub 0.7}Ca{sub 0.15}Sr{sub 0.15}MnO{sub 3} present a collapse of the rescaled magnetic entropy change curves into a universal curve, which indicates a second order phase transition; applying Banerjee criterion to H/σ vs σ{sup 2} Arrot plots and the mean field theory relation |ΔS{sub M}| ∝ (μ{sub 0}H/T{sub c}){sup 2/3} for the same materials also determines a second order phase transition. However, in the MnFeP{sub 0.46}As{sub 0.54} sample, the Banerjee criterion applied to the H/σ vs σ{sup 2} Arrot plot indicates a first order magnetic phase transition, while the mean field theory prediction for a second order phase transition, |ΔS{sub M}| ∝ (μ{sub 0}H/T{sub c}){sup 2/3}, describes a second order behavior. Also, a mixture of first and second order behavior was indicated by the rescaled universal curve criterion. The diverse results obtained for each criterion in MnFeP{sub 0.46}As{sub 0.54} are apparently related to the magnetoelastic effect and to the simultaneous presence of weak and strong magnetism in Fe (3f) and Mn (3g) alternate atomic layers, respectively. The simultaneous application of the universal curve, the Banerjee and the mean field theory criteria has allowed a better understanding about the nature of the order of the phase transitions in different magnetocaloric materials.

  6. Potential of the tractor-trailer and container segments as entry markets for a proposed refrigeration technology

    SciTech Connect (OSTI)

    Smith, S.A.; Davis, L.J.; Garrett, B.A.

    1987-05-01

    The refrigerated trailer and container segments of the transportation industry are evaluated as potential entry markets for a proposed absorption refrigeration technology. To perform this analysis the existing transportation refrigeration industry is characterized; this includes a description of the current refrigeration technology, rating systems, equipment manufacturers, maintenance requirements, and sales trends. This information indicates that the current transportation refrigeration industry is composed of two major competitors, Thermo King and Carrier. In addition, it has low profit potential, some barriers to entry and low growth potential. Data are also presented that characterize the transportation refrigeration consumers, specifically, major groups, market segmentation, consumer decision process, and buying criteria. This consumer information indicates that the majority of refrigerated trailer consumers are private carriers, and that the majority of refrigerated container consumers are shipping companies. Also, these consumers are primarily interested in buying reliable equipment at a low price, and are quite satisfied with existing refrigeration equipment.

  7. The LSST Camera 500 watt -130 degC Mixed Refrigerant Cooling System

    SciTech Connect (OSTI)

    Bowden, Gordon B.; Langton, Brian J.; Little, William A.; Powers, Jacob R; Schindler, Rafe H.; Spektor, Sam; /MMR-Technologies, Mountain View, CA

    2014-05-28

    The LSST Camera has a higher cryogenic heat load than previous CCD telescope cameras due to its large size (634 mm diameter focal plane, 3.2 Giga pixels) and its close coupled front-end electronics operating at low temperature inside the cryostat. Various refrigeration technologies are considered for this telescope/camera environment. MMR-Technology’s Mixed Refrigerant technology was chosen. A collaboration with that company was started in 2009. The system, based on a cluster of Joule-Thomson refrigerators running a special blend of mixed refrigerants is described. Both the advantages and problems of applying this technology to telescope camera refrigeration are discussed. Test results from a prototype refrigerator running in a realistic telescope configuration are reported. Current and future stages of the development program are described. (auth)

  8. Method of removing an immiscible lubricant from a refrigeration system and apparatus for same

    DOE Patents [OSTI]

    Spauschus, H.O.; Starr, T.L.

    1999-03-30

    A method is described for separating an immiscible lubricant from a liquid refrigerant in a refrigerating system including a compressor, a condenser, an expansion device and an evaporator, wherein the expansion device is connected to the condenser by a liquid refrigerant flow line for liquid refrigerant and immiscible lubricant. The method comprising slowing the rate of flow of the liquid refrigerant and immiscible lubricant between the condenser and the expansion device such that the liquid refrigerant and the immiscible lubricant separate based upon differences in density. The method also comprises collecting the separated immiscible lubricant in a collection chamber in fluid communication with the separated immiscible lubricant. Apparatus for performing the method is also disclosed. 3 figs.

  9. Liquid over-feeding refrigeration system and method with integrated accumulator-expander-heat exchanger

    DOE Patents [OSTI]

    Mei, V.C.; Chen, F.C.

    1997-04-22

    A refrigeration system is described having a vapor compression cycle utilizing a liquid over-feeding operation with an integrated accumulator-expander-heat exchanger. Hot, high-pressure liquid refrigerant from the condenser passes through one or more lengths of capillary tubing substantially immersed in a pool liquid refrigerant in the accumulator-expander-heat exchanger for simultaneously sub-cooling and expanding the liquid refrigerant while vaporizing liquid refrigerant from the pool for the return thereof to the compressor as saturated vapor. The sub-cooling of the expanded liquid provides for the flow of liquid refrigerant into the evaporator for liquid over-feeding the evaporator and thereby increasing the efficiency of the evaporation cycle. 4 figs.

  10. Liquid over-feeding refrigeration system and method with integrated accumulator-expander-heat exchanger

    DOE Patents [OSTI]

    Mei, Viung C.; Chen, Fang C.

    1997-01-01

    A refrigeration system having a vapor compression cycle utilizing a liquid over-feeding operation with an integrated accumulator-expander-heat exchanger. Hot, high-pressure liquid refrigerant from the condenser passes through one or more lengths of capillary tubing substantially immersed in a pool liquid refrigerant in the accumulator-expander-heat exchanger for simultaneously sub-cooling and expanding the liquid refrigerant while vaporizing liquid refrigerant from the pool for the return thereof to the compressor as saturated vapor. The sub-cooling of the expanded liquid provides for the flow of liquid refrigerant into the evaporator for liquid over-feeding the evaporator and thereby increasing the efficiency of the evaporation cycle.

