Heat Transfer and Friction Loss Characteristics of Pin Fin Cooling Configurations

Pin fin or full cross pin cooling configurations have long been of interest to the turbine cooling designer because of their potentially high heat transfer characteristics and high surface area density, as well as their structural and castability advantages. The pin fin cooling configurations consist of flow channels with circular pins extending from the walls into the channel flow. The pin fins function as turbulators to produce high heat transfer rate; however, their geometric arrangement must be optimized to avoid high friction loss. Experimental tests have been conducted to investigate the effects of pin heights, spacings, and channel height to length ratios to the heat transfer and friction loss characteristics of the pin fin cooling configurations. The test results indicate that the pin fin configuration provides a means to reduce the flow friction loss and yet to maintain a reasonably high heat transfer rate as compared to the cross pin configuration. The pin spacing in the test range shows less effects on the pin fin performance than the pin height.