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-A numerical study for the modelling of porous particles packed bed drying in one and two dimensions (1D and 2D) is presented in this work. This model is based on the averaging volume approach using two scale changes. Taking into account the non validity of the thermal equilibrium between the gas phase and the porous particle, a two temperatures model is then developed. The numerical resolution of macroscopic equations describing heat and mass transfer during the drying of a packed bed is carried out by the method of finite volume. Experimental data for spherical porous alumina particles reported in the literature were used for the validation of the model. A good agreement was found. The influence of particles thermophysical properties and operating variables is tested. A set of time-space evolution describes the progression of these variables with time, in the height and radius of the packed bed. The model results allow a better understanding of the heat and mass transfer mechanisms involved in a packed bed drying process.

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-This study aimed to numerically investigate the air flow and contaminant dispersion in a ventilated room. The URANS equations supplemented with energy and concentration equations are solved using the scStream code. We are targeting primarily the ventilation effectiveness (εc) and the index of indoor air quality (IIAQ). Different displacement and mixing ventilation modes are investigated in isothermal conditions. The ventilation flow rate is 50 m 3 .h −1 Here, our ultimate aim is to suggest an effective ventilation that can ensure a good indoor air quality. The RN G k − ε model was adopted to handle the turbulence. CFD simulations were systematically checked, whenever possible, through available results. The simulation results indicate that the ventilation effectiveness to remove a contaminant and the index of indoor air quality are substantially influenced by the ventilation mode and the location of inlet and outlet air. From this study, it appears that the air flow and contaminant dispersion in a ventilated room can be typically predicted or evaluated by computer simulations.