Numerical and Experimental Investigation into Heat Transfer Process in a Fluidized Bed of Alumina Powder

In this study, the process of heat transfer in a fluidized bed of particles belonging to group A of Geldart classification was investigated. For this, an experimental setup was installed, in which a bubble fluidity regime was formed with the combination of hot air and alumina powder belonging to group A of Geldart classification. In each experiment, the temperature of solid phase and outlet gas were measured and recorded over the time, by keeping temperature constant at the inlet opening. Due to the low humidity level of solid particles, mass transfer between the phases was ignored. In the following, using three phase modeling equations and experimental data, a correlation has been provided for predicting heat transfer coefficient between the solid and interstitial gas phases. In this study, heat capacity of alumina powder has been considered as a function of temperature. In addition, finite volume method has been used for solving three-phase model equations. The results of this study show very good conformity between experimental data and numerical simulation so that the maximum error of numerical modeling with experimental data is 9% and the highest temperature variation in the bed happens early in 2 minutes of the process that demonstrates the high rate of heat transfer is in this type of beds.