Heat Transfer Between a Gas Fluidized Bed and Immersed Tubes

TLDR: In this article, the relationship between boiler tubes and the fluidized bed is empirically developed on the basis of the observed data with limited attention to the mechanisms of the heat transfer process.

Abstract: Publisher Summary Bed–to–surface heat transfer can be calculated with good reliability, if particle-residence times and their population near the surface are known The mechanism of heat transfer between boiler tubes and the fluidized bed is very complicated because of the many fluidized-bed variables and the variations in heat-transfer tube design Correlations are empirically developed on the basis of the observed data with limited attention to the mechanisms of the heat-transfer process This chapter reviews the design application of local as well as total heat-transfer coefficients for horizontal and slanted tubes, and for vertical tubes Single tubes and tube banks in different orientations to the bed are also considered The fundamental mechanisms of wall–to–bed heat transfer are reviewed and the criteria for evaluation of correlations for full-scale application are examined Particle movement is a complex function of the particle and gas properties, fluidization velocity, gas distributor, and geometry of the bed This approach generally gives the designer a good degree of assurance, requires a judicious choice of a representative system as well as the expense of pilot scale development The consideration must be given to the unsteady-state conduction component, the radiation component, and the gas convective component in boiler design