Evaporative Misting Cooling Systems
WHY MISTING, WHY COOLING WITH WATER?
Firstly, we must explain ‘Why cooling?’. We may start to the explanations by bringing a fact to your attention, which you may find interesting. The global warming, as being a frequently mentioned concept, a problem encountered and one of its main causes of overtemp that leads to holocaust in which the died people is expressed by thousands; it is still, even in developed Europe countries, there is no legal value put into effect and under control!
About this issue, we are sharing Nasa’s study that proves manpower loss due to high temperature of working places and a chart that shows human risk levels depend on temperature / humidity ratios. When you examine these, you will understand easily how important is the issue, in terms of both loss of production and health.
**This chart is taken from "US Department Of Commerce / National Oceanic and Atmospheric Administration - NOAA's National Weather Service"
Now, we can turn back to our ‘Why Misting, Why Cooling with Water?‘ issue.
Because the source of inspiration is nature, that’s why it is natural and healthy. Furthermore, for the outdoor and industrial places, which can not be cooled by conventional systems, it is the only solution and also it is very economic. This system's regional and personal usage is also possible.
Evaporative cooling system has two different application tecniques.
First is Paper Pad + Fan system, which could be also named as passive system:
As it clearly seems on the symbolic display above; while the ambient air, which passes through the wet pad, and the water on the pad are evaporating, the air temperature is decreasing. In this system, not only the intake air, but also dust and particles of the ambient air are cleaned by wet pads. The system has the possibility of both applying as a fixed system like roof or sidewall and window, and applying as mobile systems with high flow.
The second system is 'Misting System', which is named as active system.
Click on the image to zoom...
As you see in the images above, for the cooling based misting system; water is pushed in pulverised form to the environment by high pressure pump (60 /70 bar), which has 0.15 / 0.20 / 0.30 mm nozzle sizes. The water particles, which's sizes are minimised between 5 - 10 micron, will subject to the sudden flash evaporation by the high outdoor temperature. As the useage of outdoor air heat to vaporize the water droplets, the air temperature will drop dramatically and cool the environment. Wetness is out of question for this application, because of reduced droplet size and flash evaporation. In case of low pressure systems, the water particles size may reach to 100 micron and bigger sizes. As a result of increasing weight, and gravity effect, they can not have an opportunity to vaporise and settled to the any close surface and floor. So this may lead to wetness.
As being valid for both of the two evaporative systems; these systems' cooling capacity, which depends on ambient temperature and humidity ratios, is shown on the chart.