Evaluation of aerodynamic coefficients of high temperature gas turbine cascade of cooled blade

الملخص EN

The aerodynamic force coefficients of five linear cascade of existing film cooling turbine blades are evaluated numerically.

The blade is geometrically identical to the first rotor blades of the high pressure (HP) turbine of the F-100-PW-220 military turbofan.

Cascade turbine blade test rig has been designed, constructed, and calibrated to introduce experimental work for the same flow conditions of the numerical solution to validate correctness of the numerical results.

The numerical simulation shows acceptable agreement with experimental.

Also it was found experimentally that both lift and drag coefficients are increased slightly with add of film cooling.

The local Mach number distributions outside the boundary layer on both blade sides of the cascade blade are evaluated numerically and compared with the results of well-known CFD code (Fine / Turbo) for existing gas turbine rotor stage of identical blade.

The computational results obtained for both cases show that the Mach number distributions trend along both blade sides for rotor stage and cascade are approximately the same, and the values of Mach number of rotor stage are higher than that for the corresponded cascade.

Also it was found that the Mach number distributions on both blade sides are reduced in values by the addition of air cooling, and the local Mach numbers for the cascade case is reduced in values among the rotor stage for the two cases with and without film cooling on both blade sides.