Heat Transfer from Horizontal Immersed Tube in Particles Bed

Experiments have been performed to investigate heat-transfer characteristic of a heated tube immersed horizontally within particles bed. Measurements were carried out for the ranges of fixed bed to fluidized bed. A variety of particles with densities ranging from 60 to 8960kg/m3 and with thermal conductivities of 0.043 to 352 W/(m·K) were utilized as testing particles, while an air as working fluid. The maximum heat transfer coefficients expressed in the form of Nusselt number for the fluidized beds were found to be well correlated in terms of Archimedes number, the diameter ratio of particle to heated tube, and the density ratio of particle to working fluid.