Abstract: This paper presents the prediction of air flow, temperature patterns and mass fraction of water vapour in a co current pilot plant spray dryer fitted with pressure swirl nozzle using 3 dimensional model. The modeling was done with CFD package star ccm+ 9.04, in which the droplet/particle phase is modeled with Langrangian approach and hot air stream is modeled with Euler approach, K-? model is used to analysis the turbulence swirl in the spray dryer. Good results were obtained with the modified balanced double tangential air inlets spray dryer when compared with the conventional single tangential air inlet spray dryer . the problem of stick of the wet particles on the walls of the spray dryer and cone part of the spray dryer was eliminated in the modified model. A higher uniformity of temperature and air mass fraction on the horizontal planes of the spray dryer were obtained by the modified design of the spray dryer. This work was carried with multiphase flow and the feed considered for the work is silica slurry (40% Si, 60%liquid water) for the analysis.In this work the effects of the air flow pattern on the droplets trajectory, residence time, distribution of droplets, and the deposition of droplets on the wall were compared with the conventional model and the modified air inlet design model.
Keywords: Spray drying; Wall deposition; turbulence; Computational fluid dynamics (CFD)