can you tell me some applications that you use fins in to enhance the heat transfer?

heat transfer - engineering

Automoble radiators . Air cooled air plane engines . Baseboard heaters . Air preheaters . Some boiler superheaters on the flue gas side

[1] The heat sink of the power transistors of an audio amplifier. [2] The oil tank of a 125 kVA power transformer. [3] The cylinder cases of a flat or radial engine. [4] The evaporator and condenser coils of refrigeration equipment.