Lessons Learned and Best Practices for Utilizing a Generalized Composite Impact Model

Robert K Goldberg; Trenton M Ricks

NASA NTRS · 20220004943

Lessons Learned and Best Practices for Utilizing a Generalized Composite Impact Model

Abstract

A material model which incorporates several key capabilities which have been identified as lacking in currently available composite impact models has been developed. The material model utilizes experimentally based tabulated input to define the evolution of plasticity and damage as opposed to specifying discrete input parameters (such as modulus and strength). It has been implemented into the commercially available transient dynamic finite element code LS-DYNA® as MAT_213. The model can simulate the nonlinear deformation, damage and failure that take place in a composite under dynamic loading conditions. As MAT_213 is now being used by a general user community that did not participate in the model development process, a number of issues have been identified that caused uncertainty in assembling a MAT_213 input deck and conducting a MAT_213 analysis. The overall goal of this effort is to develop a quantified set of lessons learned and best practices which will permit a new user to conduct useful MAT_213 simulations without needing to have detailed expert knowledge of the material model and its theoretical underpinnings.

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Micromechanics Polymer Matrix Composites Impact

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Robert K Goldberg, Trenton M Ricks. Lessons Learned and Best Practices for Utilizing a Generalized Composite Impact Model. https://ntrs.nasa.gov/citations/20220004943

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