کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
169597 458022 2010 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of radiation and compression on propagating spherical flames of methane/air mixtures near the lean flammability limit
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
Effects of radiation and compression on propagating spherical flames of methane/air mixtures near the lean flammability limit
چکیده انگلیسی

Large discrepancies between the laminar flame speeds and Markstein lengths measured in experiments and those predicted by simulations for ultra-lean methane/air mixtures bring a great concern for kinetic mechanism validation. In order to quantitatively explain these discrepancies, a computational study is performed for propagating spherical flames of lean methane/air mixtures in different spherical chambers using different radiation models. The emphasis is focused on the effects of radiation and compression. It is found that the spherical flame propagation speed is greatly reduced by the coupling between thermal effect (change of flame temperature or unburned gas temperature) and flow effect (inward flow of burned gas) induced by radiation and/or compression. As a result, for methane/air mixtures near the lean flammability limit, the radiation and compression cause large amounts of under-prediction of the laminar flame speeds and Markstein lengths extracted from propagating spherical flames. Since radiation and compression both exist in the experiments on ultra-lean methane/air mixtures reported in the literature, the measured laminar flame speeds and Markstein lengths are much lower than results from simulation and thus cannot be used for kinetic mechanism validation.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Combustion and Flame - Volume 157, Issue 12, December 2010, Pages 2267–2276
نویسندگان
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