微穿孔板几何参数估算及其对吸声性能的影响

不规则孔微穿孔板几何参数无法直接获知,造成吸声性能计算困难,故提出一种微穿孔板几何参数估算方法。将不规则孔等效处理为圆孔,利用马氏理论关于圆孔微穿孔板的基本理论,建立了微穿孔板几何参数估算模型;将参数估算结果用于吸声性能预测,理论计算与实验结果吻合。根据微穿孔板几何参数对高吸声性能区域的影响,探讨了马氏理论适用极限与微穿孔板几何参数的关系,以及微穿孔板受粉尘污染后吸声性能演变规律。将微穿孔板参数点取在面积较大的高吸声性能区域中间部位,可获得较大的马氏理论适用极限;微穿孔板参数点位于高吸声性能区域右上部位时,一定程度的粉尘污染不会降低吸声性能. 

Estimation of geometric parameters for micro-perforated panels and their effect on absorption performance

The geometric parameters of micro-perforated panels with irregular holes cannot be directly known, making it difficult to calculate the sound absorption performance. Therefore, a method of estimating the geometric parameters of micro-perforated panels is proposed. The irregular holes are treated as equivalent circular ones, and the model of estimating the geometric parameters is established by using Maa's theory about the panel with circular holes. The result of the parameter estimation of a type of micro-perforated panel is used to predict the absorption performance,resulting in good agreement with experiments. According to the influence of the geometric parameters of the panel on the high absorption area, the relationship between the application limit of Maa's theory and the geometric parameters is discussed, and the evolution law of the sound absorption performance of the panel polluted by dust is investigated. When the parameters of the panel are designed near the center of the high absorption region, large value of the application limit of Maa's theory can be obtained;and if the parameters are located in the upper right part of the high absorption area, a certain degree of dust pollution of the panel does not reduce the sound absorption performance.