  11. Calculations of the magnetic entropy change in amorphous through a microscopic anisotropic model: Applications to Dy{sub 70}Zr{sub 30} and DyCo{sub 3.4} alloys

    SciTech Connect (OSTI)

    Ranke, P. J. von Nóbrega, E. P.; Ribeiro, P. O.; Alvarenga, T. S. T.; Lopes, P. H. O.; Sousa, V. S. R. de; Oliveira, N. A. de; Caldas, A.; Alho, B. P.; Carvalho, G.; Magnus, A.

    2014-10-14

    We report theoretical investigations on the magnetocaloric effect, described by the magnetic entropy change in rare earth—transition metal amorphous systems. The model includes the local anisotropy on the rare earth ions in Harris-Plischke-Zuckermann assumptions. The transition metals ions are treated in terms of itinerant electron ferromagnetism and the magnetic moment of rare earth ions is coupled to the polarized d-band by a local exchange interaction. The magnetocaloric effect was calculated in DyCo{sub 3.4} system, which presents amorphous sperimagnetic configuration. The calculations predict higher refrigerant capacity in the amorphous DyCo{sub 3.4} than in DyCo{sub 2} crystal, highlighting the importance of amorphous magnetocaloric materials. Our calculation of the magnetocaloric effect in Dy{sub 70}Zr{sub 30}, which presents amorphous asperomagnetic configuration, is in good agreement with the experimental result. Furthermore, magnetic entropy changes associated with crystal-amorphous configurations change are estimated.

  12. The superfluid Stirling refrigerator, a new method for cooling below 0.5 K

    SciTech Connect (OSTI)

    Brisson, J.G.; Kotsubo, V.; Swift, G.W.

    1993-04-09

    A new subkelvin refrigerator, the superfluid Stirling cycle refrigerator, uses a working fluid of {sup 3}He-{sup 4}He mixture in a Stirling cycle. The thermodynamically active components of the mixture are the {sup 3}He, which behaves like a Boltzman gas, and the phonon-roton gas in the {sup 4}He. The superfluid component of the liquid is inert. Two refrigerators have been built and temperatures of 340 mK have been achieved.

  13. The superfluid Stirling refrigerator, a new method for cooling below 0. 5 K

    SciTech Connect (OSTI)

    Brisson, J.G.; Kotsubo, V.; Swift, G.W.

    1993-04-09

    A new subkelvin refrigerator, the superfluid Stirling cycle refrigerator, uses a working fluid of [sup 3]He-[sup 4]He mixture in a Stirling cycle. The thermodynamically active components of the mixture are the [sup 3]He, which behaves like a Boltzman gas, and the phonon-roton gas in the [sup 4]He. The superfluid component of the liquid is inert. Two refrigerators have been built and temperatures of 340 mK have been achieved.

  14. Walk-in Cooler/Walk-in Freezer Refrigeration Systems - Enforcement Policy |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Walk-in Cooler/Walk-in Freezer Refrigeration Systems - Enforcement Policy Walk-in Cooler/Walk-in Freezer Refrigeration Systems - Enforcement Policy February 1, 2016 DOE will not seek civil penalties or injunctive relief concerning violations of certain energy conservation standards applicable to refrigeration systems of walk-in coolers/walk-in freezers. PDF icon Enforcement Policy - WICF (02/01/2016) PDF icon Enforcement Policy - WICF (8/31/2015 - OBSOLETE) PDF icon

  15. Development of Versatile Compressor Modeling using Approximation Techniques for Alternative Refrigerants Evaluation

    SciTech Connect (OSTI)

    Abdelaziz, Omar; Shrestha, Som S

    2014-01-01

    Refrigerants are the life-blood of vapor compression systems that are widely used in Heating, Ventilation, Air-Conditioning, and Refrigeration (HVAC&R) applications. The HVAC&R community is currently transitioning from main-stream refrigerants that have high Global Warming Potential (GWP) to alternative lower-GWP refrigerants. During this transition, it is important to account for the life cycle climate performance of alternative refrigerants since their performance will be different than that of higher-GWP refrigerants. This requires the evaluation of the system performance with the new refrigerants. Unfortunately, it is extremely difficult to predict the realistic performance of new alternative refrigerants without experimental validation. One of the main challenges in this regard is modeling the compressor performance with high fidelity due to the complex interaction of operating parameters, geometry, boundary conditions, and fluid properties. High fidelity compressor models are computationally expensive and require significant pre-processing to evaluate the performance of alternative refrigerants. This paper presents a new approach to modeling compressor performance when alternative refrigerants are used. The new modeling concept relies on using existing compressor performance to create an approximate model that captures the dependence of compressor performance on key operating parameters and fluid properties. The model can be built using a myriad of approximation techniques. This paper focuses on Kriging-based techniques to develop higher fidelity approximate compressor models. Baseline and at least one alternative refrigerant performance data are used to build the model. The model accuracy was evaluated by comparing the model results with compressor performance data using other refrigerants. Preliminary results show that the approximate model can predict the compressor mass flow rate and power consumption within 5%.

  16. A Variable Refrigerant Flow Heat Pump Computer Model in EnergyPlus

    SciTech Connect (OSTI)

    Raustad, Richard A.

    2013-01-01

    This paper provides an overview of the variable refrigerant flow heat pump computer model included with the Department of Energy's EnergyPlusTM whole-building energy simulation software. The mathematical model for a variable refrigerant flow heat pump operating in cooling or heating mode, and a detailed model for the variable refrigerant flow direct-expansion (DX) cooling coil are described in detail.

