中文摘要：

低频振动和噪声的控制问题是当今环境面临的重要挑战。基于声子晶体的局域共振机理,设计一种新型的螺旋局域共振单元声子晶体板结构,并结合数值计算和试验测试对结构的低频振动带隙特性进行分析和验证。分析发现,共振带隙的产生是由螺旋共振单元的局域共振模态与板中传播的弹性波相互耦合作用造成的,而且带隙宽度与耦合强度直接相关。通过改变结构的材料和尺寸参数可以将共振带隙调节到满足实际应用要求的低频范围。数值计算结果与试验测试结果基本一致,同时证实所设计的结构在250 Hz以下的低频范围具有较宽的振动带隙,最低带隙频率低至42 Hz。这种结构设计及其研究结果为声子晶体研究提供了获得低频振动带隙的理论依据和有效方法,在低频减振降噪方面具有潜在的应用前景。

英文摘要：

The reduction of low-frequency vibration and noise has been a challenging task. A design of phononic crystal plate with periodic novel spiral resonators is introduced based on the locally resonant mechanism of phononic crystals. The low-frequency band gap characteristics of the proposed structure are investigated numerically and experimentally. It is found that the interaction between the local resonances and the traveling wave modes in the plate results in the formation of the locally resonant band gap, whose bandwidth depends on interaction strength and can be modulated by changing structure parameters. By combining the numerically calculations and experimental measurements, the proposed phononic crystal structure is demonstrated to possess a broadband gap in low-frequency range below 250 Hz. The lowest frequency of the band gap is 42 Hz. There is a high level of agreement between the finite element calculation results and the experimental results. The structure design and its results provide theoretical basis and an effective way for phononic crystal to obtain band gaps in low-frequency range, which provides potential applications prospect in the low-frequency noise and vibration reduction.