کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6468462 1423561 2017 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Experimental and numerical characterization of freely propagating ozone-activated dimethyl ether cool flames
ترجمه فارسی عنوان
خصوصیات آزمایشی و عددی آزاد سازی شعله های سرد دیمیتریل اتئین فعال آزاد شده ازن
کلمات کلیدی
شعله های سرد. آزادانه تبلیغ؛ شعله آرام؛ اکسیداسیون در دمای پایین. ضریب دمایی منفی؛ دی متیل اتر
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی

Experimental flame characterization is necessary for the development and validation of chemical kinetics models. Low temperature oxidation produces a cool flame, which is a combustion phenomenon resulting from negative temperature coefficient (NTC) behavior. Kinematic stabilization of premixed, freely propagating, ozone-activated, cool flames of dimethyl ether (DME) has been investigated at sub-atmospheric pressure of 7.3 kPa using a laminar flat flame Hencken burner. This platform permits estimation of laminar propagation speed, as well as spatially-resolved temperature and species mole fractions along the burner axis. Stability mapping for a range of equivalence ratios (ϕ) was performed to determine the range of ozone concentrations for which a cool flame can be sustained. Based on the results of stability mapping, an ozone concentration of 6.1% in oxygen was chosen to investigate the characteristics of DME cool flames over a range of equivalence ratios from ϕ = 0.4 to 1.4. Two distinct cool flame stabilization modes were observed in experiments: a burner-stabilized mode at low reactant flow rates, and a freely propagating mode at higher flow rates. From the transition between the two modes, cool flame propagation speeds from ϕ = 0.4 to 1.4 were determined. Flame temperatures were measured at these equivalence ratios, with maximum temperatures decreasing from 885 K at ϕ = 0.4 to 779 K at ϕ = 1.4. A single equivalence ratio of ϕ = 0.6 was chosen for detailed investigation of the flame structure, including spatial measurements of temperature and species as a function of height above the burner. Experimental results were compared to numerical simulations of a ϕ = 0.6 cool flame. Experimental propagation speed was found to be within 25% of the numerical value, and significant agreement between experimental and numerical species profiles was observed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Combustion and Flame - Volume 176, February 2017, Pages 326-333
نویسندگان
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