AN EFFECT OF TURBINE BLADES SURFACES ROUGHNESS ON GAS POWER PLANTS AND PERFORMANCE DEGRADATION

The fuel contaminations and impurities leads to an extensive effects on the axial flow turbine for gas turbine engine of Iraq power plants, such as water content, Sulphur, sodium cause corrosion, erosion, and fouling which is the adherence of particles and droplets to the surface of turbine, i.e. (blade surface roughness) then turbulent boundary layer and its energy will increase. The gas station 35 MW was selected to determine the impact of this phenomenon on the performance of the station. Boundary layer separation take place early, flow deflection angle and blade efficiency were reduced, while the pressure loss coefficient and drag are increased. Turbine blade does not only reduce the aerodynamic performance, but the reduction in cross-sectional area of the turbine blade could lead to serious turbine damage. In this study, the relation between clean and rough turbine cascade will investigate to obtain aerodynamic behavior of both blades. A numerical solution (ANSYS Software) will use to simulate the test rig to predict the cascade blade performance and the upstream flow field, in order to achieve the main goals mentioned above. All the aerodynamic variables and parameters pressure and velocity distribution, energy dissipation, have calculated in the program energy dissipation were also calculated using numerical solution ANSYS software at wind tunnel Reynolds number of 1.783105 and3.566105.