ISBN 9783843957267

978-3-8439-5726-7, Reihe Luftfahrt

Max Lorenz
Modelling the Geometry Change of Compressor Blades in a Cascade due to Solid Particle Erosion

107 Seiten, Dissertation Universität Stuttgart (2026), Softcover, A5

Zusammenfassung / Abstract

Performance degradation of aero engines due to erosion caused by particle-laden flow is a recognised issue which causes a significant increase of fuel consumption at a given operation point. A main problem is governed by the change of blade geometry due to solid particle impact. Since erosion research has not yielded a universally applicable model, accurate predictions necessitate measurement data thus making experimentally obtained erosion rates essential for models. These are frequently obtained from erosion experiments of flat plate specimen in specifically designed test apparatuses. This raises the question of the transferability of the data to other test rigs. Furthermore, in order to ensure its applicability in the modelling of the change of a surface due to solid particle impact, both the spatial and time discretization of a surface undergoing material removal has to be assessed. The integral parameter of erosion rate is obtained from many impacts and therefore a minimum impact count for its applicability must exist and is essential for modelling. Limits of the erosion rate applicability are derived using dimensional analysis and both a spatial and time discretization are found to enable its applicability. To provide measurement data for a comparison to the numerical prediction of the blade geometry a test apparatus is designed capable of eroding a blade set at controlled transsonic Operation conditions. In order to include blade-to-blade flow, a linear cascade is utilised. To evaluate the continuous change during erosion, the blades are removed at given intervals and scanned using a 3D scanning system. Furthermore the aerodynamic cascade characteristics are measured. The geometry data measured is then used as a test case for the prediction of the altered blade geometry due to solid particle impact. The predicted shape of the eroded blade geometry agrees well with the measured geometry data for all considered cases.