Verification of Submodeling for the Finite Element Analysis of Stress Concentrations

2019 ◽  
Vol 4 (3) ◽  
Author(s):  
A. A. Kardak ◽  
G. B. Sinclair
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Stress Concentrator ◽  
Test Problems ◽  
Stress Concentrations ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Solution Verification ◽  
Focus Analysis

Abstract Submodeling enables finite element engineers to focus analysis on the subregion containing the stress concentrator of interest with consequent computational savings. Such benefits are only really gained if the boundary conditions on the edges of the subregion that are drawn from an initial global finite element analysis (FEA) are verified to have been captured sufficiently accurately. Here, we offer a two-pronged approach aimed at realizing such solution verification. The first element of this approach is an improved means of assessing the error induced by submodel boundary conditions. The second element is a systematic sizing of the submodel region so that boundary-condition errors become acceptable. The resulting submodel procedure is demonstrated on a series of two-dimensional (2D) configurations with significant stress concentrations: four test problems and one application. For the test problems, the assessment means are uniformly successful in determining when submodel boundary conditions are accurate and when they are not. When, at first, they are not, the sizing approach is also consistently successful in enlarging submodel regions until submodel boundary conditions do become sufficiently accurate.

Practical Procedures for Technical and Economic Investigation of Ship Structural Details

1981 ◽  
Vol 18 (01) ◽  
pp. 51-68
Author(s):  
Donald Liu ◽  
Abram Bakker
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentrations ◽  
Element Analysis ◽  
Analysis Techniques ◽  
Structural Problems ◽  
Analysis Technique ◽  
The Finite Element Analysis ◽  
Structural Details

Local structural problems in ships are generally the result of stress concentrations in structural details. The intent of this paper is to show that costly repairs and lay-up time of a vessel can often be prevented, if these problem areas are recognized and investigated in the design stages. Such investigations can be performed for minimal labor and computer costs by using finite-element analysis techniques. Practical procedures for analyzing structural details are presented, including discussions of the results and the analysis costs expended. It is shown that the application of the finite-element analysis technique can be economically employed in the investigation of structural details.

Variational Formulations for the Finite Element Analysis of Noise Radiation from High-Speed Machinery

1981 ◽  
Vol 103 (4) ◽  
pp. 385-391 ◽  
Author(s):  
B. S. Thompson
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
High Speed ◽  
Acoustic Medium ◽  
Field Equations ◽  
Element Analysis ◽  
Vibrational Response ◽  
The Finite Element Analysis ◽  
Structural Interface

Variational theorems are presented for analyzing the vibrational response of flexible linkage mechanisms and the surrounding acoustic medium in which they are immersed. These theorems are established by generalizing Hamilton’s principle through using Lagrange multipliers to incorporate field equations and boundary conditions within the functional. The same philosophy is adopted to handle the conditions at the fluid-structural interface. When independent arbitrary variations of the system parameters are permitted, these acousto-elastodynamic theorems yield as characteristic equations the equation of motion for each member of the linkage, the acoustical wave equation, the compatibility conditions at the interface between the fluid and solid continua, and also the boundary conditions. These variational statements provide the foundations for several different classes of finite element analysis.

Finite element analysis for precision cold forging of helical gear using recurrent boundary conditions

1998 ◽  
Vol 212 (3) ◽  
pp. 231-240 ◽  
Author(s):  
Y B Park ◽  
D Y Yang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Three Dimensional ◽  
Helical Gear ◽  
Cold Forging ◽  
Rigid Plastic ◽  
Element Analysis ◽  
The Finite Element Analysis ◽  
Good Agreement

In metal forming, there are problems with recurrent geometric characteristics without explicitly prescribed boundary conditions. In such problems, so-called recurrent boundary conditions must be introduced. In this paper, as a practical application of the proposed method, the precision cold forging of a helical gear (which is industrially useful and geometrically complicated) has been simulated by a three-dimensional rigid-plastic finite element method and compared with the experiment. The application of recurrent boundary conditions to helical gear forging analysis is proved to be effective and valid. The three-dimensional deformed pattern by the finite element analysis is shown, and the forging load is compared with the experimental load. The profiles of the free surface of the workpiece show good agreement between the computation and the experiment.

scholarly journals Computational consistency of the material models and boundary conditions for finite element analyses on cantilever beams

2018 ◽  
Vol 10 (6) ◽  
pp. 168781401878002 ◽  
Author(s):  
Wei-chen Lee ◽  
Chen-hao Zhang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Material Model ◽  
Cantilever Beams ◽  
Element Analysis ◽  
Material Models ◽  
The Finite Element Analysis ◽  
Selection Of ◽  
Good Agreement

