Aggregate size distribution evolution for Brownian coagulation—sensitivity to an improved rate constant
- 作者：Zurita-Gotor ; M. ; Rosner ; D.E.
- 关键词：Fractal-like aggregates ; Collision rate ; Brownian coagulation ; Self-preserving aggregate size distribution ; Monte Carlo ; Quadrature method of moments ; Nanoparticle aerosols
- 刊名：Journal of Colloid and Interface Science
- 出版年：2004
- 期刊代码：125_00219797
- 类别：ch
- 出版时间：June 15, 2004
- 卷：274
- 期：2
- 页码：502-514
- 文件大小：360 K
摘要
Brownian motion causes small aggregates to encounter one another and grow in gaseous environments, often under conditions in which the coalescence rate (say, spheroidization by “sintering”) cannot compete. The polydisperse nature of the aerosol population formed by this mechanism is typically accounted for by formulating an evolution equation for the joint PDF of the state variables needed for describing individual particles. In the simple case of fractal-like aggregates (prescribed morphology and state, characterized just by the number of aggregated spherules, or total aggregate volume), we use the quadrature method of moments and Monte Carlo simulations to show that recent improvements in the laws governing free molecule regime coagulation frequency (rate “constant”) of these aggregates cause systematic changes in the shape of the asymptotic aggregate size distribution, with significant implications for the light-scattering power and inertial impaction behavior of such aggregate populations.