It should be noted that a specific volume of air (say, 1 cubic foot) at a certain temperature has the capability to hold a specific amount of moisture.
Increasing the temperature of that volume of air increases its capacity to carry more moisture, as shown in Figure 15-3.
It is noticeable that air temperature at Tdb2 is greater than at Tdb1.
As a result, air relative humidity (RH) at the higher temperature, RH2, is greater than that at the lower temperature,RH1.
This means that the air-drying capabilities could be increased by adding energy to the drying air.
As a rule, the drying time is reduced by passing larger volumes of air over soybeans or by increasing the air temperature, or both.
However, it should be mentioned that soybeans are sensitive to temperature fluctuations and can be easily damaged by air that is too hot or too dry.
Accordingly, the recommended minimum airflow rates for drying soybeans are shown in Table 15-1.