细长体飞行器自由边界热模态试验与仿真  

Thermo-modal test and simulation of spindly vehicle in free boundary conditions

作　　者：唐晓峰 常洪振[3] 何振威[3] 史晓鸣 唐国安 TANG Xiaofeng;CHANG Hongzhen;HE Zhenwei;SHI Xiaoming;TANG Guoan(Department of Aeronautics and Astronautics,Fudan University,Shanghai 200433,China;Shanghai Electro-Mechanical Engineering Institute,Shanghai 201109,China;Beijing Institute of Structure and Environment Engineering,Beijing 100076,China)

机构地区：[1]复旦大学航空航天系,上海200433 [2]上海机电工程研究所,上海201109 [3]北京强度环境研究所,北京100076

出　　处：《航空学报》2018年第10期145-156,共12页Acta Aeronautica et Astronautica Sinica

基　　金：上海航天科技创新基金(SAST201605)

摘　　要：随着耐热承载一体化材料在新型高超声速飞行器上的应用,承力结构的工作温度不断提高,各类热模态特性逐渐得到关注。针对非平面形状的细长体飞行器自由边界条件下的热模态特性开展了研究。通过研究模拟气动加热条件的圆筒形加热笼、模拟自由边界的耐高温柔性支撑、非接触激光多普勒测振、耐高温激振杆激励等试验方法,获得了细长体结构自由边界条件下随温度变化的前3阶模态变化情况。结果表明:对此类薄壁长圆筒类结构,温度升高对模态频率影响可以超过6Hz。开展有限元仿真,并与试验取得的热模态结果的变化规律进行对比。结果表明:建立考虑温度对结构弹性模量、热应力影响的壳单元模型,能够较好地预测出前3阶模态频率在全部受热时间范围内的最大下降量,可为高超声速飞行器控制系统设计时的拉偏范围提供参考。As the use of more high temperature/high load durable materials in modern hypersonic vehicles requires load durable structures to work in increasingly higher temperature,much attention has been paid to thermo-modal characteristics of structures.This paper discusses the thermo-modal characteristics of a spindly vehicle with a non-planar shape in free flight boundary conditions.A cylindrical cage for aerodynamic heating simulation is studied.A free flight and flexible supporting boundary which is high temperature durable is simulated,a non-contact vibration measurement is conducted using laser Doppler,and a high temperature durable excitation pole is excited,obtaining the first 3-order modal variation of the spindly vehicle under free boundary conditions.The results show that temperature elevation can result in a 6 Hz decrease of the natural frequencies of such a thin and long cylindrical structure.A comparison of FE simulation results with test results shows that the shell element model which considers the effect of temperature on elastic module and thermo-stress of the structure can well predict the maximum decrease of the first 3-order natural frequencies in aerodynamic heating,and can thus provide some reference for the margin of the design of control system of hypersonic vehicles.

关 键 词：气动加热模拟装置 弹性支撑边界 激光测振 热模态 模态频率 

分 类 号：V216.2[航空宇航科学与技术—航空宇航推进理论与工程] V216.4