JET ENTRANCE CONFIGURATIONS AND SWIRL MOTION EFFECTS ON HEAT TRANSFER CHARACTERISTICS INSIDE BLADE LEADING EDGE OF THE GAS TURBINE

In the present work a simulation is conducted by CFD to predict the cooling performance in a chamber with a swirl motion using nine shapes of injection entrances. The injection entrances are with different cross sections; rectangular (case A), circular (case B), half circular (case C), square (case D), elliptical ( case E), equilateral triangular (case F) and three configurations of convergent shapes (case G, H, I). The simulation is performed at constant hydraulic diameter for all shapes and at varied Reynolds number. The investigation parameters are temperature distribution in swirl chamber, circumferential and total velocities, circumferential and axially averaged Nusselt numbers, friction factor and thermal performance parameter. The results show that the temperature increases in all cases compared to the rectangular entrance shape. The convergent shapes give high performance in the heat transfer as well as high friction. Circular entrance shape has a higher circumferential and total velocity compared to all cases.