High-Frequency Transverse Acoustic Coupling in a Multiple-Injector Cryogenic Combustor
| Autor: | Philippe Scouflaire, Sébastien Ducruix, Franck Richecoeur, Sébastien Candel |
|---|---|
| Přispěvatelé: | Laboratoire d'Énergétique Moléculaire et Macroscopique, Combustion (EM2C), Université Paris Saclay (COmUE)-Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec |
| Rok vydání: | 2006 |
| Předmět: |
Acoustic Flame Interactions
Materials science business.industry [SPI.FLUID]Engineering Sciences [physics]/Reactive fluid environment Mechanical Engineering Phase (waves) Aerospace Engineering Mechanics Combustion Sweep frequency response analysis Transverse plane Fuel Technology Space and Planetary Science Flame spread Cryogenic Combustion Electronic engineering Combustor Rocket engine Coaxial business |
| Zdroj: | Journal of Propulsion and Power Journal of Propulsion and Power, American Institute of Aeronautics and Astronautics, 2006, 22 (4), pp.790-799. ⟨10.2514/1.18539⟩ |
| ISSN: | 1533-3876 0748-4658 |
| DOI: | 10.2514/1.18539 |
| Popis: | International audience; High-frequency combustion oscillations are investigated experimentally. The combustor fed by cryogenic propellants operates under elevated pressure conditions (pc = 0.9 MPa) and is equipped with three coaxial injectors fed by liquid oxygen and gaseous methane. Injection parameters are in the typical range used in rocket engines. This experiment simulates on a model scale conditions prevailing in such systems, but full similarity is not achieved. The chamber exhibits a set of resonant modes with eigenfrequencies above 1 kHz. The study focuses on high-frequency dynamics resulting from a strong coupling between one of the transverse modes and combustion. The combustor is forced with an external actuator. The eigenmodes are identified with a linear frequency sweep, and then the system is modulated at the first transverse resonant frequency. The flame motion and response are observed with a high speed and two intensified charge-coupled-device cameras recording phase-conditioned images. In a set of experiments carried out on the multiple-injector combustor, operating conditions were changed systematically to determine parameter ranges leading to combustion sensitivity to transverse excitation. Strong coupling is observed in this way with a spectacular modification of the flame spread. Emission from the three flames is notably intensified when this coupling occurs, whereas thermocouples placed on the lateral walls detect a rapid increase in temperature. The OH∗ emission intensity that can be linked to the heat-release rate is increased. A phase analysis indicates that the pressure and OH∗ emission oscillate transversally and in phase at the modulation frequency. This behavior is also observed with the high-speed camera, which also features enhanced reactive vortices convected in the downstream direction at a lower frequency. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|