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Портал Begell Электронная Бибилиотека e-Книги Журналы Справочники и Сборники статей Коллекции
International Journal of Energetic Materials and Chemical Propulsion
ESCI SJR: 0.149 SNIP: 0.16 CiteScore™: 0.29

ISSN Печать: 2150-766X
ISSN Онлайн: 2150-7678

International Journal of Energetic Materials and Chemical Propulsion

DOI: 10.1615/IntJEnergeticMaterialsChemProp.2013005758
pages 487-510

A COMPUTATIONAL STUDY OF A DUAL-MODE RAMJET COMBUSTOR WITH A CAVITY FLAMEHOLDER

Christer Fureby
Defence Security Systems Technology The Swedish Defence Research Agency (FOI) SE 147 25 Tumba, Stockholm, Sweden
J. Tegner
The Swedish Defense Research Agency − FOI, SE 147 25, Tumba, Stockholm, Sweden
R. Farinaccio
Defence R&D Canada − Valcartier, Quebec City, QC, G3J1X5, Canada
Robert Stowe
Defence Research and Development Canada, Quebec City, Quebec, Canada, G3J1X5
D. Alexander
Martec, Limited, 1888 Brunswick St., Suite 400, Halifax, NS, B3J 3J8, Canada

Краткое описание

In this study we use Reynolds-averaged Navier−Stokes (RANS) and large-eddy simulation (LES) combustion models to analyze the flow, fuel injection, mixing, self-ignition, and combustion in a dual-mode ramjet combustor with a cavity flameholder. Comparison with experimental data is used to evaluate the predictive capabilities of the models and to provide additional information about the combustion physics in the dual-mode ramjet combustor. Both the experimental data and the LES results predict two distinct behaviors depending on the value of the stagnation temperature, T0; for To < 1150 K, the flame anchors in the shear layer shedding off the leading edge of the cavity (cavity-stabilized combustion), whereas for T0 > 1350 K the flame anchors just downstream of fuel injection in the jet wake due to heat release at the lower combustor wall (jet-wake-stabilized combustion). For intermediate values, 1150 < T0 < 1350, the flame oscillates between cavity-stabilized and jet-wake-stabilized combustion. The oscillating mode is more difficult to compute simply because the oscillations have a frequency between 20 and 95 Hz, hence requiring long simulation times. Unfortunately, the RANS computations are not successful in capturing the different modes of operation. This deficiency is believed to be caused by the failure to capture the interactions between the flow and the chemical kinetics.