Rémond Théophile, Dolique Vincent, Vittoz Franck, Antony Sheedev, Rinaldi Renaud G, Manin Lionel, Géminard Jean-Christophe
LPENSL, CNRS, UMR 5672, ENS de Lyon, F-69342 Lyon, France.
LaMCoS, CNRS, UMR 5529, INSA-Lyon, Université de Lyon, F-69621 Villeurbanne, France.
Phys Rev E. 2022 Jul;106(1-1):014207. doi: 10.1103/PhysRevE.106.014207.
We report on the dynamical buckling of a spherical shell (a table-tennis ball) impinging in normal incidence on a rigid surface (a glass plate). Experimentally, we observe and decipher the geometrical characteristics of the shell profile in the contact region along with global metrics such as the contact duration and the coefficient of restitution of the linear velocity. We determine, in particular, the onset of the ball buckling instability. We find that, just like in quasi-statics, the shell buckles when the crushing exceeds about twice the thickness of the shell. In addition, for launching conditions resulting in the ball elastic buckling, a drop in the restitution coefficient is observed. A companion numerical finite elements study is set to monitor the different sources of energy and reveals that the added energy loss is mainly due to the friction between the shell surface and the solid substrate.
我们报告了一个以垂直入射角撞击刚性表面（玻璃板）的球壳（乒乓球）的动态屈曲情况。通过实验，我们观察并解析了接触区域内球壳轮廓的几何特征以及诸如接触持续时间和线速度恢复系数等全局度量。我们特别确定了球的屈曲不稳定性的起始点。我们发现，与准静态情况一样，当挤压超过球壳厚度的两倍左右时，球壳会发生屈曲。此外，对于导致球弹性屈曲的发射条件，观察到恢复系数下降。同时开展了一项配套的数值有限元研究，以监测不同的能量来源，并揭示额外的能量损失主要是由于球壳表面与固体基板之间的摩擦。
