92负刚度蜂窝结构压缩性能分析

A study on compression performance of negative stiffness honeycombs

为准确开展以黏弹性材料为载体的负刚度蜂窝结构数值模拟研究,提出一种基于黏弹性广义Maxwell模型的负刚度蜂窝结构压缩性能数值模拟法。进行了尼龙12的动态机械分析(DMA)测试,基于广义Maxwell模型拟合实测动态模量数据,得到反映尼龙12动态黏弹性的无量纲模量g_i和松弛时间τ_i。建立了负刚度蜂窝结构的有限元模型,基于实测的动态黏弹性参数,进行压缩性能的数值模拟研究,并同压缩试验结果进行比较,验证了数值模拟的准确性,利用数值模拟研究几何参数对结构压缩性能的影响规律。结果表明,基于黏弹性广义Maxwell模型的负刚度蜂窝结构数值模拟分析法可较准确模拟结构的压缩性能,为预测负刚度蜂窝结构的力学性能提供帮助。

In order to accurately study the numerical simulation of negative stiffness honeycombs with viscoelastic materials,a numerical simulation method that based on the viscoelastic generalized Maxwell model was proposed to simulate the compression properties of negative stiffness honeycombs.A dynamic mechanical analysis(DMA)testing was carried out for nylon 12,and the generalized Maxwell model was used to fit the measured data,thus,the dynamic modulus that reflected nylon 12 dynamic viscoelastic dimensionless modulus g i and relaxation timeτi were obtained.The finite element model of the negative stiffness honeycombs was established in Abaqus,and the dynamic viscoelastic parameters were applied to study the compression performance of the structure.At the same time,the compression experiment was carried out to verify the accuracy of the numerical simulation results.Finally,the influence of geometric parameters on compression the performance of structures was numerically simulated.The results show that the simulation analysis method based on the generalized viscoelastic Maxwell model can accurately simulate the compression performance of negative stiffness honeycombs,which provided help for the scientific prediction of the mechanical properties of negative stiffness honeycombs.