Impact of ventilation efficiency on restraining hazardous toilet plume post-flushing in indoor environments

Abstract

This study analyzed the hybrid ventilation efficiency of indoor toilet plumes generated post-flushing with various designs. Single-sided natural ventilation and hybrid ventilation were numerically investigated to determine the impact of vent locations commonly found in multistorey buildings. An in-situ experiment was performed to identify the size distribution of the plume with time series. A computational fluid dynamics model based on the Reynolds-averaged naiver-Stokes equations and baseline k-ω turbulence equations was used to predict aerosol pollutant transmission. The aerosol-laden particles receded gradually impacted by the convection of the ambient source. Besides flush volume, temperature and ventilation scenarios were also related to the generation and droplet transmission. The results indicated that the ventilation rates were generally increased with decreased residence time if the turbulence was not suppressed. This study suggested that appropriate ventilation design could significantly reduce the average particle residence time, in which case it could also reduce the rate of virus infection.