Fig. 7shows the effect of inlet air temperature on the
heat transfer coefficient, indicating that the temperature
is not an important factor to improve the heat transfer
coefficient between the air stream and the solid particle.
The heat transfer coefficient in the downcomer is empirically correlated with the relevant parameters using the
same equation as Eq.(8). Thus,
Nud¼42.07Re
0;454
p;d
Hd
dp
1.006
R
2
¼0.91 ð9Þ
The range of applicability is: 150