Near-Stall Modal Disturbances Within a Transonic Compressor Rotor
Abstract
This research effort seeks to better understand non-periodic flow characteristics for a forward swept axial transonic compressor rotor when operating near stall. Improved performance of a military gas turbine engine may be achieved by better understanding the mechanisms responsible for near-stall non-periodic disturbances within a transonic compressor rotor. Using pressure transducers, embedded within the rotor wall casing, data were acquired and calibrated at various speeds up to 90% of maximum rotation velocity. Within the 90% design speed, various data sets were acquired for different throttle configurations. A new method to post-process the data to allow better investigating of the non-periodic flow characteristics was developed. Using Fast Fourier Transforms, two distinct and dominant frequencies were identified and analyzed. Contour pressure distribution maps for varying throttle configurations; and the amplitude differences for each frequency of interest was generated to illustrate correlations in frequency strength and its relationship with tip-leakage vortices, normal/oblique shocks, and passage-to-passage interactions. This study uses effective instrumentation and robust data reduction techniques to successfully identify passage-to-passage distribution of non-periodic and periodic low dominant frequencies within the rotor blade passage prior to stall.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 2011
- Accession Number
- ADA556491
Entities
People
- Andrea Londono
Organizations
- Naval Postgraduate School