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Abstract: Using
the wave propagation method (WPM), the forbidden band gaps of
one-dimensional phononic crystals are studied. Results obtained using
the method are evaluated against those by plane wave expansion (PWE). It
shows that the results of PWE are close to those of WPM with an
increasing of the wave number of PWE. Under the condition of the same
computational accuracy, the computing time of WPM is about one fiftieth
of that of WPE in the research of the forbidden band gaps in
one-dimensional binary phononic crystals, and one hundredth in
one-dimensional quaternary phononic crystals. Considering the changing
of elastic constants with frequency of viscoelastic material, the
forbidden band gaps can be obtained directly, and the computing time
of WPM is about two orders of magnitude lower than that of PWE
improved using iterative method.
Key words: Phononic crystals Forbidden band gaps
Wave propagation method Viscoelasticity
CLC No: O321 TH113 O48
Received 20060218, received in revised form 20060904
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