Numerical and Experimental Studies of Turbulent Heat Transfer in Inclined Pin-Fin Channels With a Wavy Endwall

Endwall heat transfer characteristics of inclined pin-fin channels have been investigated to improve the cooling efficiency of gas turbine’s combustor liners. The time-mean local Nusselt number profiles were obtained in high spatial resolution by naphthalene sublimation technique based on the heat/mass transfer analogy and large eddy simulations. Inclined pin-fin channels with a flat or wavy endwall were tested and compared with each other. As a result, the time-averaged heat transfer coefficient of the wavy endwall was found to be higher than that of the flat endwall due to flow separation and reattachment from the hill of wavy endwall. Surprisingly, the wavy endwall case shows less or at least the same pressure loss compared to the flat endwall case. Therefore, it can be concluded that wavy endwalls can realize better heat transfer with less pressure loss as long as the aim consists in enhancing the endwall heat transfer in inclined pin-fin channels.