Code for the cluster dichotomy model

The stability of colloid is closely related to the aggregation of colloidal particles and the dispersion of clusters in the system. Because aggregation changes the original state of the sol, previous studies have paid more attention to the aggregation process of the colloid. In fact, aggregation process and dispersion process coexist. The Cluster-Cluster Aggregation model has been widely used to simulate the process of colloidal agglomeration. In the aspect of cluster dispersion, people pay more attention to the simulation of cluster dispersion caused by external forces (such as shear force). In the actual system, the sudden decrease of electrolyte concentration leads to the increase of electrostatic repulsion between colloidal particles, resulting in the disintegration of the clusters. Inspired by the dimerization process of the traditional Cluster-Cluster Aggregation model, we previously proposed a dichotomy model to simulate the dispersion process of colloidal clusters. Here, we provide Java code for the dichotomy model, which can simulate dispersion caused by external forces and internal forces. This paper further elaborates the key points of the dichotomy model, mainly including: the definitions of the relevant probabilities involved in the dichotomy model, the data structures of particle, cluster and cube, and the functions of the relevant parameters related to the dichotomy model. Furthermore, the cluster's characteristics of erosion dispersion and collapse dispersion are studied respectively.

胶体的稳定性与胶体颗粒的聚集行为及体系内团簇的分散状态密切相关。由于聚集过程会改变溶胶的原始状态，过往研究多聚焦于胶体的聚集过程。事实上，聚集与分散过程是共存的。团簇-团簇聚集（Cluster-Cluster Aggregation）模型已被广泛用于模拟胶体团聚过程。在团簇分散领域，现有研究多关注外力（如剪切力）诱导的团簇分散模拟。而在实际体系中，电解质浓度的骤降会导致胶体颗粒间的静电斥力增大，进而引发团簇解体。受传统团簇-团簇聚集模型的二聚化过程启发，我们此前提出了一种二分模型（dichotomy model）以模拟胶体团簇的分散过程。本文提供了该二分模型的Java代码，其可模拟外力与内力共同诱导的分散行为。本文进一步阐述了二分模型的核心要点，主要包括：二分模型涉及的相关概率定义、颗粒、团簇与立方单元的数据结构，以及二分模型相关参数的作用。此外，本文还分别研究了团簇的侵蚀分散与崩塌分散特性。