• 한국자동차공학회논문집
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• 제13권4호
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• pp.1-7
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• 2005

In vehicle door system, weatherstrip seals protect passengers form noise, dust, rain and wind out of the vehicle. The higher efficient a weatherstrip is, the more durable it is in contact between the door and body frame. In this study, nonlinear finite element(FE) analysis is performed to obtain cauchy-stresses, displacements and reaction forces of the weatherstrip. Mechanical properties of the weatherstrip is obtained by uniaxial tension test. The MARC which is a commercial software for the nonlinear analysis of a flexible FE model is used. Twenty-one cases of the FE model are developed by using Ogden-foam formulation. In the results of nonlinear FE analysis, the most valuable deformation of the weatherstrip occurred when displacement control value reaches 7.2mm. Severe deformation is observed as the displacement control value become more increased. When the weatherstrip is designed, it would be considered that the displacement value of the weatherstrip has to be less than 7.2mm.

• 한국분말재료학회지
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• 제6권1호
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• pp.56-61
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• 1999

The plastic deformation behaviors for powder extrusion of rapidly soildified Al-Si-Fe alloys at high temperature were investigated. During extrusion of Al-Si-Fe alloys, primary Si and intermetallic compound in matrix are broken finely. Additionally, during extrusion metastable $\delta$ phase($Al_4SiFe_2$) intermetallic compound disappears and the equilibrium $\beta$ phase($Al_5FeSi_2$) is formed. In gereral, it was diffcult to establish optimum process variables for extrusion condition through experimentation, because this was costly and time-consuming. In this paper, in order to overcome these problems, we compared the experimental results to the finite element analysis for extrusion behaviors of rapidly solidified Al-Si-Fe alloys. This ingormation is expected to assist in improving rapidly solidified Al-Si alloys extrusion operations.

• 한국압력기기공학회 논문집
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• 제18권1호
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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.

• Steel and Composite Structures
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• 제24권6호
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• pp.697-709
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• 2017

The current study addresses the local buckling analysis of an infinite thin rectangular symmetrically laminated composite plate restrained by a tensionless Winkler foundation and subjected to uniform in-plane shear loading. An analytic method (i.e., one-dimensional mathematical method) is used to achieve the analytical solution estimate of the contact buckling coefficient. In addition, to study the effect of ply angle and foundation stiffness on the critical buckling coefficients for the laminated composite plates, the parametric studies are implemented. Moreover, the convergence for finite element (FE) mesh is analysed, and then the examples in the parametric study are validated by the FE analysis. The results show that the FE analysis has a good agreement with the analytical solutions. Finally, an example with the analytical solution and FE analysis is presented to demonstrate the availability and feasibility of the presented analytical method.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.373-379
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• 2001

There is a big issue to generate 3D hexahedral finite element (FE) model, since a process to divide the whole domain into several simple-shaped sub-domains is required before generating a continuous mesh with mapped mesh generators. In general, it is nearly impossible to set up proper division numbers interactively to keep mesh connectivity between sub-domains on a complicated arbitrary-shaped domain. If mesh continuity between sub-domains is not required in an analysis, this complicated process can be omitted. Element-free Galerkin method (EFGM) can accept discontinuous meshes, which only requires nodal information. However it is difficult to choose a reasonable influenced domain in moving least squares scheme with non-uniformly distributed nodes in discontinuous FE models. A new FE scheme fur discontinuous mesh is proposed in this paper by applying improved EFGM with some modification to derive FE approximated function in discontinuous parts. Its validity is evaluated on linear elastic problems.

• 한국소음진동공학회논문집
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• 제18권9호
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• pp.972-981
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• 2008

The blower which is installed in a FCEV(fuel cell electric vehicle) may cause noise due to misalignment and unbalance of mechanical components that rotate at high speed. One of the key points in efforts to minimize the noise radiation from a blower is the knowledge of the main radiating component and the relation between the surface vibration of a blower and the sound pressure. In this research, the blower model is developed based on FEM(finite element method). FE(finite element) model is reliable by correlation of frequencies and MAC(modal assurance criterion) values between EMA(experimental modal analysis) and FEA(finite element analysis). This model is applied to predict the vibration of a blower by using inverse force identification method and predict the radiating noise by using BEM(boundary element method). Comparing the frequencies of resonance and those mode shapes between EMA and FEA, a structural modification of the FE model is evaluated for reducing the parameters of the blower noise.

