Analytic Methods for Stress Analysis of Two-Dimensional Flat Anisotropic Plates With Notches: An Overview

2014 ◽  
Vol 66 (6) ◽  
Author(s):  
R. D. B. Sevenois ◽  
S. Koussios

The anisotropy of composite plates often poses difficulties for stress field analysis in the presence of notches. The most common methods for these analyses are: (i) analytical means (AM), (ii) finite element analysis (FEA), and (iii) semi-analytical means (SAM). In industry, FEA has been especially popular for the determination of stresses in small to medium size parts but can require a considerable amount of computing power and time. For faster analyses, one can use AM. The available solutions for a given problem, however, can be quite limited. Additionally, AM implemented in commercial computer software are scarce and difficult to find. Due to this, these methods are not widespread and SAM were proposed. SAM combine the (easy) implementation of complex problems from FEA and the computational efficiency from AM to reduce the difficulty on mathematical operation and increase computational speed with respect to FEA. AM, however, are still the fastest and most accurate way to determine the stress field in a given problem. Complex problems, however, e.g., finite width plates with multiple loaded/unloaded notches, require a significant amount of mathematical involvement which quickly discourages, even seasoned, scientists, and engineers. To encourage the use of AM, this paper gives a brief review of the mathematical basis of AM followed by a historic perspective on the expansions originating from this mathematical basis. Specifically the case of a two-dimensional anisotropic plate with unloaded cut-outs subjected to in-plane static load is presented.

2006 ◽  
Vol 532-533 ◽  
pp. 341-344 ◽  
Author(s):  
Min Li Zheng ◽  
Bin Jiang ◽  
Bin Hu Chen ◽  
Yong Jun Sun

According to the characteristics of high speed face milling process, the models of the stress field for high speed face milling cutter with two sorts of structure are proposed and established. By means of the finite element analysis of the stress field for high speed face milling cutters, the law of influence of the cutter’s structure, the cutter’s subassemblies and the fixing rake of inserts on the stress field of cutter is acquired under the action of high rotate speed. In this foundation, the model reconstruction and the stress field analysis of the cutter are completed, and the model of evaluation for dynamic cutting performance of high speed face milling cutter is established. The results of high speed face milling experiment and frequency spectrum analysis of dynamic cutting force of the cutter indicate that high speed face milling cutter with the fixing rake of zero degree and less subassemblies takes on better dynamic high speed cutting performance.


2001 ◽  
Vol 69 (2) ◽  
pp. 130-138 ◽  
Author(s):  
Y. M. Lee ◽  
J. A. Wickert

A model is developed for predicting the stress field within a wound roll of web material, in which the radial, circumferential, transverse, and shear stresses can vary in both the roll’s radial and cross-web (transverse) directions. As has been the case in previous wound roll stress analyses based on one-dimensional models, the present approach accounts for the anisotropic and nonlinear material properties of the layered web material, and the incremental manner in which the roll is wound. In addition, the present development accounts for arbitrary cross-sectional geometry and material of the core, and the presence of nonuniform tension across the web’s width during winding. The solution is developed through an axisymmetric, two-dimensional, finite element analysis which couples individual models of the core and layered web region substructures. The core’s stiffness matrix at the core-web interface provides a mixed boundary condition for the web region’s first layer. In several parameter studies, variations of the stress components in the roll’s radial and cross-width directions are discussed and compared with predictions of the simpler companion one-dimensional model. The character of the stress field at the web region’s free edges and along the core-web interface, and the possibility of stress concentration or singularity existing there, are also discussed.


Author(s):  
Prashant Jindal ◽  
Frank Worcester ◽  
Anand Gupta ◽  
Philip Breedon

Nanoparticles in the form nanotubes and nanoplatelets have been compared for von Mises stresses by using them as low-composition reinforcements in titanium alloy–based mandible plate for different compositions and orientations. A finite element model has been designed to reconstruct a fractured human mandible with a titanium alloy mandible plate. A 500 N compressive force was applied on the mandible, and stress distribution across the plate sections was analysed for aligned two-dimensional random and three-dimensional random orientations for both tubes and platelets. Carbon material as graphene has been used for tube and platelet in the form of nanotubes and nanoplatelets, respectively. Using properties of graphene as the filler in titanium alloy plate, for both nanoplatelets and nanotubes, the stresses reduced between 5% and 25% for nanoplatelets and nanotubes graphene–titanium composite plates in comparison to non-reinforced plates, at critically stressed sections. Nanotubes exhibited stress reduction of nearly 23.4% for aligned configurations, while nanoplatelets exhibited stress reduction up to 21.2% for two-dimensional and three-dinemsional random configurations in comparison to non-reinforced titanium plates. Hence, it has been suggested that nanotubes exhibited superior mechanical reinforcement potential beyond that of aligned nanoplatelets, while nanoplatelets provided enhanced mechanical reinforcements for random configurations. Therefore, for biomedical implant applications nanocomposite materials can be designed with the same dimensional form but with lower compositions of filler materials by simply manipulating the appropriate orientations.


2021 ◽  
Vol 31 (4) ◽  
pp. 345-348
Author(s):  
Yasuhide Tsuji ◽  
Keita Morimoto ◽  
Akito Iguchi ◽  
Tatsuya Kashiwa ◽  
Shinji Nishiwaki

Author(s):  
Y Xu ◽  
B Liu ◽  
J Liu ◽  
S Riemenschneider

Empirical mode decomposition (EMD) is a powerful tool for analysis of non-stationary and nonlinear signals, and has drawn significant attention in various engineering application areas. This paper presents a finite element-based EMD method for two-dimensional data analysis. Specifically, we represent the local mean surface of the data, a key step in EMD, as a linear combination of a set of two-dimensional linear basis functions smoothed with bi-cubic spline interpolation. The coefficients of the basis functions in the linear combination are obtained from the local extrema of the data using a generalized low-pass filter. By taking advantage of the principle of finite-element analysis, we develop a fast algorithm for implementation of the EMD. The proposed method provides an effective approach to overcome several challenging difficulties in extending the original one-dimensional EMD to the two-dimensional EMD. Numerical experiments using both simulated and practical texture images show that the proposed method works well.


Sign in / Sign up

Export Citation Format

Share Document