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The aim of this work concerns the study of the hydrodynamic of a air-urea fluidized bed for uniformparticle size. The study involves experimental measurements in a urea pilot scale fluidized bed and CFDsimulations conducted in the frame of the ANSYS 12.1 CFD software. This contribution is the first stageto make possible the CFD simulation of the entire urea melt granulation fluidized bed.The experiments were carried out in a conical pilot-scale unit. To this end, a bubbling air-urea fluidizedbed filled with urea granules of a mean diameter of 2.6 mm (Geldart D group) was used. The superficialair velocities ranged between 0 and 3 m/s.A multifluid Eulerian approach for granular flow, with the fluid and solid phases treated asinterpenetrating continuum phases, was selected for the fluidized bed simulation. The 2D computationaldomain was discretized in rectangular cells and the corresponding mesh validation was done in order toguarantee mesh independence results. The CFD model uses empirical drag laws to calculate themomentum exchange between the fluid and the solid phases. Several drag laws are available and theirinfluence on hydrodynamic parameters was explored in this work. The drag models used were:Symlal_O´Brien, Gidaspow, Wen-Yu, Symlal_O´Brien (with customized parameters), Richardson-Zaki,Representative- Unit-Cell (RUC) and Hill-Koch-Ladd.The fluid dynamic parameter investigated were the pressure drop, the minimum fluidization velocity andthe bed expansion. The numerical results show that the code ANSYS-Fluent is capable of predicting thegas-solid behavior of a urea bubbling fluidized bed at the explored operating conditions. Concerning thedrag law model, this study shows that O?Brien´s law is the most appropriate approach to be used for thesimulations dealt with here.