Granular Matter (2018) 20:56 https://doi.org/10.1007/s10035-018-0813-2 ORIGINAL PAPER Numerical analysis of restitution coefficient, rotational speed and particle size effects on the hydrodynamics of particles in a rotating drum Afshin Taghizadeh 1 · Seyed Hassan Hashemabadi 1 · Esmaeil Yazdani 1 · Soheil Akbari 1 Received: 29 December 2017 © Springer-Verlag GmbH Germany, part of Springer Nature 2018 Abstract Hydrodynamic behavior of two dimensional horizontal rotating drum was studied by using finite volume method and granular kinetic theory. In this work, the effects of the different parameters such as rotation speed, restitution coefficient and particle size on the hydrodynamic and especially on the granular temperature of particles were investigated. At first, the results of present work were verified with previous experimental results. Packing limit of 0.6 and restitution coefficient of 0.95 with Gidaspow inter-phase momentum coefficient showed the good agreement with experimental works. It is found that by increasing the restitution coefficient, the granular temperature at different depth of bed increased and affected the hydrodynamic behavior of the bed. Also, particle size and rotation speed directly changed the granular temperature. Moreover, augmentation of the rotation speed leads to increasing the repose angle which caused better mixing of bed, granular temperature rising and consequently particle velocity alteration in the bed. Keywords Rotary bed · Granular temperature · Restitution coefficient · Computational fluid dynamics (CFD) · Particulate flow List of symbols C D Drag coefficient d Diameter (m) e ss Restitution coefficient g Gravity acceleration (m/s 2 ) g 0ss Radial distribution function k θ s Energy diffusion coefficient p Pressure (Pascal) p s Solid pressure (Pascal) Re Reynolds dimensionless number t Time  v Velocity (m/s) Greek symbols β Drag coefficient between gas and solid phase γ s Dissipation of the turbulent kinetic energy B Seyed Hassan Hashemabadi hashemabadi@iust.ac.ir 1 Computational Fluid Dynamics (CFD) Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology (IUST), Tehran 16846-13114, Iran ε Volume fraction Θ Granular temperature λ Bulk viscosity μ Dynamic viscosity (kg/m s) ρ Density of gas phase (kg/m 3 ) ¯ ¯ τ Viscous stress tensor (Pascal) ϕ s Energy exchange between the gas and the solid phases ω Rotation speed (rpm) Subscripts col Collisional f Fluid fr Friction g Gas kin Kinetic max Maximum p Particle s Solid 0123456789().: V,-vol 123