• 제목/요약/키워드: 평판진동

검색결과 428건 처리시간 0.022초

회전 외팔평판의 면외 방향 굽힘진동 해석 (Flapwise Bending Vibration Analysis of Rotating Cantilever Plates)

  • 김성균;유홍희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집A
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    • pp.613-618
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    • 2000
  • It is well known that the rotating motion of a blade-like structure induces centrifugal inertia force that causes the variation of the natural frequencies of the structure. Even though most of blade-like structures can be successfully Idealized as beams, some behave like plates rather than beams. This paper presents a modeling method for the flapwise bending vibration analysis of rotating cantilever plates. The dependence of natural frequencies and free vibration modes on the angular speed as well as the aspect ratio of a rotating plate is investigated. Particularly. the natural frequency loci crossing is observed and discussed In the present study.

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임의의 자세를 갖는 외팔평판의 진동해석 (Vibration Analysis of Rotating Cantilever Plates with Arbitrary Orientation Angle)

  • 김성균;유홍희
    • 대한기계학회논문집A
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    • 제27권8호
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    • pp.1331-1337
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    • 2003
  • Linearized equations of motion for the vibration analysis of rotating cantilever plates with arbitrary orientation angle are derived in the present work. Two in-plane stretch variables are introduced to be approximated. The use of the two in-plane stretch variables enables one to derive the equations of motion which include proper motion-induced stiffness variation terms. The equations of motion are transformed into dimensionless forms in which dimensionless parameters are identified. The effects of the dimensionless parameters on the modal characteristics of rotating cantilever plates are investigated through numerical study. The natural frequency loci veering along with the associated mode shape variations, which occur while the rotating speed increases, are also presented and discussed.

평판의 고정밀도 고유진동수 추출을 위한 개선된 MNDIF법 정식 개발 (New Formulation of MNDIF Method for Extracting Accurate Natural Frequencies of Plates)

  • 강상욱;윤주일
    • 한국소음진동공학회논문집
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    • 제23권8호
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    • pp.725-733
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    • 2013
  • An improved formulation of the MNDIF method is introduced to extract highly accurate natural frequencies of concave plates with arbitrary shape. Originally, the MNDIF method cannot yield accurate natural frequencies for concave plates. It can be applicable to only convex plates. To overcome this weak point, a new approach of dividing a concave plate into two convex domains and applying the MNDIF method to each domain is proposed and the validity and accuracy are shown in verification examples.

가속을 받는 사다리꼴 외팔 평판의 동특성 해석 (Dynamic Characteristic Analysis of Trapezoidal Cantilever Plates Undergoing Translational Acceleration)

  • 임홍석;유홍희
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 춘계학술대회논문집
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    • pp.268-273
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    • 2002
  • A modeling method for the dynamic characteristic analysis of a translationally accelerated trapezoidal cantilever plate is presented in this paper. The equations of motion for the plate are derived and transformed into a dimensionless form. The effects of the inclination angles and the acceleration on the vibration characteristics of the plate are investigated. Incidentally, natural frequency loci veering and associated mode shape variations are observed and discussed

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병진 가속도 운동을 하는 외팔평판의 진동해석 (Vibration Analysis of Cantilever Plates Undergoing Translationally Accelerated Motion)

  • 김성균;유홍희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집B
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    • pp.349-354
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    • 2001
  • A structure which is accelerated in the chordwise direction induces variation of the bending stiffness due to inertia force. Thus, the characteristic of natural vibration is also changed. This paper presents a modeling method for the vibration analysis of translationally accelerated cantilever plates. The dependence of natural frequencies and modes on the acceleration changes of the plate is investigated. Particularly, a natural frequency loci veering is observed and discussed in the present study.

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압전재료와 점탄성 재료를 이용한 평판 진동 음장의 능동제어 (Active Control of Sound Fields from Vibrating Plates Using Piezoelectric and Viscoelastic Material)

  • 강영규
    • 한국소음진동공학회논문집
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    • 제12권12호
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    • pp.950-955
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    • 2002
  • The coupled finite/boundary element method is used in numerical analysis for acoustic radiation from the vibration of rectangular composite plate which is simply supported. This analysis is validated using the Wallace equation for an isotropic plate. Active control of sound fields has been tarried out using 3 pairs of piezoelectric sensor/actuator and a pair of viscoelastic material by Passive constrained layer damping treatment. The results show that the optimal placement of piezoelectric sensor/actuator and VE patch is required to control the sound fields from a vibrating composite plate.

유체로 연성된 두 환형평판의 진동해석 (Vibration Analysis of Two Annular Plates Coupled with a Fluid)

  • 정경훈;김종인
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.906-910
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    • 2004
  • An analytical method for the free vibration of two annular plates coupled with water was developed by the Rayleigh-Ritz method. The two plates with unequal thickness are clamped along a rigid cylindrical vessel wall. It is assumed that the fluid bounded by a rigid cylindrical vessel is incompressible and non-viscous. The wet mode shape of the annular plates Is assumed as a combination of the dry mode shapes of the plates. The fluid motion is described by using the fluid displacement potential and determined by using the compatibility conditions along the fluid interface with the plate. Minimizing the Rayleigh quotient based on the energy conservation gives an eigenvalue problem. It is found that the theoretical results can predict well the fluid-coupled natural frequencies comparing with the finite element analysis result.

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