Numerical Simulations of iCMEs and Comparison with Heliospheric Images

Abstract

This paper presents the extension of some finite elements with embedded strong discontinuities to the fully transient range with the focus on dynamic fracture. Cracks and shear bands are modeled in this setting as discontinuities of the displacement field, the so-called strong discontinuities, propagating through the continuum. These discontinuities are embedded into the finite elements through the proper enhancement of the discrete strain field of the element. General elements, like displacement or assumed strain based elements, can be considered in this framework, capturing sharply the kinematics of the discontinuity for all these cases. The local character of the enhancement (local in the sense of defined at the element level, independently for each element) allows the static condensation of the different local parameters considered in the definition of the displacement jumps. All these features lead to an efficient formulation for the modeling of fracture in solids, very easily incorporated in an existing general finite element code due to its modularity. We investigate in this paper the use of this finite element formulation for the special challenges that the dynamic range leads to. Specifically, we consider the modeling of failure mode transitions in ductile materials and crack branching in brittle solids. To illustrate the performance of the proposed formulation, we present a series of numerical simulations of these cases with detailed comparisons with experimental and other numerical results reported in the literature. We conclude that these finite element methods handle well these dynamic problems, still maintaining the aforementioned features of computational efficiency and modularity.

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Document Details

Document Type
Technical Report
Publication Date
May 06, 2010
Accession Number
ADA531370

Entities

People

  • Angelos Vourlidas
  • Ilia Roussev
  • Noe Lugaz
  • W. Manchester ;t. Gombosi

Organizations

  • University of California, Berkeley

Tags

DTIC Thesaurus Topics

  • Astronomy
  • Discontinuities
  • Dynamic Range
  • Earth Sciences
  • Elongation
  • Engineering
  • Environment
  • Environmental Engineering
  • Failure Mode And Effect Analysis
  • Finite Element Analysis
  • Information Operations
  • Line Of Sight
  • Magnetic Fields
  • Simulations
  • Space Weather
  • Test Methods
  • Universities

Fields of Study

  • Engineering

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Mechanical Engineering/Mechanics of Materials.