Dynamics of Resonant Surge/Stall Interactions in Compressor Models

Dr. Brianno Coller
California Institute of Technology 

Sponsored by the Department of Engineering Mechanics

Date:  Tuesday, November 12, 1996
Time:  3:30 p.m.
Place:  306 Bancroft Hall
 

In axial flow compressors there are two primary modes of instability: axisymmetric flow oscillations (surge), and asymmetric traveling wave disturbances (rotating stall). Since the occurrence of either during normal operation of jet aircraft engines could likely lead to catastrophic consequences, aeroengines are typically over-designed to obviate such possibilities. 

Recent efforts, via active control, to suppress the instabilities and allow for more efficient designs closer to the stall/surge boundary have achieved only modest success. Difficulties arise when both modes are nearly critical, leading to complex interactions between the two types of behavior. In this talk, I present some work in progress on understanding these interactions. In the analysis, we uncover a (quasi-) global resonant structure that can be exploited for control purposes. New challenges concerning the practical application of dynamical systems techniques to engineering systems emerge as well.