A fin array consists of 6 rectangular fins on a 2mm thick, 100mm by 180mm plate. The array is made of aluminum, and each fin is 30 mm long and 2mm thick. The array is attached to the surface of an electronics enclosure. The contact resistance between the surface of the enclosure and teh fin array is Rt,c = 5 X 10^-4 m^2 K/W.
The fin array is exposed to air at Tair = 20 degrees C with a convection coefficient of h = 40 W/m^2 K, and the fin array dissipates 130 W of heat to the convection enviroment.