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Turbulent dispersion via fan-generated flows.
Siobhan K Halloran1, Anthony S Wexler2, William D Ristenpart1
1Department of Chemical Engineering and Materials Science, University of California Davis, Davis, California 95616, USA.
Physics of Fluids (Woodbury, N.Y. : 1994)
|June 17, 2014
Summary
Turbulent dispersion in fan-generated airflow shows a plume width invariant to fan speed. This finding simplifies modeling of disease and pollution spread indoors.
Area of Science:
- Fluid dynamics
- Environmental science
- Aerosol science
Background:
- Turbulent dispersion is well-studied in controlled wind tunnels.
- Unconditioned flows from fans in indoor environments are less understood.
- These flows are critical for pathogen and contaminant transport.
Purpose of the Study:
- Investigate turbulent dispersion of passive scalars in fan-generated airflow.
- Determine the effect of fan speed on plume characteristics.
- Simplify models for indoor contaminant transport.
Main Methods:
- Experimental study using an axial fan to generate airflow.
- Release of a point source of passive scalars.
- Analysis of plume width and its relationship to fan speed.
Main Results:
- Plume width was found to be invariant with respect to fan speed.
- This suggests a consistent dispersion pattern regardless of fan intensity.
- Highlights the unique nature of unconditioned turbulent flows.
Conclusions:
- Fan-generated airflow exhibits predictable dispersion patterns.
- A simplified modeling approach for indoor pollutant and pathogen spread is proposed.
- Findings are relevant for public health and environmental management in indoor spaces.
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