Numerical Study of Swirl Cooling in a Turbine Blade Leading-Edge Model

In this paper, a numerical simulation is conducted to predict the swirl cooling performance of an internal leading-edge cooling passage model for a gas turbine blade. The swirling cooling performance and its effectiveness are investigated in the case of two rectangular section inlets that cause flow to impinge tangentially on the internal surface of the circular cooling passage. Parametric analysis on the local and average flows and heat transfers are performed at various Reynolds numbers, as well as the ratio of swirl chamber radius to jet slot height for a constant ratio of swirl chamber radius to jet nozzle length and constant jet nozzle area, respectively. The results indicate that the position of the swirl flow center is changing along the axial of the swirl chamber, and the swirl flow center of one constant axial section is not uniform as well in different ratios of swirl chamber radius to jet slot height. The larger ratio of swirl chamber radius to jet slot height and the higher Reynolds number are desirable to improve the performance of swirl cooling on the turbine blade leading edge, although the pressure loss of the swirl chamber will increase.