Results 211 to 220 of about 322 (244)
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Active and passive magnetic regenerators in gas/magnetic refrigerators
Journal of Alloys and Compounds, 1994Abstract Rare earth materials have found three types of applications in refrigeration technology. One is as passive regenerators in gas cycle refrigerators; the second is as working materials in non-regenerative or in externally regenerated/recuperated magnetic refrigerator cycles; the third is as the combined refrigerant and regenerator in active ...
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A modeling study on the geometry of active magnetic regenerator
AIP Conference Proceedings, 2012Magnetic refrigeration technology needs further development not just by the improvement of magnetocaloric properties but also the optimization of the cooling system design. One of the important problems in the cooling system design is the geometry of regenerator for the efficient heat transfer between magnetic material and fluid which is the major loss
Takenori Numazawa +3 more
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Modeling the Active Magnetic Regenerator
1992A time-dependent one-dimensional model of the Active Magnetic Regenerator (AMR) is described. The model assumes that the heat capacity of the pore fluid in the regenerator is negligible compared to the magnetic material. Measured magnetic material properties are used, including the effect of hysteresis. The variation of the fluid helium properties with
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Utilization of the Magnetic Entropy in Active Magnetic Regenerator Materials
1996The magnetic entropy associated with magnetic ordering has been determined for ~20 lanthanide materials and it varies from ~60 to ~90% of the theoretical Rln (2J+l) value. The utilization of this entropy in the magnetocaloric effect (MCE) for a 0 to 7.5 T field change, however, is much less, ranging from ~10 to ~30% at the Curie temperature (TC) for ...
K. A. Gschneidner +3 more
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Thermodynamic investigations of optimum active magnetic regenerators
Cryogenics, 1998Abstract The performance of an active magnetic regenerator refrigerator (AMRR) cycle depends strongly on the behaviour of the adiabatic magnetization temperature change ( ΔT ) as a function of material temperature ( T ) in the flow direction of the regenerator. In this study, we consider regenerators which satisfy the condition: ΔT = κT H ( T/T H )
A. Smaı̈li, R. Chahine
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A numerical model of an Active Magnetic Regenerator for refrigeration at room temperature
International Journal of Environmental Technology and Management, 2007In this paper, a numerical model of an Active Magnetic Regenerator (AMR) for refrigeration at room temperature has been evaluated. The model is based on the equation of state of a homogeneous ferromagnetic with reference to the gadolinium used as magnetocaloric substance.
APREA, Ciro +2 more
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Design of an active magnetic regenerator test apparatus
AIP Conference Proceedings, 2002The Active Magnetic Regenerator (AMR) has been shown to be a refrigeration technology with high efficiencies. Complex thermodynamic interactions in the regenerator, a shortage of suitable magnetic refrigerants, and difficulty in acquiring accurate experimental data have combined to hamper the development of AMR refrigerators.
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Active magnetic regenerator performance enhancement using passive magnetic materials
Journal of Magnetism and Magnetic Materials, 2008Abstract Magnetic refrigeration devices using permanent magnets are currently limited to useful field strengths of less than 2 T, and more practically less than 1.5 T. In this range, the useful magnetocaloric effect is less than 6 K and limits the cooling power of active magnetic regenerator (AMR) devices.
A. Rowe, A. Tura
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Cryogenic Active Magnetic Regenerator Test Apparatus
AIP Conference Proceedings, 2006An AMR Test Apparatus (AMRTA) used in experiments near room‐temperature required a number of modifications to allow for testing at cryogenic temperatures and with a 5 T magnetic field. The impacts of parasitic heat leaks, frictional heat generation, and eddy current heating in the AMRTA are analyzed.
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Demagnetizing fields in active magnetic regenerators
2014A magnetic material in an externally applied magnetic field will in general experience a spatially varying internal magnetic field due to demagnetizing effects. When the performance of active magnetic regenerators (AMRs) is evaluated using numerical models the internal field is often assumed to be spatially constant and equal to the applied field, thus
Nielsen, Kaspar Kirstein; id_orcid 0000-0001-7938-4577 +2 more
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