论文标题
共振的上升和下沉：探测旋转动力学对浮力球的关键作用
Rising and Sinking in Resonance: Probing the critical role of rotational dynamics for buoyancy driven spheres
论文作者
论文摘要
我们提出了球形颗粒在静止流体中升高和沉降的实验结果。施加一个良好的质量偏移中心，使我们能够通过将固有的旋转时间尺度引入问题来选择性地改变旋转动力学。结果甚至对偏移程度的偏移也很敏感，这本身就是一个实际相关的参数。我们进一步发现，在旋转与涡流脱落时间尺度的一定比例（捕获弗洛德型相似性）中，共振现象所设定。尽管这是起源的旋转效应，但它也会强烈影响翻译振荡频率和振幅，最重要的是，最重要的是，最重要的是。该观察结果同样适用于重和轻球，尽管我们提供了略有不同的特征，我们提供了解释。我们的发现突出了在尝试理解和分类上升和沉降球的路径属性时考虑旋转参数的需求。
We present experimental results for spherical particles rising and settling in a still fluid. Imposing a well-controlled center of mass offset enables us to vary the rotational dynamics selectively by introducing an intrinsic rotational timescale to the problem. Results are highly sensitive even to small degrees of offset, rendering this a practically relevant parameter by itself. We further find that for a certain ratio of the rotational to a vortex shedding timescale (capturing a Froude-type similarity) a resonance phenomenon sets in. Even though this is a rotational effect in origin, it also strongly affects translational oscillation frequency and amplitude, and most importantly the drag coefficient. This observation equally applies to both heavy and light spheres, albeit with slightly different characteristics for which we offer an explanation. Our findings highlight the need to consider rotational parameters when trying to understand and classify path properties of rising and settling spheres.
