Simulation of massloading effects in gas solid （模拟massloading效应气体固体）.pdfVIP

Powder Technology 163 (2006) 59 – 68 /locate/powtec Simulation of mass-loading effects in gas–solid cyclone separators J.J. Derksen a,⁎, S. Sundaresan b , H.E.A. van den Akker a a Kramers Laboratorium voor Fysische Technologie, Delft University of Technology, Prins Bernhardlaan 6, 2628 BW Delft, The Netherlands b Department of Chemical Engineering, Princeton University, Princeton, NJ 08544, USA Available online 10 March 2006 Abstract Three-dimensional, time-dependent Eulerian–Lagrangian simulations of the turbulent gas–solid flow in a cyclone separator have been performed. The Eulerian description of the gas flow is based on lattice-Boltzmann discretization of the filtered Navier–Stokes equations, where the Smagorinsky subgrid-scale model has been used to represent the effect of the filtered scales. Through this large-eddy representation of the gas flow, solid particles with different sizes are tracked. By viewing the individual particles (of which there are some 107 inside the cyclone at any moment in time) as clusters of particles (parcels), we study the effect of particle-to-gas coupling on the gas flow and particle behavior at appreciable mass-loading (0.05 and 0.1). The presence of solid particles causes the cyclone to lose some swirl intensity. Furthermore, the turbulence of the gas flow gets strongly damped. These two effects have significant consequences for the way the particles of different sizes get dispersed in the gas flow. It is anticipated that the collection efficiency gets affected in opposite senses: negatively by the loss-of-swirl, pos