evaporative cooler; swamp cooler
A device that cools air by evaporating water; often used in dry climates. In Japan, sometimes marketed as a lower-power alternative to air conditioners.
An evaporative cooler uses the heat of vaporization of water to cool a room.
Evaporative coolers are effective in dry regions.
扇風機 is a simple fan that circulates air without cooling it, while 冷風扇 actively lowers temperature through evaporation.
Compound of 冷 (cool) + 風 (wind) + 扇 (fan), literally 'cool wind fan'.