Wrinkling phenomena control the surface morphology of many technical and biological systems. While primary wrinkling has been extensively studied, experimentally, analytically and computationally, higher-order instabilities remain insufficiently understood, especially in systems with stiffness contrasts well below 100. Here, we use the model system of an elastomeric bilayer to experimentally ch...

Compressing a thin elastic film attached to a thick compliant substrate can lead to buckling instability. Two commonly observed buckling modes, buckle-delamination and wrinkling, have each been analyzed separately in previous studies. Recent experiments have observed that the two modes can co-exist and co-evolve. In this paper, by analytical and finite element methods, we present a study on con...

A healthy 23-year-old woman presented with a six-month history of white lesions on her palms. The lesions would swell after being in water for 15 minutes and return to baseline 10–15 minutes after drying. The patient did not take medications except for oral contraceptive pills, and she was not aware of a family history of similar complaints. Physical examination showed white, slightly transluce...

Mechanics of tympanic membrane (TM) is crucial for investigating the acoustic transmission through the ear. In this study, we studied the wrinkling behavior of tympanic membrane when it is exposed to mismatched air pressure between the ambient and the middle ear. The Rayleigh-Ritz method is adopted to analyze the critical wrinkling pressure and the fundamental eigenmode. An approximate analytic...

Wrinkling and fracture are the important defects in deep drawing operation, which can be prevented using blank holding force (BHF) which has to be optimized as lower BHF promotes wrinkles formation and higher BHF promotes fracturing. Hence the limits of wrinkling and fracture have to be established. These limits depend on various tooling and process parameters. In this work the effect of toolin...

In this paper, the anisotropic thermal conductivity characteristics of graphene wrinkles are observed for the first time using a non-equilibrium molecular dynamics method. Our results reveal that the wrinkling level has little effect on the thermal conductivity along the wrinkling direction. However, the wrinkling level plays an important role in the reduction of thermal conductivity along the ...

We examine the buckling shape and critical compression of confined inhomogeneous composite sheets lying on a liquid foundation. The modes are controlled by bending stiffness sheet,...

We present a method to control wave propagation in highly deformable layered media by utilizing elastic insta-bility-induced wrinkling of interfacial layers. The onset of a wrinkling instability in initially straight interfacial layersoccurs when a critical compressive strain or stress is achieved [1]. Further compression beyond the critical strainleads to an increase in the wri...

A method to simulate orthotropic behaviour in thin shell finite elements is proposed. The approach is based on the transformation of shape function derivatives, resulting in a new orthogonal basis aligned to a specified preferred direction for all elements. This transformation is carried out solely in the undeformed state leaving minimal additional impact on the computational effort expended to...