A DCAMM seminar will be presented by
Associate Professor A. Srikantha Phani
Department of Mechanical Engineering,
University of British Columbia
Vancouver, Canada
Abstract:
Sandwich panels are extensively used in constructional, naval and aerospace structures due to their high stiffness and strength-to-weight ratios. In contrast, sound transmission properties of sandwich panels are adversely influenced by their low effective mass. Phase velocity matching of structural waves propagating within the panel and the incident pressure waves from the surrounding fluid medium leads to coincidence effects (often within the audible range) resulting in reduced impedance and high sound transmission. Truss-like lattice cores with porous microarchitecture and reduced inter panel connectivity relative to honeycomb cores promise the potential to satisfy the conflicting structural and vibroacoustic response requirements. This study combines Bloch-wave analysis and the Finite Element Method to understand wave propagation and hence sound transmission in sandwich panels with a truss lattice core. Three dimensional coupled fluid-structure finite element simulations are conducted to compare the performance of a representative set of lattice core topologies. Potential advantages of sandwich structures with a lattice core over the traditional shear wall panel designs are identified. The significance of partial band gaps is evident in the sound transmission loss characteristics of the panels studied. This work demonstrates that, even without optimization, significant enhancements in sound transmission loss performance can be achieved in truss lattice core sandwich panels compared to a traditional sandwich panel with a honeycomb core under constant mass constraint. The seminar will begin with a brief summary of elastostatic response tailoring of vascular stents, inspired by structural lattice mechanics. Then follows the elastodynamic response of sandwich panels with a truss lattice core.
Danish pastry, coffee and tea will be served 15 minutes before the seminar starts.
All interested persons are invited