Direct expansion method of moments with n/3th moments for nanoparticle Brownian coagulation in the free molecule regime
International Journal of Numerical Methods for Heat & Fluid Flow
ISSN: 0961-5539
Article publication date: 5 January 2015
Abstract
Purpose
The purpose of this paper is to develop new types of direct expansion method of moments (DEMM) by using the n/3th moments for simulating nanoparticle Brownian coagulation in the free molecule regime. The feasibilities of new proposed DEMMs with n/3th moments are investigated to describe the evolution of aerosol size distribution, and some of the models will be applied to further simulation of physical processes.
Design/methodology/approach
The accuracy and efficiency of some kinds of methods of moments are mainly compared including the quadrature method of moments (QMOM), Taylor-expansion method of moments (TEMOM), the log-normal preserving method of moments proposed by Lee (LMM) and the derived DEMM in this paper. QMOM with 12 quadrature approximation points is taken as a reference to evaluate other methods.
Findings
The newly derived models, namely DEMM(4/3,4) and DEMM(2,6), as well as the previous DEMM(2,4), are considered to be qualified models due to their high accuracy and efficiency. They are confirmed to be valid and alternative models to describe the evolution of aerosol size distribution for particle dynamical process involving the n/3th moments.
Originality/value
The n/3th moments, which have clear physical interpretations when n stands for first several integers, are first introduced in the DEMM method for simulating nanoparticle Brownian coagulation in the free molecule regime.
Keywords
Acknowledgements
This work has been financially supported by the National Natural Science Foundation of China (No.11132008).
Citation
Fangyang, Y. and Zhongli, C. (2015), "Direct expansion method of moments with n/3th moments for nanoparticle Brownian coagulation in the free molecule regime", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 25 No. 1, pp. 86-97. https://doi.org/10.1108/HFF-04-2013-0120
Publisher
:Emerald Group Publishing Limited
Copyright © 2015, Emerald Group Publishing Limited