How does Evaporative cooling work? You need to be familiar with the properties of heat, air, and water vapor. Direct type is the most common Evaporative cooler. Here, hot outside air gets cooled inside the machine before being forced into the structure and then exhausted to the outdoors. There are two types: the Indirect and Air Washer types.
What Does Heat Mean?
Before we can get into the cooling process, let’s first understand what heat is. There are two kinds of heat. Sensible heat can be felt or sensed and Latent Heat cannot be detected using a thermometer.
“Evaporative cooler pads” describe the heat that is used to evaporate water. It could be heated from the hot asphalt that is used to evaporate water following a summer thunderstorm, or heat from a stove burner that is used to evaporate the water from a boiling pot. You can see liquid water changing into vapor. The temperature of the liquid water does not change. However, the molecular structures of the vapor reflect the heat and energy that it absorbs. The natural phenomenon called Latent Heat makes evaporative cooling possible.
Where Is Latent Heat From?
It is produced by the surrounding air and other materials. The environment heats a substance’s state, which can change from solid to liquid (ice and water) or liquid to gas (water to vapor, water to steam) when it changes. It means that surrounding air and solid objects, as well as liquids, become cooler due to their heat being emitted to the melting or evaporating process.
Total Heat is the combination of sensible heat (latent heat) and it. Total heat is the sum total heat in a given room. It includes both heat you can feel as well as heat you don’t feel. Single-water evaporates approximately 2000kJ worth of heat energy. This is without any external energy input. Evaporative air conditioners are very efficient in using little electricity. Only the fan and pump drive are powered by electricity.
The Evaporative-Air Cooling Process
Direct evaporative air cooling machines are enabled by water pumps that deliver water to cooling plates and a motor-driven fan, which forces hot outside Air through those media panels. These components are combined to speed up natural heat exchange.
The process involves some conversion of sensible heat (the heat that you can feel) into latent warmth (the heat that you don’t feel). This happens when the Water Cooler turns water into water vapour.
This is the process where sensible heat transforms into latent warmth. The hot air becomes colder as some of its (sensible), energy has been used. This causes the air to drop in temperature. The cold air then is pumped into the building. It is never reused.
Evaporative Air Coolers can slightly increase humidity within the building. But, it is also important to keep in mind that the temperature has fallen. Because they can create comfortable conditions, Evaporative Heat Coolers are widely used all over the world.
As the graph below illustrates, relative humidity and temperature have an inverse relationship. That is, relative humidity falls during warmer days. This is why Evaporative Heating technologies are more efficient when the temperature rises. The lower relative humidity makes it easier for evaporation.
Even in areas that are usually considered very humid, it is possible to cool down in the middle-of-the-day when the humidity and temperature combine.