Tribology and Lubricants

Korean Tribology Society (한국트라이볼로지학회)
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Wear Analysis of Engine Bearings at Constant Shaft Angular Speed on a Firing State - Part I: Understanding of Bearing Wear Region

파이어링 상태의 일정 축 각속도에서 엔진 베어링의 마모 해석 - Part I: 베어링 마모발생 부위 파악

  • Chun, Sang Myung (School of Mechanical Engineering, Dept. of Automotive Engineering, Hoseo University)
  • 전상명 (호서대학교 기계공학부 자동차공학전공)
  • Received : 2018.04.02
  • Accepted : 2018.05.25
  • Published : 2018.06.30
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Abstract

The purpose of Part I of this study is to find the potential region of wear scarring on engine journal bearings operating at a constant angular crank shaft velocity under firing conditions. To do this, we calculate the applied loads and eccentricities of a big-end journal bearing installed on a four-stroke and four-cylinder engine at every crank angle. Then, we find potential wear regions, such as a minimum oil film thickness, at every crank angle below most oil film thickness scarring wear (MOFTSW) obtained based on the concept of the centerline average surface roughness. Thus, the wear region is defined as a set of each film thickness below the MOFTSW at every crank angle. In this region, the wear volume changes according to the wear depth and wear angle, depending on the minimum oil film thickness at every crank angle. The total wear volume is the summation during one cycle. Graphical views of the region in the two-dimensional coordinates show the crank angle and bearing angle along the journal center path, indicating the position of the minimum oil film thickness. The results of wear analysis show that the possible wear region is located at a few tens of angles behind the upper center of a big-end bearing at maximum power rpm.

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References

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