Heat transfer in a high temperature fluidized bed

The heat transfer characteristics between the bed and immersed tube in a hi gh temperature fluidized bed (7.5 cm I.D.x70 cm H) were investigated with s and and iron ore particles. The heat transfer coefficients were measured at operating temperatures of 200-600 degrees C and gas velocities of 1-10 U-m f. The bcd emissivity measured by the radiation probe was found to be 0.8-0 .9. The experimentally obtained radiative heat transfer coefficient was in the range of 30-80 W/m(2)K for the operating temperature of 400-800 degrees C and the contribution of radiation to total heat transfer was about 13% a nd 18 % for the operating temperatures of 400 degrees C and 600 degrees C, respectively.