• Title/Summary/Keyword: 미분변환법

Search Result 65, Processing Time 0.024 seconds

Vibration Analysis for Circular Arches with Variable Cross-section by using Differential Transformation and Generalized Differential Quadrature (미분변환법과 일반화 미분구적법을 이용한 가변단면 원호 아치의 진동 해석)

  • Shin, Young Jae;Kwon, Kyung Mun;Yun, Jong Hak;Yoo, Yeong Chan;Lee, Ju Hyung
    • Journal of Korean Society of Steel Construction
    • /
    • v.16 no.1 s.68
    • /
    • pp.81-89
    • /
    • 2004
  • The vibration analysis of the circular arch as a member of a structure has been an important subject of mechanics due to its various applications to many industrial fields. In particular, circular arches with variable cross section are widely used to optimize the distribution of weight and strength and to satisfy special architectural and functional requirements. The Generalized Differential Quadrature Method (GDQM) and Differential Transformation Method (DTM) were recently proposed by Shu and Zou, respectively. In this study, GDQM and DTM were applied to the vibration analysis of circular arches with variable cross section. The governing equations of motion for circular arches with variable cross section were derived. The concepts of Differential Transformation and Generalized Differential Quadrature were briefly introduced. The non-dimensionless natural frequencies of circular arches with variable cross section were obtained for various boundary conditions. The results obtained using these methods were compared with those of previous works. GDQM and DTM showed fast convergence, accuracy, efficiency, and validity in solving the vibration problem of circular arches with variable cross section.

Error Analysis of Approximate Solution by Differential Transform Method with respect to Non-linearity of Duffing Equation (미분변환법을 이용해 구해진 Duffing Equation 근사해의 비선형성 증가에 따른 오차 분석)

  • Yang, Seong-Uk;Kim, Dong-Hun;Kim, Bong-Gyun;Yang, Jun-Mo;Lee, Sang-Cheol
    • 한국항공운항학회:학술대회논문집
    • /
    • 2015.11a
    • /
    • pp.20-24
    • /
    • 2015
  • 미분변환법은 미분방정식의 해를 구하기 위한 방법으로 다양한 분야에서 적용에 관한 연구를 수행 중이다. 항공우주분야의 동역학 모델링의 경우 미분방정식은 비선형성을 포함하게 되며 일반적으로 수치해석을 이용해 근사해를 구하게 된다. 본 논문에서는 미분변환법을 이용해 구해진 근사해의 오차 추이를 분석한 내용을 다루고 있다. 이를 위한 예제로써 duffing equation을 사용하였으며, duffing equation에 포함된 비선형성을 증가시킴에 따라 미분변환법을 이용해 구한 근사해와 수치해석을 이용해 구한 수치해를 비교하였다.

  • PDF

미분변환법에 의한 탄성 지반상의 열림 균열을 가진 Euler-Bernoulli보의 진동 해석

  • 황기섭;윤종학;유영찬;신영재
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2003.11a
    • /
    • pp.690-695
    • /
    • 2003
  • The main purpose of this paper is to apply differential transformation method to vibration analysis of Euler-Bernoulli beam with open cracks on elastic foundation. The governing equation of motion of beam with open cracks on elastic foundation is derived. The concept of differential transformation is briefly introduced. The cracks are modeled by massless substitute spring. The effects of the crack location, size and the foundation constants, on the natural frequencies of the beam, are investigated.

  • PDF

Vibration Analysis of Circular Plate with Continuously Varying Thickness (가변두께를 가지는 원판의 진동해석에 관한 연구)

  • Shin, Young Jae;Jaun, Su Ju;Yun, Jong Hak;Yoo, Yeong Chan
    • Journal of Korean Society of Steel Construction
    • /
    • v.18 no.1
    • /
    • pp.1-10
    • /
    • 2006
  • paper presents the results of the use of the differential transformation technique in analyzing the free vibration of circular plates.calculations were carried out and were compared with previously published results. The results that were obtained when this method was used coincide with the results of The present analysis shows the usefulness and validity of differential transformation in solving a solid-circular and annular-plate problem in terms of free-vibration responses.

Vibration Analysis of Euler-Bernoulli Beam with Open Cracks on Elastic foundations Using Differential Transformation Method and Generalized Differential Quadrature Method (미분변환법과 일반화 미분구적법을 이용한 탄성 지반상의 열림 균열을 가진 Euler-Bernoulli 보의 진동 해석)

  • Hwang Ki-Sup;Yun Jong-Hak;Shin Young-Jae
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.30 no.3 s.246
    • /
    • pp.279-286
    • /
    • 2006
  • The main purpose of this paper is to apply differential transformation method(DTM) and generalized differential quadrature method(GDQM) to vibration analysis of Euler-Bernoulli beam with open cracks on elastic foundation. In this paper the concepts of DTM and GDQM were briefly introduced. The governing equation of motion of the beam with open cracks on elastic foundation is derived. The cracks are modeled by massless substitute spring. The effects of the crack location, size and the foundation constants, on the natural frequencies of the beam, are investigated. Numerical calculations are carried out and compared with previous published results.

Post-Buckling of Shear Deformable Uniform Columns Under a Combined Load (조합하중을 받는 전단변형 기둥의 좌굴 후 거동 해석)

  • Yoo, Yeong Chan;Shin, Young Jae
    • Journal of Korean Society of Steel Construction
    • /
    • v.15 no.3
    • /
    • pp.313-320
    • /
    • 2003
  • The governing equation of the post-buckling of shear-deformable uniform columns under a combined load consisting of a uniformly distributed axial load and a concentrated load at a free end was derived and the post-buckling analysis was investigated by using differential transformation. The loads were obtained for various end-slopes. The results obtained by the present method agree well with published results. In this paper, the differential transformation method was illustrated through its application to the non-linear differential equation of the post-buckling. It is expected that applications of the method to more challenging problems will are expected follow in future to ensue.

Analysis of Beam Resting on Hyperbolic Winkler Elastic Foundation by Differential Transformation (미분 변환법에 의한 쌍곡선형태 Winkler 탄성 지반상의 보 해석)

  • Shin, Yung-Jae;Yun, Jong-Hak;Jaun, Su-Ju
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2002.11b
    • /
    • pp.1060-1065
    • /
    • 2002
  • In this paper, the numerical analysis of beam rest ing on hyperbolic Winkler elastic foundation by differential transformation is performed. Accordig to the change of parameter of hyperbolic Winkler elastic foundation, beam deformation is computed when the boundary conditions are clamped-clamped, pined-pined and clamped-free.

  • PDF

Vibration Analysis of Non-homogeneous Damped Beam Using the Differential Transformation Method (미분변환법에 의한 비균질 감쇠보의 진동 해석)

  • Shin, Young-Jae;Jaun, Su-Ju;Yun, Jong-Hak
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.13 no.5
    • /
    • pp.1-6
    • /
    • 2005
  • In this paper, the natural frequencies of non-homogeneous damped beam are determined by using the differential transformation. The beam considered has different stiffness, damping and mass properties in each of two parts. The various boundary conditions are assumed at each end. The results obtained by the present method agree very well with those reported in the previous works. The present analysis shows the usefulness and validity of differential transformation in solving a non-homogeneous damped beam problem.

The Effect of Series Center on the Convergence of the Solution in Vibration Analysis by Differential Transformation Method(DTM) (미분변환법에 의한 진동 해석시 급수중심이 해의 수렴에 미치는 영향)

  • Shin, Young-Jae;Yun, Jong-Hak;Yoo, Yeong-Chan
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.31 no.2 s.257
    • /
    • pp.231-236
    • /
    • 2007
  • This paper presents the effect of the center of the series on convergence in solving vibration problems by Differential Transformation Method(DTM) to the transverse vibration of the Euler-Bernoulli beam under varying axial force. The governing differential equation of the transverse vibration of the Euler-Bernoulli beam under varying axial force is derived. The concepts of DTM were briefly introduced. Numerical calculations are carried out and compared with previously published results. The effect of the center of the series on convergence in solving the problem by DTM is discussed.