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Information related to spray impingement onto tablets, coating film drying and water absorption in tablet cores under pharmaceutical coating process conditions is limited. In this work, we therefore investigate the fundamental phenomena that are taking place at the point of contact between the tablet and the coating in an effort to reduce the number of defective tablets, to maximize tablet shelf-life and to enable a more accurate selection of the optimal process conditions. Recent models, which simulate coating behavior on tablets, have been mainly focused on single droplet impact cases. On the contrary, the current model is able to predict film formation on tablets during spray impingement while accounting for spray droplet-film interactions. Thus, the model developed in this work provides useful insight into coating spreading efficiency that can indicate defect formation. Main outputs of this work include predictions of the amount of water and polymer that penetrate into the porous tablet core and the percentage of water that evaporates from within the tablet. Knowledge of the amount of water and polymer in the tablet core can be used to optimize the shelf-life of the tablet and control the adhesion of the dry coating film. The current model assumptions, which are solely based on physics and are specific to the tablet coating process, allow one to solve coating flow problems much faster than equivalent models in commercial CFD software. The mathematical model is implemented in gPROMS employing the Modelbuilder modeling platform and it is validated against experimental data taken from the literature.