  17. Elastohydrodynamic Lubrication with Polyolester Lubricants and HFC Refrigerants, Final Report, Volume 2

    SciTech Connect (OSTI)

    Gunsel, Selda; Pozebanchuk, Michael

    1999-04-01

    Lubrication properties of refrigeration lubricants were investigated in high pressure nonconforming contacts under different conditions of temperature, rolling speed, and refrigerant concentration. The program was based upon the recognition that the lubrication regime in refrigeration compressors is generally elastohydrodynamic or hydrodynamic, as determined by the operating conditions of the compressor and the properties of the lubricant. Depending on the compressor design, elastohydrodynamic lubrication conditions exist in many rolling and sliding elements of refrigeration compressors such as roller element bearings, gears, and rotors. The formation of an elastohydrodynamic film separating rubbing surfaces is important in preventing the wear and failure of compressor elements. It is, therefore, important to predict the elastohydrodynamic (EHD) performance of lubricants under realistic tribocontact renditions. This is, however, difficult as the lubricant properties that control film formation are critically dependent upon pressure and shear, and cannot be evaluated using conventional laboratory instruments. In this study, the elastohydrodynamic behavior of refrigeration lubricants with and without the presence of refrigerants was investigated using the ultrathin film EHD interferometry technique. This technique enables very thin films, down to less than 5 nm, to be measured accurately within an EHD contact under realistic conditions of temperature, shear, and pressure. The technique was adapted to the study of lubricant refrigerant mixtures. Film thickness measurements were obtained on refrigeration lubricants as a function of speed, temperature, and refrigerant concentration. The effects of lubricant viscosity, temperature, rolling speed, and refrigerant concentration on EHD film formation were investigated. From the film thickness measurements, effective pressure-viscosity coefficients were calculated. The lubricants studied in this project included two naphthenic mineral oils (NMO), four polyolesters (POE), and two polyvinyl ether (PVE) fluids. These fluids represented viscosity grades of ISO 32 and ISO 68 and are shown in a table. Refrigerants studied included R-22, R-134a, and R-410A. Film thickness measurements were conducted at 23 C, 45 C, and 65 C with refrigerant concentrations ranging from zero to 60% by weight.

  18. 2015-03-26: Miscellaneous Refrigeration Products; Notice of Intent to

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Establish an ASRAC Working Group | Department of Energy : Miscellaneous Refrigeration Products; Notice of Intent to Establish an ASRAC Working Group 2015-03-26: Miscellaneous Refrigeration Products; Notice of Intent to Establish an ASRAC Working Group This document is a pre-publication Federal Register Notice of Intent regarding establishment of an ASRAC Working Group for Miscellaneous Refrigeration Products, as issued by the Deputy Assistant Secretary for Energy Efficiency on March 26,

  19. Origin of the positive spin-12 photoluminescence-detected magnetic resonance in π-conjugated materials and devices

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chen, Ying; Cai, Min; Hellerich, Emily; Shinar, Ruth; Shinar, Joseph

    2015-09-02

    The spin-1/2 single-modulation (SM) and double-modulation (DM) photoluminescence (PL) detected magnetic resonance (PLDMR) in poly(2-methoxy-5-(2'-ethyl)–hexoxy-1,4- phenylene vinylene) (MEH-PPV) films and poly(3-hexylthiophene) (P3HT) films is described, analyzed, and discussed. In particular, the models based on spin-dependent recombination of charge pairs (SDR) and triplet-polaron quenching (TPQ) are evaluated. By analyzing the dependence of the resonance amplitude on the microwave chopping (modulation) frequency using rate equations, it is demonstrated that the TPQ model can well explain the observed resonance behavior, while SDR model cannot reproduce the results of the observed DM-PLDMR. As a result, the observed spin-1/2 PLDMR is assigned to TPQ rathermore » than SDR, even though the latter may also be present.« less

  20. Research and Development Roadmap For Next-Generation Low-Global Warming Potential Refrigerants

    SciTech Connect (OSTI)

    none,

    2011-07-01

    The Department of Energy commissioned this roadmap to establish a set of high-priority research and development (R&D) activities that will accelerate the transition to low-GWP refrigerants across the entire heating, ventilation, air-conditioning and refrigeration (HVAC&R) industry. The schedule of R&D activities occurs within an accelerated five-year timeframe, and covers several prominent equipment types. The roadmap is organized around four primary objectives to: assess and mitigate safety risks, characterize refrigerant properties, understand efficiency and environmental tradeoffs, and support new refrigerant and equipment development.

  1. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Cool Magnetic Molecules Print Wednesday, 25 May 2011 00:00 Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost

  2. QM Power Inc: Commercial Refrigeration Fan Applications | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The Q-Sync technology uses a permanent magnet synchronous motor topology and a simple, ... More Documents & Publications Advanced permanent magnet motor technology will drive HVAC ...

  3. Refrigeration system with a compressor-pump unit and a liquid-injection desuperheating line

    DOE Patents [OSTI]

    Gaul, Christopher J.

    2001-01-01

    The refrigeration system includes a compressor-pump unit and/or a liquid-injection assembly. The refrigeration system is a vapor-compression refrigeration system that includes an expansion device, an evaporator, a compressor, a condenser, and a liquid pump between the condenser and the expansion device. The liquid pump improves efficiency of the refrigeration system by increasing the pressure of, thus subcooling, the liquid refrigerant delivered from the condenser to the expansion device. The liquid pump and the compressor are driven by a single driving device and, in this regard, are coupled to a single shaft of a driving device, such as a belt-drive, an engine, or an electric motor. While the driving device may be separately contained, in a preferred embodiment, the liquid pump, the compressor, and the driving device (i.e., an electric motor) are contained within a single sealable housing having pump and driving device cooling paths to subcool liquid refrigerant discharged from the liquid pump and to control the operating temperature of the driving device. In another aspect of the present invention, a liquid injection assembly is included in a refrigeration system to divert liquid refrigerant from the discharge of a liquid pressure amplification pump to a compressor discharge pathway within a compressor housing to desuperheat refrigerant vapor to the saturation point within the compressor housing. The liquid injection assembly includes a liquid injection pipe with a control valve to meter the volume of diverted liquid refrigerant. The liquid injection assembly may also include a feedback controller with a microprocessor responsive to a pressure sensor and a temperature sensor both positioned between the compressor to operate the control valve to maintain the refrigerant at or near saturation.

