ABSTRACT
Ambient air is a mixture of dry air and water vapor. Moist air is necessary in many unit operations. To work out such problems, it is essential to have knowledge of the amount of water vapor present in air under various conditions, the thermal properties of such a mixture, and changes in the heat and moisture contents as it is brought in contact with water or wet solid. Particularly in grain drying, the natural or heated air is used as a drying medium. Although the proportion of water vapor in air is small, it has a profound eect on the drying process.
