The Effect of Turbulence on the Spreading of Infectious Airborne Droplets in Hospitals
The dispersion of droplets plays an important role in the transmission of disease in a hospital environment. The challenge is that as they move, their properties change due to evaporation, the Wells (Am. J. Hyg. 20:611–618, 1934) droplet-nuclei hypothesis. In this paper we examine the effect of evaporation on their movement within a homogeneous turbulent environment. The effect of turbulence is to significantly increase the transmission distance and spread. These numerical results demonstrate that by reducing the level of turbulence, the potential for spreading diseases is reduced. This is in accordance with available experimental/in situ measurements.
KeywordsSevere Acute Respiratory Syndrome Droplet Diameter Severe Acute Respiratory Syndrome Homogeneous Turbulence Fall Velocity
C.A.K. acknowledges support from the EPSRC. EPSRC (EP/G009007/1) supported a one day meeting on ‘Airborne Transmission in Hospitals’ where this work was presented.
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