Zs. Spakovszky et al., Influence of compressor deterioration on engine dynamic behavior and transient stall-margin, J TURBOMACH, 122(3), 2000, pp. 477-484
Citations number
10
Categorie Soggetti
Mechanical Engineering
Journal title
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
This paper presents an experimental and analytical investigation of compres
sor stability assessment during engine transient operation. A two-dimension
al, linear, compressible, state-space analysis of stall-inception (Feulner
et al., 1996, ASME J. Turbomach., 118, PP 1-10) was modified to account for
engine transients and deterioration, with the latter modeled as increased
tip-clearance and flow blockage. Experiments were performed on large commer
cial aircraft engines in both undeteriorated and deteriorated states. Un st
eady measurements of pressure in these test engines during rapid accelerati
ons revealed the growth of pre-stall disturbances, which rotate at rotor sp
eed and at approximately half rotor speed. These disturbances are stronger
in deteriorated engines. The model showed that the signal at shaft speed wa
s the first compressible system mode, whose frequency is near shaft speed,
excited by geometric nonuniformities. The computed behavior of this mode du
ring throttle transients closely matched engine data. The signal increased
in strength as stall was approached and as the engine deteriorated. This wo
rk firmly establishes the connection between observed signals in the these
engines and first principles stability models. [S0889-504X(00)01603-2].