Dynamic simulation of particle deposition on the blade leading edge with film cooling in gas turbines

Abstract

Particle deposition on the leading edge was investigated in gas turbines numerically. The research investigated the effects of the inclination angle and blowing ratio on the deposition thickness, and cooling effectiveness of the leading edge. Particles were released from the main inlet of the computational domain. The deposition on the leading edge was judged using the double deposition model. The results show that the deposition thickness is inversely proportional to the blowing ratio. The deposition thicknesses for 0°, 20°, 40°, and 60° inclination angles decrease by 7.82 %, 6.84 %, 7.44 %, and 5.34 %, with the increase in the blowing ratio from 0.5 to 2.0 at 30 s. The deposition thicknesses with four inclination angles decrease by 6.79 %, 7.24 %, 6.79 %, and 5.34 % by increasing the blowing ratio from 0.5 to 2.0 at 60 s. A region with a deposition thickness coefficient below 0.3 is located on the side of the leading edge. The area of the region increases with the increases of the inclination angle and blowing ratio. Compared with the deposition thickness of 0°, 20°, and 40° inclination angles, the deposition thickness of 60° inclination angle is the least with the blowing ratios of 0.5,1.0 and 1.5. The difference in deposition thickness at 60° and 20° inclination angles is 0.3 % with the blowing ratio 2.0. The inclination angle has little effect on the deposition thickness under the blowing ratio of 2.0. The cooling effectiveness decreases with the increases in the blowing ratio and inclination angle. The deposition thickness at a 60° inclination angle is lower than that at a 40° inclination angle. The best combination of inclination angle and the blowing ratio is 60° and 2.0 compared with others.