针对变电站低频噪声难治理的问题,选用聚酯纤维,采用阻抗管研究其低频吸声性能,考察容重、材料厚度、背后空腔厚度对其低频吸声性能的影响,并将聚酯纤维与亥姆霍兹共振器组成复合结构,结果表明:聚酯纤维的容重对于吸声性能存在一个最佳范围;增加材料厚度和背后空腔厚度均能提高聚酯纤维的低频吸声系数,但是在100 Hz处的吸声系数仍然偏低;聚酯纤维与亥姆霍兹共振器复合结构在100 Hz处的吸声系数达到0.9以上,同时其平均吸声系数也处于较高水平.%In view of the problems of low frequency noises in substation,the polyester fiber impedance tube is chosen to study the low frequency sound absorption properties of polyester fiber.The influences of bulk density,material thickness,air cavity on the low frequency sound absorption properties are discussed with composite structure of polyester fiber and Helmholtz resonator.The results show that the bulk density of polyester fiber has an optimum range for sound absorption performance.The low frequency sound absorption coefficient of polyester can be improved by increasing the thickness of both the polyester fiber and air cavity while it is still low at 100 Hz;The sound absorption coefficient of composite structure of polyester fiber and Helmholtz resonator can reach up to 0.9 at 100 Hz while their average sound absorption coefficient is also high.
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