Cyclone dimensionless pressure drop, cut size, and separation slope: One dimensionless number (Reynolds) to rule them all

The flow field and performance characteristics of the high-efficiency Stairmand cyclone have been computationally investigated at a wide range of Reynolds numbers Re out = 84 − 252876 by varying the cyclone diameter, inlet velocity, operating temperature and pressure using the LES simulations. The effects of these parameters on the dimensionless cyclone performance characteristics (Euler number, square root of Stokes number and slope of the transformed grade efficiency curve) and dimensionless lip flow and lip velocity have been revealed. Five critical Reynolds numbers which correspond to the transition between different regimes and sub-regimes have been determined. All three dimensionless cyclone performance characteristics and two lip flow characteristics are ruled by the Reynolds number. • Cyclone performance have been investigated at a wide range of Reynolds numbers; • Reynolds number rules all dimensionless performance parameters of the cyclone; • Five critical Reynolds numbers have been determined; • Two different dimensionless cut-sizes, based on the Stokes number and ψ 50 , were analysed.