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Abstract: The
one dimensional plane wave expansion (PWE) algorithm is improved using
iterative method in order to solve the problem of nonlinear changing of
elastic constants with frequency, which is found in calculating of the
band gaps of one dimensional viscoelastic phononic crystals. The new
method is applied in the research of the vibration band gap of one
dimensional steel/butadiene acrylnitrile rubber (NBR) periodic
structure. The calculation results are in good agreement with the
experimental results. Further theoretical analyses shows that the
nonlinear changing of elastic constants with frequency of viscoelastic
rubber can remarkably increase the width of first band gap, and at the
same time hold the starting frequency of it. For the two cases, the
width of first band gap increased by 36.4% (for the 3 mm steel/10 mm NBR
periodic structure) and 34.0% (for the 7 mm steel/10 mm NBR periodic
structure) respectively.
Key words: Phononic crystals Vibration band gap
Viscoelasticity Plane wave expansion
CLC No: O321
TH113 O48
国家973重大基础研究资助项目(51307).
Received 20030526, received in revised form 20031120
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