Fin is the extended surfaces that are specially designed to increase the heat transfer rate for a fixed temperature surface or lower temperature surface for a fixed rate of heat transfer. By the connection between the surface and the fluid surrounding, heat transfer can be increased by attaching to the surface known as fins. The heat-conducting through walls, boundaries, or solids has to be dissipated continuously to the surrounding to maintain the system in a steady-state condition. The fins raise the effective area of a surface so rising the heat transfer by convection. Fin press machine manufacturers deal with rectangular fin and triangular fin for heat flow per unit mass with ease of manufacture. The triangular type of fins is attractive as it requires less volume.
Types of fins:
There are four main types of fins:
- Variable area straight fin
- Constant area straight fin
- Annular fin
- Pin fin
Uses of the fins
- Generally, there are many uses of fins. Following some usage are mentioned:
- It is used as an economizer in a steam power plant.
- Role of convectors for hot water heating systems.
- Small capacity compressor
- Automobile radiators
- Fins are air-cooled engine cylinder head
- Bodies of electric motors
- Transformer equipment
- Electric equipment etc.
Materials of fins
- Aluminum alloy is one of the most common heat sink materials that has one of the higher thermal conductivity values. Mechanically, it is soft.
- Another is copper that has around twice the aluminum thermal conductivity. It is faster and more efficient heat absorption than aluminum. It is expensive as well.
The finned surface is commonly used to enhance heat transfer. This often increases the heat transfer rate from the several-fold surface. The car radiator is one example of a finned surface. The closely packed thin sheets of metal attached for convection, to the hot water tubes increase the surface area. Therefore, the convection heat transfer rate from the tubes to air several times. There are different varieties of designs of innovative fin available in the market.
Application of fins
Following are some examples of surfaces where fins are used:
- Engines of air-cooled I.C
- Tubes in refrigeration condenser
- Semi-conductor devices
- Automobile radiators
- Computer CPU heat sinks
- In power plants as heat exchangers
- Dry-type towers for cooling
- Electronic cooling components
- Reciprocating air compressors
- Electric transformers
- Also, use in modern technologies like hydrogen fuel cells.
Advantages of fins
The heat transfer rates by using the fins can increase, without any protective maintenance. For increasing the heat transferring rate, this is the cheapest way from the hot bodies. The effectiveness and efficiency of fin depend on the medium in which they are being used.
Disadvantages of fins
The length of the fin is directly proportional to the rate of the heat transfer. But unfortunately, the larger length of the fin is one of the causes of bending in the fins, this also increases the weight of the engine. Therefore the overall efficiency of the fin will decrease.Tags: Fin press machine manufacturers