RADIATIVE HEAT-TRANSFER IN CIRCULATING FLUIDIZED-BEDS

The radiation contributions to heat transfer in circulating fluidized beds are investigated based on a simple model involving clusters and d ilute suspension. Local and length-averaged cluster transfer coefficie nts are derived based on a cluster renewal model with combined transie nt conduction and radiation. A three-component network is analyzed lea ding to a concise relation for the suspension-to-wall radiative transf er. Previous experimental data for heat transfer to a membrane wall wi th bed temperatures of 407 and 860 degrees C (Wu et al., 1989) are in goon agreement with model predictions.