Representation of generally mixed multivariate aerosols by the quadrature method of moments:II.Aerosol dynamics

摘要

The quadrature method of moments (QMOM) is extended to generally mixed multicomponent particle populations using principal component analysis (PCA).The resulting PCA-QMOM provides a versatile method for moment closure illustrated for generally mixed,multivariate,particle populations evolving under condensation,coagulation,sintering,and simultaneous processes.The method is illustrated using a 2~h-point quadrature version of the PCA-QMOM,where h is the number of coordinate dimensions,developed in the preceding paper (Paper I).Calculations for multiple particle populations interacting through coagulation are also presented.A theory is developed for the time-dependence of the covariance matrix of a multicomponent particle population evolving under a size-independent coagulation rate.It is found that the rank of the h x h covariance matrix,for h components,approaches unity at long time as the particle population evolves to an internally mixed,self-preserving size distribution state.