Numerical Simulation of Asphalt Fumes Diffusion during Pavement Construction Using CFD Method

A massive amount of harmful asphalt fumes is emitted from the Hot Mix Asphalt (HMA) during asphalt pavement construction. The traditional measurement of asphalt fumes concentration is mostly based on onsite sampling and laboratory experiments. This study proposes asphalt paving model based on computational fluid dynamics (CFD) to investigate the diffusion of asphalt fumes. A three-dimensional physical model of asphalt fumes diffusion was built and then controlled by the technology of dynamic mesh to analyze the process of the asphalt paving. Five monitoring points were set up in the actual construction site to validate the effectiveness of the simulation model and identify the factors affecting the diffusion. It is found that the relative error range is 3.79%–7.93%, which verifies the effectiveness of the numerical simulation results, and that the wind speed becomes the main factor, which promotes the asphalt fume diffusion. This study contributes to the improvement of pavement construction and helps make construction plans efficiently for pavement managers.