Experimental Study of Air-Cooled Parallel Plate Fin Heat Sinks with and without Circular Pin Fins between the Plate Fins

Experiments were conducted to investigate forced convective cooling performance of an air cooled parallel plate fin heat sink with and without circular pin fins between the plate fins. The original parallel plate heat sink was fabricated consist of 9 parallel plates of length 53 mm with cross-sectional area of 1.4 mm in width by 20 mm height for each plate. The second heat sink has the same geometry of original one but with some circular pins between the plate fins. Thermal and hydrodynamics performances of the heat sinks have been assessed from the results obtained for the pressure drop, thermal resistance and overall performance with the free stream air velocity ranging from 4.7 to 12.5 m/s. Results show that the free stream air velocity has a significant effect on the thermal and hydrodynamics performance of the system. With increasing free stream velocity, the heat transfer coefficient increases and consequently the thermal resistance decreases while pressure drop increases due to higher inertial of fluid at higher velocities. Furthermore, at the same free stream air velocity the thermal resistance for the heat sink with circular pin is about 37.7% lower than that of the original heat sink.