Experimentalphysik V, Universität Bayreuth, 95440, Bayreuth, Germany.
Sci Rep. 2017 Jun 15;7(1):3613. doi: 10.1038/s41598-017-03844-0.
Density-wave fronts in a vibrofluidized wet granular layer undergoing a gas-liquid-like transition are investigated experimentally. The threshold of the instability is governed by the amplitude of the vertical vibrations. Fronts, which are curved into a spiral shape, propagate coherently along the circular rim of the container with leading edges. They are stable beyond a critical distance from the container center. Based on an analysis of the emerging time and length scales, we propose a model for the pattern formation by considering the competition between the time scale for the condensation of wet granular particles from a gas-like state and that of the energy injection resisting this process.
在经历气液相似转变的振动流化湿颗粒层中，研究了密度波前。不稳定性的阈值由垂直振动的振幅控制。前缘呈螺旋形弯曲，沿着容器的圆形边缘以领先边缘的方式协调传播。它们在远离容器中心的临界距离之外是稳定的。基于对新兴时间和长度尺度的分析，我们提出了一个模型，通过考虑从气体状态凝结湿颗粒的时间尺度与抵抗该过程的能量注入的时间尺度之间的竞争来考虑图案形成。
