Tribology and Lubricants

Korean Tribology Society (한국트라이볼로지학회)
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A Study on the Wet Clutch Pattern Design for the Drag Torque Reduction in Wet DCT System

습식 DCT의 드래그 토크 저감을 위한 클러치 패드 유로 설계

  • Cho, Junghee (Graduate School, Dept. of Automotive Engineering, Kookmin University) ;
  • Han, Juneyeol (Graduate School, Dept. of Automotive Engineering, Kookmin University) ;
  • Kim, Woo-Jung (Hyundai Powertech, Ltd.) ;
  • Jang, Siyoul (Dept. of Automotive Engineering, KookMin University)
  • 조정희 (국민대학교 자동차공학 전문대학원) ;
  • 한준열 (국민대학교 자동차공학 전문대학원) ;
  • 김우정 (현대파워텍(주)) ;
  • 장시열 (국민대학교 자동차공학과)
  • Received : 2016.10.12
  • Accepted : 2017.03.02
  • Published : 2017.04.30
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Abstract

The drag torque in the wet clutch system of a dual clutch transmission system is investigated because it is relatively high, up to 10 of the total output torque of the engine, even when the clutch is in the disengagement state with zero torque transfer. Drag torque results from the shear resistance of the DCTF between the friction pad and separator plate. To reduce the drag torque for ensuring fuel economy, the groove pattern of the wet clutch friction pad is designed to have a high flow rate through the pattern groove. In this study, four types of groove patterns on the friction pad are designed. The volume fraction of the DCTF (VOF) and hydrodynamic pressure developments in the gap between the friction pad and separator plate are computed to correlate with the computation of the drag torque. From the computational results, it is found that a high VOF and hydrodynamics increase the drag torque resulting from the shear resistance of the DCTF. Therefore, a patterned groove design should be used for increasing the flow rate to have more air parts in the gap to reduce the drag torque. In this study, ANSYS FLUENT is used to solve the flow analysis.

Keywords

References

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Cited by

  1. Parametric analysis of the drag torque model of wet multi-plate friction clutch with groove consideration vol.70, pp.7, 2018, https://doi.org/10.1108/ILT-03-2017-0063