起落架舱声场激励下的客舱地板减振设计研究
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摘要
某型机在飞行过程中,起落架舱上方的客舱地板振动比较剧烈。本文首先对起落架舱的内部声场进行了计算,获得了舱内的非定常流场脉动信息以及舱内壁面的噪声频谱信息,此声场激励引发了气密地板的模态振动,导致气密地板和客舱地板振动比较剧烈;然后针对客舱地板的振动过度区域进行了减振隔振设计,并基于全机动力学有限元模型进行了仿真验证,优选了一套减振设计方案,使得客舱地板的振动响应水平明显下降,表明减振措施是合理有效的。
During the flight process of a certain aircraft, the vibration of cabin floor above the landing gear cabin is quite violent. Due to the gap around the landing gear, the air flow may easily get into the cabin interior through the gap, which can cause vibration and noise. In this paper, the internal acoustic field in the landing gear cabin is calculated, and the unsteady flow field information and the noise spectrum information of the cabin interior wall are obtained. The sound field excites the modal vibration of the airtight floor, resulting in the vibration of the cabin floor. Then, the vibration isolation design is carried out for the over-vibration area of the cabin floor, and the simulation is verified based on the aircraft dynamics finite element model. Finally, a set of vibration reduction design is optimized to reduce the vibration response level of the cabin floor, which indicates that the vibration reduction measures are reasonable and effective.
During the flight process of a certain aircraft, the vibration of cabin floor above the landing gear cabin is quite violent. Due to the gap around the landing gear, the air flow may easily get into the cabin interior through the gap, which can cause vibration and noise. In this paper, the internal acoustic field in the landing gear cabin is calculated, and the unsteady flow field information and the noise spectrum information of the cabin interior wall are obtained. The sound field excites the modal vibration of the airtight floor, resulting in the vibration of the cabin floor. Then, the vibration isolation design is carried out for the over-vibration area of the cabin floor, and the simulation is verified based on the aircraft dynamics finite element model. Finally, a set of vibration reduction design is optimized to reduce the vibration response level of the cabin floor, which indicates that the vibration reduction measures are reasonable and effective.
引文
[1]朱位秋.随机振动[M].北京:科学出版社,1992.(ZHUWeiqiu.Random vibration[M].Beijing:Science Press,1992(in Chinese)).
[2]杨卫平.飞机结构有限元建模指南[M].北京:航空工业出版社,2013.(YANG Weiping.Guide to finite element modeling of aircraft structures[M].Beijing:Aviation Industry Press,2013(in Chinese)).
[3]ANST.Mechanical vibration and shock-evaluation of human exposure to whole-body vibration-part1-general requirements:ANST/ISO 2631-1-1997[S].[S.l.]:US-ANSI,1997.
[2]杨卫平.飞机结构有限元建模指南[M].北京:航空工业出版社,2013.(YANG Weiping.Guide to finite element modeling of aircraft structures[M].Beijing:Aviation Industry Press,2013(in Chinese)).
[3]ANST.Mechanical vibration and shock-evaluation of human exposure to whole-body vibration-part1-general requirements:ANST/ISO 2631-1-1997[S].[S.l.]:US-ANSI,1997.