Numerical simulation of the effect of visitor's movement on bacteria-carrying particles distribution in hospital isolation room

The aim of this paper is to simulate numerically the air flow induced by a walking visitor and its eff ects on the contaminant transport and ventilation system e ffectiveness. To this end, the following models will be used in this study: the Lagrangian Discrete Random Walk (DRW) model to trace the motion of BCPs, the dynamic mesh method to simulate the visitor movement, and the Reynolds Averaged Navier-Stokes (RANS) model to solve the air flow. The validation results of the numerical method are in full agreement with the available experimental data in the literature. The fi ndings of the present study indicate that the visitor's movement has remarkable e ect on the basic  air flow, and the increase of the visitor moving speed can decrease the risk of infection in the AIIR. It is also found that the concentration of BCPs in the back of visitor exceeds10 cfu/m3, and the small distance between the patient and visitor has a negative impact on increasing the BCPs infection of the patient in AIIR. At the same time, it is observed that the effect of walking speed on the ventilation  e ffectiveness index is not remarkable.

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