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Title: Anisotropic Thermal Response of Packed Copper Wire

The apparent thermal conductivity of packed copper wire test specimens was measured parallel and perpendicular to the axis of the wire using laser flash, transient plane source, and transmittance test methods. Approximately 50% wire packing efficiency was produced in the specimens using either 670- or 925-μm-diameter copper wires that both had an insulation coating thickness of 37 μm. The interstices were filled with a conventional varnish material and also contained some remnant porosity. The apparent thermal conductivity perpendicular to the wire axis was about 0.5–1 W/mK, whereas it was over 200 W/mK in the parallel direction. The Kanzaki model and an finite element analysis (FEA) model were found to reasonably predict the apparent thermal conductivity perpendicular to the wires but thermal conductivity percolation from nonideal wire-packing may result in their underestimation of it.
 [1] ;  [2] ;  [2] ;  [1] ;  [1] ;  [1] ;  [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  3. Univ. of Tennessee, Knoxville, TN (United States). Department of Electrical Engineering and Computer Science
Publication Date:
Report Number(s):
Journal ID: ISSN 1948-5085
Grant/Contract Number:
AC05-00OR22725; AC36-08GO28308
Accepted Manuscript
Journal Name:
Journal of Thermal Science and Engineering Applications
Additional Journal Information:
Journal Volume: 9; Journal Issue: 4; Journal ID: ISSN 1948-5085
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
Country of Publication:
United States
42 ENGINEERING; 36 MATERIALS SCIENCE; apparent thermal conductivity; transverse isotropy; laser flash; transient plane source; thermal transmittance; representative volume element; thermal conductivity percolation; 30 DIRECT ENERGY CONVERSION; copper; wire; anisotropy; thermal conductivity; packing; shipments; packings; cushioning; transients; dynamics; lasers; coating processes; coatings
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1352996