A new model is proposed for determining the band gaps of flexural wave propagation in periodic fluid-filled micropipes with circular and square thin-wall cross-sectional shapes, which incorporates temperature, microst...A new model is proposed for determining the band gaps of flexural wave propagation in periodic fluid-filled micropipes with circular and square thin-wall cross-sectional shapes, which incorporates temperature, microstructure, and surface energy effects. The band gaps depend on the thin-wall cross-sectional shape, the microstructure and surface elastic material constants, the pipe wall thickness, the unit cell length, the volume fraction, the fluid velocity in the pipe, the temperature change,and the thermal expansion coefficient. A systematic parametric study is conducted to quantitatively illustrate these factors. The numerical results show that the band gap frequencies of the current non-classical model with both circular and square thin-wall cross-sectional shapes are always higher than those of the classical model. In addition,the band gap size and frequency decrease with the increase of the unit cell length according to all the cases. Moreover, the large band gaps can be obtained by tailoring these factors.展开更多
A new model for producing band gaps for flexural elastic wave propagation in a periodic microbeam structure is developed using an extended transfer matrix method and a non-classical Bernoulli–Euler beam model that in...A new model for producing band gaps for flexural elastic wave propagation in a periodic microbeam structure is developed using an extended transfer matrix method and a non-classical Bernoulli–Euler beam model that incorporates the strain gradient,couple stress and velocity gradient effects.The band gaps predicted by the new model depend on the three microstructure-dependent material parameters of each constituent material,the beam thickness,the unit cell length and the volume fraction.A parametric study is conducted to quantitatively illustrate these factors.The numerical results reveal that the first band gap frequency range increases with the increases of the three microstructure-dependent material parameters,respectively.In addition,the band gap size predicted by the current model is always larger than that predicted by the classical model,and the difference is large for very thin beams.Furthermore,both the unit cell length and volume fraction have significant effects on the band gap.展开更多
基金the National Key R&D Program of China(No.2018YFD1100401)the National Natural Science Foundation of China(Nos.12002086,11872149,and 11772091)。
文摘A new model is proposed for determining the band gaps of flexural wave propagation in periodic fluid-filled micropipes with circular and square thin-wall cross-sectional shapes, which incorporates temperature, microstructure, and surface energy effects. The band gaps depend on the thin-wall cross-sectional shape, the microstructure and surface elastic material constants, the pipe wall thickness, the unit cell length, the volume fraction, the fluid velocity in the pipe, the temperature change,and the thermal expansion coefficient. A systematic parametric study is conducted to quantitatively illustrate these factors. The numerical results show that the band gap frequencies of the current non-classical model with both circular and square thin-wall cross-sectional shapes are always higher than those of the classical model. In addition,the band gap size and frequency decrease with the increase of the unit cell length according to all the cases. Moreover, the large band gaps can be obtained by tailoring these factors.
基金The work reported here is funded by the National Natural Science Foundation of China[grant numbers 12002086,11872149 and 11472079]the Fundamental Research Funds for the Central Universities[grant number 2242020R10027].These supports are gratefully acknowledged.
文摘A new model for producing band gaps for flexural elastic wave propagation in a periodic microbeam structure is developed using an extended transfer matrix method and a non-classical Bernoulli–Euler beam model that incorporates the strain gradient,couple stress and velocity gradient effects.The band gaps predicted by the new model depend on the three microstructure-dependent material parameters of each constituent material,the beam thickness,the unit cell length and the volume fraction.A parametric study is conducted to quantitatively illustrate these factors.The numerical results reveal that the first band gap frequency range increases with the increases of the three microstructure-dependent material parameters,respectively.In addition,the band gap size predicted by the current model is always larger than that predicted by the classical model,and the difference is large for very thin beams.Furthermore,both the unit cell length and volume fraction have significant effects on the band gap.
