As figure1 shows the typical structure and technological flow of evaporative cooler, its key feature is to intensify heat transfer by the evaporation of the water film on the exterior surface of the tube . Its working process goes like this: First, the pump moves the recirculating cooling water in the tank at the bottom of the equipment up to the spraying water distributor above the bare tube bundle. Then the spraying water distributor sprays the cooling water onto the exterior surface of the heat transfer tube, forming an even thin water film on the surface. Meanwhile the blower fan inhales air from the air inhaling window at the bottom, which drives the air current flowing upwards across the heat transfer tube. The heat transfer of the tube is thus enhanced by not only the sensible heat between the water film and the air current but also the great amount of heat absorbed by the evaporation of the water film.

	1 Blower Fan （Waterproof）
	2 Sprinkler System
	3 Tube Bundle
	4 Water Tube
	5 Water Circulating Pump
	6 Water Tank
Figure1 Structural Diagram of Evaporation Cooler

　　 Owing to the water