Effect of particle wettability on particle-particle adhesion of colliding particles through droplet
Effect of particle wettability on particle-particle adhesion of colliding particles through droplet
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DOI：
10.1016/j.powtec.2016.08.066
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发表时间：
2016-11
影响因子：
5.2
通讯作者：
Hiroyuki Kan;Hideya Nakamura;S. Watano
中科院分区：
文献类型：
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作者：
Hiroyuki Kan;Hideya Nakamura;S. Watano
在湿法造粒过程中，由于颗粒的连续运动，颗粒之间形成的液桥不是静态的，而是动态的。因此，通过动态液桥来理解颗粒间的粘附性是一个重要的问题。本文采用动态液桥对颗粒-颗粒粘附性进行了直接数值模拟。模拟了两个相互碰撞的颗粒通过颗粒表面液滴的粘附性。特别研究了颗粒润湿性对颗粒附着的临界速度(即两个碰撞颗粒的粘附性)的影响。结果表明，颗粒粘着的临界速度随颗粒润湿性的变化呈非单调变化。临界速度随接触角的增大而出现局部极大值，静液桥力随接触角的增大而单调减小。结果表明，液桥变形和瞬时液桥力的共同作用导致了颗粒润湿性的非单调依赖。
In wet granulation processes, a liquid bridge formed between particles is not static but dynamic due to continuous motion of the particles. Therefore, understanding of the particle-particle adhesion by a dynamic liquid bridge is an important issue. We here conducted a direct numerical simulation of the particle-particle adhesion by a dynamic liquid bridge. The particle-particle adhesion of two colliding particles through a droplet on a particle surface was simulated. In particular, effect of particle wettability on a critical velocity for the particle adhesion (i.e., adhesiveness of the two colliding particles) was investigated. It was found that the critical velocity for the particle adhesion non-monotonically changed with the particle wettability. The critical velocity exhibited a local maximum with an increase in the contact angle, while the static liquid bridge force monotonically decreases with an increase in the contact angle. We revealed that a combined effect of the liquid bridge deformation and instantaneous liquid bridge force results in the non-monotonic dependence on the particle wettability.