Characterization and modelling of a family of cyclone aerosol preseparators

Experiments have been carried out on two groups of cyclones to determine how their behaviour depends on geometry and flow rate. Empirical models predicting the cyclone cut points as a function of body diameter and flow rate were fitted to the data. Additional geometrical parameters such as the cone shape, grit pot diameter, inlet and vortex outlet dimensions were also found to influence the cyclone cut points, but not the slope of the penetration curves. The empirical models fitted were used to calculate cyclone dimensions suited to a number of different applications in health-related aerosol sampling. Cyclones were identified to sample according to the proposed EPA fine particle standard and also to international conventions for respirable and thoracic aerosol fractions. The cyclones tested were shown to have significant advantages in terms of sampling bias over other cyclones currently in use for sampling respirable dust.