Analysis of higher order Moore-Greitzer compressor models

Abstract

In this paper we investigate the behavior of higher order Galerkin expansions of the MooreGreitzer model of general transients in aeroengine compression systems. We assume steady state entrainment of the higher Fourier modes of the rotating stall cell which establishes a framework for a simplified numerical analysis of the bifurcating solutions corresponding to rotating stall. For small values of the Greitzer surge parameter ( B ) we discuss general trends in the character of the pure stall solutions. The rotating stall characteristic is shown to exhibit deep hysteresis with a cubic compressor characteristic, establishing the fact that deep hysteresis to a certain extent is a multi-mode phenomena. Elimination of the hysteresis associated with the bifurcation into stall is accomplished in simulations with a combined feedback on the displacement from the peak of the compressor characteristic and the magnitude of the first mode amplitude of the stall cell. Behavior for larger values of the B parameter is also investigated and novel surge/stall relaxation oscillations corresponding to classic surge are discovered.

Derivation of the viscous Moore-Greitzer equation for aeroengine flow

“…Banaszuk et al [2] gave the first result in this direction, see also Humber and Krener [16], [17], and Xiao and Basar [35], but Birnir and Hauksson [6] and [8] were able to use their qualitative analysis of the basic attractor to develop optimal control of stall. This control strategy that has been implemented by Fontaine [12] may eventually lead to jet engine design which is lighter and more fuel efficient.…”