  4. Superconducting magnetic Wollaston prism for neutron spin encoding

    SciTech Connect (OSTI)

    Li, F., E-mail: fankli@indiana.edu; Parnell, S. R.; Wang, T.; Baxter, D. V. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States)] [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Hamilton, W. A. [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)] [Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States); Maranville, B. B. [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)] [National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States); Semerad, R. [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany)] [Ceraco Ceramic Coating GmbH, Ismaning 85737 (Germany); Cremer, J. T. [Adelphi Technology Inc., Redwood City, California 94063 (United States)] [Adelphi Technology Inc., Redwood City, California 94063 (United States); Pynn, R. [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States) [Center for Exploration of Energy and Matter, Indiana University, Bloomington, Indiana 47408 (United States); Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830 (United States)

    2014-05-15

    A magnetic Wollaston prism can spatially split a polarized neutron beam into two beams with different neutron spin states, in a manner analogous to an optical Wollaston prism. Such a Wollaston prism can be used to encode the trajectory of neutrons into the Larmor phase associated with their spin degree of freedom. This encoding can be used for neutron phase-contrast radiography and in spin echo scattering angle measurement (SESAME). In this paper, we show that magnetic Wollaston prisms with highly uniform magnetic fields and low Larmor phase aberration can be constructed to preserve neutron polarization using high temperature superconducting (HTS) materials. The Meissner effect of HTS films is used to confine magnetic fields produced electromagnetically by current-carrying HTS tape wound on suitably shaped soft iron pole pieces. The device is cooled to ?30 K by a closed cycle refrigerator, eliminating the need to replenish liquid cryogens and greatly simplifying operation and maintenance. A HTS film ensures that the magnetic field transition within the prism is sharp, well-defined, and planar due to the Meissner effect. The spin transport efficiency across the device was measured to be ?98.5% independent of neutron wavelength and energizing current. The position-dependent Larmor phase of neutron spins was measured at the NIST Center for Neutron Research facility and found to agree well with detailed simulations. The phase varies linearly with horizontal position, as required, and the neutron beam shows little depolarization. Consequently, the device has advantages over existing devices with similar functionality and provides the capability for a large neutron beam (20 mm 30 mm) and an increase in length scales accessible to SESAME to beyond 10 ?m. With further improvements of the external coupling guide field in the prototype device, a larger neutron beam could be employed.

  5. Energy Savings Potential and Research & Development Opportunities for Commercial Refrigeration

    SciTech Connect (OSTI)

    none,

    2009-09-01

    This study documents the energy consumption of commercial refrigeration equipment (CRE) in the U.S. and evaluated the energy savings potential of various technologies and energy efficiency measures that could be applied to such equipment. The study provided an overview of CRE applications, assessed the energy-savings potential of CRE in the U.S., outline key barriers to adoption of energy-savings technologies, and recommended opportunities for advanced energy saving technology research. The study was modeled after an earlier 1996 report by Arthur D. Little, Inc., and updated key information, examined more equipment types, and outlined long-term research and development opportunities.

  6. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    (Gd). While some of this research is focused on materials that would operate near room temperature, Karotsis et al. here investigate the magnetic cooling properties of...

  7. Materials Videos

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Videos Materials

  8. Physical Attraction: The Mysteries of Magnetism

    SciTech Connect (OSTI)

    Stohr, Joachim

    2004-12-14

    Most people have intuitive associations with the word 'magnetism' based on everyday life: refrigerator magnets, the compass, north and south poles, or someone's 'magnetic personality'. Few people, however, realize how complicated the phenomenon really is, how much research still deals with the topic today, and how much it penetrates our modern industrialized world - from electricity, wireless communication at the speed of light to magnetic sensors in cars and data storage in computers. Stohr's lecture will provide a glimpse at the magic and science behind magnetism: its long history, scientific breakthroughs in its understanding, and its use in our modern society. In the process Stohr will show how research at SSRL/SLAC is addressing some of the forefront issues in magnetism research and technology today.

  9. A Comparative Study on the Environmental Impact of CO2 Supermarket Refrigeration Systems

    SciTech Connect (OSTI)

    Beshr, Mohamed; Aute, Vikrant; Sharma, Vishaldeep; Abdelaziz, Omar; Fricke, Brian A; Radermacher, Reinhard

    2014-01-01

    Supermarket refrigeration systems have high environmental impact due to their large refrigerant charge and high leak rates. Accordingly, the interest in using natural refrigerants, such as carbon dioxide (CO2), and new refrigerant blends with low GWP in such systems is increasing. In this paper, an open-source Life Cycle Climate Performance (LCCP) framework is presented and used to compare the environmental impact of three supermarket refrigeration systems. These systems include a transcritical CO2 booster system, a cascade CO2/N-40 system, and a baseline R-404A multiplex direct expansion system. The study is performed for cities representing different climates within the USA using EnergyPlus to simulate the systems' hourly performance. Finally, a parametric analysis is performed to study the impact of annual leak rate on the systems' LCCP.

  10. HFC-134A and HCFC-22 supermarket refrigeration demonstration and laboratory testing. Phase I. Final report

    SciTech Connect (OSTI)

    1996-04-01

    Aspen Systems and a team of nineteen agencies and industry participants conducted a series of tests to determine the performance of HFC-134a, HCFC-22, and CFC-502 for supermarket application. This effort constitutes the first phase of a larger project aimed at carrying out both laboratory and demonstration tests of the most viable HFC refrigerants and the refrigerants they replace. The results of the Phase I effort are presented in the present report. The second phase of the project has also been completed. It centered on testing all viable HFC replacement refrigerants for CFC-502. These were HFC-507, HFC-404A, and HFC-407A. The latter results are published in the Phase II report for this project. As part of Phase I, a refrigeration rack utilizing a horizontal open drive screw compressor was constructed in our laboratory. This refrigeration rack is a duplicate of one we have installed in a supermarket in Clifton Park, NY.

