Numerical Study on the Effect of Driving Distance on the Diffusion of PM2.5 in the Street

摘要

The influence of inter-vehicle distance on the diffusion process of PM2.5 in the underlay surface of urban streets is studied. Firstly, the diffusion process of tracer gas PM2.5 is simulated using CFD, and the emission factors of PM2.5 under different vehicle types and speeds is analyzed and summarized. Then, using the improved MIRA vehicle model, a PM2.5 diffusion model of the traveling vehicle at different intervals was established. In the end, POST post-processing was applied to the model, and the PM2.5 concentration field cloud map and the velocity field cloud map around the vehicle body were compared and analyzed to obtain the diffusion rule of PM2.5 emission from the vehicle exhaust gas.