JAUE2020-071: The ventilation effect on COVID-19 prevention in office buildings

Abstract

This research aims to utilize the ventilation to dilute the virus concentration and provide operational guidance for COVID-19 prevention in office buildings. Taking a typical large-space office area in Shanghai as the research object, this paper adopted a research method combining numerical simulation with field measurement to investigate the natural ventilation effect on the transmission risk of COVID-19 during the transition season. In the stage of numerical simulation, the air age distribution of the height of personnel's respiratory zone was obtained by CFD simulation and four characteristic points with different ventilation efficiency were selected for setting up CO2 sensors in the next actual measurement stage. By monitoring the indoor CO2 concentration which is widely used as an indoor environmental control indicator, the dilution effect of natural ventilation on indoor aerosols was analysed. The results show that under the same personnel density, the higher the air age, the higher the indoor CO2 concentration; when the CO2 concentration exceeds the warning value, it is necessary to increase the fresh air volume to reduce the virus concentration. In view of the lack of fresh air, this research proposed optimization schemes of natural ventilation assisted by mechanical ventilation to improve buildings’ ventilating ability.