Unsteady Swirling Flows in Gas Turbines
Abstract
The objective of the investigation is to acquire fundamental understanding of a phenomenon characterized by violent fluctuations occurring in swirling air flows in aircraft engines; this flow instability, dubbed here as 'vortex whistle', is known to be capable of causing severe fatigue failure in gas turbine components. in the present report period, the analysis started from the compressible unsteady Navier-Stokes equations; this was necessary in order to assess the importance of the so-called higher order effects in the boundary layer upon the streaming. Resorting to the apparatus of a matched asymptotic expansion, the analytical representation of the acoustic streaming was derived anew. The results are in essential agreement with our previous conclusions and we were able to confirm, on firmer ground, the existence of the threshold swirl beyond which the free vortex distribution changes into a forced vortex type; these are written up in a paper form appended to this report. Second, based upon the analytical results, a test rig with two different tangential injection manifolds was designed, constructed and installed; the acquisition of the data from them will form the central effort of the next, Phase II activity.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1980
- Accession Number
- ADA086765
Entities
People
- M. Kurosaka
Organizations
- University of Tennessee Space Institute