COMPUTATIONAL ANALYSIS OF EFFECT OF PARTICLE INJECTION IN A RECTILINEAR TURBINE CASCADE

Abstract

Blade is the most important part of turbine. During the flow of working fluid various types of contaminants come in contact of turbine blades which give rise to the trilogy of “CDE” names corrosion, deposition and erosion. This decreases the strength and overall efficiency of blade as well as turbine. In this report the attention is focused on the variation of inlet velocity in the rectilinear turbine cascade with the injection of particles using FLUENT®. This report gives a detailed explanation about the effect of particle injection on blade length and profile loss coefficient with variation of inlet velocity. Two Dimensional geometry of rectilinear cascade with six blades is created in Gambit® 2.4.6 software and flow behaviour is analyzed using fluent 6.3.26. Air at inlet velocity 50m/s, 100m/s and 150m/s with injection of ash, steel and water particles of 50μm, 100μm, 200μm and 300μm is passed through the cascade. The profile loss is decreased by increasing the velocity for a blade span. In case of ash particles of 50μm, profile loss is 17.92% by increasing velocity from 50m/s to 150m/s, 17.89% in case of steel particles,17.15% in case of water particles. We analyze that the effected length on the suction and pressure side of the blade will increases by increasing the velocity and diameter of injected particles.