Hinds1999-characteristic-of-particles

Real particles are not spherical in form, but have different shapes. That is why the aerodynamic particle diameter is introduced for simulations. The aerodynamic diameter used in the simulations, dp, is the diameter of the unit density ( ρp = 1 g/cm3) sphere that has the same settling velocity as the particle. Particles can appear as human hair, parts of human skin and parts of different building or other materials (Hinds, 1999).