【摘 要】
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In this work,the three-dimensional (3D) propagation behaviors in the nonlin-ear phononic crystal and elastic wave metamaterial with initial stresses are investigated.The analytical solutions of the fundamental wave and second harmonic with the quasi-longi
【机 构】
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Institute of Engineering Mechanics,Beijing Jiaotong University,Beijing 100044,China;Department of Me
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In this work,the three-dimensional (3D) propagation behaviors in the nonlin-ear phononic crystal and elastic wave metamaterial with initial stresses are investigated.The analytical solutions of the fundamental wave and second harmonic with the quasi-longitudinal (qP) and quasi-shear (qS1 and qS2) modes are derived.Based on the transfer and stiffness matrices,band gaps with initial stresses are obtained by the Bloch theorem.The transmission coefficients are calculated to support the band gap property,and the tunability of the nonreciprocal transmission by the initial stress is discussed.This work is expected to provide a way to tune the nonreciprocal transmission with vector charac-teristics.
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