The theoretical prediction and simulation of radioactive aerosol diffusion based on the revised Gaussian plume model

摘要

A radioactive aerosol diffusion Gaussian plume model is revised in the vicinity of nuclear power plant considering effects of the emission heights,ground reflection,dry deposition,wet deposition,radioactive decay and other factors based on the open field diffusion model.Numerical simulations are performed to calculate the concentration distribution of the radioactive aerosol and to determine the evacuation zone.Simulation results show that the atmospheric stability tends to be the key factor of the radioactive aerosol distribution and the major diffusion zone prove to be in the downwind direction.With atmospheric stability degrees ranging from A to F,the area of the evacuation zone increases,whose maximum span in downwind direction expand to 28 km compared with the 0.8 km in crosswind direction.