Experimental Study of Damper Position on Instabilities in an Annular Combustor
| Autor: | James R. Dawson, Nicholas A. Worth, Håkon Tormodsen Nygård, Marek Mazur |
|---|---|
| Přispěvatelé: | Department of Engineering Cybernetics [Trondheim] (ITK NTNU), Norwegian University of Science and Technology [Trondheim] (NTNU), Norwegian University of Science and Technology (NTNU)-Norwegian University of Science and Technology (NTNU) |
| Rok vydání: | 2018 |
| Předmět: |
[SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph]
Physics [SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment 02 engineering and technology Mechanics 01 natural sciences 7. Clean energy Damper [SPI]Engineering Sciences [physics] 020303 mechanical engineering & transports 0203 mechanical engineering Position (vector) 0103 physical sciences Combustor Combustion chamber 010301 acoustics ComputingMilieux_MISCELLANEOUS |
| Zdroj: | ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition, Jun 2018, Oslo, France. ⟨10.1115/GT2018-75070⟩ |
| Popis: | The present study experimentally investigates the effects of different circumferential damper configurations on the instabilities in an annular combustor. The combustor consists of multiple bluff body swirl stabilized flames. It is operated with an ethylene-air premixture at a power of 66 kW. Combinations of Helmholtz resonators are used as dampers circumferentially arranged around the combustion chamber. The tests are performed at operating conditions where the combustor is self-excited and characterized by a strong standing mode and periodic mode switching. For each test, the dynamic pressure is measured at different locations and overhead imaging of OH* of the entire combustor is conducted simultaneously at a high sampling frequency. The measurements are then used to compare the pressure fluctuations of the different cases in order to find the best positioning of the dampers. The azimuthal modes in the chamber are determined and the phase shift between OH* and pressure is analysed. Based on the Rayleigh criterion, these investigations allow us to find out if the dampers only remove energy from the pressure oscillations, or if they also influence the instability margins of the combustor and the flame dynamics. Finally, the results are compared with the theoretical findings in literature and observed discrepancies are discussed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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