recommendation. Rough recommendations for hay drying, are a total pressure drop of 0.75 in. of water in selecting a fan for hay 15 ft deep. For depths of 6 to 8 ft of hay a pressure drop of 0.5 to 0.6 in. may be used. The rate of air flow should not be less than 10 cu ft per sq ft per min. A higher rate is preferable.
An acceptable mathematical relationship of the variables is: