复合材料整流罩声学等效建模与低频隔声性能研究

Acoustic Equivalent Modeling and Low-Frequency Sound Insulation Performance Study for a Composite Fairing

运载火箭发射过程中的恶劣噪声环境会导致整流罩内部电子设备失效。开展整流罩的内声场环境预测以及隔声分析,对其降噪研究和优化设计具有重要意义。复合材料整流罩舱壁大量使用蜂窝夹芯板,基于蜂窝夹芯结构精细化模型开展整流罩内声场环境预示计算量大,无法适用。本文建立了复合材料蜂窝夹芯板的力/声学等效模型,并利用精细化模型验证等效模型的精度;进一步基于有限元-边界元方法对某整流罩结构进行低频声振分析;同时,对整流罩的隔声量进行了评价。结果表明:整流罩内声场在频率为160 Hz附近声学环境较为恶劣,整流罩的降噪研究应针对该频段进行。

The severe noise environment during the launch of vehicle may lead to the failure of internal electronic equipment.It is extremely important to conduct internal field environment prediction and insulation analysis for the noise reduction and optimization design of fairings.Since honeycomb core sandwich panels are vastly used on the bulkhead of fairings,it is computational expensive and impractical for fairings to conduct internal field environment prediction based on refined honeycomb core sandwich panel models.Therefore,a mechanical acoustic equivalent model is established for the composite honeycomb core sandwich pane,and the accuracy of the equivalent model is verified by the refined model.Furthermore,a low-frequency vibro-acoustic analysis of a fairing structure is conducted based on the finite element-boundary element model.Results show that the acoustic environment around 160 Hz is relatively severe in the internal field environment of the fairing,which indicates that the noise reduction research of the fairing should be concentrate on this frequency band.