(406h) Three Dimensional CFD Simulation of Two-Phase Flow in Pilot Plant Dryer

Drying technology is one of the most important process in industrial applications. Generally, in this technology gas and solid phases are in contact. Depending on the process, dryer regimes may be various. CFD technique is widely used for better understanding of phenomena in different types of apparatus and various scale. For modeling of multiphase flow two approach is be considered, Eulerian-Eulerian and Eulerian-Lagrangian. In this work, applied CFD simulation for investigation of fluid flow in three-dimensional gas-solid pilot plant fluidized bed dryer. Eulerian-Eulerian model combining the kinetic theory of flow (KTGF) for solid phases was applied. KTGF based on continuum assumption and is appropriate for simulating of the large number of solid particles in large scale of fluidized bed. In this theory, some parameters defined for solid phases such as solid pressure, solid temperature, radial distribution and etc. In addition, used Syamlal-Obrien drag function for calculating of the momentum exchange coefficient. The validation is performed by comparing with the experimental results such as bed expansion. Usually, study the effects of operating parameters is very important because the flow field affected by these parameters. The operating parameters gas velocity, initial height of the bed, particle diameters, solid properties and etc. In the end, it was observed that the inlet gas velocity could be significant effects on hydrodynamics and consequently change the heat transfer rate in the dryer. Therefore, by using the validate CFD model can be predicted flow behavior and investigation of efficiency by changing of operating parameters.