• Title/Summary/Keyword: Infinite body

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Asymptotic analysis of ignition of a semi-infinite body for a large activation energy (활성화 에너지가 매우 큰 경우에 점근법을 이용한 반무한체의 점화에 관한 연구)

  • 백승욱
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.4
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    • pp.703-707
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    • 1989
  • The ignition of solid particle under strong convective heating has been investigated by applying an asymptotic analysis to a semi-infinite body for varying values of gas recovery temperature and convective heat transfer coefficient. It was found that if the scale of the reaction zone is much smaller than the characteristic length of the body size, then infinite body theory can be used to estimate the ignition delay time. Furthermore, the convective heat transfer coefficient was found to have more influence on predicting the ignition delay times of particle exposed to an incident shock wave rather than the gas recovery temperature.

Vibration of elastic and viscoelastic multilayered spaces

  • Karasudhi, P.;Liu, Y.C.
    • Structural Engineering and Mechanics
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    • v.1 no.1
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    • pp.103-118
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    • 1993
  • The near field is discretized into finite elements, and the far field into infinite elements. Closed form far-field solutions to three fundamental problems are used as the shape functions of the infinite elements. Such infinite elements are capable of transmitting all surface and body waves. An efficient scheme to integrate numerically the stiffness and mass matrices of these elements in presented. Results agree closely with those obtained by others.

The stress field in the body by tangential loading of a rectangular patch on a semi-infinite solid (반 무한체 위의 사각조각 면에 작용하는 접선하중에 의한 반 무한체내의 응력 해석)

  • 이문주;조용주
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1999.06a
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    • pp.20-29
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    • 1999
  • The stress field in the body by tangential loading of a rectangular patch on a semi-infinite solid has been solved analytically using Boussinesque's potential function. Its validity was proved by saint-venant's principle in remote region of the and in the vicinity of the surface with superposition of point loads.

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The Stress Field in a Body Caused by the Tangential Force of a Rectangular Patch on a Semi-Infinite Solid

  • Cho, Yong-Joo;Kim, Tae-Wan;Lee, Mun-Ju
    • KSTLE International Journal
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    • v.2 no.1
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    • pp.29-34
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    • 2001
  • The stress field in a body caused by the tangential loading of a rectangular patch on a semi-infinite solid has been solved analytically using a potential function. The validity of the results of this study was preyed by Saint-Venant's principle in the remote region and by the superposition of point loads in the vicinity of the surface.

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Solution for a semi-infinite plate with radial crack and radial crack emanating from circular hole under bi-axial loading by body force method

  • Manjunath, B.S.;Ramakrishna, D.S.
    • Interaction and multiscale mechanics
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    • v.2 no.2
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    • pp.177-187
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    • 2009
  • Machine or structural members subjected to fatigue loading will have a crack initiated during early part of their life. Therefore analysis of members with cracks and other discontinuities is very important. Finite element method has enjoyed widespread use in engineering, but it is not convenient for crack problems as the region very close to crack tip is to be discretized with very fine mesh. However, as the body force method (BFM), requires only the boundary of the discontinuity (crack or hole) to be discretized it is easy versatile technique to analyze such problems. In the present work fundamental solution for concentrated load x + iy acting in the semi-infinite plate at an arbitrary point $z_0=x_0+iy_0$ is considered. These fundamental solutions are in complex form ${\phi}(z)$ and ${\psi}(z)$ (England 1971). These potentials are known as Melan potentials (Ramakrishna 1994). A crack in the semi-infinite plate as shown in Fig. 1 is considered. This crack is divided into number of divisions. By applying pair of body forces on a division, the resultant forces on the remaining 'N'divisions are to be found for which ${\phi}_1(z)$ and ${\psi}_1(z)$ are derived. Body force method is applied to calculate stress intensity factor for crack in semi-infinite plate. Also for the case of crack emanating from circular hole in semi-infinite plate radial stress, hoop stress and shear stress are calculated around the hole and crack. Convergent results are obtained by body force method. These results are compared with FEM results.

