A Study on Cooling Performance of In-wheel Motor for Green Car

그린카용 인휠 모터의 냉각 성능에 관한 연구

  • Jung, Jung-Hun (Green Car Powertrain R&D Division, Korea Automotive Technology Institute) ;
  • Kim, Sung-Chul (Green Car Powertrain R&D Division, Korea Automotive Technology Institute) ;
  • Hong, Jung-Pyo (Department of Automotive Engineering, Hanyang University)
  • 정정훈 (자동차부품연구원 그린카 파워트레인연구본부) ;
  • 김성철 (자동차부품연구원 그린카 파워트레인연구본부) ;
  • 홍정표 (한양대학교 자동차공학과)
  • Received : 2011.01.12
  • Accepted : 2011.03.20
  • Published : 2012.01.01


The in-wheel motor used in green car was designed and constructed for an electric direct-drive traction system. It is difficult to connect cooling water piping because the in-wheel motor is located within the wheel structure. In the air cooling structure for the in-wheel motor, a outer surface on the housing is provided with cooling grooves to increase the heat transfer area. In this study, we carried out the analysis on the fluid flow and thermal characteristics of the in-wheel motor under the effects of motor speed and heat generation. In order to check the problem of heat release, the analysis has been performed using conjugate heat transfer (conduction and convection). As a result, flow fields and temperature distribution inside the in-wheel motor were obtained for base speed condition (1250 rpm) and maximum speed condition (5000 rpm). Also, the thermo-flow characteristics analysis of in-wheel motor for vehicles was performed in consideration of ram air effect. Therefore, we checked the feasibility of the air cooling for the housing geometry having cooling grooves and investigated the cooling performance enhancement.


Supported by : 지식경제부


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