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Title: Experimental Characterization and Modeling of Thermal Contact Resistance of Electric Machine Stator-to-Cooling Jacket Interface Under Interference Fit Loading

Cooling of electric machines is a key to increasing power density and improving reliability. This paper focuses on the design of a machine using a cooling jacket wrapped around the stator. The thermal contact resistance (TCR) between the electric machine stator and cooling jacket is a significant factor in overall performance and is not well characterized. This interface is typically an interference fit subject to compressive pressure exceeding 5 MPa. An experimental investigation of this interface was carried out using a thermal transmittance setup using pressures between 5 and 10 MPa. Furthermore, the results were compared to currently available models for contact resistance, and one model was adapted for prediction of TCR in future motor designs.
 [1] ;  [1] ;  [2] ;  [2] ;  [2]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. UQM Technologies, Inc., Longmont, CO (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1948-5085
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Journal of Thermal Science and Engineering Applications
Additional Journal Information:
Journal Volume: 10; Journal Issue: 4; Journal ID: ISSN 1948-5085
Research Org:
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
30 DIRECT ENERGY CONVERSION; cooling; stators; thermal contact resistance; electric machines; pressure; machinery; lamination; contact resistance; press fits; aluminum; plates (structure); thermal properties
OSTI Identifier: