Experimental Investigation of Heat Transfer to a Metallic Rodin a Fluidized Bed of Small Particles

The effect of heat carriers on heat transfer to a cylindrical metal bar was investigated in a lab setup fluidized bed with small spherical solids (2.7 mm glass beads and steel balls). Rods of aluminum and steel, each with 10 and 20 mm diameter and 60 mm length, were heated by means of hot air. In each experiment, the temperature of the center of solid was measured at various intervals of time. The effect of various parameters such as air velocity, air temperature, mass ratio of fluidizing material to solid, type of fluidizing material, diameter of fluidizing material, and diameter of solid were investigated. The rate of heat transfer increases with decreasing immersed solid diameter, increasing the fluidizing material thermal conductivity, decreasing fluidizing medium size, and increasing air temperature, but air velocity and amount of fluidizing material must be optimized to convert the system to a well-fluidized system and maximize the rate of heat transfer.