Turbulent flame-wall interactions for flames diluted by hot combustion products

Abstract This paper presents measurements of 10 kHz OH planar laser induced fluorescence (PLIF) with an objective to study the interaction of effusion cooling with the flame and hot combustion products in the liquid fueled combustor. The combustor rig is a single sector representation a rich-burn/quick-quench/lean-burn (RQL) configuration. It consists of a swirl nozzle, dilution, and effusion jets. The rig is operated under realistic aircraft conditions, including elevated combustor inlet temperature, and elevated pressure. The PLIF laser sheet was arranged perpendicular and parallel to the liner at distinct liner locations. Parametric variations of important parameters, namely equivalence ratio, and effusion cooling air blowing ratio are conducted to investigate their effect on flame-effusion jet interactions. The PLIF images were analyzed using several data reduction techniques to de-noise the images and identify patterns in the effusion jet-flame interactions. Results show that the effusion jets are highly unsteady, interacting strongly with the turbulent flame from the swirl nozzle and the dilution jets. This work is an extension of recent effusion film mixing studies that were performed with acetone PLIF under non-reacting conditions.

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Studies on the Characteristics of Three-Inline Non-Premixed Turbulent Oxy-Methane Flame Jets

Volume 2: Combustion, Fuels, and Emissions; Renewable Energy: Solar and Wind; Inlets and Exhausts; Emerging Technologies: Hybrid Electric Propulsion and Alternate Power Generation; GT Operation and Maintenance; Materials and Manufacturing (Including Coatings, Composites, CMCs, Additive Manufacturing); Analytics and Digital Solutions for Gas Turbines/Rotating Machinery ◽

10.1115/gtindia2019-2410 ◽

2019 ◽

Author(s):

Tamal Jana ◽

Mrinal Kaushik

Keyword(s):

Velocity Distribution ◽

Equivalence Ratio ◽

Turbulent Flame ◽

Combustion Products ◽

Far Field ◽

Streamwise Direction ◽

Single Jet ◽

Methane Flame ◽

Lift Off ◽

Surrounding Fluid

Abstract In the present study, the characteristics of three-inline non-premixed Oxy-Methane turbulent flame jets, with Methane jet at the center and two Oxygen jets on either side, are computationally investigated. For all the jets, the velocity is varied from 10.13 m/s to 108 m/s. It is found that, in the presence of central jet, the mixing of lateral jets are delayed further downstream. In contrast, the central jet diffuses at a faster rate. At far-field locations, all the jets merge with each other and form a single jet, which can be seen from the uniformity of the radial velocity distribution. The turbulent intensity is found to be more at the jet periphery, where jets interact with the surrounding fluid. The temperature of the flame is found to be higher at the periphery of the methane and the oxygen jets, due to the existence of most appropriate equivalence ratio. Also, the flame lift-off height is found to be increasing with the jet velocity. The concentration of methane is reduced along the streamwise direction due to the penetration of combustion products towards the jet centerline.

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New Universal Quartz Burner for Decomposition of Samples by the Wickbold Combustion Technique in Determination of Arsenic, Antimony, Selenium, Mercury, and Lead

Journal of AOAC International ◽

10.1093/jaoac/80.5.1084 ◽

1997 ◽

Vol 80 (5) ◽

pp. 1084-1090 ◽

Cited By ~ 1

Author(s):

Dietmar Erber ◽

Karl Cammann ◽

JüRgen Roth

Keyword(s):

Statistical Tests ◽

Turbulent Flame ◽

Hydride Generation ◽

Absorption Spectrometry ◽

Combustion Products ◽

Volatile Elements ◽

Nitrogen Stream ◽

Combustion Technique ◽

Oxyhydrogen Flame

Abstract A new universal quartz burner for the Wickbold decomposition method is investigated with respect to its fast and efficient decomposition of solid samples for determining volatile trace elements like arsenic, antimony, selenium, mercury, and lead. Decomposition is based on burning samples in an oxyhydrogen flame. The samples are transported into the flame in gaseous form by pyrolyzing the material in an oven heated to 1100C. During this decomposition step, a nitrogen stream loaded with carbon tetrachloride mobilizes the volatile elements, causing separation from the sample matrix. An effective precombustion in oxygen and a large turbulent flame improve decomposition conditions. Different certified inorganic and organic reference materials are pyrolyzed and combusted, and the combustion products are absorbed in water. Metals found in the absorption solutions are analyzed by flow injection/hydride generation/atomic absorption spectrometry. Data were analyzed by several statistical tests recommended for quality control purposes. The combination of a decomposition and detection method resulted in very low detection limits: 1.4 μg arsenic/kg, 0.8 pig antimony/kg, 1.8 μg mercury/kg, 1.4 μg lead/kg, and 1.6 μg selenium/ g can be detected without an extra enrichment step.

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