• Title/Summary/Keyword: Finite Element (FE)

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Finite Element Analysis of Cylinder Head/Block Compound (엔진 실린더 헤드/블록의 유한 요소 해석)

  • Kim, Beom-Keun;Chang, Hoon
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.3
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    • pp.28-38
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    • 2003
  • Finite element analysis of cylinder heat/block compound under assembly, thermal and firing condition were performed. FE model including two cylinders with gasket, head bolts, liners and valve seats was used. FE modeling method and boundary conditions were introduced. Stress distribution and deformation of cylinder head and block under each loading condition were presented. Gasket pressure distribution and bore distortion level were predicted. Measured data of bore distortion was compared with the analysis results. The analysis result showed similar trends with the experimental data. High cycle fatigue analysis on the basis of this result has been performed in order to find the critical areas of the engine assembly.

A Finite Element Model for Bipolar Resistive Random Access Memory

  • Kim, Kwanyong;Lee, Kwangseok;Lee, Keun-Ho;Park, Young-Kwan;Choi, Woo Young
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.3
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    • pp.268-273
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    • 2014
  • The forming, reset and set operation of bipolar resistive random access memory (RRAM) have been predicted by using a finite element (FE) model which includes interface effects. To the best of our knowledge, our bipolar RRAM model is applicable to realistic cell structure optimization because our model is based on the FE method (FEM) unlike precedent models.

Characteristic features of concrete behaviour: Implications for the development of an engineering finite-element tool

  • Kotsovos, Michael D.;Pavlovic, Milija N.;Cotsovos, Demetrios M.
    • Computers and Concrete
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    • v.5 no.3
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    • pp.243-260
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    • 2008
  • The present article summarises the fundamental characteristics of concrete behaviour which underlie the formulation of an engineering finite element model capable of realistically predicting the behaviour of (plain or reinforced) concrete structural forms in a wide range of problems ranging from static to impact loading without the need of any kind of re-calibration. The already published evidence supporting the proposed formulation is complemented by four additional typical case studies presented herein; for each case, a comparative study is carried out between numerical predictions and the experimental data which reveals good agreement. Such evidence validates the material characteristics upon which the FE model's formulation is based and provides an alternative explanation regarding the behaviour of structural concrete and how it should be modelled which contradicts the presently (widely) accepted assumptions adopted in the majority of FE models used to predict the behaviour of concrete.

A study on the finite element modeling of femur based marching cube algorithm (Marching cube 알고리즘을 이용한 대퇴골의 유한요소 모델링에 관한 연구)

  • 곽명근;오택열;변창환;이은택;유용석
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.1074-1077
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    • 2002
  • Biomechanical behavior of the human femur is very important in various clinical situations. In this study, the data of FE models based on DICOM file exported from Computed tomography(CT). We generated FE models(voxel model, tetra model) of human femur using CT slide image. We compared them with Yon Mises stress results derived from finite element analysis(FEA). Comparing the two models, we found a correlation of them. As a result, the tetra model based proposed marching cube algorithm is a valid and accurate method to predict parameters of the complex biomechanical behavior of human femur.

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A Study on the Voxel Mesh Technique for Finite Element Modeling of Human Bone (인체 골(bone)의 유한요소 모델링을 위한 VOXEL MESH 기법에 관한 연구)

  • 변창환;오택열;백승민;채경덕
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.1081-1084
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    • 2002
  • In this study, we perform 3-D reconstruction of human proximal femur from DICOM files by using voxel mesh algorithm. After 3-D reconstruction, the model converted to Finite Element model which developed for automatically making not only 3-D geometrical model but also FE model from medical image dataset. During this job, trabecular pattern, one of characteristic of human bone can be added to the model by means of giving it's own elastic property calculated from intensity in CT scanned image to the each voxel. And then another model is made from same image dataset which have two material properties - one corresponds to cortical bone, another to trabecular bone. Finally, validity of voxel mesh technique is verified through comparing results of FE analysis, free vibration and stress analysis.

