【摘要】 使用驻波管法对不同打孔孔径和孔排列方式试样的吸声系数进行测试,通过吸声峰值、降噪系数、半峰宽3个角度来进行评价和分析。结果显示,只要打孔率相同,不同的孔排列方式的试样具有相似的吸声效果。吸声峰值随孔径增大向低频迁移;降噪系数随打孔率增大呈依次增大的趋势;孔径为1.5mm和2.5mm的试样半峰宽值远高于孔径3mm和3.5mm的试样。更多还原

【Abstract】 Sound absorption coefficient of closed-cell aluminum foam with different perforation size and arrangement was measured by standing-wave method.Sound absorption capacity was evaluated by the maximum sound absorption coefficient,noise reduction coefficient and half-peak width.The results show that specimens with perforation arranged in square way exhibit better sound absorption effect than those with perforation arranged in trigonal way.Sound absorption coefficient remains fundamentally unchanged as perforation size changes.The maximum sound absorption coefficient transfers to low frequency with increase of perforation size and noise!reduction coefficient rises with increase of perforation rate.The halfpeak width of specimens with perforation size of 1.5mm and 2.5mm is higher than those of 3mm and 3.5mm.更多还原