On heat transfer surface, fins are provideda)To increase temperature g...
Ans. (c) By the use of a fin, surface area is increased due to which heat flow rate
increases. Increase in surface area decreases the surface convection resistance,
whereas the conduction resistance increases. The decrease in convection
resistance must be greater than the increase in conduction resistance in order to
increase the rate of heat transfer from the surface. In practical applications of
fins the surface resistance must be the controlling factor (the addition of fins
might decrease the heat transfer rate under some situations).
View all questions of this test
On heat transfer surface, fins are provideda)To increase temperature g...
Explanation:
Fins are thin metal extensions or projections that are attached to a heat transfer surface. They are used to enhance the rate of heat transfer from the surface by increasing the surface area available for heat transfer. This is achieved by increasing the effective surface area of the heat transfer surface.
The fins are designed to increase the heat transfer rate by promoting convective heat transfer. The fins increase the surface area available for heat transfer, which increases the rate of heat transfer. The fins also promote the formation of boundary layers, which increases the rate of heat transfer by promoting convective heat transfer.
The following are the reasons why fins are provided on heat transfer surfaces:
1. To increase the surface area available for heat transfer: Fins increase the surface area of the heat transfer surface. This increases the amount of heat that can be transferred from the surface. The greater the surface area, the more heat can be transferred.
2. To increase the rate of heat transfer: The increased surface area provided by the fins allows for more efficient heat transfer. This is because the fins increase the area of contact between the heat transfer surface and the fluid being heated or cooled. Therefore, the rate of heat transfer is increased.
3. To reduce the temperature gradient: The fins reduce the temperature gradient between the heat transfer surface and the fluid being heated or cooled. This is because the fins distribute the heat more evenly across the surface, allowing for a more uniform temperature gradient.
4. To reduce the pressure drop of the fluid: Fins are designed to minimize the pressure drop of the fluid being heated or cooled. This is because the fins promote a more uniform flow of fluid across the heat transfer surface, reducing turbulence and minimizing pressure drop.
Conclusion:
In conclusion, fins are provided on heat transfer surfaces to increase the surface area available for heat transfer, increase the rate of heat transfer, reduce the temperature gradient, and reduce the pressure drop of the fluid.