The effect of air flow on drying fodder on drying systems

Drying grass fodder in Europe’s Alpine countries is becoming increasingly important due to positive effects on the fatty acid composition of milk. A proper approach and technology of fodder drying can raise its quality to the level of grass silage. In principle, drying fodder means extracting water from fodder by means of ventilation – the air, the key to the speed of drying. Besides low relative air humidity, its flow rate through the fodder is also important. In the literature, the lower- and upper-bound limits of air flow rates can be found, with a difference of 85 % between the two. The article describes a test, measuring energy consumption and the efficiency of drying at a low air flow, often used in practice, and a high air flow. It was found that a high air flow results in 38 % higher energy consumption per kilogramme of extracted water, compared to a low air flow. The executed test has proved that drying at a higher air flow will not have a proportionally greater effect.