A novel method for implementing contact/impact in an implicit nite element formulation is presented. The method uses the ideas of buoyancy to... Show moreA novel method for implementing contact/impact in an implicit nite element formulation is presented. The method uses the ideas of buoyancy to enforce the normal contact constraint and a velocity dependent force to model energy dissipation. Upon contact (penetration) a normal force equal to the depth of penetration times a target weight density (di erent and much larger than the actual material weight density) creates a normal pressure on the contacting body. In addition to the buoyancy force, the penetrating surface area is subjected to a drag-like force that acts in a direction opposite the velocity vector of the penetrating node of the contacting body . This rate dependence is broken up into components tangential and normal to the target surface. The normal component of the drag performs two functions. First it provides for an energy absorbing mechanism similar to a coe cient of restitution for modeling non-conservative systems. Secondly, it can provide damping (analogous to mathematical damping) which can aid in solution convergence. The tangential component of the damping force serves the function of modeling friction in a simpli ed manner. The method applies contact forces in the manner of external forces and as such lends itself well to simpli ed contact detection schemes which rely on functional representation of bodies. The method is described and demonstrated through several examples including a comparison to experimental data. Ph.D. in Mechanical and Aerospace Engineering, May 2012 Show less
Query
(-) mods_name_creator_namePart_mt:"Grudzinski, James John"