The characteristics of heat transfer on the horizontal tube bundles in a fluidized bed : for the case of large tube diameter φ90mm

This report presents the characteristics of the time-averaged heat transfer coefficient of the horizontal tube bundles in a fluidized bed, for the case of the relatively large tube diameter φ90mm experiment. The tube bundles have 4 rows and are in a staggered tube arrangement. Experiments were carried out on the two locations of the 1st row tubes (X1=110,250mm) from the distributor with varying superficial gas velocity (Uo) and static bed height (Lc). We found that when X1 was in a higher location the values of the heat transfer coefficients (Hm) increased. After the Hm has taken the maximum value, it will remain at the same value or will start to decrease. In the comparison between the results of the φ34mm and φ90mm tubes, there are many differences in the distribution of local H_θ, and on the average Hm it takes smaller values at similar conditions.