Sedimentation of Snow Particles in Still Air in Stokes Regime
Sedimentation of Snow Particles in Still Air in Stokes Regime
复制标题
斯托克斯流态下静止空气中雪粒的沉降
DOI：
10.1029/2020gl087832
复制
发表时间：
2020
影响因子：
5.2
通讯作者：
M. Holzner
中科院分区：
文献类型：
--
作者：
Till Zeugin;Quirine Krol;I. Fouxon;M. Holzner
我们计算从积雪样本的微计算机断层扫描数据和相场模型获得的真实三维雪颗粒形状的电阻矩阵。利用这些阻力矩阵，我们计算了Stokes区中静止空气中颗粒的沉降。我们发现，粒子获得优先取向和运动模式是漂移或螺旋。简单的法律，平均阻力和旋转扭矩系数的颗粒的球形度，建立导致一个新的制定雪粒子的平均终端速度。所提出的模型在静止空气中的Stokes区是有效的，对应于粒径达100 μm的颗粒，但可以合理地扩展到适度较高的雷诺数（100 μ m），并用于估计湍流条件下的平均沉降速度。虽然没有涵盖所有相关的大气条件，但我们的研究为未来解决更复杂的条件提供了基础。
We compute the resistance matrices of realistic 3‐D snow particle shapes obtained from microcomputed tomography data of snowpack samples and a phase field model. Using these resistance matrices, we calculate the sedimentation of the particles in still air in Stokes regime. We find that particles attain preferred orientations and the mode of motion is either drifting or spiraling. Simple laws, relating average drag and rotation torque coefficients to the particles' sphericity, are established which lead to a new formulation of a snow particle's average terminal velocity. The presented models are valid in Stokes regime in still air, corresponding to particle sizes up to ∼100 μm but can reasonably be extended to moderately higher Reynolds numbers (∼1 mm) and used for estimating mean settling velocity in turbulent conditions. Though not all relevant atmospheric conditions are covered, our study provides the basis for addressing more complex conditions in the future.
DOI：
10.1016/j.ijmultiphaseflow.2011.09.004
发表时间：
2012-03-01
影响因子：
3.8
作者：
Zastawny, Marian;Mallouppas, George;van Wachem, Berend
通讯作者：
van Wachem, Berend