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2013 Vol.32, Issue 3 Preview Page
캠축의 구조 진동 응답 및 응력
Myung-Jin Choi1*
최 명진1*
1경희대학교 공과대학 기계공학과, 산학협력기술연구원
*Corresponding Author
31 May 2013. pp. 208-213
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Abstract

To get vibration responses, a camshaft is modelled as an unbalanced multiple rotor bearing system. Because of complex geometry and complicated load conditions, the finite element method is used. After the finite element equation of the system is constructed, Newmark’s method is used to get the vibration responses. Whirl vibration responses of a V-8 engine camshaft are estimated and compared with measured responses. After the fluctuating stresses are obtained, fatigue analysis is performed based upon the modified Goodman’s equation. Stress concentration effects are considered. In the whirl vibration of camshafts, the bending effect is dominant, and the bending deformation is dependent upon the span length between the adjacent bearing journals. For high speeds, the fluctuations of excitation forces are large, and it is known that nonlinear time varying bearing coefficients should be used for analysis.

Keywords
Camshaft vibration
Rotor bearing system
Whirl vibration
Vibrational stress
Unbalanced vibration
Fluid film journal bearing

캠축의 진동 응답을 구하기 위해 캠축을 불균형 다단계 로터 베어링계로 해석하였으며, 복잡한 형상과 하중 조건을 고려하여 유한요소법을 사용하였다. 유한요소 방정식을 유도한 후에 Newmark 법을 사용하여 진동 응답을 구하였다. V-8 엔진 캠축의 회전 진동 응답을 구하여 측정치와 비교하였다. 캠축의 변동 응력을 구하고, 응력 집중 효과를 고려한 다음에 Goodmann 식에 근거하여 피로 해석을 수행하였다. 캠축의 회전 진동에서는 굽힘 효과가 지배적이며, 인접하는 베어링 간격에 가장 큰 영향을 받는다. 캠축에 가해지는 하중의 변화가 클 경우에는 하중의 변화에 상응하여 시간에 따라 변화하는 베어링 계수를 적용하여야 함을 알 수 있었다.

키워드
캠축 진동
로터 베어링 시스템
회전 진동
진동 응력
불균형 진동
유막 저어널 베어링
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Information
  • Publisher :The Acoustical Society of Korea
  • Publisher(Ko) :한국음향학회
  • Journal Title :The Journal of the Acoustical Society of Korea
  • Journal Title(Ko) :한국음향학회지
  • Volume : 32
  • No :3
  • Pages :208-213
  • Received Date : 2012-10-11
  • Revised Date : 2013-01-08
  • Accepted Date : 2013-02-06
  • DOI :https://doi.org/10.7776/ASK.2013.32.3.208
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