Taglienti Diego, Guglietta Fabio, Sbragaglia Mauro
<a href="https://ror.org/025rrx658">Department of Physics & INFN</a>, <a href="https://ror.org/02p77k626">Tor Vergata University of Rome</a>, Via della Ricerca Scientifica 1, 00133 Rome, Italy.
Phys Rev E. 2024 Jul;110(1-2):015302. doi: 10.1103/PhysRevE.110.015302.
We develop a numerical method for simulating the dynamics of a droplet immersed in a generic time-dependent velocity gradient field. This approach is grounded on the hybrid coupling between the lattice Boltzmann (LB) method, employed for the flow simulation, and the immersed boundary (IB) method, utilized to couple the droplet with the surrounding fluid. We show how to enrich the numerical scheme with a mesh regularization technique, allowing droplets to sustain large deformations. The resulting methodology is adapted to simulate the dynamics of droplets in homogeneous and isotropic turbulence, with the characteristic size of the droplet being smaller than the characteristic Kolmogorov scale of the outer turbulent flow. We report statistical results for droplet deformation and orientation collected from an ensemble of turbulent trajectories, as well as comparisons with theoretical models in the limit of small deformation.
我们开发了一种数值方法，用于模拟浸没在一般随时间变化的速度梯度场中的液滴动力学。这种方法基于用于流动模拟的格子玻尔兹曼（LB）方法与用于将液滴与周围流体耦合的浸入边界（IB）方法之间的混合耦合。我们展示了如何用网格正则化技术丰富数值格式，使液滴能够承受大变形。所得方法适用于模拟液滴在均匀各向同性湍流中的动力学，液滴的特征尺寸小于外部湍流的特征科尔莫戈罗夫尺度。我们报告了从一组湍流轨迹中收集的液滴变形和取向的统计结果，以及在小变形极限下与理论模型的比较。
