承压条件下声子晶体吸声性能研究

声子晶体是一种新的吸声材料,研究了局域共振单元包覆层模量、厚度以及橡胶基体模量对声子晶体共振吸声频率、吸声系数的影响规律。在常压及承压条件下,包覆层模量越高,厚度越小,共振吸声频率越高,其规律符合共振频率与包覆层模量、厚度之间的关系。随着压力的增加,声子晶体的共振吸声频率均向高频移动。承压条件下,包覆层模量较低的样品低频吸声系数略高。包覆层厚度为2mm的样品,常压及承压条件下低频吸声系数数值变化较小。基体橡胶模量对声子晶体吸声频率和吸声系数未见明显影响。

Study on the Sound Absorption Properties of Phononic Crystal under Pressure Conditions

Phononic crystal is a new kind of sound absorption materials. The effects of coating layer＇s modulus, thickness and matrix＇s modulus on sound absorption frequency and coefficient under atmospheric pressure and pres- sure conditions were studied. It was found that the resonance absorption frequency was higher with the higher coat- ing layer＇s modulus and the smaller thickness, and this law accorded with the relationship of resonance frequency and the coating layer＇s modulus and thickness. As the pressure was higher, the resonance absorption frequency all became higher. The sound absorption coefficient of low frequency range was slightly higher with lower coating layer＇s modulus and changed slightly with 2ram coating layer＇s thickness under pressure. The effects of change of matrix＇s modulus on sound absorption frequency and coefficient were not obvious.