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Cooling towers are part of air conditioning systems or heat exchangers that focus on cooling inlet water. This inlet water is actually the amount of water that has reached a high temperature in the process of ventilation systems or industrial activities and has lost its ability to do work. Instead of being thrown away, it enters the cooling towers and returns to low temperatures to return to the activity cycle.
Different criteria and factors in the category of cooling tower types
- Function
- For the movement of air and water
- Type of air suction
- Circuit structure and assembly
- Appearance
- Body Material
Types of cooling towers in terms of function, opposite and cross
In general, two types of opposite or cross-currents are defined for air and water in different types of cooling towers. In cross-cooling towers, air and water flow intersect; In this way, air enters the tower from the sidewalls and water is sprayed from above and vertically inside. Due to the gravity of the earth, this water moves down automatically and is completely in contact with the molecular structure of air.
Opposite performance
Opposite flow for cooling towers also means that water enters the tower from above and air from below. Along the air path that is to be led to the top of the tower by the fans, there is water that is directed downwards due to the gravitational force of the earth. In this way, most of the contact between the weather takes place and causes the water to cool completely. It can be said that the cooling towers of the opposite stream are one of the most efficient types of towers due to the maximum contact with the air.
Air suction flows in cooling towers
- Natural flow
- Mechanical current (two types of forced and inductive)
- Composite flow
Natural flow
Types of cooling towers in their natural flow do not use any impellers to rotate and allow air to flow naturally into the tower and rise upwards, ending this process. Naturally, these types of towers have poorer performance and are not controlled. Therefore, wind and environmental factors can affect the performance of this tower. These types of cooling towers have a lower price than other cooling towers.
Mechanical, inductive and forced current
Mechanical flow in cooling tower types means that one or more impellers are used to circulate air in the towers. These types of towers are divided into two types by induction and forced by mechanical flow, which is located in the air outlet and inlet path, respectively, based on the location of the impeller.
Composite flow
The type of composite flow cooling tower is such that it has inherited its appearance from natural cooling towers with some lower height, but inside its building, it has placed butterflies for airflow.
Classification of cooling tower types in terms of circuit structure and assembly
Heat transfer in cooling towers takes place in various forms in the form of various circuits:
- Wet circuit or open circuit
- Closed and dry circuit
Wet and open circuit, direct weather contact
Open Circuit Cooling Towers In the case of cooling towers, these are actually the towers that have been talked about so far and are commonly known. In this way, water comes out of the pipe and is sprayed directly into the cooling tower. The basis of open circuit towers is evaporation. One of the significant disadvantages of open circuit cooling towers compared to closed circuit towers is that direct contact with the weather causes impure water to enter and this impurity eventually settles on the system.
CCTV cooling towers, the enemy of rust
In contrast, CCTV cooling towers use coils inside and do not expose water to direct contact with air all the time. Dry cooling towers, as mentioned, do not face water deposition, and this helps to prevent rust and the long life of the device.
This type of cooling tower has a higher price; Because they use fan coils!
Also, because they require two powerful pumps to start, they consume more power. More equipment in CCTV towers makes them more difficult, time-consuming and costly to repair. Another disadvantage of CCTV towers is related to the existence of fan coils and how the tower works; That is, their efficiency decreases with increasing ambient temperature.
Dry cooling towers, indirect weather contact
Dry cooling towers are a type of CCTV cooling tower. In dry cooling towers, it is not the water that is responsible for transferring heat to be in the cooling process. In fact, whether contact is indirect. In this way, coils are installed inside the dry cooling tower and water enters these coils. Air is then passed through the coils to reduce the temperature inside the coils. Therefore, in dry cooling towers, the main task is to carry the air and save water significantly. Therefore, this tower can be useful for areas with water shortages. This type of tower can be used for water that has a very high temperature and in the first stage, this water is introduced into this type of tower.
What is the difference between the appearance of cooling towers?
Depending on the location used, its geographical and climatic conditions and the amount of free space available and the differences between different types of air conditioning systems in each climate, different types of shapes that are available for cooling towers are used. The existing shapes of these towers are cubic, hyperbolic and conical.
Cone towers in houses
Conical or round towers are mostly used for domestic purposes and have a low price. Of course, in case of problems such as broken parts or sediment, repair work on these towers is a difficult task and the entire body of the tower needs to be opened.
Cube towers, better quality and easier repairs
Cubic cooling towers are of better quality than the previous ones and are used for more serious and industrial applications. Also, they are easier to clean and repair and take less time.
A hyperbolic cooling tower operates with a natural flow. But the geometric shape of the tower is designed to increase the efficiency of the tower. These types of towers, which transmit heat in the form of CCTV, play an important role in the industry and are used in larger quantities in combination.
Classification of cooling tower types in terms of body material
Different materials such as concrete, wood, galvanized and fibreglass cooling towers are used to build cooling towers.
