Particle Deposition Characteristics on Turbine Blade Surface Based on Critical Velocity Model

Abstract

Based on the critical velocity model of EI-Batsh, this paper further considered the particle deposition-bounce and the secondary collision deposition after the bounced, which improved the original particle deposition model. Then the particle deposition mass per unit of time and area (PDM) was proposed to characterize the particle deposition on the turbine blade surface. The effects of different rows of cooling film holes, blowing ratios, particle diameters and diameters of cooling film holes on the particle deposition characteristics of the blade surface were then investigated. The results show that the deposition amount of the single cooling film holes opening with radial inclination facing the leading edge is the smallest, and the deposition amount gradually increases when the inclination angle is shifted toward the pressure and suction surface. As the blowing ratio increases from 0.3 to 1.5, the amount of particle deposition tends to decrease and then increase, and reaches a minimum value when the blowing ratio is about 0.5. The deposition increases with increasing particle diameters in the range of 2-10 μm and gradually increases when the diameter of cooling film holes is from 0.99 mm to 1.5 mm.