Drying is the process of removing volatile matter, mostly moisture, from wet solid materials. The removal of the volatile substance is a consequence of heat and mass transfer between the drying medium, most often air, and the surface of the wet solid. Organic sludges have a complex porous structure, which in our case, was modeled as a liquid domain. The energy transfer between the drying medium and the surface of the solid was simplified by taking into account the thermal equilibrium between the drying medium and the solid. The temperature gradient developed through the modeled sludge is the result of a set energy sink. The drying process is then simulated using computer fluid dynamics (RDT) methods. The parameters of the drying air are of great importance for the implementation of numerical simulations. The parameters of the drying air represent the boundary conditions of the chambers fluid domain. The boundary conditions set at the inlets and outlets of the chamber, together with our model of the sludges porous zone were of crucial importance with regards to the accuracy of our model. For the purpose of determining the appropriate boundary conditions, the obtained experimental results were used. The main goal of this master thesis was the development of a model of a porous structure that will match the experimental results as accurately as possible.
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