What are the working principles of closed cooling towers?
Author：Trlon Views: Time:2020-09-22
Closed cooling tower is an application form of tube-type indirect evaporative cooler. Its working principle can be divided into three parts of the cycle. Let me introduce to you what these three parts of the cycle are.
1. Primary heat exchange cycle:
When the circulating hot water on the primary side (external circulation) flows through the coil of the closed cooling tower, it is divided into three stages for heat transfer: (1) First a. The heat of the hot solution is transferred to the inner surface of the coil according to the convective heat transfer. (2) Heat conduction through the wall thickness to the outer surface of the coil; (3) Convection heat from the outer surface of the coil to the fluid water film outside the tube, and transfer heat from the water film to the air by volatilization and convection.
2. Secondary side pre-cooling cycle:
The third side (self-circulation) spray water is pumped from the water pan under the closed cooling tower to the water distribution system by the spray centrifugal water pump. After a unique all-seeing sprinkler sprays onto the radiating material, performs latent heat and sensible heat exchanger with air, flows to the coil group after pre-cooling, produces a smooth water film on the tube surface, and absorbs the heat transferred from the material in the tube Xie returned to the water tray again, and the cycle continued.
3, air circulation:
The fan sucks the unsaturated air outside the closed cooling tower into the tower. The airflow passes through the coil, the heat sink and the spray water on the secondary side for latent heat and sensible heat exchanger to absorb heat, and then passes through a unique water baffle. The gas and liquid are separated, and the moist air close to saturation is discharged out of the tower.