Predicting chemical flame lengths and lift-off heights in enclosed, oxy-methane diffusion flames at varying O2/CO2 oxidizer dilution ratios

• Autorzy: Krishnamoorthy G. , Ditaranto M.
• Języki publikacji: EN

Abstrakty

EN

Experiments have shown reactor confinement, wall temperatures and radiative transfer to influence the flame length and lift-off characteristics of oxy-methane flames. In this study, the performances of the Shear Stress Transport (SST) k-ω turbulence model, a skeletal methane combustion mechanism (16 species and 41 reactions) and two weighted sum of gray gas models (WSGGM) towards capturing these flame characteristics are evaluated against measurements obtained from oxy-methane flames across a wide range of oxidizer O2/CO2 ratios and fuel Reynolds numbers. Gas composition, gas and wall temperatures, flame length measurements and inferences of lift-off heights from OH* chemiluminescence imaging are employed in the assessment. The corresponding numerical estimate of flame length and lift-off heights were made by determining the flame shape by the locus of points at which the CO concentrations reduce to 1% of their peak values within the flame. The predicted gas temperatures and compositions compared reasonably well against measurements. The criterion for defining the flame shape based on CO concentrations appears promising since the trends in chemical flame length and lift-off height predictions agreed reasonably well with the measurements across the range of oxidizer concentrations and fuel Reynolds numbers. Flame length prediction sensitivities to the wall temperatures and the WSGGM model were also assessed.

Słowa kluczowe

EN

oxy-methane; combustion model; flame length; lift-off height; WSGGM

PL

oxy-metan; model spalania; długość płomienia; wysokość podnoszenia; WSGGM

• Wydawca: Institute of Heat Engineering, Warsaw University of Technology
• Czasopismo: Journal of Power Technologies
• Rocznik: 2017
• Tom: Vol. 97, nr 4
• Strony: 370--377
• Opis fizyczny: Bibliogr. 29. poz., rys., tab., wykr.

Twórcy

autor

Krishnamoorthy G.

• Department of Chemical Engineering, Harrington Hall Room 323, 241 Centennial Drive, University of North Dakota, Grand Forks, ND 58202-7101, USA

autor

Ditaranto M.

• SINTEF Energy Research, 7465 Trondheim, Norway

Bibliografia

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Uwagi

PL

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).