Axial compression-induced wrinkles on a core-shell soft cylinder: Theoretical analysis, simulations and experiments
Axial compression-induced wrinkles on a core-shell soft cylinder: Theoretical analysis, simulations and experiments
复制标题
核壳软圆柱上的轴向压缩引起的皱纹：理论分析、模拟和实验
DOI：
10.1016/j.jmps.2014.09.005
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发表时间：
2014-12-15
影响因子：
5.3
通讯作者：
Ma, Kang
中科院分区：
文献类型：
--
作者：
Zhao, Yan;Cao, Yanping;Ma, Kang
通过实验、计算和理论相结合的方法，研究了轴压作用下软核支撑圆柱壳的表面起皱问题。实验结果表明，当表层与芯层的模量比较小时，系统的分叉后变形模式为轴对称，而当模量比较大时，系统的分叉后变形模式为非轴对称。我们的非线性有限元模拟证实了这一实验发现。基于Koiter的弹性稳定性理论进行了理论分析，揭示了形态演变现象的机制。临界屈曲分析表明，第一分叉模式是轴对称的任意模量比的壳芯。分叉后分析表明，当弹性模量比足够大时，系统将演化为类菱形模态，当弹性模量比小于某一临界值时，系统将保持轴对称模态。研究结果可用于指导圆柱面在压缩条件下可控表面褶皱的生成。此外，这里提出的分析方法可以用来理解在一些自然系统中观察到的由差异生长等产生的生物模式。(C)2014爱思唯尔有限公司版权所有。
Surface wrinkling of a cylindrical shell supported by a soft core subjected to axial compression is investigated via combined experimental, computational and theoretical efforts. Our experiments show that the post-bifurcation deformation mode of the system is axisymmetric when the modulus ratio of the surface layer to the core is small while a non-axisymmetric wrinkling pattern appears when the modulus ratio is large. Our nonlinear finite element simulations have confirmed this experimental finding. A theoretical analysis based on Koiter's elastic stability theory is carried out to reveal the mechanisms underpinning the phenomenon of morphological evolution. The critical buckling analysis shows that the first bifurcation mode is axisymmetric for arbitrary modulus ratios of the shell to the core. Post-bifurcation analysis reveals that the system will evolve into a diamond-like mode when the modulus ratio is large enough but keep the axisymmetric mode if the modulus ratio is smaller than a critical value. The results can guide the creation of controlled surface wrinkles on a cylindrical surface under compression. Besides, the analysis approach presented here may be adopted to understand the wrinkling patterns observed in some natural systems generated by, for instance, differential growth. (C) 2014 Elsevier Ltd. All rights reserved.