[RobV]

Hello,

for a project, I will be running simulations (in ANSYS Fluent) to determine particulate matter concentrations in an urban environment. The size range that I am looking into is everything below 10 micrometer (PM10).

However since these particles become relatively small, I don't know if i have to model the exact paths of the particles. It might be possible to define the pollution as a species. This will significantly decrease the computational costs since the mesh that i'm using consists of 100,000,000 cells.

Does anyone know from what size ranges PM can be modelled as a gas instead of real particles. I cannot find much on this topic in literature, so I hope anyone is familiar with this topic.

Kind regards,
Rob