Influence of baffles on mixing and heat transfer characteristics in an internally heated rotating drum

Baffles can effectively improve the mixing and heat transfer in internally heated rotating drums. To explore the performance of baffles, discrete element method (DEM) is employed in this work, and the influence of the placement and length of baffles on the mixing and heat transfer in an internally heated drum is investigated. The simulation results show that a central cross baffle promotes the mixing and heat transfer significantly, and the optimal length varies with material properties, for example, at the length-to-diameter ratio L/D = 0.4 for monodispersed glass particles, 0.6–0.7 for binary glass-steel mixtures. The peripheral baffle generally weakens the mixing and heat transfer performance, and effects only for a sufficiently long peripheral baffle at the length-to-radius ratio L/R = 0.9. Baffles promote the heat transfer process and do not change the thermal contribution of heat transfer paths. [Display omitted] •Effect of baffles on mixing and heat transfer in drums is studied by DEM.•The optimal length-to-diameter ratio of central baffles varies in a range of 0.4–0.7.•The traditional short peripheral baffle slightly deteriorates mixing and heat transfer.•The peripheral baffles perform best at high length-to-radius ratio of 0.9.•Baffles do not change the thermal contribution of heat transfer paths.