Effect of solid particles on performance and erosion characteristics of a high-pressure turbine

The erosion caused by solid particles has been proved to be a great threat to the safety and reliability of turbine. With the aid of the Oka erosion model, the effect of particle size, blade tip clearance, and rotation speed of the rotor on erosion and performance of turbine is numerically investigated. Results show that the particle injection leads to a decrease of efficiency. The high erosion mainly occurs near the trailing edge at the pressure side and the leading edge at the suction side. With the increase of particle size, the erosion at the suction side tends to be more pronounced and extends to approach the leading edge. However, a small particle size causes more serious erosion at the pressure side. The erosion can be alleviated for larger tip clearances, because a widely-distributed passage vortex caused by larger tip clearances would impede the injected particles and alter the impact velocity and impact angle. With the decrease of rotation speed, the high erosion region extends to the leading edge at the pressure side, but the erosion at the suction side tends to be alleviated and even disappears. In addition, the off-design condition is found to dramatically decrease the efficiency and increase the erosion of turbine.