摘要
高超声速飞行器在巡航和再入过程中,面临着严酷的气动力和热载荷复合环境。梁结构作为飞行器的基本构件,掌握它的气动热弹性动力学特性是开展其动态化设计及优化的基础。以多孔FGM梁为研究对象,应用超声速活塞理论和热弹性理论考虑气动力和热载荷的影响,基于一阶剪切变形理论和von-Karman大变形理论,根据能量法建立了一般约束边界下多孔FGM(functionally graded material)梁的气动热弹性非线性动力学模型,并利用Newmark法联合牛顿迭代法求解系统的动力学响应。通过将该模型计算所得的结果和文献结果对比,验证了该方法的准确性。在此基础上,通过数值算例分析了边界约束、FG材料指数、温度和孔隙率等参数对FGM梁动力学特性的影响规律。研究结果将为多孔FGM梁的动态化设计及优化提供理论参考依据。
Aerospace flight vehicles are always subjected to severe environment including aerodynamic and thermal loads during the cruise and re-entry.Understanding of the aero-thermo-elastic characteristics of beam structures,which are served as the basic component of aerospace flight vehicles,is the basic to perform dynamic design and optimization of structures.The effects of thermal load and aerodynamic pressure were taken into consideration by using the thermo-elastic theory and the supersonic piston theory,respectively.The first-order shear deformation theory(FSDT)combined with von-Karman nonlinear strain-displacement relation was adopted to derive the governing equations of the system.The dynamic responses of the system were obtained by using the Newmark method combined with the Newton iteration method.By comparing the dynamic results obtained from the proposed model and those from the literature,the accuracy of the proposed method was validated.Finally,by performing the parametric analysis,the effects of the constraint,material constituent,thermal load and porosity ratio on the vibration and flutter characteristics of the beam structures were investigated.The results provide theoretical reference for the dynamic design and optimization of porous FGM beams.
作者
周凯
倪臻
华宏星
ZHOU Kai;NI Zhen;HUA Hongxing(State Key Laboratory of Mechanical System and Vibration,Shanghai JiaoTong University,Shanghai 200240,China;Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration,Shanghai 200240,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2021年第20期34-41,共8页
Journal of Vibration and Shock
基金
中国博士后科学基金(2020M671108)。
关键词
功能梯度梁
孔隙
非线性振动
气动热弹性
一般约束边界
functionally graded material beam
porosity
nonlinear vibration
aero-thermo-elastic
general boundary conditions