  11. Heat pump/refrigerator using liquid working fluid

    DOE Patents [OSTI]

    Wheatley, John C.; Paulson, Douglas N.; Allen, Paul C.; Knight, William R.; Warkentin, Paul A.

    1982-01-01

    A heat transfer device is described that can be operated as a heat pump or refrigerator, which utilizes a working fluid that is continuously in a liquid state and which has a high temperature-coefficient of expansion near room temperature, to provide a compact and high efficiency heat transfer device for relatively small temperature differences as are encountered in heating or cooling rooms or the like. The heat transfer device includes a pair of heat exchangers that may be coupled respectively to the outdoor and indoor environments, a regenerator connecting the two heat exchangers, a displacer that can move the liquid working fluid through the heat exchangers via the regenerator, and a means for alternately increasing and decreasing the pressure of the working fluid. The liquid working fluid enables efficient heat transfer in a compact unit, and leads to an explosion-proof smooth and quiet machine characteristic of hydraulics. The device enables efficient heat transfer as the indoor-outdoor temperature difference approaches zero, and enables simple conversion from heat pumping to refrigeration as by merely reversing the direction of a motor that powers the device.

  12. Waste Heat Powered Ammonia Absorption Refrigeration Unit for LPG Recovery

    SciTech Connect (OSTI)

    Donald C, Energy Concepts Co.; Lauber, Eric, Western Refining Co.

    2008-06-20

    An emerging DOE-sponsored technology has been deployed. The technology recovers light ends from a catalytic reformer plant using waste heat powered ammonia absorption refrigeration. It is deployed at the 17,000 bpd Bloomfield, New Mexico refinery of Western Refining Company. The technology recovers approximately 50,000 barrels per year of liquefied petroleum gas that was formerly being flared. The elimination of the flare also reduces CO2 emissions by 17,000 tons per year, plus tons per year reductions in NOx, CO, and VOCs. The waste heat is supplied directly to the absorption unit from the Unifiner effluent. The added cooling of that stream relieves a bottleneck formerly present due to restricted availability of cooling water. The 350oF Unifiner effluent is cooled to 260oF. The catalytic reformer vent gas is directly chilled to minus 25oF, and the FCC column overhead reflux is chilled by 25oF glycol. Notwithstanding a substantial cost overrun and schedule slippage, this project can now be considered a success: it is both profitable and highly beneficial to the environment. The capabilities of directly-integrated waste-heat powered ammonia absorption refrigeration and their benefits to the refining industry have been demonstrated.

  13. Couples Magnetic and Structural Transitions in High-Purity Dy and Gd5SbxGe4-x

    SciTech Connect (OSTI)

    Alexander S. Chernyshov

    2006-08-09

    Magnetic materials exhibiting magnetic phase transitions simultaneously with structural rearrangements of their crystal lattices hold a promise for numerous applications including magnetic refrigeration, magnetomechanical devices and sensors. We undertook a detailed study of a single crystal of dysprosium metal, which is a classical example of a system where magnetic and crystallographic sublattices can be either coupled or decoupled from one another. Magnetocaloric effect, magnetization, ac magnetic susceptibility, and heat capacity of high purity single crystals of dysprosium have been investigated over broad temperature and magnetic field intervals with the magnetic field vector parallel to either the a- or c-axes of the crystal. Notable differences in the behavior of the physical properties when compared to Dy samples studied in the past have been observed between 110 K and 125 K, and between 178 K and {approx}210 K. A plausible mechanism based on the formation of antiferromagnetic clusters in the impure Dy has been suggested in order to explain the reduction of the magnetocaloric effect in the vicinity of the Neel point. Experimental and theoretical investigations of the influence of commensurability effects on the magnetic phase diagram and the value of the magnetocaloric effect have been conducted. The presence of newly found anomalies in the physical properties has been considered as evidence of previously unreported states of Dy. The refined magnetic phase diagram of dysprosium with the magnetic field vector parallel to the a-axis of a crystal has been constructed and discussed. The magnetic and crystallographic properties of Gd{sub 5}Sb{sub x}Ge{sub 4-x} pseudo-binary system were studied by x-ray diffraction (at room temperature), heat capacity, ac-magnetic susceptibility, and magnetization in the temperature interval 5-320 K in magnetic fields up to 100 kOe. The magnetic properties of three composition (x = 0.5, 1,2) were examined in detail. The Gd{sub 5}Sb{sub 2}Ge{sub 2} compound that adopts Tm{sub 5}Sb{sub 2}Si{sub 2}-type of structure (space group is Cmca), shows a second order FM-PM transition at 200 K, whereas Gd{sub 5}Sb{sub x}Ge{sub 4-x} compounds for x = 0.5 and x = 1 (Sm{sub 5}Ge{sub 4}-type of structure, space group is Pnma) exhibit first order phase transformations at 45 K and 37 K, respectively.

