The temperature of grain at the top of the bed is shown in Fig. 9. The heating of
the bed by direct radiation in the mixed-mode is responsible for the drying front at
the top of the bed. The grain temperature in the mixed-mode is higher than that in
the indirect-mode because evaporative cooling in the mixed-mode does not occur.
The effect of evaporative cooling in the indirect-mode dryer can be seen in Fig. 9
where the grain temperature is lower than the ambient temperature during the first
five hours of drying.