• 제목/요약/키워드: Elasto-Hydrodynamic Lubricatrion

검색결과 3건 처리시간 0.015초

범프포일베어링의 탄성유체윤활 특성 (Elasto-Hydrodynamic Lubrication Characteristics of Bump Foil Bearings)

  • 김영철;이동현;김경웅
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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    • pp.98-103
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    • 2004
  • This paper presents modeling and simulation of the bump foil bearings with consideration of the elastic behavior of the foil and gas compressibility. Heshmat had originally introduced the simple compliance model to estimate the EHL(elasto-hydrodynamic lubrication) performance. But this approach can not consider the deflection of top foil at the edge of bearing, so model is insufficient to analyze in case that the eccentricity ratio is greater than I. So the top foil is considered as a simple beam model supported by linear spring elements, and the bump foil deflection can be simple compliance model. The EHL calculations are performed for convention rigid type, classical foil type, variable pitch type and double bump type toil bearings. This paper presents that 2nd or 3rd generation bearings have excellent performance in every speeds.

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범프 마찰을 고려한 공기포일베어링의 성능해석 (Performance Analysis of Air Foil Bearings with Bump Friction)

  • 김영철;이동현;김경웅
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2005년도 연구개발 발표회 논문집
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    • pp.803-809
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    • 2005
  • This paper presents the theoretical model to investigate the effect of Coulomb damping in the sub-structure of a foil bearing. Foil deflection is restricted by friction of bumps. Equivalent viscous damping of the bump foils is derived from the Coulomb friction. Dynamic equation of the bumps is constituted by stiffness and damping terms. This point give the difference from Heshmat's frictionless and simple compliance bump model. The fluid is modeled with the compressible Reynolds equation. A perturbation approach is used to determine the static and dynamic performance of the bearing from the coupled fluid-structural model. The analysis result shows that the static and dynamic performance is enhanced by bump friction. This analysis technique would be extended to development of a high performance bearing.

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범프마찰을 고려한 공기포일베어링의 성능해석 (Performance Analysis of Air Foil Bearings with Bump Friction)

  • 김영철;이동현;김경웅
    • 한국유체기계학회 논문집
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    • 제9권1호
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    • pp.47-55
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    • 2006
  • This paper presents the theoretical model to investigate the effect of Coulomb damping in the sub-structure of a foil bearing. Foil deflection is restricted by friction of bumps. Equivalent viscous damping of the bump foils is derived from the Coulomb friction. Dynamic equation of the bumps is constituted by stiffness and damping terms. This point give the difference from Heshmat's frictionless and simple compliance bump model. The fluid is modeled with the compressible Reynolds equation. A perturbation approach is used to determine the static and dynamic performance of the bearing from the coupled fluid-structural model. The analysis result shows that the static and dynamic performance is enhanced by bump friction. This analysis technique would be extended to development of a high performance bearing.