  14. ADVANCED UNDERGROUND GAS STORAGE CONCEPTS REFRIGERATED-MINED CAVERN STORAGE

    SciTech Connect (OSTI)

    1998-09-01

    Limited demand and high cost has prevented the construction of hard rock caverns in this country for a number of years. The storage of natural gas in mined caverns may prove technically feasible if the geology of the targeted market area is suitable; and economically feasible if the cost and convenience of service is competitive with alternative available storage methods for peak supply requirements. It is believed that mined cavern storage can provide the advantages of high delivery rates and multiple fill-withdrawal cycles in areas where salt cavern storage is not possible. In this research project, PB-KBB merged advanced mining technologies and gas refrigeration techniques to develop conceptual designs and cost estimates to demonstrate the commercialization potential of the storage of refrigerated natural gas in hard rock caverns. Five regions of the U.S.A. were studied for underground storage development and PB-KBB reviewed the literature to determine if the geology of these regions was suitable for siting hard rock storage caverns. Area gas market conditions in these regions were also studied to determine the need for such storage. Based on an analysis of many factors, a possible site was determined to be in Howard and Montgomery Counties, Maryland. The area has compatible geology and a gas industry infrastructure for the nearby market populous of Baltimore and Washington D.C.. As Gas temperature is lowered, the compressibility of the gas reaches an optimum value. The compressibility of the gas, and the resultant gas density, is a function of temperature and pressure. This relationship can be used to commercial advantage by reducing the size of a storage cavern for a given working volume of natural gas. This study looks at this relationship and and the potential for commercialization of the process in a storage application. A conceptual process design, and cavern design were developed for various operating conditions. Potential site locations were considered and a typical plant layout was developed. In addition a geomechanical review of the proposed cavern design was performed, evaluating the stability of the mine rooms and shafts, and the effects of the refrigerated gas temperatures on the stability of the cavern. Capital and operating cost estimates were also developed for the various temperature cases considered. The cost estimates developed were used to perform a comparative market analysis of this type of gas storage system to other systems that are commercially used in the region of the study.

  15. Investigation of pressure drop in capillary tube for mixed refrigerant Joule-Thomson cryocooler

    SciTech Connect (OSTI)

    Ardhapurkar, P. M.; Sridharan, Arunkumar; Atrey, M. D.

    2014-01-29

    A capillary tube is commonly used in small capacity refrigeration and air-conditioning systems. It is also a preferred expansion device in mixed refrigerant Joule-Thomson (MR J-T) cryocoolers, since it is inexpensive and simple in configuration. However, the flow inside a capillary tube is complex, since flashing process that occurs in case of refrigeration and air-conditioning systems is metastable. A mixture of refrigerants such as nitrogen, methane, ethane, propane and iso-butane expands below its inversion temperature in the capillary tube of MR J-T cryocooler and reaches cryogenic temperature. The mass flow rate of refrigerant mixture circulating through capillary tube depends on the pressure difference across it. There are many empirical correlations which predict pressure drop across the capillary tube. However, they have not been tested for refrigerant mixtures and for operating conditions of the cryocooler. The present paper assesses the existing empirical correlations for predicting overall pressure drop across the capillary tube for the MR J-T cryocooler. The empirical correlations refer to homogeneous as well as separated flow models. Experiments are carried out to measure the overall pressure drop across the capillary tube for the cooler. Three different compositions of refrigerant mixture are used to study the pressure drop variations. The predicted overall pressure drop across the capillary tube is compared with the experimentally obtained value. The predictions obtained using homogeneous model show better match with the experimental results compared to separated flow models.

  16. Experimental study and analysis on components of a thermoacoustic refrigerator and thermoacoustic prime mover

    SciTech Connect (OSTI)

    Nohtomi, Makoto; Katsuta, Masafumi

    1999-07-01

    A thermoacoustic refrigerator and a thermoacoustic prime mover, due to its simple structure, would serve as very desirable systems because thermoacoustic prime movers can be driven with the waste heat such as an exhaust gas from engines, and with heat from the nature such as sunlight and a geothermal heat. The thermoacoustic refrigerator and the thermoacoustic prime mover combined would serve as a perfect cooling system without moving parts, CFC's and HFC's. Thus this Thermoacoustic-driven Thermoacoustic Refrigerator will replace the previous paper compression refrigeration system. The authors set up the thermoacoustic refrigerator and thermoacoustic prime mover to investigate the fundamental characteristics. On the refrigerator tests, dimensions of the stack are varied as a parameter of experiments. As a result, influences of the stack configuration on the performance are confirmed, so the design method for the optimum dimension to attain the large temperature difference can be indicated. About the prime mover tests, fundamental characteristics of stack dimensions is checked. The way to improve the thermal efficiency of the prime mover is mentioned in terms of the operating condition. Numerical calculations about the refrigerator are made which is based on the enthalpy flow model by Radebaugh. The result of calculations has a good agreement in quality with the experimental results, so the propriety of this model is confirmed.

  17. IMPACTS OF REFRIGERANTLINE LENGTH ON SYSTEM EFFICIENCY IN RESIDENTIAL HEATING AND COOLING SYSTEMS USING REFRIGERANT DISTRIBUTION.

    SciTech Connect (OSTI)

    ANDREWS, J.W.

    2001-04-01

    The effects on system efficiency of excess refrigerant line length are calculated for an idealized residential heating and cooling system. By excess line length is meant refrigerant tubing in excess of the 25 R provided for in standard equipment efficiency test methods. The purpose of the calculation is to provide input for a proposed method for evaluating refrigerant distribution system efficiency. A refrigerant distribution system uses refrigerant (instead of ducts or pipes) to carry heat and/or cooling effect from the equipment to the spaces in the building in which it is used. Such systems would include so-called mini-splits as well as more conventional split systems that for one reason or another have the indoor and outdoor coils separated by more than 25 ft. This report performs first-order calculations of the effects on system efficiency, in both the heating and cooling modes, of pressure drops within the refrigerant lines and of heat transfer between the refrigerant lines and the space surrounding them.

  18. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  19. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  20. Cool Magnetic Molecules

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability

  1. Magnetic Correlations in the Quasi-Two-Dimensional Semiconducting...

    Office of Scientific and Technical Information (OSTI)

    dramatically. Establishing the nature of the bulk material's magnetism is necessary for understanding the thin-film magnetic behavior and the material's possible applications. ...

  2. National High Magnetic Field Laboratory moves closer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    researchers to carefully tune material parameters while perfectly reproducing the non-invasive magnetic field. Such high magnetic fields confine electrons to nanometer scale...

