HEAT TRANSFER IN SOUND ASSISTED FLUIDIZED BED OF FINE POWDERS : A REVIEW

Nanoparticles have a rare quality of very small size and a large surface area per unit mass. These are most advantageously used in many applications with their fluidization process. In such particles, for better fluidization process together with the conventional gas fluidization technique some additional forces were studied by many authors. One of them is application of sound waves. The presence of sound waves causes the decrease in the characteristic minimum fluidization velocity with increase in the heat transfer rate from heating element to very small sized particles of fluidized bed. The brief information about nano powders, fluidized bed and sound assisted fluidization process are given in the present article. Similarly, the heat transfer phenomenon in fluidized bed, the effect of sound field on fluidization of powder in presence of sound field, the measurement techniques in fluidized bed and design methods of heat transfer in fluidized bed are also presented.