Serra T, Casamitjana X
Campus de Montilivi, University of Girona, Girona, 17071, Spain
J Colloid Interface Sci. 1998 Oct 15;206(2):505-511. doi: 10.1006/jcis.1998.5714.
A particle size analyzer together with a video camera has been used to investigate the structure of the aggregates during the process of aggregation and breakup of particles in a shear flow induced by means of a Couette-flow system. Three different values for the shear rate have been used (25, 32, and 50 s-1). The initial volume fraction of the particles was phi0 = 5.0 x 10(-5). Different fractal dimensions (D3), D2, D1, and Dpf), the shape factor (xi2), and the aspect ratio (AR) have been used to characterize the structure of the aggregates. During the process of aggregation, no significant changes in the fractal dimensions, shape factor, and aspect ratio were found. The high values obtained for D3 (D3 = 2.2) and D2 (D2) = 1.98) show us the high compactness of the flocs. Also, values of the fractal dimension and shape factor have been found to not depend on the shear rate. Copyright 1998 Academic Press.
利用粒度分析仪和摄像机研究了在库埃特流系统产生的剪切流中颗粒聚集和破碎过程中聚集体的结构。使用了三种不同的剪切速率值（25、32和50 s-1）。颗粒的初始体积分数为phi0 = 5.0 x 10(-5)。采用不同的分形维数（D3）、D2、D1和Dpf）、形状因子（xi2）和纵横比（AR）来表征聚集体的结构。在聚集过程中，未发现分形维数、形状因子和纵横比有显著变化。D3（D3 = 2.2）和D2（D2 = 1.98）的高值表明絮凝物具有高致密性。此外，还发现分形维数和形状因子的值不依赖于剪切速率。版权所有1998年学术出版社。
