Numerical modeling of an evaporative spray in a riser

A numerical model is developed for modeling the evaporative spray in a hot gas–solid flow. Phenomenological sub-models for the interaction between the cold evaporative spray droplets and hot particles, including momentum exchange, heat and mass transfer, are proposed based on previous experimental and numerical studies in the literature. Simulation of an evaporative water spray through a hollow cone spray nozzle in a riser operated at an elevated temperature is conducted. Comparison with available experimental measurements in terms of the spray expansion and spray width is performed, and reasonable agreement is obtained. The effect of various parameters introduced into the model is investigated in parametric studies, and appropriate values for those parameters are suggested. In addition, influences of various operating conditions including droplet size, bed temperature, and spray angle are evaluated.