摘要
为衰减中低频振动噪声,本文设计了一种非严格对称的开口圆环类声子晶体结构,基于有限元法和弹性波理论分析了其禁带特性和各方向的振动衰减性能;结合系统的振动模态解释了带隙打开和关闭的原因,并分析了几何参数对带隙宽度的影响规律。结果表明:由于晶体的非严格对称,仅ΓX方向的传输损耗和禁带特性吻合,且衰减性能优于MΓ方向,禁带内平均衰减27.8 dB,同比提升了5.5 dB。禁带内几乎没有产生位移变形量,而通带因无法抑制弹性波传播导致变形量显著增大;芯体的水平和旋转运动是带隙起始、截止的明显标志。以钨为芯体,能获得起始频率和带宽均为500 Hz的低频带隙,增大芯体的材料密度、填充率和晶格尺寸有助于获得较低频率的完整带隙。
In order to attenuate the mid-and low-frequency vibration noise,a non-strictly symmetrical open ring-like phononic crystal structure was designed.Based on the finite element method and elastic wave theory,its band gap characteristics and vibration attenuation performance in various directions were analyzed;Combined with the vibration mode of the system,the reasons for the opening and closing of the band gap were explained,and the influence of geometric parameters on the band gap width was analyzed.The results show that due to the non-strict symmetry of the crystal,only the transmission loss in theΓX direction is consistent with the band gap characteristics,and the attenuation performance is better than that in the MΓdirection.The average attenuation in the band gap is 27.8 dB,which is 5.5 dB higher than that in the MΓdirection.There is almost no displacement deformation in the forbidden band,and the deformation of the pass band significantly increases due to the inability to suppress the propagation of elastic waves;the horizontal and rotational movement of the core is an obvious sign of the beginning and end of the band gap.With tungsten as the core,the starting frequency and bandwidth are 500 Hz.Increasing the material density,filling rate and lattice size of the core will help to obtain a complete band gap at lower frequencies.
作者
唐荣江
潘朝远
郑伟光
何宏斌
唐经添
TANG Rongjiang;PAN Chaoyuan;ZHENG Weiguang;HE Hongbin;TANG Jingtian(School of Mechanical and Electrical Engineering,Guilin University of Electronic Technology,Guilin 541004,China)
出处
《人工晶体学报》
CAS
北大核心
2021年第3期428-434,共7页
Journal of Synthetic Crystals
基金
国家自然科学基金(52065013)
广西青年科学基金(2018GXNSFBA281012)。
关键词
圆环类声子晶体
带隙结构
方向传输损耗
几何尺寸
振动衰减性能
ring-like phononic crystal
band gap structure
directional transmission loss
geometric size
vibration attenuation performance
