计及温度条件下的微穿孔板结构优化设计

微穿孔板吸声体是由穿孔直径在1 mm以下的薄板和板后空腔组成的共振吸声结构,其结构通常可利用经典的微穿孔板理论来设计。但在温度变化条件下,经典的微穿孔板理论已经不足以设计出满足要求的微穿孔板结构。文中在设计微穿孔板吸声结构时,不仅考虑了结构参数孔径d、板厚t、孔间距b及空腔深度D对微穿孔板吸声特性的影响,又计入了温度T这一参数。拟采用改进的粒子群优化算法,分别对一定温度下的单层和双层微穿孔板吸声体的结构参数进行优化设计,搜索得到最优的参数组合,使其在给定的频带范围内平均吸声系数最高。优化结果表明:利用改进的粒子群算法设计出的微穿孔板吸声结构在给定频率范围内吸声系数较大,且符合给定温度的要求。

The structure optimization of micro-perforated panel absorber considering the effect of temperature

As a new promising sound absorption material, micro-perforated panel absorbers (MPPAs) have been successfully applied in various noise control occasions, even capable of working at harsh environments, including high temperature circumstances. According to Maa''s model, the sound absorption performance of a MPPA can be theoretically predicted as four parameters were chosen, i.e., the perforation diameter d, the panel thickness t, the distance between centers of adjacent perforations b, and the depth of the air gap D. However, the Maa''s model turns to be inaccurate at high temperatures. In this work, the temperature T is included into Maa''s model as the fifth parameter besides the four parameters. Simulation results show that better prediction accuracy could be obtained at high temperatures with the revised model. Furthermore, an improved particle swarm optimization algorithm is proposed to search for optimal structure parameters of mono-layer and double-layer MPPAs at given temperatures, which will facilitate the design work for MPPAs working at high temperatures.