Implementing Linear Modelling of Interface Damping in a Finite Element Software
(English)In: Finite elements in analysis and design (Print), ISSN 0168-874XArticle in journal (Other academic) Submitted
In the automotive industry virtual modelling of losses in a built-up structure is still a challenge. A body-in-white car structure consists of many spot-welded parts and the modelling of their associated losses is highly interesting. For this purpose, the dissipation of mechanical energy is here modelled in the frame of large scale computations using linear techniques with commercially available finite element software. Mechanical, vibration damping is introduced through external forces which are pairwise applied such that they oppose the relative motion at the contact interfaces between two parts. Two aspects are investigated, first if the proposed modelling captures the main mechanisms of the damping on a system level. Second, if the predicted local vibration responses at different locations correlate well between predicted and previously measured (in vacuo) spectra. Initial simulations show promising results and the level of damping observed in the predictions are similar to the measured spectra, fo rvibration shapes which involve significant relative motion along the spot-welded surfaces. An advantage with this technique is that it helps in understanding of different sources of total system damping, i.e. due to material and other sources of damping. It is verified that non-material damping due to mechanical contact is a significant contributor to the losses in a built-up structure which may be simulated with the proposed technique. In the paper the overall approach is discussed together with the specific aspects of the finite element implementation technique proposed.
Interface damping, Mechanical contact damping, Air damping, Air pumping, Material damping, Vibration reduction, Loss factor, Finite element method.
Other Mechanical Engineering
IdentifiersURN: urn:nbn:se:kth:diva-93781OAI: oai:DiVA.org:kth-93781DiVA: diva2:523832
QS 20122012-04-262012-04-262012-04-26Bibliographically approved