کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
170069 458072 2008 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The porous-plug burner: Flame stabilization, onset of oscillation, and restabilization
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
پیش نمایش صفحه اول مقاله
The porous-plug burner: Flame stabilization, onset of oscillation, and restabilization
چکیده انگلیسی

In recent studies of edge-flames it was found that when the characteristic gas velocity exceeds a critical value the flame often undergoes spontaneous oscillations. The oscillations are amplified as the flow rate increases, reaching a maximum amplitude, and then decrease with further increasing flow rate until the flame restabilizes. In this paper we examine the concept of flame restabilization in a simpler but related problem—the planar premixed flame on a porous-plug burner—which is amenable to a full stability analysis. We show the dependence of all possible steady states on the relevant parameters, including the mass flow rate, the effective Lewis number of the mixture, the overall activation energy of the chemical reaction, and the extent of heat release. A linear stability analysis is then carried out to examine whether these steady states are stable to small disturbances. The analysis determines the critical conditions for the onset of instability, as well as the nature of the instability. In particular, we show that by decreasing the mass flow rate, the flame, which is at first stable, starts to oscillate back and forth for a limited range of gas velocities but is then restabilized by further decreasing the mass flow rate. We also show that the properties of the plug, such as the thickness of the plate and its porosity, play a significant role in flame stabilization.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Combustion and Flame - Volume 153, Issues 1–2, April 2008, Pages 105–118
نویسندگان
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