EXPLORING THE EFFECTS OF PIN-FINS IN A GAS TURBINE BLADE INTERNAL COOLING CHANNEL

The narrow cooling passage of the internal section of the turbine blades is one of the complicated zones of the gas turbine system. It confronts a high temperature. Pin-fins are an excellent structure to insert in this section to ensure effective cooling. It accomplishes a higher heat transfer coefficient. Pin-fins are also implemented as a mechanical structure to bridge the thin metallic pressure surface and suction surface. However, the pressure drop is significantly higher in the case of pin-fin cooling, which can lower the thermal performance of the cooling channel. The optimization of pin-fin design is important to find the optimal pressure drop. The present study considers two different pin-fin designs, i.e., partial spherical and dome with different arrays of pin-fins. The experimental and computational investigation was conducted with rotation numbers ranging from Ro=0 to Ro=0.13. The experimental study was conducted with Reynolds (Re) numbers ranging from 9,000 to 50,000. A computational study was conducted with the Large Eddy Simulation (LES) technique. The final judgment was completed based on the cooling channel's heat transfer coefficient, friction factor, and thermal performance. The cooling channel with dome-shaped pin-fins with an array of 14x2 pin-fins showed a better thermal performance than other cooling channels.