Cooling method cools air with heat in water
Evaporative cooling uses the latent heat of evaporation to carry heat away from an object to cool it. Latent heat contains a considerable amount of energy, and carries away more heat than if the same temperature liquid was simply removed physically.
The sweat the body secretes to cool itself is a good example. The amount of heat transfer depends on the evaporation rate, which, in turn, depends on the humidity of the air and its temperature, which is why you sweat more on hot, humid days.
There are three kinds of conventional evaporative cooler designs:
- Direct evaporative coolers lower the air temperature by using the latent heat of evaporation to change water to vapor. The energy in the air does not change. Warm dry air is changed to cool moist air. The heat in the air is absorbed into water vapor.
- Indirect evaporative coolers use evaporative cooling to cool air, but then run that air or the water cooled by evaporation through a heat exchanger to cool supply air without increasing its humidity. The supply air doesn't get quite as cool, but it may feel more comfortable because it is dryer.
- The indirect/direct system combines the two systems by first using indirect evaporative cooling, then direct evaporative cooling on the air stream. This can produce supply air that is cooler than either direct or indirect alone. The IDEC’s relative humidity is lower than a direct system but slightly higher than an indirect cooling.
A fourth type of technology employs the Maisotsenko Cycle and indirect evaporative cooling. This system, used by Coolerado Cooler, can produce supply air that is cooler than all the other evaporative methods.
