FINITE-ELEMENT ANALYSIS OF TWO METER DROP OF DEFENSE HIGH-LEVEL WASTE PACKAGE

ALBA synchrotron light facility includes a 3 GeV low-emittance storage ring capable of running in the top-up mode which will feed a number of beamlines. Xaloc and CIRCE are among these beamlines. These beamlines are equipped with mirrors which need high stability. There are a lot of mirror chambers in the market and we decided to improve one of them rather than developing a new one. For this purpose, the ALBA team organized a collaboration with a supplier of beamline components. ALBA did the conceptual design of the improvements, the Finite Element Analysis (FEA) optimization and the metrology tests. The supplier provided a detailed design and the production. The improvement was implemented on several mirror chambers including actuators from two to five degrees of freedom. At the beginning of the project, the hypothesis was an excitation coming from the ground lower than 1 µm for frequencies below 45 Hz and negligible above it. The strategy[0] in terms of dynamical stability was not to amplify the ground excitation below 45 Hz or around 50 Hz. That is, to increase the frequency of the system resonances above 45 Hz (excluding the range of about 50 Hz). As a result, we obtained a high level of stability for such mirror systems and we almost met the target value for the first mode of vibration.

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Influence of Phase-Change Materials and Additional Layer on Performance of Lateral Phase-Change Memories

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.497.106 ◽

2011 ◽

Vol 497 ◽

pp. 106-110

Author(s):

You Yin ◽

Sumio Hosaka

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Phase Change ◽

Phase Change Materials ◽

Electrical Characterization ◽

Element Analysis ◽

Additional Layer ◽

Thermal Confinement ◽

High Power Consumption ◽

High Level

Performance of lateral phase change memories (LPCMs) is investigated by both electrical characterization and finite element analysis. Ge2Sb2Te5 lateral PCMs (GST-LPCMs) exhibit a low reset current but a bad endurance. By replacing GST with Sb2Te3 (ST) and adding a TiN layer between ST and electrodes, the ST-TiN-LPCMs are demonstrated to have a much improved endurance. Finite element analysis of the LPCMs with electric-thermal structural interaction shows that thermal confinement makes GST-LPCMs low-power consumptive but that high level stress makes them readily broken. In contrast, ST-TiN-LPCMs experience low level stress during operation but high power consumption is required.

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Modal and Stress Analysis of Cellular Structures Produced with Additive Manufacturing by Finite Element Analysis (FEA)

Academic Perspective Procedia ◽

10.33793/acperpro.01.01.52 ◽

2018 ◽

Vol 1 (1) ◽

pp. 263-272

Author(s):

Bekir Yalçın ◽

Berkay Ergene ◽

Uçan Karakılınç

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Topology Optimization ◽

Additive Manufacturing ◽

Honeycomb Structure ◽

Cellular Structures ◽

Aircraft Industry ◽

Element Analysis ◽

Manufacturing Methods ◽

High Level

Cellular structures such as regular/irregular honeycombs and re-entrants are known as lighter, high level flexibility and more efficient materials; these cellular structures have been mainly designed with topology optimization and obtained with new additive manufacturing methods for aircraft industry, automotive, medical, sports and leisure sectors. For this aim, the effect of cellular structures such as the honeycomb and re-entrant on vibration and stress-strain behaviors were determined under compression and vibration condition by finite elements analyses (FEA). In FEA, the re-entrant and honeycomb structures were modeled firstly and then the stress and displacement values for each structure were obtained. Secondly, vibration behaviors of these foam structures were estimated under determined boundary conditions. In conclusion, the effect of topology in foam structures on vibration and mechanical behaviour were exhibited in FEA results. The obtained stress results of FEA show that all stresses (?x, ?y, ?vm, ?xy) are lower on honeycomb structure than reentrant structure. Besides, natural frequency values (?1, ?2, ?3) and appearance of each structure were observed by using FEA.

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A Topological Model for the Representation of Meshing Constraints in the Context of Finite Element Analysis

Volume 3: 26th Computers and Information in Engineering Conference ◽

10.1115/detc2006-99280 ◽

2006 ◽

Cited By ~ 1

Author(s):

Gilles Foucault ◽

Jean-Claude Le´on ◽

Jean-Christophe Cuillie`re ◽

Vincent Franc¸ois ◽

Roland Maranzana

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Computer Aided Design ◽

Boundary Representation ◽

Fe Model ◽

Element Analysis ◽

Element Size ◽

Cad Models ◽

High Level ◽

Meshing Process

The preparation of Finite Element analysis models (FE models) from Computer Aided Design (CAD) models is still a difficult task since its Boundary Representation (B-Rep) is often composed of a large number of thin faces, small edges, which are much smaller than the desired element size, and are not relevant for the meshing process. Such inconsistencies often cause poor-shaped FE elements, overdensities of elements, not only slowing down the computation of the FE solution, but also producing poor simulation results. In this paper, we present a “Mesh Constraint Topology” (MCT) model with adaptation operators aiming at transforming the CAD model in a FE model which only contains meshing-relevant edges and vertices, i.e. the explicit model of data intrinsic to the meshing process. Because the topology of faces adapted for meshing could contain interior edges, the MCT is represented with adjacency graphs instead of the B-Rep data-structure. We demonstrate how graphs provide efficient schemes to qualify interior and boundary entities, and facilitate the design of adaptation operators using high-level graph operators. Application and results are presented through adaptation issues of CAD models solved using MCT adaptation operators.

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Application of Elastic-Plastic Finite Element Analysis to Determine the Ultimate Load of Components

Volume 2: Computer Technology and Bolted Joints ◽

10.1115/pvp2015-45886 ◽

2015 ◽

Author(s):

Wolf Reinhardt

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Ultimate Load ◽

Plastic Instability ◽

Plastic Behavior ◽

Element Analysis ◽

Section Viii ◽

Load Analysis ◽

High Level ◽

Service Standards

An assessment of pressure retaining components based on ultimate load (or plastic instability load) is used in Section VIII Div. 2 and Section III Appendix F of the ASME Boiler and Pressure Vessel Code, as well as in various fitness-for-service standards and guidelines. The ultimate load analysis strives for a realistic prediction of the plastic behavior of a component up to the highest load or load combination that the component can support. The high level of applied load may cause significant deformations in the component, and for an accurate assessment the analysis must consider the effect of these deformations on the material as well as on equilibrium and the state of stress. This paper discusses briefly the basis of ultimate load analysis and considerations in performing such analysis with finite element analysis. The main focus is to validate the analysis approach by demonstrating close agreement between finite element analysis and analytical solutions and the results of component tests.

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