计入热梯度的圆环结构热致振动分析

Thermally induced vibration of a circular ring in consideration of the thermal gradient

大型空间可展开结构通常是由梁、环等组成的周期性连续体结构,当进出地球阴影时受到热冲击而导致热致结构振动。针对支撑天线反射面的环形桁架结构,基于等效的空间圆环力学模型研究热致振动问题。建立热-结构耦合作用模型,采用加权余量法获得近似解。通过Routh-Hurwitz判据,获得太阳辐射引起的热致振动稳定域。采用Fourier温度单元与结构有限元结合的方法对圆环的热冲击响应进行了数值仿真和验证。

Large space hoop structures are often simplified as space beams and circular rings to analytically investigate their thermally induced vibrations.For analysing the thermally induced vibration of hoop-truss structures used to support the antenna reflector,a coupled thermal-structural model for the space circular ring was developed.Its approximate solution was derived by the weighted residual method,based on that the simplified system equation in state space was established.The stable region of the thermally induced vibration considering the effects of the incident angle of solar radiation and the structural damping was obtained by Routh-Hurwitz criterion.Finally,using an analysis method combining the Fourier thermal finite element and the structural finite element,the dynamic responses subjected to thermal shock were simulated numerically and the results were verified for different cases.