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FE-based On-Line Model for the Prediction of Roll Force and Roll Power in Finishing Mill (II) Effect of Tension (유한요소법에 기초한 박판에서의 압하력 및 압연동력 정밀 예측 On-Line모델 (II) 장력의 영향)

  • KWAK W. J.;KIM Y. H.;PARK H. D.;LEE J. H.;HWANG S. M.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2001.10a
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    • pp.121-124
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    • 2001
  • On-line prediction model which calculate roll force, roll power and forward slip of continuous hot strip rolling was built based on the results of plane strait rigid-viscoplastic finite element process model. Using the integrated FE process model, a series of finite element simulation was conducted over the process variables, and the influence of various process conditions on non-dimensional parameters was inspected. The prediction accuracy of the proposed on-line model under front and back tension is examined through comparison with predictions from a finite element process model over the various process conditions. In addition, we examined the validity of the on-line prediction model through comparison with roll force of experiment in hot rolling.

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Finite Element Analysis of Thermal Fatigue Safety for a Heavy-Duty Diesel Engine (대형디젤엔진의 열적 피로안전도 분석을 위한 유한요소해석)

  • 조남효;이상업;이상규;이상헌
    • Transactions of the Korean Society of Automotive Engineers
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    • v.12 no.1
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    • pp.122-129
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    • 2004
  • Finite element analysis was performed to analyze structural safety of a new heavy-duty direct injection diesel engine. A half section of the in-line 6-cylinder engine was selected as a computational domain. A mapping method was used to project heat transfer coefficients from CFD results of engine coolant flow onto the FE model. The accurate setting of thermal boundary condition on the FE model was expected to result in improved prediction of temperature, cylinder bore distortion, and stresses. Characteristics of high cycle fatigue were investigated by assuming the engine was operated under the following five loading conditions repeatedly; assembly force, assembly force with thermal loading, alternating maximum gas pressure loading at each cylinder combined with assembly force and thermal loading. Distribution of fatigue safety factor was calculated by using it Haigh diagram in which the maximum and the minimum stresses were selected from the five loading cases.

Updating of a Finite Element Model with Damping Effect Using Frequency Response Functions (주파수응답함수를 이용한 감쇠가 있는 유한요소모형의 개선)

  • Lee, Hyung-Seok;Woo, Sang-Yeon;Lee, Gun-Myung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.708-713
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    • 2000
  • Finite element analysis is frequently used to get dynamic characteristics of complex structures. Since the results often show differences from experimentally measured ones, updating of finite element models is performed to make the FE results agree with measured ones. Among several model updating methods, one is to use frequency response function data. This paper investigates characteristics of the model updating method using simulated and experimental data for a cantilever beam. Damping effect is included in FE models, and FRFs for rotational displacements are calculated from FRFs for translational displacements using interpolation.

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A quasi-static finite element approach for seismic analysis of tunnels considering tunnel excavation and P-waves

  • Zhao, Wusheng;Zhong, Kun;Chen, Weizhong;Xie, Peiyao
    • Earthquakes and Structures
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    • v.22 no.6
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    • pp.549-559
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    • 2022
  • The quasi-static finite element (FE) approaches are widely used for the seismic analysis of tunnels. However, the conventional quasi-static approaches may cause significant deviations when the tunnel excavation process is simulated prior to the quasi-static analysis. In addition, they cannot account for vertical excitations. Therefore, this paper first highlights the limitations of conventional approaches. A hybrid quasi-static FE approach is subsequently proposed and extensively validated for various conditions. The hybrid approach is simple and not time consuming, and it can be used for the preliminary seismic design of tunnels, especially when the tunnel excavation and vertically propagating P-waves are considered.

Analytical Equivalent Stiffness Analysis for Various Reinforcements of Wall-thinned Pipe (감육 배관의 다양한 보강 형태에 따른 이론적 등가 강성 검증)

  • Je-Hoon Jang;Ji-Su Kim;Yun-Jae Kim
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.18 no.1
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    • pp.11-18
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    • 2022
  • When wall-thinning in a pipe occurs during operation of nuclear power plant, reinforcement of the pipe needs to be performed. Accordingly, the structural response of the piping system due to introduction of the reinforcement may be re-evaluated. For elastic structural analysis of the piping system with the reinforced pipe using finite element (FE) analysis, the stiffness of the reinforced pipe is needed. In this study, the stiffness matrix of wall-thinned pipe with pad reinforcement or composite reinforcement is analytically derived. The validity of the proposed equations is checked by comparing with systematic finite element (FE) analysis results.