Which Fan is Best for Cooling?
Everyone thinks of big air circulator fans when they want to get cool without air conditioning, but are these really the best ones to use? In some circumstances, the answer is yes – but there are a few exceptions to the rule. By knowing when it's better to use a different type of fan, you can ensure adequate cooling in many situations.
When the Air is Cooler than the People
As long as the air is cooler than the people who need relief, air circulator fans and drum fans are great choices. These work by increasing the evaporation of sweat from the body, which allows body heat to be dissipated into the air that is rushing by. Standard air circulators look like stereotypical fans, though the ones used in industrial locations can be much bigger. Drum fans, on the other hand, sit on the ground and have drum-shaped enclosures around their sides. This helps to direct air in a single direction. These fans are typically quite large.
Both standard and drum fans can be used outdoors as well as inside. However, with outdoor use, the wind from the fan may be diluted by natural winds. Therefore, people may have to come closer to an outdoor fan to feel an improvement.
Notably, once the air temperature reaches about 95 degrees, a standard or drum fan won't cool people down. Instead, it can actually heat them up! That's because heat transfers to cooler surfaces, and never the other way around. Normal human skin temperature is below 95 degrees, so heat will come to it from warmer air. In these cases, you need a different type of fan.
When the Air is Hotter than Human Skin
Even though the human body operates at between 97 and 99 degrees, the temperature of the skin is naturally lower. Therefore, if the air temperature is 95 degrees or above, it's time to bring in extra cooling power.
Evaporative coolers, also known as swamp coolers, take care of the problem by pulling air through a waterlogged pad. The pad pulls heat out of the air as the water in it evaporates. This brings the air to a temperature that will provide effective cooling to the people standing in front of the output side. In some climates, this provides enough cooling to avoid the need for air conditioning.
If your activity is taking place outdoors, evaporative coolers can still work. However, you can also make use of misting fans. These also use water to bring about the actual cooling, but instead of using a wet pad, they spray a fine mist that is picked up by the blown air. Heat still goes into the water, but this water will then land on everything in its path. Because of this, misting fans are preferred for situations where getting wet is not a problem. Sports teams love to cool their training areas with these systems.
As you can see, the situation dictates which fan is best to use. In relatively cool locations, a standard cooling fan works well. When it's hotter, go for an evaporative cooler or a misting fan.