The numerical study was carried out using the Ansys software. The method used in this study consists of doing some simple simulations first and only then were they perfected until they became more complex, complete and closer to reality. Initially, a stationary analysis of particles expired by the nose and expelled by the mouth was performed, modeling a simple nose and mouth geometry. At a later stage, some parameters were corrected and a transient analysis was performed.

In an intermediate phase, the study of the trajectory of the particles when they are exhaled by the nose when breathing was carried out with the implementation of the respiratory cycle. 

As the analysis of the respiratory cycle has been performed, the next study is that of the trajectory when a sneeze and cough occur.