Yang Lingqi, Yin Huiming
Columbia University, 500 West 120th Street, New York, New York 10027, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Sep;90(3):033311. doi: 10.1103/PhysRevE.90.033311. Epub 2014 Sep 24.
A parametric study on the simulation of a single aluminum (Al) particle settling in water is conducted using various sets of interactive parameters between Al and water particles, so that a systematic method can be established to describe the hydrodynamic interaction between an Al particle and the fluid in a large range of particle sizes. The force parameters and the cutoff have been correlated to the terminal settling velocity of the Al particle in the dissipative particle dynamics simulation, so that the classic Stokes' law can be used to determine those parameters. Two empirical equations are developed to calculate the minimum repulsive force parameter in terms of the number density and radius, respectively. In addition, the correlation between the cutoff and the Al particle radius has been obtained by linear curve fitting. The radial distribution functions of Al and water particles are computed to examine the relative spacing among solid and fluid particles. The present approach is general and can also be extended to study particle motion of other types of particles and fluids. This study will be a baseline for the investigation of multiple particles settling in a viscous fluid.
利用铝（Al）颗粒与水颗粒之间的各种交互参数集，对单个铝颗粒在水中沉降的模拟进行了参数研究，以便建立一种系统方法来描述在大范围粒径下铝颗粒与流体之间的流体动力相互作用。在耗散粒子动力学模拟中，力参数和截止值已与铝颗粒的终端沉降速度相关联，从而可以使用经典的斯托克斯定律来确定这些参数。分别根据数密度和半径推导出两个经验方程来计算最小排斥力参数。此外，通过线性曲线拟合得到了截止值与铝颗粒半径之间的相关性。计算了铝颗粒和水颗粒的径向分布函数，以研究固体和流体颗粒之间的相对间距。本方法具有通用性，也可扩展用于研究其他类型颗粒和流体的颗粒运动。本研究将为研究粘性流体中多个颗粒沉降提供基线。
