基于Fano共振效应与多孔吸声的全向通风高铁声屏障

Omnidirectional ventilated high-speed rail sound barrier based on Fano resonance eff ect and porous sound absorption

针对现有高速铁路声屏障通风性能差、自重大的问题,提出了一种新型高铁声屏障设计。首先基于Fano共振效应提出一种由螺旋通道与中空通路相互组合的声学超单元结构,再根据隔、吸声相结合的设计理念在超单元内壁添加多孔材料形成复合结构,来进行声屏障的构建,并对声屏障整体结构进行了安全性分析。主要结论如下:参数优化后的超单元结构可以达到实际应用要求;复合结构的降噪效果优于单独的超单元,并通过参数化分析确定了选用厚度为15mm的多孔材料构建声屏障;相较超单元声屏障,复合结构声屏障在全频段范围内均表现出了出色的降噪效果,且具有全向性;所设计的声屏障可以保证在组合风荷载作用下的安全性,验证了设计的可行性。

Aiming at the problems of poor ventilation performance and heavy weight of existing high-speed railway sound barriers,a new design of high-speed railway sound barrier is proposed.Firstly,based on the Fano resonance effect,an acoustic meta unit structure consisting of spiral channel and hollow channel is proposed.Then,according to the design concept of the combination of insulation and absorption,porous materials are added to the inner wall of the meta unit to form a composite structure,so as to construct the sound barrier.The main conclusions are as follows:The meta unit structure after parameter optimization can meet the requirements of practical application;The noise reduction effect of the composite structure is better than that of the single meta unit,and the porous material with a thickness of 15mm is selected to construct the sound barrier through parametric analysis;Compared with the meta unit sound barrier,the composite structure sound barrier shows excellent noise reduction effect in the whole frequency range,and has omnidirectional;The designed acoustic barrier can ensure the safety under the combined wind load,which verifies the feasibility of the design.