How finned tube heat exchangers for commercial dryers work?

How finned tube heat exchangers for commercial dryers work

Commercial dryers usually require a heat source to heat the air in order to remove moisture from the material. To achieve this, the dryer needs an efficient heat exchanger to transfer the heat. One common type of heat exchanger is the finned tube heat exchanger.

A finned tube heat exchanger is made up of a group of finned tubes arranged in parallel. The fins of which are fixed to the tubes by riveting or welding to increase the surface area and improve the efficiency of heat transfer.

The finned tube heat exchanger works by transferring heat from one fluid to another, which flows through the inside and outside of the finned tube respectively. One of the fluids flows inside the tube and is known as the inner tube fluid. The other fluid flows outside the tube and is known as the external fluid. Heat is transferred between the fluid inside the tube and the fluid outside the tube via the fins.

In commercial dryers, hot water or steam is usually used as the inner tube fluid. The fluid outside the tube is the air that needs to be heated. As the hot water or steam flows through the finned tube, it transfers heat to the fins, which in turn transfer it to the fluid outside the tube, thus heating the air and allowing it to flow through the drying chamber to complete the drying process.

It is important to note that the heat transfer efficiency of a finned tube heat exchanger is related to the number, shape and density of the fins, the fluid velocity and the heat transfer properties of the tube and fin material. Therefore, when designing and selecting a finned tube heat exchanger, it needs to be selected and optimised for the specific application requirements.

The advantages of finned tube heat exchangers include

Efficient heat transfer: Fin tube heat exchangers have a large surface area, which increases the heat transfer efficiency, resulting in efficient heat transfer.

Compact construction: Fin tube heat exchangers are compact and can be used in space-constrained environments.

Corrosion resistance: Fin tube heat exchangers are usually manufactured using corrosion resistant materials such as stainless steel and copper, which can effectively resist corrosion.

Easy to clean: The finned tube heat exchanger has a simple structure and is easy to clean and maintain.

Disadvantages of finned tube heat exchangers include

Higher cost of construction: Compared to other types of heat exchangers, finned tube heat exchangers are more expensive to manufacture.

Easy to block: Due to the large surface area of the finned tube, if the fluid contains a high level of impurities, it can easily lead to blockage of the pipe.

High requirements for fluid flow rate: The finned tube heat exchanger has high requirements for fluid flow rate, if the flow rate is too low, it will result in lower heat transfer efficiency.

When using a finned tube heat exchanger, the following matters need to be noted:

Selecting the right material: Select the right tube and fin material according to the characteristics of the fluid and the requirements of the working environment to ensure that the heat exchanger has good corrosion resistance and heat transfer performance.

Control the fluid flow rate: Controlling the fluid flow rate and ensuring that it is moderate will not only ensure heat transfer efficiency but also reduce the risk of tube blockage.

Regular cleaning and maintenance: Regular cleaning and maintenance of the finned tube heat exchanger is carried out to ensure its normal operation and extend its service life.