During on-wing time of a jet engine deterioration occurs and
leads to decreasing component efficiencies. This results in increasing
Exhaust Gas Temperature (EGT) and Specific Fuel Consumption
(SFC). Thereby, the condition of the High Pressure Compressor
(HPC) has a comparatively large influence on these parameters
defining overall engine performance. This can be explained by a
changing flow field in the HPC due to geometric deviations which
may occur during operation. The geometries are influenced by erosion
which results in thinner airfoils, changed leading- and trailing
edge geometries, shortened airfoils and increasing tip clearance.
The objective for future maintenance strategies is to determine
the influence of the different wear mechanisms. This can be done by
experiments and Computational Fluid Dynamics (CFD). Because of
the high number of different mechanisms and locations of deterioration,
CFD-calculations seem to be necessary to give a detailed view
of the influence of deterioration. In this regard, the following paper
will present a developed procedure for analyzing, manipulating and
meshing HPC-blades to simulate their flow. Therefore, three different
software-routines for the mentioned steps will be shown and
explained.
Additionally, an example blade will pass through the process and
will be manipulated for max. deviation caused by deterioration. At
the end, a CFD-calculation of these blades will be carried out and
analyzed for its aerodynamic behavior.
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