Impact of Ventilation Speed on Co2 Concentration and Virus Aerosol Dispersion: A Cfd Study

Abstract

Indoor air quality (IAQ) is a critical factor influencing human health and comfort, especially in confined office environments. Inadequate ventilation can lead to the accumulation of pollutants such as CO2 and viral aerosols, which pose significant health risks. This study investigates the dispersion characteristics of CO2 and virus-laden aerosols under different ventilation speeds (0.7 m/s, 1.4 m/s, 2.1 m/s) and assesses the reliability of air age as an indicator of pollutant buildup. A 3D CFD model was developed to simulate the spatial distribution of these airborne contaminants, with results validated through experimental data collected from key measurement points within an office setting. The findings highlight distinct differences between gaseous pollutants and particulate pollutants. CO2, due to its high diffusivity, exhibits relatively uniform dispersion, while viral aerosols show considerable heterogeneity in their distribution. Overall, relying solely on CO2 monitoring is insufficient. A more comprehensive set of indicators, including airflow patterns and aerosol behavior, is crucial for designing effective ventilation strategies. This study provides a validated framework for improving indoor ventilation systems, reducing airborne infection risks, and enhancing IAQ in confined environments. It emphasizes the importance of multi-faceted indicators in IAQ assessments, advocating for a combined analysis of gas-phase pollutants, particle size distribution, and localized airflow patterns.

Keywords: Indoor Air Quality (IAQ), pollutants, CO2 Distribution, ventilation strategies, Air Age, Pollutant Dispersion