A Study for Estimation of the Surface Temperature Rise Using the FVM and Semi-Infinite Solid Analysis (FVM과 반무한체 해석을 이용한 표면온도예측에 관한 연구)

  • 김태완;이상돈;조용주
    • Tribology and Lubricants
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    • v.18 no.6
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    • pp.389-395
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    • 2002
  • The surface temperature at the interface of bodies in a sliding contact is one of the most important factors influencing the behavior of machine components. The calculation of the surface temperature at a sliding contact interface has been an interesting and important subject for tribologist. Temperature analyses were usually performed under the consideration contacted two bodies as semi-infinite. But the analysis was difficulty in being applied to finite body and considering the boundary condition. In this study, contact temperature rise of two finite bodies and surfaces due to frictional heating under the rectangular and the circular sliding contact is calculated. Heat partition factor is calculated using semi-infinite solid analysis and the temperature of the finite bodies is calculated using FVM. It will be shown that Most frictional heat in the fore part of contact region for sliding direction is conducted into body that has a moving heat source and the site of the maximum temperature rise moves to the opposite direction of sliding during sliding.

Development of an Infinite Element for Impact Problem using ABAQUS UEL (ABAQUS UEL을 이용한 충돌 문제의 무한체요소 개발)

  • Yang, Seung-Yong;Goo, Byeong-Choon
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.2
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    • pp.58-64
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    • 2005
  • An infinite element for impact problem has been developed using ABAQUS/Standard UEL. 4-node plane strain element was considered, and the constitutive equation was derived from properties of propagation plane body waves. The element acts as unbounded domain to the plane waves generated by impact. The numerical method was tested for the simulation of plate impact. The results show the effectiveness of the infinite element.

Analysis of Arbitrarily Shaped Three Dimensional Cracks in an Infinite Body Using the FEAM (유한요소 교호법을 이용한 무한 물체에 존재하는 임의 형상의 삼차원 균열 해석)

  • Kim, Tae-Soon;Park, Jai-Hak;Park, Chi-Yong
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.278-283
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    • 2004
  • Many analysis methods, including finite element method, have been suggested and used for assessing the integrity of cracked structures. In the paper, in order to analyze arbitrarily shaped three dimensional cracks in an infinite body, the finite element alternating method is extended. The cracks are modeled as a distribution of displacement discontinuities by the displacement discontinuity method and the symmetric Galerkin boundary element method. Applied the proposed method to several example problems for planner cracks in finite bodies, the accuracy and efficiency of the method were demonstrated.

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Propagation Characteristics of a Surface Crack on a Semi-Infinite Body Due to Frictional Heating (마찰열에 의한 반무한체 표면균열의 전파특성)

  • Park, Jun-Ho;Park, Eun-Ho;Kim, Chae-Ho;Kim, Seock-Sam
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.10
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    • pp.3126-3134
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    • 1996
  • In this paper, to examine the propagation of inclined surface crack due to frictional heating, analytic model is considered as the semi-infinite elastic body subjected to the thermo-mechanical loading of an asperity moving with a high speed. Considering the moving of frictional heat source and convection on a semi-infinite surface having inclined crack, theoretical analysis was carried out to estimate the propagation characteristics of thermo-mechanical crack. Numerical results showed that stress intensity factor $K_\prod/P_0\sqrt{c}$ is increasing with increasing velocity and frictional coefficient, inclined degree, decreasing crack length and the maximum value of it is positioned at the trailing edge. So it is shown that the propagation probability of surface crack is high at the trailing edge of contact area as increasing velocity and frictional coefficient, inclined degree, as decreasing crack length.

Study of flat punch indentation to semi-infinite body with lpartially constrained free surface by moire method (구속표면을 가지는 반무한체에 대한 평저펀치의 압입의 연구)

  • ;Kim, Dong Won
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.3 no.4
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    • pp.164-172
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    • 1979
  • Experimental and numerical results concerning the flat punch indentation to semi-infinite body with partially constrained free surface are presented The distributions of slip line directions are predicted by Moire fringe analysis using Vinckier's method. A mumerical study is made of the same problem by finite element method and the results are compared with the experimental results. It is shown that the contour feature of possible slip line field is similar to that of well-known Prandtl indentation sloution.