The temperature of the surface to which a circular blade with a diameter of 5 mm and a length L is attached is Tb = 100 °C. The temperature of the fluid around the fin is Tinfinite = 25 C, the convective heat transfer coefficient is given as h = 100 W/m2K. The material of the fin
a) Stainless Steel (k = 14 W/mK)
b) If it was copper (k = 398 W/mK),
Find which length L can be considered infinite, according to the material. (Hint: While the tip of the fin is ideally 25°C when L goes to infinity, you have to assume the solution is at an acceptably higher temperature of your own choosing).