Article

The time second-order characteristic fem for nonlinear multicomponent aerosol dynamic equations in environment

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Abstract

An efficient time second-order characteristic finite element method for solving the nonlinear multi-component aerosol dynamic equations is developed. While a highly accurate characteristic method is used to treat the advection multi-component condensation/evaporation process, a time high-order extrapolation along the characteristics is applied to approximate the nonlinear multi-component coagulation terms. The scheme is of second order accuracy in time for the multi-component problems. We study the theoretical analysis and obtain the time secondorder error estimate of the scheme. Numerical experiments are further given to confirm the theoretical results. The dynamic behaviours of multi-component aerosol distributions are also simulated for the multi-component aerosol problems of aerosol water, black carbon and sulfate components with different tri-modal log-normal initial distributions.

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... For atmospheric aerosols, coagulation and condensation are the most important processes, as many of the properties of aerosols (light scattering, radioactivity and capturing strategies) are dependent on the size and compositional distributions of particles. Furthermore, coagulation and condensation processes are very important phenomena to the evolution of particle size and compositional distributions [11][12][13] . Therefore, these two processes have been widely explored in studies on particle size and compositional distributions. ...
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