Investigation of heat transfer in bubbling fluidization with an immersed tube

Fluidized beds with immersed tubes are widely used in many applications involving exothermic/endothermic reactions. Temperature control is an important concern in these applications, and has been studied extensively in literature by experiments at a macroscopic level. However, it is difficult to obtain microscopic information from those studies which is important to develop understanding of heat transfer mechanisms in this system. In this work, a coupled discrete particle simulation (DPS) and computational fluid dynamics (CFD) method is used to study heat transfer in fluidized beds with immersed tube. The results show that the predicted distribution and magnitude of average local heat transfer coefficients (HTC) agree well with experimental measurements. The related mechanisms are analyzed through particle flow pattern, porosity distribution and contact number. The results are useful for temperature control and prediction of tube erosion in fluidized beds.