New Expression for Collision Efficiency of Spherical Nanoparticles in Brownian Coagulation
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摘要: 研究了邻苯二甲酸二辛酯纳米颗粒在Brown凝并过程中的碰撞效率.在考虑Stokes阻力、润滑力、van der Waals力和颗粒变形恢复力的情况下推导了一组碰撞方程,通过数值求解这组方程,得到了当颗粒半径从50 nm到500 nm变化时,颗粒碰撞效率和半径之间的关系,计算得到的结果和实验结果符合较好.计算结果表明,在颗粒半径为50 nm到500 nm的情况下,颗粒的碰撞效率随颗粒半径的增加而减小.基于计算结果,提出了颗粒碰撞效率的新表达式.Abstract: The collision efficiency of dioctyl phthalate nanoparticles in the Brownian coagulation was studied. A set of collision equations were solved numerically to find the relationship between the collision efficiency and the particle radius varying from 50 nm to 500 nm in the presence of Stokes resistance, lubrication force, vander Waals force and elastic deformation force. The calculated results are in agreement with the expermiental ones qualitatively. The results show that the collision efficiency decreases with the increase of particle radius in the range of 50 nm to 500 nm. Based on the numerical data a new express ion for collision efficiency was presented.
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Key words:
- nanoparticles /
- Brownian coagulation /
- collision efficiency /
- Stokes resistance /
- lubrication force
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