Abstract: An analytical method for the sound absorption performance of the acoustic coating with cavities has been proposed to investigate the effect of the hydrostatic pressure on the performance of the acoustic coating with the consideration of the deformation and prestress of the cavities. By using the finite element method, the sound absorption performance of the acoustic coating that only considers the deformation of the cavities is compared with that of the acoustic coating that considers the deformation and prestress of the cavities under the same hydrostatic pressure. The differences of the maximum deformation, average absorption coefficient and absorption coefficient variation are then studied for the acoustic coating with cylinder, conical and horn cavities under the same porosity and different hydrostatic pressure. The results show that there are significant differences between the sound absorption performance of the acoustic coating that only considers the deformation of the cavities and that of the acoustic coating that considers the deformation and prestress of the cavities. The hydrostatic pressure causes the largest deformation of the coating with cylinder cavities, followed by the coating with horn cavities, and then the coating with conical cavities. The effect of the hydrostatic pressure on the acoustic coating can be neglected below 2000 Hz. The absorption coefficient curves of the acoustic coating with cylinder cavities and conical cavities gradually get closer with the increase of the hydrostatic pressure, and almost match to each other under 10 MPa hydrostatic pressure.

Key words: hydrostatic pressure, acoustic coating, cavity deformation, prestress, absorbing performance

摘要： 该文考虑静压作用产生的空腔变形及其预应力状态,建立空腔型吸声覆盖层吸声性能分析方法,研究静压作用对吸声覆盖层性能的影响规律。通过有限元法对比在相同静压下仅考虑空腔变形以及考虑空腔变形和同时存在预应力时的覆盖层吸声性能,进而研究了不同静压下含圆柱形、圆锥形和喇叭形空腔覆盖层在孔隙率相同时,覆盖层的最大变形量、平均吸声系数和吸声系数变化量等性能参数的差异。结果表明：仅考虑空腔变形以及考虑空腔变形和存在预应力时覆盖层的吸声性能有明显差异。静压使圆柱形空腔覆盖层的变形量最大,其次是喇叭形空腔覆盖层,圆锥形空腔覆盖层的最大变形量最小。静压对于3类覆盖层在2 000 Hz频率点以下的影响较小。随着静压的增加,圆柱形和圆锥形空腔的吸声系数曲线逐渐靠近,在10 MPa下几乎重合。

关键词: 静压, 吸声覆盖层, 空腔变形, 预应力, 吸声性能