As it has been said already, the performances of a free cooler system are strictly affected by thermal conditions of the external ambient air and by weather and geographical factors, so that their efficiency varies depending on seasonal changes. But free cooler systems can be strengthened using a thermal booster, being it an adiabatic system that tears down the inlet air temperature. It is also possible as a retrofit on existing plants.
This trick allows to extend the use of the free cooling also during the months with increasing temperatures, which normally would compromise the efficient performance of the free cooling solution. It consists in the integration of modules that vaporize water on the incoming ambient air, achieving a forced temperature’s drop. In fact, air gets humidified using a spray system of water droplets, which evaporate and thus steal heat from the air, tearing down its temperature by approximately 5/7° C.
The adiabatic boosting uses the evaporation latent heat, based on the same functioning principle of evaporative towers. Later on, this simple thermal boosting system can be ruled out at the end of the warm season.
The water feeding the spray system must be carefully treated in order to not damage nor scaling the thermal exchange pack of the air radiator/dissipator. Anyway, it will be better to spray the water only over the inlet section, avoiding the thermal transfer pack in order to prevent possible scaling and clogging issues.
With this simple and tiny solution, it’s possible to combine the advantages offered by air dissipators and evaporative towers: