Spray drying process for powder production is widely commercialized in diary industrial sector. In this paper, a multiscale study of spray drying process with skim milk served as drying product is presented. Firstly, a characteristic drying curve model is developed to describe the heat and mass transfer of single droplet drying process. The parameters of the characteristic drying curve model are established based on the experimental observation. Then, the single droplet drying characters are incorporated into a computational fluid dynamic (CFD) solver to customize the heat, mass and momentum transfer between the droplet/particle and the drying agent flow inside a spray dryer. The CFD simulation results are validated by comparing against the experimental data observed on a pilot-scale spray dryer. A good agreement between numerical and experimental result on both of fluid phase and particle properties indicates the predictability of the CFD simulation. The influence of the drying conditions on the drying efficiency of the tower is also explored in detail.
