抄録
In order to investigate the nonsteady characteristics of acid rain formation by SO2-H2O2 absorption, a mathematical model has been built and a numerical simulation of acid rain formation has been carried out by finite element method. The model is based on diffusion of chemical species in a rain drop, pollutant mass trasfer between the air and a drop, dissociation of sulfur dioxide and oxidation of bisulfite ion by hydrogen peroxide. The simulation has proved that the concurrent washout of 50ppb sulfur dioxide and 0.1ppb hydrogen peroxide during 500m falling can acidify 0.1cm-diameter rain drop from pH5.6 to pH4.5 and that the oxidation effect of the atmospheric H2O2 (g) is not so important in the early stage of acid rain formation.
