With the advancement in computing power of computer and flow modeling software, simulation of turbo machinery is taking forefront. Validation of models can be done with few experimental results. Validated models then can be extended for correct flow parameters of turbo machine. Present work deals with the modeling of a rectilinear blade cascade using commercially available FLUENT code for roughness value up to 200 µm applied over entire blade surface. The computational outputs like static pressure distribution over blade surface, total pressure and outlet angle at exit measurement plane, mass averaged loss coefficient of the test blade channel for various level of roughness over blade surface are compared with wind tunnel experimental data. The computed data agree well with the experimental result.

Key Words: Steam Turbine, Blade, Roughness, Cascade.