CFD-aided population balance modeling of a spray drying process

Due to the widespread application of spray dryers, the model-based optimization and control of the process are of great interest. Therefore, a reduced order model based on a population balance approach for the spray drying process is developed to accurately capture the shrinkage and drying mechanisms. The population balances describe the two-dimensional distribution of the moisture content and the granule size. The model is validated by experiments in a pilot scale spray dryer. Information from CFD simulations and previous single droplet experiments are used to determine suitable model parameters. The results show a good agreement of the model with experimental findings and promote the suitability of the population balance approach. Furthermore, a novel method of extracting information on the trajectories from detailed CFD simulations and inserting them into the reduced order model is presented. This increases the accuracy of the model without changing the computational complexity.