Fin (extended surface)
In the study of heat transfer, fins are surfaces that extend from an object to increase the rate of heat transfer to or from the environment by increasing convection. The amount of conduction, convection, or radiation of an object determines the amount of heat it transfers. Increasing the temperature gradient between the object and the environment, increasing the convection heat transfer coefficient, or increasing the surface area of the object increases the heat transfer. Sometimes it is not feasible or economical to change the first two options. Thus, adding a fin to an object, increases the surface area and can sometimes be an economical solution to heat transfer problems.
General case
To create a tractable equation for the heat transfer of a fin, many assumptions need to be made:
Steady state
Constant material properties (independent of temperature)
No internal heat generation
One-dimensional conduction
Uniform cross-sectional area
Uniform convection across the surface area
