【摘要】 采用铝熔体在周期多孔介质间渗流凝固方法制备了孔结构周期调制多孔铝合金,在试验范围内吸声系数的实验测量值与模型计算基本吻合,基于模型研究了调制周期数、调制顺序及同一周期单元内不同孔径层的厚度比与吸声性能的关系,表明孔径的调制分布对2 kHz以上的宽频声波吸收有较大影响,对低频吸收未发现明显改善.更多还原

【Abstract】 Porous aluminium with controlled periodic pore structures was processed by infiltration method.The results of sounds absorption within the range tested,which have been obtained by standing wave tube method around,are basically consistent with the simulation results.Based on the model,the relationship between pore structure parameters(periodic number,ratio with different layers,packing order) and sound absorption coefficient were studied.It is suggested that sound-absorption behavior(>2 kHz) is strongly affected by pore size distribution,but no apparent correlation in low frequency.更多还原