The objective of this study is to describe moisture distribution in a rotating porous cylinder. Variable orientation of the gravitational and centrifugal forces during rotation causes rather complex, unsteady distribution of the moisture content. The optimal speed of rotation which provides the minimum nonhomogeneity of the distribution can be found. A cell model for this purpose is proposed. The model is based on the theory of Markov chains. Transition probabilities in the chain of cells are conditioned by pure diffusion and convection caused by the forces. The basic features of the process are investigated and the optimal process parameters are found.