考虑黏弹性的簧片单元力学性能分析

Analysis of Mechanical Properties of Tape-spring With Viscoelastic Effects

为提高空间可展簧片铰链的运行稳定性和可靠性,研究了材料黏弹性对其弯曲折叠过程中的应变能、临界弯矩和稳态弯矩的影响.利用广义Maxwell黏弹性模型建立了考虑黏弹性的簧片单元力学模型,采用数值模拟方法探究了外界温度、折叠速率、Prony常数、松弛时间对簧片单元应变能、临界弯矩和稳态弯矩的影响规律.结果表明:在折叠过程中,随着Prony常数,松弛时间和折叠速度的减小,簧片单元应变能、临界弯矩和稳态弯矩均有所减小.随着温度的增加,簧片单元应变能、临界弯矩和稳态弯矩均呈现不同程度的减小.在装载过程中,簧片单元的稳态弯矩和应变能随着装载时间的增加而减小并趋于稳定.本研究对于提高空间可展结构的设计可靠性提供了一定的依据.

To improve the operation stability and reliability, the effects of viscoelasticity for the tape spring on the strain energy, critical moment and steady moment exhibiting in the folding process were studied. The generalized Maxwell viscoelastic model was used to establish the mechanical model of the tape spring and numerical simulation was carried out to investigate the influence of different folding rates, temperatures, Prony series and relaxation times on critical moment, steady moment and strain energy in the bending process. Results show that the strain energy, critical moment and steady moment of the tape spring in the folding process cut down with decreasing folding rate, Prony series and relaxation time and increasing temperature. The strain energy and steady moment of the tape spring are reduced with the increase of the stowage time and gradually reach a constant value. This research has an important theoretical reference for improving the design reliability of space deployable structures.