R.R. Jones, G.R. Lazalier

Turbine engines are routinely tested in altitude test cells to support the engine development process as well as propulsion system enhancements after entering service. For certain test installations, the high-energy engine exhaust stream may contain acoustic and/or fluid dynamic characteristics which can couple with the resonant modes of the test cell/exhaust gas management system to produce strong, undesirable pressure fluctuations. During testing of advanced technology engines equipped with both convergent axisymmetric and two-dimensional, convergent-divergent vectoring nozzles at the Arnold Engineering Development Center, such plume/facility coupling has been experienced. These interactions, whose onset was associated with specific and repeatable nozzle operating conditions (e.g., nozzle area ratio, vector angle, and pressure ratio) produced unacceptably high noise levels (165 - 170 db) within the facility exhaust system. Diagnostic testing in the fullscale environment was used to: (1) characterize the excited facility resonant modes, and (2) investigate the sensitivity of the interaction to selected nozzle and facility configuration changes aimed at suppressing the interaction. In addition, a computational study of the full-scale nozzle internal flow was undertaken in an attempt to identify fluid dynamic phenomena which may contribute to the interaction. Results from these diagnostic efforts are described along with preliminary results from a follow-on subscale test program. The objective of the subscale effort is replication of the fullscale event, thereby providing a mechanism for detailed study of the interaction physics.

DGLR/AIAA 14th Aeroacoustics Conference, 1992

Conference Paper

englisch

21,0 x 29,7 cm, 10 Seiten

DGLR-Bericht, 1992, 1992-03, DGLR/AIAA 14th Aeroacoustics Conference - Proceedings; S.785-794; 1992; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V., Bonn

NA

aeroacoustics, test facilities, turbine engines

Bibliothek

1992