  3. Disorder-Induced Microscopic Magnetic Memory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired...

  4. Experimental investigation of an advanced adsorption refrigeration cycle

    SciTech Connect (OSTI)

    Saha, B.B.; Kashiwagi, Takao

    1997-12-31

    Experimental measurements are made for a silica gel-water advanced absorption refrigeration chiller (1.2-kW [4,095-Btu/h] cooling capacity) to evaluate its performance under different temperature and adsorption/desorption cycle time conditions. This paper describes the operating principle of the chiller, outlines the experimental hardware, and discusses results obtained by varying the cooling and hot water inlet temperatures and adsorption/desorption cycle times, as well as their agreement with the simulated results given by a lumped parameter model. The chiller performance is analyzed in terms of cooling capacity and coefficient of performance (COP). Excellent qualitative agreement was obtained between the experimental data and simulated results. The results showed the advanced three-stage cycle to be particularly well suited for operation with low-grade-temperature waste heat as the driving source, since it worked with small regenerating temperature lifts (heat source-heat sink temperature) of 10 to 30 K.

  5. Triple effect absorption chiller utilizing two refrigeration circuits

    SciTech Connect (OSTI)

    DeVault, R.C.

    1988-03-22

    This patent describes a heat absorption method for an absorption chiller. It comprises: providing a firs absorption system circuit for operation within a first temperature range, providing a second absorption system circuit for operation within a second temperature range; heat exchanging refrigerant and absorber solution; thermal communication with an external heat load. This patent describes a heat absorption apparatus for use as an absorption chiller. It includes: a first absorption system circuit for operation within a first temperature range; a second absorption system circuit for operation within a second temperature range which has a lower maximum temperature relative to the first temperature range; the first circuit having generator means, condenser means, evaporator means, and absorber means operatively connected together; the second circuit having generator means condenser means, evaporator means, and absorber means operative connected together; and the first circuit condenser means and the first circuit absorber means being in heat exchange communication with the second circuit generator means.

  6. Theoretical evaluation of the optimal performance of a thermoacoustic refrigerator

    SciTech Connect (OSTI)

    Minner, B.L.; Braun, J.E.; Mongeau, L.G.

    1997-12-31

    Theoretical models were integrated with a design optimization tool to allow estimates of the maximum coefficient of performance for thermoacoustic cooling systems. The system model was validated using experimental results for a well-documented prototype. The optimization tool was then applied to this prototype to demonstrate the benefits of systematic optimization. A twofold increase in performance was predicted through the variation of component dimensions alone, while a threefold improvement was estimated when the working fluid parameters were also considered. Devices with a similar configuration were optimized for operating requirements representative of a home refrigerator. The results indicate that the coefficients of performance are comparable to those of existing vapor-compression equipment for this application. In addition to the choice of working fluid, the heat exchanger configuration was found to be a critical design factor affecting performance. Further experimental work is needed to confirm the theoretical predictions presented in this paper.

  7. Super Efficient Refrigerator Program (SERP) evaluation. Volume 1: Process evaluation

    SciTech Connect (OSTI)

    Sandahl, L.J.; Ledbetter, M.R.; Chin, R.I.; Lewis, K.S.; Norling, J.M.

    1996-01-01

    The Pacific Northwest National Laboratory (PNNL) conducted this study for the US Department of Energy (DOE) as part of the Super Efficient Refrigerator Program (SERP) Evaluation. This report documents the SERP formation and implementation process, and identifies preliminary program administration and implementation issues. The findings are based primarily on interviews with those familiar with the program, such as utilities, appliance manufacturers, and SERP administrators. These interviews occurred primarily between March and April 1995, when SERP was in the early stages of program implementation. A forthcoming report will estimate the preliminary impacts of SERP within the industry and marketplace. Both studies were funded by DOE at the request of SERP Inc., which sought a third-party evaluation of its program.

  8. Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets

    SciTech Connect (OSTI)

    2010-10-01

    Broad Funding Opportunity Announcement Project: GE is using nanomaterials technology to develop advanced magnets that contain fewer rare earth materials than their predecessors. Nanomaterials technology involves manipulating matter at the atomic or molecular scale, which can represent a stumbling block for magnets because it is difficult to create a finely grained magnet at that scale. GE is developing bulk magnets with finely tuned structures using iron-based mixtures that contain 80% less rare earth materials than traditional magnets, which will reduce their overall cost. These magnets will enable further commercialization of HEVs, EVs, and wind turbine generators while enhancing U.S. competitiveness in industries that heavily utilize these alternatives to rare earth minerals.

  9. Table B36. Refrigeration Equipment, Number of Buildings and Floorspace, 1999

    U.S. Energy Information Administration (EIA) Indexed Site

    6. Refrigeration Equipment, Number of Buildings and Floorspace, 1999" ,"Number of Buildings (thousand)",,,,,"Total Floorspace (million square feet)" ,"All Buildings","All Buildings with Refrigeration Equipment","Type of Equipment (more than one may apply)",,,"All Buildings","All Buildings with Refrigeration Equipment","Type of Equipment (more than one may apply)" ,,,"Walk-In","Open Cases or

  10. The Super Efficient Refrigerator Program: Case study of a Golden Carrot program

    SciTech Connect (OSTI)

    Eckert, J B

    1995-07-01

    The work in this report was conducted by the Analytic Studies Division (ASD) of the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy, Office of Building Technologies. This case study describes the development and implementation of the Super Efficient Refrigerator Program (SERP), which awarded $30 million to the refrigerator manufacturer that developed and commercialized a refrigerator that exceeded 1993 federal efficiency standards by at least 25%. The program was funded by 24 public and private utilities. As the first Golden Carrot program to be implemented in the United States, SERP was studied as an example for future `market-pull` efforts.

