59th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference at AIAA SciTech 2018 Kissimmee, Florida, USA 8 - 12 January 2018

AIAA-2018-0903

Multiscale Modeling of Effective Piezoresistivity and Implementation of Non-Local Damage Formulation in Nanocomposite Bonded Explosives

K. Talamadupula and G. Seidel
Virginia Polytechnic Institute and State University, Blacksburg, VA, 24061-0203, USA

This work proposes the use of a non local damage law to describe the damage behavior of an NCBX material at the microscale. This study also aims to link damage to the strain sensing and damage sensing capabilities of this material due to the piezoresistivity derived from the presence of CNTs in the nanocomposite binder. Previous modeling efforts with respect to strain sensing and damage sensing of NCBX materials will be taken advantage of.1–6 The microscale RVE used for numerical studies is generated with the help of an SEM micrograph of a surrogate energetic pullout. Quasi static tensile simulations are done with 2D finite elements (CST) on this RVE. Damage modeling efforts are supported with element deletion algorithms that simulate cracks through the RVE and eventual final failure. The framework developed here will be used to study the impact of strength of the grain, nanocomposite binder and the interface along with their associated damage parameters. Comparisons of simulation results will be made using the various material mediums through which damage is made possible and also with interfacial damage between material mediums. The implemented non-local damage law is expected to avoid the numerical and mathematical difficulties associated with a traditional softening law.