Finite Element Analysis of CAD Large Assemblies

  • Date: 10/02/2007

Kirill Pichon (University Paris VI)


University of British Columbia


In today's product development and engineering process, usage of
computer aided design (CAD) platform is obvious. It allows crating of
quite realistic models, precisely describing not only the geometry of
the developed prototype, but also its physical properties. These
models, usually referred as parts, are brought together (assembled)
into assemblies, like it occurs in real world. The final digital
prototype consists sometimes of thousands of parts and sub-assemblies
so, its finite element based optimization is limited by computing
architectures that cannot hold and process large models in a timely
way. It is therefore desirable to use multiprocessor parallel computers
to solve the large mathematical systems. We propose to apply domain
decomposition methodology (DDM) to run numerical simulation of CAD
large assemblies. Instead of exporting a complex assembly as a single
component, and later dividing it in numerous, randomly created
sub-domains, we propose to use assembly topology, which was previously
created by designer while modeling process period. Thus, each part
represents an independent sub-domain, and could be analyzed
simultaneously with other parts, by sharing only the contact
information. In order to enforce the matching of the local solutions,
interface conditions and projection operators have to be written on the
boundary between sub-domains. These terms and conditions are imposed
iteratively. The convergence rate is very sensitive to these interface
conditions. The classical Schwarz algorithm without overlap, as well as
FETI-based methods are presented. A brief presentation of the finite
element open-source FreeFem3D software could be initiated.

Other Information: 

SCAIM Seminar 2007