How HVLS fans work
HVLS fans work on the principle that cool moving air breaks up the moisture-saturated boundary layer surrounding the body and accelerates evaporation to produce a cooling effect. Ceiling fans create a column of air as they rotate. This column of air moves down and out along the floor. This deep wall of horizontally moving air is called a horizontal floor jet and is relative to the diameter of a fan and, to a lesser extent, the speed of a fan. Once the floor jet has reached its potential, it moves outwards until it meets a side wall or other vertical surface.
Under the ideal conditions, an 8ft (2.4 m) diameter fan will produce a floor jet approximately 36 inches(910 mm)deep. A 24ft (7.3 m) diameter fan produces a floor jet 108 inches (2,700 mm) deep, high enough to engulf a person standing on the floor or a cow, its original design purpose.Commercial HVLS fans differ from residential ceiling fans in diameter, speed and power. While some fans use modern blades to move air, other methods are used to make it more efficient, such as the use of airfoils.