The Evaporative Cooling Process is a cooling process that employs water as its refrigerant, which has a substantial benefit and is environmentally beneficial.
Evaporative cooling is based on the idea of water evaporation. Water absorbs heat from the entering air and evaporates it. Evaporation both cools and humidifies the air. Because of its low energy usage, this cooling technology is highly popular in hot and arid areas.
The release of perspiration from the human body and the subsequent cooling of the body due to evaporation is an example of evaporative cooling. This natural phenomenon of managing body temperature is found in all animals.
A fan or blower is used to take warm air from outside and convey it across wet pads that offer enough surface area for water to evaporate. The Evaporative Cooling Pads are often constructed of materials such as Aspen Wool or paper celluloid pad.
Evaporative coolers, like traditional air conditioning systems, can be installed as freestanding units or as ducted systems. Evaporative coolers can be roof-mounted, window-mounted, or ground-mounted. When installing a ducting system, it is best to attach it on the roof.
Because the system requires continual water make-up as it evaporates, water quality is critical. Hard water will create scaling on metal components. Scale deposits occur in the pads as well, and over time. This causes an uneven distribution of water across the pads, resulting in hot patches and efficient cooling. To address the issue of high mineral build-up in the re-circulating water, a water bleed-off line is added to drain a portion of the water on a intermittent basis.
Another large-scale application of evaporative cooling is in industrial cooling towers. In a cooling tower, the flowing water that picks up heat from industrial processes via heat exchangers is rejected into the environment.
The heat rejection process is accomplished by spraying water over a vast area using water distribution nozzles and a piping system, and the water is collected in a basin below. Water evaporation is induced using natural convection or an induced draught fan, depending on the cooling tower design. A cooling tower may accomplish a temperature decrease of 6-10° C depending on the delta difference between the temperature of the entering water and the temperature of the atmosphere, as well as the relative humidity.
What Is Evaporative Cooling?
Evaporative cooling uses far less energy than traditional refrigeration to chill the air.
Water evaporates in a stream of air during this process, and the liquid-to-vapor phase transition occurs. Sensible heat from the surrounding air is used in the process as essential latent heat for water evaporation—the loss of energy from air leads in a decrease in air temperature.
This cooling technology is both energy efficient and extremely sustainable, ensuring a productive, pleasant, and clean working environment within an office building, manufacturing facility, or distribution centre. In compared to conventional mechanical cooling systems, the Evaporative Cooling technology utilizes much less energy while producing the same or more efficient cooling capacity as traditional cooling methods.
The Evaporative Cooling system does not use heated polluting indoor air, resulting in 100 percent fresh and pollution-free air within a room or structure.
However, evaporative cooling has drawbacks, the most notable of which is lower efficacy when ambient humidity is high. Water evaporation becomes difficult in high humidity circumstances, particularly when relative humidity is near to 100%, since the atmosphere is already saturated with moisture.
As a result, cooling capacity plummet dramatically. More significantly, when evaporative coolers are used in residential areas located in hot humid circumstances, the increased moisture content of the air makes the atmosphere more unpleasant for human habitation. Maintaining constant high humidity levels promotes the growth of mould in home objects.
Exemplifications Of Evaporative Cooling
The following are some instances of evaporative cooling:
- In the heat, water in an earthen pot stays cold because the pot has fine pores through which water inside the pot evaporates.
- When we sweat, the water droplets on our skin evaporate, and we experience a comfortable temperature.
- The natural evaporation process is also used to recover salt from saltwater.
- When we apply nail polish remover to our nails, we feel cooler because the acetone in the remover absorbs heat from our bodies and evaporates.
