CFD Assessment of COVID-19 Infection Risk in Naturally Ventilated Detached Houses

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Chalermwat Tantasavasdi
Thawanrat Rianngon
Natthaumporn Inprom


The airborne nature of COVID-19 dispersion has considerably impacted architectural and ventilation system designs. This research studies the COVID-19 infection risk in typical naturally ventilated detached houses in Thailand. Influencing parameters include the opening size and location of the infected person. Computational Fluid Dynamic was used to simulate the virus spreading in major spaces including the master bedroom, a bedroom and the living room. The Wells-Riley equation was adopted to assess personal infection risk (Pp) and area infection risk (Pa) in 12 case setups. The results reveal that opening size affects more on Pa than Pp. Increasing the opening-to-floor ratio in the range of 0.03 to 0.28 will reduce the Pa and Pp ratios in the range of 0.03 to 0.13 and 0.01 to 0.12, respectively. The location of the source, however, impacts more on Pp than Pa ratios. It varies the trend of the infection risk in the range as high as 0.69 to 0.70 according to other factors including the location of other occupants and the outlet openings.

Article Details

How to Cite
Tantasavasdi, C., Rianngon, T., & Inprom, N. (2024). CFD Assessment of COVID-19 Infection Risk in Naturally Ventilated Detached Houses. Nakhara : Journal of Environmental Design and Planning, 23(2), Article 408.
Research Articles


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