细颗粒间相互作用力的研究

对微米、近亚微米尺度的细颗粒间相互作用过程的显微观察发现,细颗粒间具有"吸引-旋绕-排斥"的相互作用行为.受力分析表明,包含范德华力、静电库仑力和电像力的传统颗粒间作用力模型不能解释这种相互作用行为.根据细颗粒的荷电特性,提出细颗粒间还具有诱导偶极子作用力.通过引入偶极子作用力改进了细颗粒间作用力模型,利用新的模型对细颗粒间相互作用进行了模拟,得到了和实验相同的相互作用行为,并且对影响细颗粒相互作用的参数进行了分析.提出投入大颗粒和增加外静电场等都是促进颗粒凝并的有效措施.

MECHANISM OF INTERACTIONS BETWEEN FINE PARTICLES

The interactions between micron or near-submicron particles behaved as "attracting- revolving-repulsing" characteristics. The conventional inter-particle force model, including van der Waals force, Coulomb force and image force, could not explain these interaction behaviors. The forces between induced dipoles were proposed and added to modify the inter-particle force model. The simu- lations of particle interactions by the new force model agreed well with the experimental results. The analyses based on the new model showed that the influential parameters in the interactions included particle diameters, the initial relative locations, and the initial relative velocity. Applying external electrical field and inputting larger particles are the effective measures to enhance the aggregation of fine particles.