Fan wet curtain cooling system is the most widely used in a greenhouse, the effect is significant A cool way optimum crop growth.
    Action principle
    When hot outdoor air is sucked through the wet curtain full of water absorption, wet curtain of water absorbs heat on evaporation, which reduces the temperature of the air entering the greenhouse. Typically, the wet screens, wet curtain of water distribution systems, pumps and tanks formed the wet wall along the side wall of the continuous construction of the greenhouse, while the fan is centrally disposed in the other side of the gable greenhouse. Wet curtain must be kept moist in order to ensure the completion of the process of evaporative cooling, according to the Regional Greenhouse size and which, in the appropriate choice of wind turbine installations across the wet curtain wall, so that the air flow smoothly through the greenhouse.
    Dryness of the air and evaporative cooling effect related to that poor air wet-bulb temperature and the dry bulb temperature related. Air dry and wet bulb temperature difference not only with geographical and seasonal variations, but the day also changed. Despite being one day dry-bulb temperature changes may be up to 14 ℃, but the magnitude of change in wet bulb temperature is only about 1/3 of the dry-bulb temperature. Therefore, in high humidity areas noon, evaporation system can still be cool, which is needed for the production of the greenhouse.