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How do fans make you feel cooler?

how do fans make you cooler, fans actually add heat to a room. One way to think about it is like this: If you have a perfectly insulated room and you put an electric fan in it, then the room will get warmer. All the electricity that is driving the fan turns directly into heat.

So a fan does not cool the room at all. What a fan does is create a wind chill effect.

When weatherpeople talk about wind chill on a cold winter day, what they are referring to is how the wind increases convective heat loss for details on convection). By blowing air around, the fan makes it easier for the air to evaporate sweat from your skin, which is how you eliminate body heat. The more evaporation, the cooler you feel.

How does a water cooler air conditioner work? There are several different ways that water is used in air conditioning. The most common use is in cooling towers. A cooling tower can be any size, from really gigantic down to the size of an automobile.

In a cooling tower, air blows over water to create evaporative cooling, and this cooler water is used in the heat exchanger of, say, an air conditioner. A more direct form of evaporative cooling is often found in greenhouses, farmers' markets and chicken houses. In these kinds of systems, water flows over a mesh, and a fan blows air through the wet mesh into the building. Humid, cooler air is the result.

Fans are by far the most economical cooling option in terms of both purchase and running costs. Fans are cheap to buy and cost an average of two cents per hour to run.

Fans provide a cooling effect by moving air either around a room or a person. Fans do not reduce actual room temperatures or humidity levels.

The table below will help you choose the most appropriate fan to suit the size of the room you wish to cool:

Selecting the best fan size
Room Area (metres2) Ideal Fan Width (sweep)
Up to 10 900 mm (36 inches)
10-20 1200 mm (48 inches)
15-30 1400 mm (58 inches)
+30 Two or more fans

Types of fans

Portable Fans

Available in desk, box or pedestal models.
Look for a fan that oscillates (changes direction) and has a variable speed control.
Most suitable for personal cooling
Average purchase cost £20-£170.

Ceiling fans

Can be suspended in rooms with high ceilings.
Should be installed with a clearance of at least 2100mm above floor level.
Should be located higher than the light fittings to avoid flickering shadows, or you can install a unit with a light fitting attached..
If more than one fan is required, the spacing between fans should be as least three times the fan width.
A reversing function enables some fans to be used in winter to bring down the heat that builds up at ceiling level.
Look for variable speed control and curved blades to produce more air movement.
Average purchase cost £50-£200, plus installation.

Air has mass and thermal capacity. It transfers energy. It can be compressed. When it's compressed, air transmits hydrostatic pressure. Although it has a rather low specific heat, compared to other fluids, air is the most commonly used medium for heat transfer. It is available everywhere on the surface of the planet.

Air is usually taken directly from the surrounding atmosphere and returned to it with a revised thermal content. Materials or objects that are cooled or warmed are almost always immersed in air. Even if another medium is used to cool a heat source, the ultimate heat sink is still the atmosphere, and, even in that case, the secondary heat transfer path to the atmosphere is usually a moving air stream.
A standard density figure of 0.075 lb/ft3 is used to rate fan performance. The thermal capacity of air, based on that value, is 0.569 W•min/°C/ft3. For every cubic foot of air per minute in an air stream, 0.569 watts of power dissipated as heat are transferred for an air temperature change of one degree Celsius. The thermal capacity of air, when held at a constant pressure is often expressed as 7.59W•min/°C/lb.

Air Flow Rates and Package Layout

In electronic equipment and circuits, power dissipation is generally a stated condition; an air flow rate requirement is dictated by the need to keep the temperature of one or more of the components within specified design limits.