Principle of Cooling Towers
The water is an effective heat transfer medium and this is taken advantage of industrial water cooling towers. The heat received by the circulating water from various kinds of process equipments is dissipated in the cooling tower for being recirculated.

The cooling towers for water operate on the principle of heat dissipation through partial evaporation of the circulating water. The heat thus removed by the evaporation of water is called latent heat of evaporation.

Tonne of Refrigeration
Refrigeration effect equal to the melting of 1tonne of ice in 24hrs. This can be expressed as follows:

288000 Btu / 24hrs. or 12000 Btu / hr.


Principle of Cooling Towers
The water is an effective heat transfer medium and this is taken advantage of in cooling towers. The heat received by the circulating water from various kinds of process equipments is dissipated in the cooling tower for being recirculated.

The cooling towers operate on the principle of heat dissipation through partial evaporation of the circulating water. The heat thus removed by the evaporation of water is called latent heat of evaporation.

Calorie
The amount of heat required to raise the temperature of one gram of water by 1degree Celsius.

Range
The difference in temperature of the hot water entering the cooling tower and the cold water leaving the tower.

Approach
The difference between the temperature of the cold water leaving the tower and the wet bulb temperature of the air entering the tower.

Wet bulb Temperature
This is the lowest temperature water can be cooled by evaporation. Wet bulb temperature* is an important parameter in the cooling tower selection and design.

Heat Load
The amount of heat to be removed from the circulating water in an hour. Heat load is equal to the rate of water flow per hour multiplied by range.

Drift Losses
The water carried over and discharged to the atmosphere.

Blow Down Volume
Due to continued evaporation of circulating water in the tower the concentration of dissolved solids in the water increases. This is kept in check continuous bleed off of a part of the basin water.

Make Up
The amount of water required replacing the evaporation, drifting and blowing down volume. The quality of makeup water* should be with in the range specified.