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Hysteresis loss in a multifilament Superconductor

  • W. J. CarrJr.
  • M. S. Walker
  • D. W. Deis
  • J. H. Murphy
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 22)

Abstract

Calorimetric measurements of the alternating field eddy current losses in three twisted filamentary, mixed-matrix superconductors were recently reported and compared with calculated losses based on the continuum model for a multifilament conductor. The measurements and comparison are extended here to the hysteresis loss. A typical cross section of the three conductors, which differ only in twist pitch, is shown in Fig. 1. The conductors, which were developed at the Los Alamos Scientific Laboratory, have a nominal composition of 3CuNi: 3Cu: INbTi and consist of 397 originally hexagonal copper-clad filaments of Nb-48wt. %Ti embedded in a Cu- 30% Ni matrix. The filaments are approximately hexagonal, being 9 μm across hexagonal fiats. The overall conductor radius is 0.026 cm and the filaments occupy a radius of about 0.024 cm. The twist pitch lengths for the three samples are 0.63,0.43, and 0.32 cm.

Keywords

Critical Current Density Bias Field Hysteresis Loss Eddy Current Loss Filament Axis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notation

d

filament diameter

Eǁ

electric field parallel to filament axis

ƒ

frequency

H

magnetic field vector

HA

applied magnetic field

Hloc

local magnetic field at a filament

Hm

amplitude of ac magnetic field Hp = magnetic field for full penetration of filament

Jc

critical current density

L

length of one complete twist

M

magnetization transverse to the filament axis

Ph/V

hysteresis loss per unit volume of conductor

R

radius of the part containing filaments

Rt

radius of conductor

λsc

volume fraction of superconductor

μ

transverse permeability

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Copyright information

© Springer Science+Business Media New York 1977

Authors and Affiliations

  • W. J. CarrJr.
    • 1
  • M. S. Walker
    • 1
  • D. W. Deis
    • 1
  • J. H. Murphy
    • 1
  1. 1.Westinghouse Research LaboratoriesPittsburghUSA

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