A continuum particle–wall heat transfer model for polydisperse fluidized beds

Abstract A continuum particle–wall heat transfer model is essential for continuum simulations of gas–solid fluidized beds, yet models applicable to polydisperse systems remain lacking. In this study, a modified version of the Rong and Horio discrete element method (DEM) particle–fluid–particle/wall heat transfer model was proposed by incorporating particle thermal conductivity. The modified DEM model accurately predicts the effective thermal conductivity in an experimental packed bed. Based on computational fluid dynamics–discrete element method data, a continuum particle–wall heat transfer model was developed for monodisperse systems and successfully extended to polydisperse systems by introducing a volume‐averaged particle size. Additionally, a theoretical expression was established to predict the contribution of each particle component to the overall heat transfer coefficient in polydisperse beds. The model predictions agree well with simulation results, especially at relatively low fines contents (<15%). This work provides a reliable particle–wall heat transfer model for continuum simulations of polydisperse fluidized beds.