Air Cooler

a unit for cooling the air supplied to a building or for dissipating the heat from machinery, furnaces, and other types of heat-producing equipment. Air coolers are used in ventilation and air conditioning systems for industrial, public, and residential buildings, as well as in cooling systems for electric generators, computers, and radio and chemical equipment. Air coolers may be of the surface, trickle, or combination type.

In recuperative surface air coolers the air reduces the temperature by transferring heat through smooth or finned (plane or tubular) surfaces that are washed on the opposite side by a coolant (ammonia or Freon) or secondary refrigerant (water or brines). In regenerative rotary or stationary air coolers the air dissipates the heat periodically to cooled layers made of metal or plastic sheets or grids, stone chips, or porcelain rings. In trickle coolers the air is cooled by water or brine sprayed from atomizers. The principles of the first two types of units mentioned above are incorporated in the design of the combination air cooler. Recuperative surface coolers and trickle coolers are the most widespread types.