  11. Synchronous temperature rate control and apparatus for refrigeration with reduced energy consumption

    DOE Patents [OSTI]

    Gomes, Alberto Regio; Keres, Stephen L.; Kuehl, Steven J.; Litch, Andrew D.; Richmond, Peter J.; Wu, Guolian

    2015-09-22

    A refrigerator appliance configuration, and associated methods of operation, for an appliance with a controller, a condenser, at least one evaporator, a compressor, and two refrigeration compartments. The configuration may be equipped with a variable-speed or variable-capacity compressor, variable speed evaporator or compartment fans, a damper, and/or a dual-temperature evaporator with a valve system to control flow of refrigerant through one or more pressure reduction devices. The controller, by operation of the compressor, fans, damper and/or valve system, depending on the appliance configuration, synchronizes alternating cycles of cooling each compartment to a temperature approximately equal to the compartment set point temperature.

  12. Triple-effect absorption refrigeration system with double-condenser coupling

    DOE Patents [OSTI]

    DeVault, R.C.; Biermann, W.J.

    1993-04-27

    A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

  13. Triple-effect absorption refrigeration system with double-condenser coupling

    DOE Patents [OSTI]

    DeVault, Robert C.; Biermann, Wendell J.

    1993-01-01

    A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

  14. Application of JLab 12GeV helium refrigeration system for the FRIB accelerator at MSU

    SciTech Connect (OSTI)

    Ganni, Venkatarao; Knudsen, Peter N.; Arenius, Dana M.; Casagrande, Fabio

    2014-01-01

    The planned approach to have a turnkey helium refrigeration system for the MSU-FRIB accelerator system, encompassing the design, fabrication, installation and commissioning of the 4.5-K refrigerator cold box(es), cold compression system, warm compression system, gas management, oil removal and utility/ancillary systems, was found to be cost prohibitive. Following JLab’s suggestion, MSU-FRIB accelerator management made a formal request to evaluate the applicability of the recently designed 12GeV JLab cryogenic system for this application. The following paper will outline the findings and the planned approach for the FRIB helium refrigeration system.

  15. Application of JLab 12GeV helium refrigeration system for the FRIB accelerator at MSU

    SciTech Connect (OSTI)

    Ganni, V.; Knudsen, P.; Arenius, D.; Casagrande, F.

    2014-01-29

    The planned approach to have a turnkey helium refrigeration system for the MSU-FRIB accelerator system, encompassing the design, fabrication, installation and commissioning of the 4.5-K refrigerator cold box(es), cold compression system, warm compression system, gas management, oil removal and utility/ancillary systems, was found to be cost prohibitive. Following JLab’s suggestion, MSU-FRIB accelerator management made a formal request to evaluate the applicability of the recently designed 12GeV JLab cryogenic system for this application. The following paper will outline the findings and the planned approach for the FRIB helium refrigeration system.

  16. Development and Evaluation of a Sandia Cooler-based Refrigerator Condenser

    SciTech Connect (OSTI)

    Johnson, Terry A.; Kariya, Harumichi Arthur; Leick, Michael T.; Zimmerman, Mark D.; Li, Manjie; Du, Yilin; Lee, Hoseong; Hwang, Yunho; Radermacher, Reinhard

    2015-07-01

    This report describes the first design of a refrigerator condenser using the Sandia Cooler, i.e. air - bearing supported rotating heat - sink impeller. The project included ba seline performance testing of a residential refrigerator, analysis and design development of a Sandia Cooler condenser assembly including a spiral channel baseplate, and performance measurement and validation of this condenser system as incorporated into the residential refrigerator. Comparable performance was achieved in a 60% smaller volume package. The improved modeling parameters can now be used to guide more optimized designs and more accurately predict performance.

  17. Magnetic infrasound sensor

    DOE Patents [OSTI]

    Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)

    2006-11-14

    A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.

  18. Magnetic properties and magnetocaloric effects of Gd{sub x}Er{sub 1−x}Ga (0 ≤ x ≤ 1) compounds

    SciTech Connect (OSTI)

    Zheng, X. Q.; Wang, L. C.; Wu, R. R.; Hu, F. X.; Sun, J. R.; Shen, B. G.; Chen, J.

    2014-05-07

    We carefully studied the magnetic properties and magnetocaloric effect of Gd{sub x}Er{sub 1-x}Ga (0 ≤ x ≤ 1) compounds. The Gd{sub x}Er{sub 1-x}Ga compounds undergo two magnetic transitions with temperature increasing: spin-reorientation or antiferromagnetic-to-ferromagnetic (FM) transition and FM-to-paramagnetic transition. As the content of Gd increases from 0 to 1, the transition temperature in low temperature region changes from 15 K to 66 K and the Curie temperature increases obviously from 30 K to 181.9 K. Although the maximum value of magnetic entropy change (ΔS{sub M}) for Gd{sub x}Er{sub 1−x}Ga decreases with the increase of x, the refrigerant capacity (RC) improves remarkably compared with that of ErGa compound. Table-like ΔS{sub M} curves are observed for the compounds with x = 0.1, 0.2, 0.3, and 0.4, which are very useful for real cooling applications. And Gd{sub 0.2}Er{sub 0.8}Ga and Gd{sub 0.3}Er{sub 0.7}Ga compounds show better magnetocaloric features than others in this series under considerations of both ΔS{sub M} and RC. The results of this series of compounds show us a possible way to design and improve the magnetic refrigerant materials by making some substitutions.

  19. Magnetic Material for PM Motors

    Broader source: Energy.gov [DOE]

    2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, May 18-22, 2009 -- Washington D.C.

  20. Microsoft Word - TRILATERAL CRITICAL MATERIALS WORKSHOP Summary...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ... magnetic mechanisms (for nanocomposites, non-rare-earth materials, and neodymium-iron-boron magnets). * Techniques to enhance the stability and texture of nanocomposite structures ...