Experimental investigation of the influence of a stator vane damage on aerodynamics and aeroelastics of an HP turbine.
The LuFo-3 research project „RobustTurb" was dedicated to the analysis of rotor forcing due to in-service trailling edge damage of high pressure turbine nozzle guide vanes (NGV). Due to the extremely high temperature, which on average exceed the
Figure 2: Geometrically simplified damages
In figure 3, the results from the wake measurements for the configuration with a large triangular damage at center, conducted over 9 pitches, is shown. The third and fourth wake show the strongest influence due to the damaged vane, where wake number 4 belongs to the damaged stator vane itself, and wake number 3 is located on the pressure side direction and shows significant loss reduction near the casing. The other wakes remain nearly unchanged. Again a closeup using higher resolution measurement of the wake is shown in fig. 4.
Figure 4: Total pressure field (closeup view)
In cooperation with the Department Engine Acoustics the acoustic signature of the damage was investigated. The Institute of Aeroelasticity carried out own measurements to investigate the forced response of the adjacent rotor caused by the stator damage.