Evaporative cooling with misting: how does it happens? The fog physics

energy-evaporating-waterEvaporative cooling or adiabatic cooling, is the most well-known use of high-pressure water spray (misting).

The process of evaporation of the water absorbs energy (heat) from the surrounding environment thus reducing the temperature. For example, due to sweating and subsequent evaporation of sweat, you get the removal of heat from the body, and its temperature decreases. The water to evaporate therefore needs heat.

To better understand the process of cooling by evaporation of water in contact with the air, we can think of it as a sponge that is able to absorb, encompass, the water spray in the form of steam.

Naturally, this ability to absorb vapor of the air will be inversely proportional to the amount of water already present in the air itself, the relative humidity. In presence of low percentage of humidity, for example 30%, the amount of vapor that the air is able to absorb will be greater. Consequently, the evaporative process will be quicker and we’ll perceive a greater sense of well-being due to the better cooling of the surrounding air.

For the reasons above, we will obtain greater results and more benefits, through the evaporative process, in environments where there is a high temperature and a low relative humidity, up to a decrease in temperature which can reach 15°C.

The cold water does not increase the efficiency of an evaporative cooling system through the misting, because much of the energy required to evaporate it is necessary during the transition state between liquid and vapor. To understand this, just imagine the heat contained in a flame placed on a fire needed to make one liter of water to evaporate completely. The same energy is subtracted from the surrounding environment to evaporate the mist produced by MGF nebulizers.

What really matters is the ability to work at high pressures in a well-ventilated environments, to maximize the speed of the evaporation process. Thanks to the MGF pumps to spray and MGF spray nozzles, you can work at pressures up to 100 bar without any problem. The combination of high pressure and spray nozzles allows to reduce the water into fine drops and it then evaporate very quickly, before it falls to the ground.

The misting systems dedicated to cooling, can be installed in very different contexts always getting a significant drop in temperature without wetting. The temperature, in fact, can be lowered up to 15 ° C, with operation costs up to 5 times less compared to a conventional air conditioning system.

The MGF misting systems, thanks to an evolved electronic control technology, are able to properly balance the rate of humidity and temperature for a correct calculation of the heat index, the parameter that takes into account both the temperature and the humidity in the atmosphere for termo hygrometric wellness. In fact, when we have to cool in the presence of animals or people, it is necessary to properly balance the levels of temperature and humidity, otherwise there is a risk of not reducing or even raise the heat index.

The MGF misting systems have very low operating costs that allow the installation of these systems in any civil, industrial and agricultural use, providing excellent results and low costs.

The benefits are many:

  • increased comfort in the summer, thanks to the reduction of the temperature (outdoor cooling)
  • possibility to enjoy the sun without suffering the heat, so our sprayers are usually installed in swimming pools, beaches and gardens
  • removal of insects, flies and mosquitoes, with or without spraying chemicals
  • reduction of pollen and dust, thanks to the effect of the natural filter created by mist fog
  • low operating costs compared to the results obtained 

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