Cooling methods for gas turbine blade leading edge: Comparative study on impingement cooling, vortex cooling and double vortex cooling

Abstract

To compare the behavior of different cooling methods for gas turbine blade leading edge, configurations of impingement cooling, vortex cooling and double vortex cooling are established. The coolant chamber is specially introduced to make models closer to real leading edge cooling system. Numerical computation is performed based on the 3D viscous steady Reynolds Averaged Navier-Stokes (RANS) equations and the k-ω turbulence model. Results show that the flow mass of nozzles in all configurations increases from upstream to downstream with the introduction of the coolant chamber. Besides, it is found that the anti-crossflow ability of nozzles is important to the flow and heat transfer performance. Lower crossflow velocity as well as smaller upwind nozzle area contributes to stronger anti-crossflow ability of nozzles. The vortex cooling proves to be a good cooling method with the highest heat transfer intensity and thermal performance factor, but its pressure loss is much larger. The middle-double vortex cooling is actually the optimization of the impingement cooling configuration and it has the lowest pressure loss. The tangential-double vortex cooling isn't applicable to leading edge cooling due to poor flow and heat transfer performance.