A Numerical Study of the Effect of Particle Size on Particle Deposition on Turbine Vanes and Blades

Abstract

Particle deposition could decrease the aerodynamic performance and cooling efficiency of turbine vanes and blades. The particle motion in the flow and its temperature are two important factors affecting its deposition. The size of the particle influences both its motion and temperature. In this study, the motion of particles with the sizes from 1 to 20 μm in the first stage of a turbine are firstly numerically simulated with the steady method, then the particle deposition on the vanes and blades are numerically simulated with the unsteady method based on the critical viscosity model. It is discovered that the particle deposition on vanes mainly formed near the leading and trailing edge on the pressure surface, and the deposition area expands slowly to the whole pressure surface with the particle size increasing. For the particle deposition on blades, the deposition area moves from the entire pressure surface toward the tip with the particle size increasing due to the effect of rotation. For vanes, the particle capture efficiency increases with the particle size increasing since Stokes number and temperature of the particle both increase with its size. For blades, the particle capture efficiency increases firstly and then decreases with the particle size increasing.

Corrosion behavior of Gd 2Zr 2O 7 thermal barrier coatings under Fe-containing environmental sediment attack

“…The coverage density of CMAS-Fe powders is 20 mg/cm 2 [43,44]. Four types of CMAS-Fe were applied onto the Gd 2 Zr 2 O 7 coatings using the leaky sieve method [45]. Firstly, the coverage quality of the CMAS-Fe powders was calculated based on the surface area of Gd 2 Zr 2 O 7 coatings and the coverage density of CMAS-Fe powders.…”

Effect of Carbon Particles on Aerodynamic Performance of a Radial Inflow Turbine in Closed Brayton Cycle

“…Compared with clean water condition, hydraulic efficiency of turbine under erosion condition decreases, and the particles mixed in liquid-phase will disturb the water flow distribution on the working side of blade. Liu [19] used the DPM model to simulate erosion of particles on turbine blades, and found that capture efficiency of blades increases firstly and then decreases with particle size. Yao [20] employed the same method and suggested that as particle mass flow increases, the DPM erosion rate of blade increases significantly.…”

“…Since carbon particles are mixed into fluid and the volume fraction of particles is small, the particle temperature and flow rate can be set to be same as the fluid. Particle size entering the turbine is generally concentrated in tens of microns (Liu et al, 2021;Hamed et al, 2006). In order to analyze the influence of particles on aerodynamic performance of turbine directly, the simulation with 0.5%, 5% and 10% mass fraction of carbon particles are carried out respectively.…”