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http://dx.doi.org/10.12989/sem.2007.26.1.031

The unsymmetric finite element formulation and variational incorrectness  

Prathap, G. (CSIR Centre for Mathematical Modelling and Computer Simulation)
Manju, S. (National Aerospace Laboratories)
Senthilkumar, V. (CSIR Centre for Mathematical Modelling and Computer Simulation)
Publication Information
Structural Engineering and Mechanics / v.26, no.1, 2007 , pp. 31-42 More about this Journal
Abstract
The unsymmetric finite element formulation has been proposed recently to improve predictions from distorted finite elements. Studies have also shown that this special formulation using parametric functions for the test functions and metric functions for the trial functions works surprisingly well because the former satisfy the continuity conditions while the latter ensure that the stress representation during finite element computation can retrieve in a best-fit manner, the actual variation of stress in the metric space. However, a question that remained was whether the unsymmetric formulation was variationally correct. Here we determine that it is not, using the simplest possible element to amplify the principles.
Keywords
mesh distortion; unsymmetric formulation; best-fit paradigm; parametric-metric element; projection theorem; three-node bar element;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
Times Cited By Web Of Science : 3  (Related Records In Web of Science)
Times Cited By SCOPUS : 3
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