Stall analysis in a transonic compressor stage and rotor

Download
Author
Davis, William L.
Date
2009-06Advisor
Gannon, Anthony J.
Second Reader
Hobson, Garth V.
Metadata
Show full item recordAbstract
Gas turbine engine design is based on simplifying assumptions, including axi-symmetric flow. These assumptions break down in the real machines especially when operating near to stall. The reduction in operating surge margin associated with current trends to develop high performance military fighter aircraft further highlights the need to develop a thorough understanding of the flow in rotor blade passages and especially when operating close to stall. This research investigates the behavior of a Transonic Compressor Rig (TCR) as it approaches stall in the rotor-only and full-stage configuration using combinations of frequency and time domain analysis in the subsonic (70% rated speed), sonic (80% rated speed) and transonic operating ranges (90%, 95%, and 100% rated speed). A steady-state analysis of the pressure measurements across a rotor passage of the TCR was conducted to identify potential pre-stall indicators, the structure of the flow field within the blade passages, and to correlate changes in flow structure with changes in pressure measurements. Further investigation using flow visualization techniques within the blade passages demonstrated how the TCR rotor departed from an idealized rotor when the axi-symmetric assumption holds when operating at steady-state and near stall conditions. This identification of potential stall indicators and characterization of the time variant flow field within the passages will impact future compressor design to enable operation closer to stall and increased performance across an operating spectrum.
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.Related items
Showing items related by title, author, creator and subject.
-
Pre-Stall Instability Distribution Over a Transonic Compressor Rotor
Gannon, A.J.; Hobson, G.V. (2009-05);An investigation of the behavior of a transonic compressor rotor when operating close to stall is presented. The specific areas of interest are the behavior and location of lowfrequency instabilities close to stall. In ... -
A MANUFACTURING PROCESS TO IMPLEMENT TRANSONIC COMPRESSOR ENDWALL CASING TREATMENTS
Green, Jeremy C. (Monterey, CA; Naval Postgraduate School, 2021-06);The goal of this thesis is to create a manufacturing process that will be used to implement transonic compressor treatments in the form of grooves or passages beneath the endwall surface. The main goal of the treatments ... -
Experimental investigation of high-pressure steam-induced surge in a transonic compressor stage
Hurley, Andrew M. (Monterey California. Naval Postgraduate School, 2008-06);Operational experience indicates that steam escaping from carrier catapults has the potential to induce stall or surge in the compressors of jet aircraft during takeoff. As the carrier fleet ages and the Navy transitions ...