On a heat transfer surface, fins are provided to
Fins are used to increase heat transfer rate from a surface by
1. increasing the temperature difference
2. increasing the effective surface area
3. increasing the convective heat transfer coefficient
4. decreasing the thermal conductivity
Which of the above are true?
In order to achieve maximum heat dissipation the fin should be designed in such a way that it has
Fins are provided to a heat exchanger surface in such a way- that lateral surface area at root is maximum.
Two long rods A and B of the same diameter have thermal conductivities k and 4 k and have attached by one side of their ends inserted into a furnace at 400 K. At a section 1 m away from the furnace, the temperature of rod B is 120°C. At what distance from the furnace end, the same temperature would be reached in the rod A?
Fins are made as thin as possible to
A fin will be necessary and effective only when
where k = thermal conductivity of fin material, h = convective heat transfer coefficient between the fin surface and environment temperature
so, for more effectiveness, k should be large and h should be small.
Which one of the following statements is correct?
A fin of length L protrudes from a surface held at temperature to; it being higher than the ambient temperature ta. The heat dissipation from the free end of the fin is stated to be negligibly small.
The temperature gradient at the fin tip can then be expressed as
A fin protrudes from a surface which is held at a temperature higher than that of its environments. The heat transferred away from the fin is
Provision of fins on a given heat transfer surface will be more effective if there are .............. number of ................. fins.