Cooling tower of the operation principle

When the working principle of water cooling tower is adopted, the cooling relationship and evaporative cooling principle of water cooling tower are more important.  

1. Heat dissipation relationship of cooling tower  

In the wet cooling tower, the heat dissipation of air has three forms: 

(1) contact heat dissipation  

(2) Evaporative heat dissipation;  Radiant heat dissipation.  

This heat dissipation method mainly uses the principle that the air temperature is lower than the high temperature water, and uses the heat transfer with the air to take the heat away from the air.  At present, the first two heat dissipation methods are mainly used for cooling water tower, and the radiation heat dissipation is very small, so it can not be ignored.  

2. Evaporation and heat dissipation principle  

Evaporation and heat dissipation are achieved by the exchange of materials, that is, by the continuous diffusion of water molecules into the air.  Water molecules have different energies.  Average energy depends on water temperature.  Some water molecules near the surface with high kinetic energy overcome the attraction of neighboring water molecules, escape the surface and become water vapor.  As the high-energy water molecules escape, the water near the surface becomes less energetic and, therefore, cooler, which is heat loss from evaporation.  It is generally thought that evaporated water molecules first form a thin layer of saturated air on the surface of the water at the same temperature as the surface of the water, from which water vapor diffused into the atmosphere.  The velocity depends on the difference between the water vapor pressure in the saturated layer and that in the atmosphere.  

After the fan draws in the dry air, it enters the cooling tower through the intake network.  High temperature water molecules with high partial pressure of saturated steam flow to low pressure air, while hot and humid water is poured into the tower through a self-seeding system.  When water droplets come into contact with air, evaporation occurs under the action of pressure due to direct heat transfer between air and water on the one hand and pressure difference between water vapor and air surface on the other, and heat in the water is taken away and evaporated.  Heat transfer, thus achieving the purpose of heat dissipation.