Eulerian-Lagrangian modelling of bio-aerosols irradiated by UV-C light in relation to SARS-CoV-2 transmission.

It is well known that several viruses, as well as SARS-CoV-2, can be transmitted through airborne diffusion of saliva micro-droplets. For this reason many reserach groups have been devoted their efforts in order to gain new insight into the transport of fluids and particles originted from human respiratory tracts. This paper aims to provide a contribution to the numerical modelling of bio-aerosols. In particular, the well-known problem around the safety distance to be held for avoiding virus transmission in the absence of external wind is further investigated. Thus, new indexes capable of evaluating the contamination risk are introduced and the possibility to inactivate virus particles by means of an external UV-C radiation source is studied. For this purpose, a new model which takes into account biological inactivation deriving from UV-C exposure in a Eulerian-Lagrangian framework is presented.