飞艇囊体膜弹性振动特性预测仿真  

Predictive Simulation of Elastic Vibration for an Airship Capsule

作　　者：宋林[1,2] 姜鲁华 张远平[1] SONG Lin;JIANG Lu-huang;ZHANG Yuan-ping(Academy of Opto-Electronics,Chinese Academy of Sciences,Beijing 100080,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院光电研究院,北京100080 [2]中国科学院大学,北京100049

出　　处：《计算机仿真》2019年第7期34-40,共7页Computer Simulation

基　　金：飞艇总体技术研究与试验(Y14202A16N)

摘　　要：研究飞艇囊体和声腔耦合作用下,飞艇囊体膜弹性振动特性。目前,研究飞艇囊体振动行为的主要方法是将囊体内外压差作为预应力施加在囊体上,对囊体进行模态分析,忽视了内部气体与囊体结构的耦合作用对囊体振动行为的影响。而柔性囊体结构振动受内部空气影响显著。将飞艇囊体形成的封闭腔体视为声腔,应用结构-声耦合分析方法,分析囊体和声腔耦合作用下,飞艇囊体振动的模态特性。得到囊体和声腔耦合作用下囊体振动的固有频率和模态振型,以及囊体内外压差对囊体振动的影响机理。为验证方法的有效性,应用结构-声耦合分析方法,建立矩形膜-声腔耦合系统的有限元模型,得到不同压差下,膜-声腔耦合系统的固有频率和模态振型;同时,建立矩形膜-声腔耦合系统的试验模型,测得系统的模态参数,验证结构-声耦合分析方法建立的有限元模型的有效性。结果表明,飞艇囊体与声腔的耦合作用使得飞艇囊体弹性振动的频率降低,囊体内外压差仅对特定的模态振型有影响。为研究飞艇囊体的动力学特性提供依据,也为飞艇囊体表面刚性结构布置和控制系统的设计提供参考。This paper researches the vibration characteristics of the airship capsule-acoustic cavity coupling system. At present, the method to analyze the vibration characteristics of the airship capsule is to load the pressure differential of airship capsule on the capsule as the preload and to analyze its model characteristics, which ignores the effect of airship capsule-acoustic cavity coupling on the capsule’s vibration behavior. The flexible airship’s dynamic behavior is seriously affected by the inner gas. In the paper, the structural-acoustic coupling analytical method was applied to build an airship capsule-acoustic cavity coupling system. Its modal parameters and mode shapes were obtained under different pressure differentials. Moreover, the structural-acoustic coupling analytical method was applied to build a finite element model for a rectangular membrane-acoustic cavity coupling system. The system’s modal parameters and the influence of the cavity’s pressure differential on the vibration behavior of the membrane structure were obtained. Then, a test model of the corresponding membrane-acoustic cavity coupling system was established to get the model parameters and verify the validity and accuracy of the finite element method established by the structural-acoustic coupling analytical method. The research shows that the airship capsule-acoustic cavity coupling obviously decreases the natural frequencies of the airship capsule and the pressure differentials only affect some specific modes. This research will provide evidence and reference for the research on the dynamic behavior of the airship capsule, the rigid structure’s arrangement on the surface of the airship and control system design.

关 键 词：膜-声腔耦合系统 结构-声学耦合分析方法 飞艇 

分 类 号：V274[航空宇航科学与技术—飞行器设计]