کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
586043 1453267 2016 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Experimental and LES investigation of premixed methane/air flame propagating in a chamber for three obstacle BR configurations
ترجمه فارسی عنوان
بررسی تجربی و LES انتشار شعله متان/هوا از پیش مخلوط در یک اتاقک برای تنظیمات BR سه مانعی
کلمات کلیدی
نسبت انسداد؛ مکانیسم شعله گرداب؛ LES؛ FSD؛ شعله طوماری؛ منطقه چرخش کوچک
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بهداشت و امنیت شیمی
چکیده انگلیسی


• A recirculation zone above the obstacle is discovered during methane/air flame propagation in an obstructed chamber.
• The flame deceleration by the flame-vortex interaction for three obstacle BR configurations is observed.
• The regimes of flame-vortex interaction are explored by the Karlovitz number.

The paper aims at revealing the effect of blockage ratio (BR) on the flame acceleration process and the flame-vortex mechanism in an obstructed chamber based essentially on the experimental and numerical methods. In the experiments, high-speed video photography and pressure transducer are used to study the flame shape changes and pressure dynamics. In the numerical simulations, large eddy simulation (LES) with the flame surface density (FSD) model is applied to investigate the interaction between the moving flame and vortices induced by obstacle. The results demonstrate that the flame propagation process can be divided into four stages, namely spherical flame, finger-shaped flame, jet flame and volute flame for three obstacle BR configurations, and a small recirculation zone is observed above the obstacle only for BR = 0.5. The peak of flame tip speed and pressure growth rate increases with the blockage ratio. The generation and evolution of the vortex behind the obstacle can be attributed to the initial flame acceleration, while the subsequent flame deceleration is due to the flame-vortex interaction. In addition, the transition from a “thin reaction zones” to a “broken reaction zones” is also observed in the simulation.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Loss Prevention in the Process Industries - Volume 41, May 2016, Pages 48–54
نویسندگان
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