Two basic types of water cooling processes are commonly used. One transfers the heat from warmer water to cooler air mainly by an evaporation heat-transfer process and is known as the evaporative or wet cooling. These are also termed as open systems. The other transfers the heat from warmer water to cooler air by a sensible heat-transfer process and is known as the non-evaporative or dry cooling. These are also termed as closed cooling water systems because the water does not come in contact with outside air
