基于局域声子理论的铝合金型材低频降噪研究

Study on Low Frequency Noise Reduction of Aluminum Alloy Profiles Based on Local Phonon Theory

针对高速列车在运行过程中产生低频噪声对人体的伤害,基于声子晶体局域共振理论的阻尼动力吸振器模型对高速列车的地板结构进行理论分析和软件仿真,得出较优的地板结构布置和较高的隔声量。首先通过分析局域声子板的多自由度系统的振动的耦合基本特征,对高速列车地板进行结构模态分析,然后通过商业多物理场软件对列车地板声固耦合结构施加平面波辐射载荷,分析在低频频域范围内的局域声子板的声透射系数再计算入射能量与透射能量之间能量损失情况,最后通过对局域声子板材料的优化设置,选择合理、经济、高效的材料设置,在低频范围内得到较好的隔声量。研究结果表明:经过合理的布置局域声子板对地板结构在低频(100~500 Hz)内隔声有很大的提高。

High-speed trains have hurt the low-frequency noise on the human body in the process of operation,the phononic crystal local resonance theory type dynamic vibration absorber model theory analysis and software simulation of the floor structure of high-speed train based on sound insulation obtained better floor structure layout and high.Firstly,through the basic characteristics of coupling vibration of multi degree of freedom system analysis of local phonon plates,the modal analysis of the high speed train floor,to determine the optimal position of the optimal local phonon plate stiffness,damping,optimal settings,and then through the multi physics software business on the train floor acoustic coupling structure for plane wave radiation and sound transmission analysis of the coefficient of local phonon in low frequency domain within the scope of the calculation between the incident energy and transmission energy loss situation,finally by setting the optimization of local phonon plate material,the choice of reasonable,economical and efficient materials,get better sound insulation in low frequency range.The research results show that the sound insulation of the floor structure in the frequency domain(100 Hz-500 Hz)is greatly improved by the reasonable arrangement of the local phonon plates.