论文标题
巨大的主动湍流中的巨型涡流动力学
Giant vortex dynamics in confined active turbulence
论文作者
论文摘要
我们报告了在受限域中新的主动湍流状态的数值证据。通过对圆形几何形状中致密细菌悬浮液的碳碳-TU-SWIFT-HOHENBERG模型的广泛数值模拟，我们发现了形成一个稳定的有序状态，其中角动量对称性损坏了。这是通过将湍流样流动到域大小的单个巨大涡流中的自我组织来实现的。巨大的涡流被靠近边界的环形区域所包围，其特征是小规模的径向涡度条纹。发现涡旋的平均径向速度曲线与简单的分析预测一致。我们还提供了与数值发现相当的合适实验设置的时间和空间尺度的估计。
We report the numerical evidence of a new state of active turbulence in confined domains. By means of extensive numerical simulations of the Toner-Tu-Swift-Hohenberg model for dense bacterial suspensions in circular geometry, we discover the formation a stable, ordered state in which the angular momentum symmetry is broken. This is achieved by self-organization of a turbulent-like flow into a single, giant vortex of the size of the domain. The giant vortex is surrounded by an annular region close to the boundary, characterized by small-scale, radial vorticity streaks. The average radial velocity profile of the vortex is found to be in agreement with a simple analytical prediction. We also provide an estimate of the temporal and spatial scales of a suitable experimental setup comparable with our numerical findings.
