CFD Simulation of Particle Diffusion at the Region near the Entrance or Exit of An Underground Parking Lot

Nanoparticles have been demonstrated to have severely adverse impact on human health. As underground parking lot is a typical enclosed space with huge amount of vehicle-related particles, particle diffusion and pollution should be of great importance. The study employed a three-dimensional numerical model to simulate particle concentration distribution under transient natural wind through the entrance of the underground parking lot. The simulation results demonstrated that particle diffusion was controlled by natural wind through the entrance when vehicle stopped exhaust. Natural wind is an effective way to dilute nanoparticles exhausted by vehicles and contributed to a more uniform distribution of nanoparticles near the entrance in the parking lot. The results could provide fundamentals for the future application of ventilation design, and can be used to assess human exposure to vehicle particle pollutants at underground parking facilities.