An agricultural frost fan is a device used in the agricultural sector, primarily in fruit orchards and vineyards, to protect crops from frost damage during the colder months. Frost damage occurs when the temperature drops below freezing, causing ice crystals to form on the plant tissues, which can lead to cell damage and ultimately reduce the yield and quality of the crops.
Frost fans work by mixing the air in the field to prevent the formation of frost pockets or to raise the temperature slightly above the freezing point. They operate on the principle that the air near the ground is colder than the air above it during a frost event. The fans, typically powered by diesel or electric engines, are mounted on tall poles or towers and circulate the air by blowing it downward. This creates turbulence and mixes the warmer air above with the colder air near the ground, raising the overall temperature and reducing the likelihood of frost formation.
Frost fans are particularly useful in areas with frequent temperature inversions, where cold air tends to settle in low-lying areas. They are most effective when used in conjunction with other frost protection methods, such as overhead sprinkler systems or passive techniques like windbreaks and proper site selection.