第十一届全国室内环境与健康大会

7 / 2023-03-30 16:32:03

Transmission of droplet aerosols in an elevator cabin: Effect of ventilation mode

Droplet dispersion, Elevator cabin, Air curtain, COVID-19, Numerical modelling

The recent outbreak of COVID-19 has threatened public health. Due to relatively sealed environment and poor ventilation, passengers in elevator cabins are faced with a risk of respiratory tract infection. The distribution and dispersion of droplet aerosols in the elevator cabin remain unclear. This study investigated transmission of droplet aerosols exhaled by the source patient under three ventilation modes. The droplet aerosols produced by nose breathing and mouth coughing were resolved by CFD simulations. We adopted the RNG k-ε turbulence model to simulate flow field and the Lagrangian method to track droplet aerosols. In addition, the influence of ventilation mode on the droplet transmission was evaluated. The results showed that up to 12.86% of droplet aerosols were deposited on the susceptible individual under the current mixed ventilation. Most of droplet aerosols were gathered in the upper contaminated zone of the cabin under the displacement ventilation with the maximum inhalation proportion of 0.071%. Air curtain confined the transmission of droplet aerosols with the minimum ratios of inhalation, deposition and suspension and was suggested to utilize to reduce the exposure risk.