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关于微穿孔板吸声结构,已有完整的理论和设计数据.近年来,它在工业噪声控制中的应用越来越广泛,已从普通低速通风排气管道的消声,发展到燃气轮机排气噪声和叶轮机颤振噪声的降低.燃气轮机排气噪声高达130～140dB,流速也不低;而叶轮机叶尖处的流速则在250～300m/s左右,声压级在110dB以上.考虑到高流速和高声级的情况,微穿孔板吸声结构的设计要作必要的修正;一般来说穿孔率要适当提高,同时穿孔的孔径可从丝米级加大到毫米级.这样的结构仍不必附加多孔性吸收材料,因而对流场的影响不大,制作上也较方便.
There is a complete theoretical and design data on the sound absorption structure of micro-perforated plates.In recent years, its application in industrial noise control has become more and more widespread, from the muffler of common low-speed ventilation exhaust pipe to the gas turbine exhaust Noise and turbocharger flutter noise reduction.Gas turbine exhaust noise up to 130 ~ 140dB, the flow rate is not low; and the turbine blade tip velocity is about 250 ~ 300m / s, sound pressure level above 110dB. Taking into account High flow rate and high sound level, micro-perforated plate sound absorption structure design to make the necessary amendments; generally speaking, the perforation rate should be appropriately increased, while the perforation of the hole diameter can be increased from the millimeter to millimeters. Such a structure Still do not have to attach porous absorbent material, so little effect on the flow field, the production is more convenient.