宽带低反射式通风声屏障  

Broadband ventilated acoustic barrier with low reflection

作　　者：张海龙[1,2] 李丽娟[1,2] 梁彬[1,2] 杨京[1,2] 程建春[1,2] Zhang Hailong Li Lijuan Liang Bin Yang Jing Cheng Jianchun(Institute of Acoustic, Nanjing University, Nanjing, 210093, China Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093)

机构地区：[1]南京大学声学研究所,南京210093 [2]人工微结构科学与技术协同创新中心,南京210093

出　　处：《南京大学学报（自然科学版）》2017年第1期56-60,共5页Journal of Nanjing University（Natural Science）

基　　金：国家自然科学基金(11634006;81127901);中兴通讯产学研合作基金

摘　　要：提出了一种基于长方晶格型声子晶体结构的波矢调制特性的声屏障设计机理.该声屏障能够以极低的反射率将入射声波导引至内部,并在相对于原有的传播方向偏移一定距离后出射,从而产生局部的声静区.由于该机理不依赖于粘滞吸收效应或负的等效声学参数,因而可保证出射声波的强度及波形均与入射声波相近,使得所设计的声屏障能够在隔声的同时有效地将入射声能量导引至预设的位置进行吸收或进一步利用,并且具有较宽的工作频带.数值计算结果证明在7750~10000Hz频率范围内均有35dB左右以上的隔声量,最大隔声量可达50dB.此外,区别于传统重墙隔声,声子晶体薄板在隔声时未导致背景媒质的阻断,留有与声波波长同尺度的间隙.这些特性对于在实际隔声问题中的应用具有重要价值.We propose a method based on the band structure of rectangular lattice type phononic crystal to realize the function of local noise barrier through manipulating the wave vector of the transmitted wave.The acoustic barrier has the ability to guide the incident sound wave with low reflection and creates a partial quiet area.The principle we propose neither rely on the effect of viscous absorption nor negative equivalent acoustic parameters which ensures the similarity of sound intensity and acoustic wavefront between the incident wave and transmitted wave.Simulation results show that sound insulation in the frequency range from 7750 Hz to 10000 Hz has a loss of more than 35 dB and the maximum sound pressure level loss reaches up to 50 dB contrasting acoustic wave propagating in the free field.Thin plates consisting phononic crystals insulate sound wave while leaving agap in acoustic wavelength scale which are different from the traditional method of sound insulation based on wall with the characters of huge mass density and large thickness.With the characters above,our design may have deep implication in practical applications.

关 键 词：声子晶体 能带结构 部分禁带 完全带隙 声屏障 

分 类 号：O402[理学—物理]