Session: 7.4.2 - Fluid-Solid Flows II

Paper Number: 157875

157875 - Numerical Analysis of Respiratory Droplet Dispersion in Ventilated Spaces: Impacts of Ventilation Rates and Physical Barriers on Airborne Transmission 

Abstract: 

The COVID-19 pandemic has shown the crucial role of airborne respiratory droplets in the transmission of respiratory viruses, increasing interest in understanding aerosol dispersion dynamics in indoor environments. This study investigated the transport and dispersion of respiratory droplets in a ventilated office space featuring two mannequins separated by a partition, simulating a scenario where one mannequin emits droplets while speaking. The Transition k-kl-ω turbulence model was utilized to simulate airflow patterns, while the Lagrangian particle tracking method coupled with the Discrete Random Walk (DRW) model evaluated droplet trajectory dispersion.

The simulations were conducted using the ANSYS-Fluent code. We examined the effects of varying ventilation rates (Air Changes per Hour, ACH) and droplet sizes on the distribution and concentration of particles near the receptor mannequin. Results revealed that higher ACH rates significantly reduced the concentration of smaller droplets in the breathing zone, whereas larger droplets settled more rapidly due to gravitational forces. The partition between the two mannequins was shown to influence airflow patterns, altering the spatial distribution of particles. The droplet concentrations were evaluated using a two-way coupling approach in ANSYS-Fluent code and further validated against earlier diffusion models using MATLAB.

These findings underscored the nonuniform distribution of respiratory droplet concentration in the room and highlighted the impact of ventilation strategies and physical barriers in mitigating exposure to airborne droplets. The outcomes of the study provided insights for improving indoor air quality and reducing the risk of airborne transmission of respiratory diseases, including COVID-19 and influenza.

Presenting Author: Amirmasoud Anvari Clarkson University

Presenting Author Biography: