Hydrodynamics of Fractal Aggregates with Radially Varying Permeability.
Hydrodynamics of Fractal Aggregates with Radially Varying Permeability.
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DOI：
10.1006/jcis.1996.0005
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发表时间：
1996-01
影响因子：
9.9
通讯作者：
Veerapaneni;Wiesner
中科院分区：
文献类型：
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作者：
Veerapaneni;Wiesner
分形聚集体与径向变化的渗透率的流体动力学性质的研究方面的两个参数：半径的等效固体球经历相同的阻力的聚集体（欧米茄 * 聚集体半径）和流体收集效率（η）的聚集体。流体流过聚集体的阻力预计将随着分形维数的增加而增加，而流体收集效率预计将降低。它示出的分形聚集体上的流体拖曳力的合理估计可以通过分配一个恒定的体积平均孔隙率的聚集体，并使用在文献中的任何表达式具有均匀的渗透性的聚集体。这两个流体动力学参数，欧米茄和η，是用来修改现有的固体球之间的相互作用的表达式，占多孔性的聚集体，从而计算相互作用的聚集体的碰撞率内核。所提出的模型预测的聚集体的流体动力学半径的比，其回转半径是在合理的协议与文献中报道的实验值。
Hydrodynamic properties of fractal aggregates with radially varying permeability are investigated in terms of two parameters: radius of equivalent solid sphere experiencing the same drag as the aggregate (Omega*radius of aggregate) and fluid collection efficiency (eta) of the aggregate. Resistance to the fluid flow through the aggregate is predicted to increase with increasing fractal dimension, while the fluid collection efficiency is expected to decrease. It is shown that a reasonable estimate of the fluid drag force on a fractal aggregate may be obtained by assigning a constant volume-averaged porosity to the aggregate and using any of the expressions available in the literature for aggregates with uniform permeability. The two hydrodynamic parameters, Omega and eta, are used to modify the existing expressions for interactions between solid spheres to account for the porous nature of aggregates and thus calculate the collision rate kernels for interacting aggregates. The ratio of hydrodynamic radius of an aggregate to its radius of gyration predicted by the proposed model was in reasonable agreement with an experimental value reported in the literature.