On the Importance of Displacement History in Soft-Body Contact Models

Abstract

Two approaches are commonly used for handling frictional contact within the framework of the Discrete Element Method (DEM). One relies on the Complementarity Method (CM) to enforce a non-penetration condition and the Coulomb dry-friction model at the interface between two bodies in mutual contact. The second approach, called the Penalty Method (PM), invokes an elasticity argument to pro- duce a frictional contact force that factors in the local deformation and relative motion of the bodies in contact. We give a brief presentation of a DEM-PM contact model that includes multi-time-step tangential contact displacement history. We show that its implementation in an open source simulation capability called Chrono is capable of accurately reproducing results from physical tests typical of the field of geomechanics; i.e., a direct shear tests on a mono-disperse material. Keeping track of the tangential contact displace- ment history emerges as a key element of the model. We show that identical simulations using contact models that include either no tangential contact displacement history or only single-time-step tangential contact displacement history are unable to accurately model the direct shear test.

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Document Details

Document Type
Technical Report
Publication Date
Jul 10, 2015
Accession Number
ADA622350

Entities

People

  • Dan Negrut
  • Jonathan Fleischmann
  • Paramsothy Jayakumar
  • Radu Serban

Organizations

  • United States Army Tank Automotive Research, Development and Engineering Center

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Computer Programs
  • Computer Simulations
  • Displacement
  • Engineering
  • Equations
  • Equations Of Motion
  • Euler Equations
  • Granular Materials
  • Materials
  • Mechanical Engineering
  • Modulus Of Elasticity
  • Particle Size
  • Particles
  • Shear Stresses
  • Shear Tests
  • Simulations
  • Stiffness

Fields of Study

  • Engineering

Readers

  • Computational Fluid Dynamics (CFD)
  • Fluid Dynamics.