A Study on the Enhancement of the Cooling Structure for In-wheel Motor

인휠 모터의 냉각 구조 개선에 관한 연구

  • Kim, Dae Geon (Green Car Powertrain R&D Division, Korea Automotive Technology Institute) ;
  • Kim, Sung Chul (Green Car Powertrain R&D Division, Korea Automotive Technology Institute)
  • 김대건 (자동차부품연구원 그린카파워트레인연구본부) ;
  • 김성철 (자동차부품연구원 그린카파워트레인연구본부)
  • Received : 2011.11.01
  • Accepted : 2012.02.15
  • Published : 2013.01.01


Recently, the automobile of the future will be able to substitute an electric vehicle for an internal combustion engine, so the following research is actively in the process of advancing. A traction motor is one of the core parts which compose the electric vehicle. Especially, it is difficult to connect cooling water piping to an in-wheel motor because the in-wheel motor is located within the wheel structure. This structure has disadvantage for closed type and air cooling, so the cooling design of motor housing and internal in-wheel motor is important. In this study, thermo-flow analysis of the in-wheel motor for vehicles was performed in consideration of ram air effect. In order to improve cooling efficiency of the motor, we variously changed geometries of housing and internal shape. As a result, we found that the cooling efficiency was most excellent, in case the cooling groove direction was same with air flow direction and arranged densely. Furthermore, we investigated the cooling performance enhancement with respect to variable geometries of internal in-wheel motor.


Supported by : 지식경제부


  1. J. H. Jung, S. C. Kim, H. C. Kim, J. P. Won and W. Kim, "A Study on Cooling Performance Analysis of In-Wheel Motor," KSAE Annual Conference Proceedings, pp.3034-3038, 2009.
  2. J. H. Jung, S. C. Kim and J. P. Hong, "A Study on Cooling Performance of In-wheel for Green Car," Transactions of KSAE, Vol.20, No.1, pp.61-67, 2012.
  3. P. Turnbull, J. Kuo, R. Schultz and B. Turner, "Thermal Analysis of an Electric Machine for a Hybrid Vehicle," SAE 2004-01-0565, 2004.
  4. Y. Zhang, Y. Shen and W. Zhang, "Optimized Design of the Cooling System for an Articulated Dump Truck's Electric Drive System," SAE 2010-01-0504, 2010.
  5. K. Farsane, P. Desevaux and P. K. Panday, "Experimental Study of the Cooling of a Closed Type Electric Motor," Applied Thermal Engineering, Vol.20, No.14, pp.1321-1334, 2000.
  6. D. R. Lee, "Investigation of Cooling Performance of the Driving Motor Utilizing Heat Pipe," Transactions of KSPSE, Vol.10, No.4, pp.11-16, 2006.
  7. D. B. Choi, S. T. Kim , S. H. Jung, J. H. Kim and Y. K. Kim, "Thermal Characteristics of the High Frequency Motor Spindle according to the Bearing Preloads and Cooling Conditions," Transactions of KSMTE, Vol.14, No.6, pp.31- 36, 2005.
  8. SC/Tetra Version 7 User's Guide Solver Reference, 2007.

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