A numerical investigation on indoor air ventilation design and aerosol transportation: a case study in a hospital hall

The transportation of indoor aerosol particles is closely related to the infection risk of various viruses. When the pandemic of COVID-19 is anticipated to coexist with human beings in the future, the design of airflow distribution in public buildings becomes more vital not only for thermal comfort but also for epidemic prevention through controlling indoor aerosol transportation. In this paper, the conditioning of indoor air in a hospital hall (Chongzhou Traditional Chinese Medicine Hospital in Chengdu, China) is case studied by numerically simulating the indoor thermal comfort and the aerosol transportation process analysis. Simulation results indicate that thermal comfort can be first achieved by appropriate air supply forms in summer. Under the combined operation of the nozzles, square diffusers, and the breathing plane, with an average velocity of 0.26 m/s, the average temperature, and the average air age are 23.43°C and 949.59 s, respectively. Second, the arrangement of air-exhaust outlets in this hospital hall is also redesigned and simulated with three new schemes of outlets design, of which the floor exhaust scheme is optimal with the fastest aerosol discharge speed (thus the strongest pollutant discharge capacity), i.e., 62% of aerosol particles discharged in 30 s and 99% of particles discharged in 150 s. This study makes a successful attempt to optimize indoor air ventilation for preventing airborne transmission of viruses, e.g., COVID-19, offering a feasible scheme for the air distribution design in densely populated areas such as hospital halls.