CHEE2695 – Lecture 7
Fins:
- Extended surfaces or fins are used to increase the effective surface area for
convective heat transfer.
- Fins can be classified into:
o Uniform cross section
Rectangular
Rod like
o Non-uniform cross section.
- From this, we get:
Where P=perimeter=2 w+ 2t .
, - The general solution of this is:
- For boundary conditions:
o At x=0 , T =T B .
o If the fin is very long,
o If the fin is of finite length, with an insulated end (adiabatic tip),
o If the fin is of finite length and there is heat loss at the end,
- The above equations ONLY apply for when the fin is of uniform cross section.
Non-uniform cross section:
- The differential equation for a non-uniform cross-sectional fin is:
Fins:
- Extended surfaces or fins are used to increase the effective surface area for
convective heat transfer.
- Fins can be classified into:
o Uniform cross section
Rectangular
Rod like
o Non-uniform cross section.
- From this, we get:
Where P=perimeter=2 w+ 2t .
, - The general solution of this is:
- For boundary conditions:
o At x=0 , T =T B .
o If the fin is very long,
o If the fin is of finite length, with an insulated end (adiabatic tip),
o If the fin is of finite length and there is heat loss at the end,
- The above equations ONLY apply for when the fin is of uniform cross section.
Non-uniform cross section:
- The differential equation for a non-uniform cross-sectional fin is:
