JAC2D: A two-dimensional finite element computer program for the nonlinear quasi-static response of solids with the conjugate gradient method; Yucca Mountain Site Characterization Project

The compound variable inverse problem which comprises boundary temperature distribution and surface convective heat conduction coefficient of two-dimensional steady heat transfer system with inner heat source is studied in this paper applying the conjugate gradient method. The introduction of complex variable to solve the gradient matrix of the objective function obtains more precise inversion results. This paper applies boundary element method to solve the temperature calculation of discrete points in forward problems. The factors of measuring error and the number of measuring points zero error which impact the measurement result are discussed and compared with L-MM method in inverse problems. Instance calculation and analysis prove that the method applied in this paper still has good effectiveness and accuracy even if measurement error exists and the boundary measurement points’ number is reduced. The comparison indicates that the influence of error on the inversion solution can be minimized effectively using this method.

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Large-Scale Parallel Finite Element Analysis of the Stress Singular Problems

10th International Conference on Nuclear Engineering, Volume 1 ◽

10.1115/icone10-22562 ◽

2002 ◽

Author(s):

Noriyuki Kushida ◽

Hiroshi Okuda ◽

Genki Yagawa

Keyword(s):

Finite Element ◽

Domain Decomposition ◽

Conjugate Gradient Method ◽

Conjugate Gradient ◽

Gradient Method ◽

Large Scale ◽

Preconditioned Conjugate Gradient Method ◽

Preconditioned Conjugate Gradient ◽

Singular Problems ◽

Parallel Finite Element

In this paper, the convergence behavior of large-scale parallel finite element method for the stress singular problems was investigated. The convergence behavior of iterative solvers depends on the efficiency of the preconditioners. However, efficiency of preconditioners may be influenced by the domain decomposition that is necessary for parallel FEM. In this study the following results were obtained: Conjugate gradient method without preconditioning and the diagonal scaling preconditioned conjugate gradient method were not influenced by the domain decomposition as expected. symmetric successive over relaxation method preconditioned conjugate gradient method converged 6% faster as maximum if the stress singular area was contained in one sub-domain.

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Elastic Stresses in Layered Snow Packs

Journal of Glaciology ◽

10.1017/s002214300002236x ◽

1972 ◽

Vol 11 (63) ◽

pp. 407-414 ◽

Cited By ~ 6

Author(s):

F. W. Smith

Keyword(s):

Finite Element ◽

Stress Distribution ◽

Computer Program ◽

Elastic Stress ◽

Two Dimensional ◽

Strength Data ◽

Elastic Stresses ◽

Stress Levels ◽

Dimensional Finite Element

Abstract A two-dimensional finite element computer program has been used to compute the elastic stress distribution in realistic multi-layered snow packs. Computations have been done on three-layered and five-layered snow packs intended to simulate conditions on the Lift Gully at Berthoud Pass, Colorado. Calculations have been performed to determine the effect of a layer of new snow and the effect of a weak sub-layer. Stress levels were obtained which are reasonable compared with available snow strength data.

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