圆柱形声腔内衬三聚氰胺泡沫降噪方法

发布时间：2018-01-08 21:18

本文关键词：圆柱形声腔内衬三聚氰胺泡沫降噪方法　出处：《宇航学报》2016年10期 　论文类型：期刊论文

【摘要】：针对运载火箭整流罩内高强度的噪声问题,采用圆柱声腔内衬理论、有限元仿真和声学试验研究了三聚氰胺泡沫材料的中低频(100~400 Hz)降噪特性。将三聚氰胺泡沫内衬等效为阻抗边界,给出了圆柱声腔简正频率的修正公式。测试了20 mm、30 mm、40 mm厚三聚氰胺泡沫的流阻和吸声系数,通过虚拟阻抗管仿真校验了三聚氰胺泡沫的声学参数、给出了表面声阻抗率。对比了内衬理论、阻抗边界仿真、实体仿真的简正频率。建立了运载火箭整流罩圆柱段缩比模型的噪声试验平台,对空桶和敷设三种厚度三聚氰胺泡沫等四种工况进行了仿真分析和噪声试验,对比了不同厚度三聚氰胺泡沫的降噪效果。结果表明圆柱声腔内衬三聚氰胺泡沫后简正频率减小,且减小量与三聚氰胺泡沫衬里的厚度成正比;三聚氰胺泡沫衬里在中低频段仍能达到约4~8 d B的降噪效果。
[Abstract]:Aiming at the problem of noise rocket in high strength, the cylindrical cavity lining theory, finite element simulation and experimental study on the low frequency acoustic melamine foam (100~400 Hz). The noise characteristics of melamine foam lining is equivalent to the impedance boundary, given the correction formula of positive frequency of cylindrical cavity. Jane tested 20 mm, 30 mm, flow resistance and absorption coefficient of 40 mm thick melamine foam, the acoustic parameters of melamine foam simulation verification through the virtual impedance tube, gives the surface acoustic impedance. Comparison of lining theory, impedance boundary simulation, frequency is established. The simulation of Jane rocket cylindrical section scale noise test platform model the simulation, analysis and noise test on the empty barrel and the laying of three kinds of thickness of melamine foam and four working conditions, compared to the noise reduction effect of different thickness of melamine foam Results. The results show that the cylindrical cavity lined with melamine foam after normal frequency decreases, and the reduction of melamine foam lining thickness is proportional to the noise reduction effect; melamine foam lining in the low frequency band can still reach about 4~8 D B.

【作者单位】：北京理工大学宇航学院;武汉理工大学理学院;北京强度环境研究所可靠性与环境工程技术重点实验室;
【基金】：民用航天预先研究项目
【分类号】：V421
【正文快照】： 3.北京强度环境研究所可靠性与环境工程技术重点实验室,北京100076)0引言在运载火箭发射过程中,由于发动机尾部喷流噪声和气动噪声的作用,整流罩内存在高声压级的噪声环境(总声压级约为120~140 d B)。该噪声环境下航天器的敏感组件(如太阳能帆板、电源等)将存在失效的风险。近

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