COVID-19: Plastic Cover Effect in Banks

Plastic Cover Effect in Banks Regarding COVID-19, ANSYS Fluent Simulation

Description

This project simulates the release of virus particles from a patient's mouth within a bank setting, using ANSYS Fluent. The geometry represents a bank interior containing a table, two chairs, and two people — one of whom is defined as infected, serving as the virus source through coughing, with the mouth treated as the reference surface for discrete virus particle release.

Two configurations were modeled: one with no barrier present, and a second incorporating a thin plastic cover positioned between the two people across the table. The domain was meshed in ANSYS Meshing, totaling 1,570,219 elements for the no-cover case and 1,618,366 elements for the case with the plastic cover. Given the particle/virus dispersion nature of the problem, a transient solver was used throughout.

Methodology

This study investigates coronavirus transmission from a bank customer to a healthy employee, comparing scenarios with and without a plastic barrier positioned between them to evaluate its effectiveness at blocking virus particle transmission.

The Discrete Phase Model (DPM) tracked virus-laden particles individually within the continuous cabin airflow. Several physical sub-models were applied: two-way turbulence coupling, stochastic collision, coalescence, and breakup, with unsteady particle tracking using a time step of 0.001 s. Particles were injected as water droplets from the surface of the infected patient's mouth, representing the physical expulsion of virus-laden droplets during a cough, defined at 310 K, 32 m/s, and a flow rate of 0.018 kg/s, released over an interval of 0 to 0.1 seconds. Since droplet size varies during propagation, a Rosin-Rammler logarithmic distribution was used to represent the resulting range of particle diameters.

This droplet-based approach required activating the Species Transport model alongside DPM, tracking three gas species throughout the domain — oxygen (O₂), nitrogen (N₂), and water vapor (H₂O) — with turbulence resolved using the RNG k-epsilon model and the energy equation enabled to capture temperature distribution throughout the space.

Conclusion

Results include particle tracking of the virus particles across multiple time intervals, based on each particle's residence time and diameter, compared directly between the with-cover and without-cover configurations. The results clearly demonstrate the plastic cover's effectiveness at blocking coronavirus particle dispersion — confirming that the modeled barrier meaningfully reduces virus transmission risk between the customer and bank employee compared to the uncovered scenario.