WAVES AND VIBRATIONS IN INHOMOGENEOUS STRUCTURES ...

Inverse design of phononic crystals by tobology optimization 905
Finally we have compared the results obtained for the
infinite 2d case with topology optimized finite 2d structures.
When the size of the design domain is large (e.g. 10
wavelengths) we get full agreement with the infinite case
whereas for design domain dimension comparable to one
wavelength we get significantly different structures.
Although mixtures of the two materials are allowed,
the optimized designs for the base cell are all binary designs.
We interpret this as band gaps favouring high material
contrast.
We believe that the found designs are feasible in the sense
that they can be manufactured using machine or laser cutting.
Future work will include shell analysis and experiments.
Acknowledgments. This work was supported by the Danish Technical
Research Council through the project “Designing band gap materials
and structures with optimized dynamic properties”.
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