The objective of this research was to investigate the effects of material models, element types, and boundary conditions on the consistency of finite element analysis. Two cantilever beams were used; one made of stainless steel SUS301 3/4H and the other made of polymer polyoxymethylene. The load–deflection curves of the two cantilever beams obtained by experiments were compared to those obtained by finite element analysis, where the material models—including bilinear, trilinear, and multi-linear—were used. Four element types—beam, plane stress, shell, and solid—were also employed with the material models to obtain the simulated load–deflection curves of the cantilever beams. It was found that bilinear material models had the stiffest behavior due to their overestimated yield strength. In addition, by applying a finite displacement to simulate the grip of the cantilever beams, the discrepancy between the simulated permanent set and the experimental set could be reduced from 80% to 5%. To sum up, both the selection of the material model and the setup of the boundary conditions are critical for obtaining good agreement between the finite element analysis results and the experimental data.

Finite Element Analysis of Thin Rectangular Plate Subjected to Uniformly Distributed Transverse Load: A Java Application

2015 ◽  
Vol 15 ◽  
pp. 107-122
Author(s):  
Amadou Adamou ◽  
Olisaemeka Osadebe
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Programming Language ◽  
Computer Application ◽  
Transverse Load ◽  
Element Analysis ◽  
Java Programming Language ◽  
Java Programming ◽  
The Finite Element Analysis

The present work developed a computer application for the finite element analysis of thin rectangular plates under uniformly distributed transverse load. The software, which was developed using Java programming language, is very user-friendly and flexible in the choice of the boundary conditions and mesh size. The choice of Java programming language was guided by its high memory management, which, in turn had a positive effect on the software runtime. The finite element analysis of a Kirchhoff isotropic plate under a uniformly distributed transverse load was carried out using the software. The results obtained agreed accurately with solutions available in literature. Error analysis conducted on the results confirmed that accuracy generally increases with an increase in the number of elements used in the discretization process. Specifically, for a 16 x 16 discretization, an accuracy ranging from 98.41 to 100 percent, and 95.83 to 100 percent was achieved for the five sets of boundary conditions handled, for deflections at the plate’s center and bending moments respectively.

On the Generation of Tuned Test Problems for Stress Concentrations

2021 ◽  
Author(s):  
Glenn Sinclair ◽  
Ajay A Kardak
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Stress Concentration ◽  
Precise Determination ◽  
Test Problems ◽  
Stress Concentrations ◽  
Element Analysis ◽  
Concentration Factors ◽  
Stress Concentration Factors

Abstract When stress concentration factors are not available in handbooks, finite element analysis has become the predominant method for determining their values. For such determinations, there is a need to know if they have sufficient accuracy. Tuned Test Problems can provide a way of assessing the accuracy of stress concentration factors found with finite elements. Here we offer a means of constructing such test problems for stress concentrations within boundaries that have local constant radii of curvature. These problems are tuned to their originating applications by sharing the same global geometries and having slightly higher peak stresses. They also have exact solutions, thereby enabling a precise determination of the errors incurred in their finite element analysis.

Experimental Modal Analysis of Appropriate Boundary Conditions for the Evaluation of Cross-Laminated Timber Panels for an In-Line Approach

2021 ◽  
Vol 71 (2) ◽  
pp. 161-170
Author(s):  
Adam Faircloth ◽  
Loic Brancheriau ◽  
Hassan Karampour ◽  
Stephen So ◽  
Henri Bailleres ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Boundary Conditions ◽  
Modal Analysis ◽  
Experimental Testing ◽  
Critical Role ◽  
Element Analysis ◽  
Cross Laminated Timber ◽  
Simply Supported ◽  
The Finite Element Analysis

Abstract Transverse modal analysis of timber panels is a proven effective alternative method for approximating a material's elastic constants. Specific testing configurations, such as boundary conditions (BC) and location of sensor and impact, play a critical role in the accuracy of the results obtained from the experimental assessment. This article investigates signal-specific details, such as the signal quality factor, that directly relate to the damping properties and internal friction as well as frequency shifting obtained from six different BCs. A freely supported (FFFF), opposing minor sides (shorter length) simply supported, and major sides (longest length) free (SFSF), as well as the reverse of the SFSF configuration with minor sides free and major lengths simply supported (FSFS) and all sides simply supported (SSSS) setup, are investigated. Variations into the proposed methods used to achieve an FFFF supported system are also considered. A combination of experimental testing in parallel with finite element analysis was conducted to re-create the setup that would be used within a manufacturing facility for nondestructive assessment of full-size cross-laminated timber panels. The differences between all BC configurations for their resonance frequency quality and location indicate that a freely supported system provides higher-resolution results, good comparison of less than 10 percent error with the finite element analysis and experimental results, and advantages in a simple experimental setup for the intended application.

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