Areal parametric characterisation of ex-service compressor blade leading edges

Abstract

a b s t r a c tIn-service the degradation of compressor blade leading edges can have a disproportional effect on compressor efficiency. The high surface curvature in this region makes quantifying the surface finish of this sensitive and prominent region difficult. An automated technique that characterises the roughness of the leading edge in terms of areal parameters is presented. A set of ex-service blades of differing sizes are used to demonstrate the procedure. Improved characterisation of this blade region will allow engine companies to better understand where in-service deterioration has the greatest effect and inform them as to how they might minimise the effect. The present work shows that the leading edges of compressor blades exhibit a significantly higher characteristic surface roughness than other blade regions, and the spatial distribution of peaks in this characteristic roughness is detailed. In addition it is shown that peak wear and roughness are not uniformly correlated.

Leading edge topography of blades–a critical review

“…Similar or even larger changes to leading geometry may occur in service due to either additive or subtractive processes (i.e. erosion or deposition) [108]. Walton et al [108] presented a study that focused on the leading edges of the rotor blades from a single engine; measurements were taken from one blade from each row of the IPC and one from each row of the HPC.…”

“…erosion or deposition) [108]. Walton et al [108] presented a study that focused on the leading edges of the rotor blades from a single engine; measurements were taken from one blade from each row of the IPC and one from each row of the HPC. This allowed him to study leading edge of different sizes as well as different levels of degradation.…”

“…Figure 16 Generic compressor blade nomenclature; (1)-side view and (2)-tip view(x section) showing; LE-leading edge, Atip, B-root, C-chord (chordwise direction), TE-trailing edge, D-Span (spanwise direction), SS-suction side (convex), PSpressure side (concave), E-end wall[108].…”

“…In blue are regions of (relative) pronounced increase of fitted radius due to erosion of profile. Above and below are leading edge fields from the numbered blades in the LE positions indicated by the white lines[108]…”

The Use of Focus-Variation Microscopy for the Assessment of Active Surfaces of a New Generation of Coated Abrasive Tools

“…FVM is not only relatively new but includes the most dynamically developing measurement techniques of the last several years. Application of these techniques in a number of modern scientific and technological fields can be found in the literature [22][23][24][25]. Moreover, in abrasive machining technologies many applications occur that relate to the assessment of the condition of the machined surface [26][27][28][29] and the condition of the abrasive tool's active surface [30][31][32][33].…”