Motion and Temperature of Individual Particles in Two-Dimensional Fluidized Bed With Heat Transfer

Fluidized beds are widely used in industrial processes concerned with heat transfer such as combustion, gasification, catalytic reaction and calcination. In recent years, numerical simulation models that predict the heat transfer phenomena in fluidized bed in the framework of DEM-CFD coupling simulation are developed. The heat transfer in fluidized beds is conducted by several mechanisms and its behavior is extremely complex. In order to improve these numerical models, it is important to know the relation between the convective and diffusive motion of particles and heat transfers in the particle-level. In the present study, a measurement technique based on the coupling between particle tracking velocimetry (PTV) and infrared thermography (IT) measurements is proposed. By using the technique, the motion and the temperature of individual particles and its relations with the characteristic flow structures formed in fluidized beds can be investigated simultaneously without disturbing the flow field. After careful preparations, the technique is applied to a two-dimensional gas-fluidized bed under a spouting condition and the motion and the temperature of individual particles largely-influenced by the bubble occurrences are clearly observed. The relations between convective and diffusive behaviors of individual particles and heat transfer in the bed are studied in detail.