【摘要】 我们研究了消声水池用的宽带吸声器.为了增加丁基胶的损耗和可压缩性,用石粉作填料,得到了具有高损耗的吸声材料.用含气泡的(石至)石粉,可将橡胶的体积压缩形变转变为材料的剪切形变,致使材料的有效损耗因子随着气泡的体积率的增加而增加. 为了节省材料,选择了平板尖劈平行通道型吸声结构,它的总长是20cm和15cm(过渡部分分别为15cm和10cm).通道宽度是3cm,在频率范围5—80kc/s,声压反射系数小于10%.更多还原

【Abstract】 The broad-band absorbers for anechoic tank have been developed. Vermiculite flakes were used as filler to increase the loss and to improve the compressibility of butyl rubber, a sound absorbing material with high loss was thus obtained. By adding air bubbles in vermiculite flakes, the bulk compressive strain in rubber is changed into shear strain. Therefore, the effective loss factor of material increases with increase of the volume ratio of the bubble.Rib structures with parallel channel with total lengths of 20 cm and 15 cm (transition part being 15 cm and 10 cm respectively) have been used for the purpose of economy of the testing material. The channel width is 3 cm The reflection coefficient is less than 10% in the frequency range of 5-80kHz.更多还原