各向异性周期阵列结构吸声材料优化设计

Optimal Design of Anisotropic Periodic Array Sound Absorption Material

吸隔声结构的壁面材料通常要具有高吸声及低反射特性。对于一种采用各向异性吸声材料的吸声壁面,通过建立各向异性吸声板声压反射系数方程,以平均声反射系数最小为目标,优化求解了该吸声板的平均声反射系数,研究表明:对该吸声材料,在0～90°入射范围内平均反射系数最小值为0.283 5;当希望噪声在法向处反射也能最小时,0～90°入射范围内其最小平均声反射系数为0.293;而如果要求在法向处不反射,并使得0～60°上的平均声反射系数最小,在该角度范围内,平均声反射系数最小可达0.022,反射声功率比小于1e-3。相比于各向同性吸声层,各向异性吸声板在吸声应用中可获得更高性能。

Wall materials of sound absorption and insulation structures are often required high sound absorption and low re-flection performance. An anisotropic material used in sound absorption wall is discussed in the paper. The sound pressure re-flection coefficient equations of anisotropic acoustic panels are established, with minimum average reflection coefficient as an objective, the average sound reflection coefficient is solved by optimized methods. The researches show the minimum average reflection coefficient of the structure within the angle range of 0~90° is 0.283 5. When both the normal reflection and the average reflection are simultaneously minimized, the average reflection value is 0.293. If it is not reflected at the normal direc-tion, and the average acoustic reflection coefficient is minimum between 0 and 60 degrees, the minimum reflection coefficient is up to 0.022 in the angle range and the ratios of the sound reflection is less 1 e-3. For engineering design of sound absorp-tion wall, the structures made by anisotropic periodic array acoustic absorption material have higher performance than isotrop-ic acoustic panel when properly designed.