摘要
基于布拉格反射机理,自行制备了晶格常数同声波波长同数量级的二维钢/空气体系声子晶体结构模型,该模型具有双向可调性。研究了在填充分数较小(f<0.082)的情况下,单一方向(ГX)声波在二维声子晶体的声传播特性,得出其禁带频率范围。对1400Hz-3200Hz的声波垂直通过管阵列结构模型前后的声压级(SPL)进行了实验测试,发现了多处频段声压的加强与减弱区。研究了在管子直径及结构列间距不变的情况下增加排数及改变排间距两种情况下的禁带频率范围。得出了禁带宽度随着排数的增加和排间距的减小而明显加宽,并且最大插入损失的位置随着排间距的增加而降低这一规律。
We prepared a 2D steel/air system phononic crystal model based on the Bragg reflection mechanism. The crystal lattice constant has the same size as the sound wavelength, and the structure can be modulated in two directions. Under low filling fraction （f〈0.082）, sound propagation through 2D phononic crystal in single direction （GX） is studied to give the range of band-gap. We tested the sound pressure level before and after the sound （1 400Hz-3 200Hz） passed through the steel array structure perpendicularly. We found the enhanced and weak section frequency at many locations, and analyzed it using a plane wave method. Two types of band-gap have been studied under the condition of the fixed diameter with the space between columns to be increased by the row number and to be altered between rows. We conclude that the width of band-gap rise with increasing rows, and the location of the maximal insertion loss is reduced with the increasing space between rows.
出处
《声学技术》
CSCD
北大核心
2007年第2期238-242,共5页
Technical Acoustics
基金
国家自然科学基金项目(10574043)
教育部科技重点项目(106051)
声场声信息国家重点实验室基金项目(200505)
关键词
声子晶体
带隙
布拉格反射
phononic crystals
band-gap
Bragg reflection