• Journal of the Korean Data and Information Science Society
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• 제17권4호
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• pp.1299-1307
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• 2006

This study investigates solving production problems in an automotive stamping plant using Finite Element (FE) analysis. The fundamentals of stamping, metal plasticity and FE analysis are developed. In this paper, we provide the basis for a simulation of the stamping of a production part, the automotive rear floorpan. On-plant factorial Design of Experiments (DoE) were simulated using the floorpan model. The accuracy of the simulations was undetermined because of variability in the DoE results. Predictions of flange shape, wrinkling and thickness show qualitative agreement with manufactured parts and indicate that simulating an industrial part is feasible.

• 콘크리트학회논문집
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• 제25권5호
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• pp.529-537
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• 2013

이 연구의 목적은 하중기반 유한요소 정식화에 의한 FRP 보강된 철근콘크리트 보 또는 기둥 부재의 비선형 층상화의 등매개 골조 유한요소모델을 개발하는데 있다. 단면에서 콘크리트는 3축 응력-변형률 관계로 모델화하고 FRP 피복층은 2차원의 적층복합재료로 모델화하였다. 하중기반 유한요소의 요소강성행렬은 변위형상함수의 가정이 없고 하중보간함수를 갖고 있다. 횡 하중을 받는 GFRP 시트 보강된 철근콘크리트 기둥의 실험에 대해 개발된 하중기반 유한요소모델에 의한 해석을 수행하였다. 기존 강성도법의 유한요소해석과 비교하여 하중기반 유한요소해석은 전체적인 하중-변위 관계 뿐만 아니라 기둥의 소성힌지영역에서의 비선형 변형 및 손상을 보다 정확히 예측해 주었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.62-67
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• 2002

It has been shown that the vibrational response of a tire can be represented by a set of decaying waves, each associated with a particular cross-sectional mode shape in the region near the contact patch. Thus, it can be concluded that tires can be effectively modeled as lossy waveguides. It has also been shown that the sound radiation from tires is mainly from the region close to the contact patch. In consequence, it may be computationally efficient to analyze tire vibration and sound radiation in the region close to the contact patch by using a hybrid finite element model in which the cross-section of a tire is approximated by 2-D finite elements while an analytical wave solution is assumed in the circumferential direction of the tire. In this article. a hybrid finite element was formulated based on a composite shell model. The dispersion relations for sample structures obtained by using the hybrid FE model were then compared with those obtained by using a full, three-dimensional FE model. It has been shown that the FE analysis made using the hybrid 2-D finite elements yields results in close agreement with the three-dimensional model.

• Steel and Composite Structures
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• 제34권1호
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• pp.35-51
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• 2020

Integral abutment bridges (IABs) are those bridges without expansion joints. A single row of steel H-piles (SHPs) is commonly used at the thin and stub abutments of IABs to form a flexible support system at the bridge ends to accommodate thermal-induced displacement of the bridge. Consequently, as the IAB expands and contracts due to temperature variations, the SHPs supporting the abutments are subjected to cyclic lateral (longitudinal) displacements, which may eventually lead to low-cycle fatigue (LCF) failure of the piles. In this paper, the potential of using finite element (FE) modeling techniques to estimate the LCF life of SHPs commonly used in IABs is investigated. For this purpose, first, experimental tests are conducted on several SHP specimens to determine their LCF life under thermal-induced cyclic flexural strains. In the experimental tests, the specimens are subjected to longitudinal displacements (or flexural strain cycles) with various amplitudes in the absence and presence of a typical axial load. Next, nonlinear FE models of the tested SHP specimens are developed using the computer program ANSYS to investigate the possibility of using such numerical models to predict the LCF life of SHPs commonly used in IABs. The comparison of FE analysis results with the experimental test results revealed that the FE analysis results are in close agreement with the experimental test results. Thus, FE modeling techniques similar to that used in this research study may be used to predict the LCF life of SHP commonly used in IABs.