Effect of different mechanical fans on virus particle transport: A review
Document Type
Article
Publication Date
2-1-2025
Abstract
In recent years, repeated outbreaks of airborne viruses have normalized human coexistence with these viruses. The complex turbulence and vortices generated by different fan types and operation modes affect virus removal effectiveness. This paper reviews the potential impact and actual effectiveness of different fans in mitigating indoor virus transmission, highlighting their advantages and limitations. Downward rotating ceiling fans can rapidly dilute virus concentration (21-87%) in the breathing zone due to jet cores, with efficiency depending on rotational speed and particle diameter. However, the reprocessing problems of large particles being deposited on surfaces, and small particles settling and rebounding into the air remain unresolved. Upward-rotating ceiling fans do not contribute to indoor virus removal. Exhaust fans generate a negative-pressure environment, which helps expel viruses quickly. But improper vortex zones can increase virus retention time 16-40 times. Air-apply fans effectively dilute and transport viruses only when delivering airflow exceeding 0.5 m/s directly into the breathing zone. Additionally, combined fan strategies remain underexplored, despite potential benefits. This review underscores the need for standardized definitions of particle removal effectiveness and calls for further research on how climatic conditions and thermal comfort influence fan-based interventions.
Keywords
Airborne transmission, Airflow patterns, Ceiling fan, Exhaust fan, Air-apply fan
Divisions
BuiltEnvironment
Funders
National Natural Science Foundation of China (NSFC),International Science and Technology Cooperation Center in Hebei Province [Grant No: 20594501D; 51578011]
Publication Title
Buildings
Volume
15
Issue
3
Publisher
MDPI
Publisher Location
MDPI AG, Grosspeteranlage 5, CH-4052 BASEL, SWITZERLAND