论文标题
粒状材料中依赖速率的阻力不稳定性
Rate-dependent drag instability in granular materials
论文作者
论文摘要
我们研究导致颗粒材料中抗力量波动较大的条件。该研究基于一组实验阻力测试，该试验涉及垂直通过无内核颗粒材料拉动板。与先前的观察结果一致，当将板以低速度拉出时，阻力会显示出明显的突然下降至60％。我们进一步发现，这种不稳定在较高的拔出速度和表面附近消失。我们从经验上表征了这些波动的频率和振幅，发现这些特性与经典的棒状滑动动力学不一致。因此，我们提出了一种可以解释这些力波动的替代物理机制。
We investigate the conditions leading to large drag force fluctuations in granular materials. The study is based on a set of experimental drag tests, which involve pulling a plate vertically through a cohesionless granular material. In agreement with previous observations, drag force exhibits significant and sudden drops -up to 60%- when the plate is pulled out at low velocities. We further find that this instability vanishes at higher pullout velocities and near the surface. We empirically characterise the frequency and amplitude of these fluctuations and find that these properties are not consistent with a classical stick-slip dynamics. We therefore propose an alternative physical mechanism that can explain these force fluctuations.
