Third M.I.T. Conference on Computational Fluid and Solid Mechanics June 14–17, 2005  

Multi-bodies impacting a deformable structure

Photios P. Papados*
US Army Engineer Research and Development Center, 7701 Telegraph Road, Alexandria, VA 22315, USA

  Full Text
ABSTRACT
It is of keen interest to understand the interaction of multiple bodies impacting a deformable structure. It is of further importance to understand the errors arising from using simplified versus more accurate representations of the multi-bodies in the numerical scheme used to perform these simulations. In the past, researchers avoided the explicit modeling of the impacting bodies and resorted to the use of a crude pressure-time history representing the transfer of impulse (kinetic energy) from the impacting entities to the target. The reasons for these oversimplifications arose from hardware and software limitations. The drawback is that the errors arising from such an approach were extremely high and, in many cases, unacceptable. The advent, however, of parallel platforms and scalable software in conjunction with more sophisticated material models allows the researchers to approach the problem at hand within a reasonable turn-around time. In the current study only explicit modeling of the impacting bodies will be addressed. The focus of this paper is to present (a) the current methodology for modeling multi-body impact, (b) the possible options of simplified vs. non-simplified numerical simulations, and (c) a measure of error introduced by comparing the two approaches.

Keywords:  Multi-bodies; Erosion; Error estimate; Impact; dynamics; Kinetic energy; Constitutive laws; Scalable software

* Tel.: +1 (703) 428 7644; Fax: +1 (703) 428 6656; E-mail: photios.papados@tec02.usace.army.mil