Journal article
Comparing airborne infectious aerosol exposures in sparsely occupied large spaces utilizing large-diameter ceiling fans
Concordia University1
University of California at Berkeley2
The Air Movement and Control Association International3
Big Ass Fans4
Pennsylvania State University5
Indoor Environment, Department of Environmental and Resource Engineering, Technical University of Denmark6
Department of Environmental and Resource Engineering, Technical University of Denmark7
Well Living Lab8
In sparsely occupied large industrial and commercial buildings, large-diameter ceiling fans (LDCFs) are commonly utilized for comfort cooling and destratification; however, a limited number of studies were conducted to guide the operation of these devices during the COVID-19 pandemic. This study conducted 223 parametrical computational-fluid-dynamics (CFD) simulations of LDCFs in the U.S.
Department of Energy warehouse reference building to compare the impacts of fan operations, index-person, and worker-packing-line locations on airborne exposures to infectious aerosols under both summer and winter conditions. The steady-state airflow fields were modeled while transient exposures to particles of varying sizes (0.5–10 μm) were evaluated over an eight-hour period.
Both the airflow and aerosol models were validated by measurement data from the literature. It was found that it is preferable to create a breeze from LDCFs for increased airborne dilution into a sparsely occupied large warehouse, which is more similar to an outdoor scenario than a typical indoor scenario.
Operation of fans at the highest feasible speed while maintaining thermal-comfort requirements consistently outperformed the other options in terms of airborne exposures. There is no substantial evidence that fan reversal is beneficial in the current large space of interest. Reversal flow direction to create upward flows at higher fan speeds generally reduced performance compared with downward flows, as there was less airflow through the fan blades at the same rotational speed.
Reversing flow at lower fan speeds decreased airflow speeds and dilution in the space and, thus, increased whole-warehouse concentrations.
Language: | English |
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Year: | 2023 |
Pages: | 110022 |
ISSN: | 1873684x and 03601323 |
Types: | Journal article |
DOI: | 10.1016/j.buildenv.2023.110022 |
ORCIDs: | Wargocki, Pawel , 0000-0002-0653-3612 , 0000-0001-5749-6543 , 0000-0002-8124-0772 and 0000-0003-3807-2002 |
Airborne CFD COVID-19 Ceiling fan Drift-flux SARS-CoV-2 Warehouse