کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
646791 1457164 2013 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of unstable flame structure and recirculation zones in a swirl-stabilized dump combustor
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Effects of unstable flame structure and recirculation zones in a swirl-stabilized dump combustor
چکیده انگلیسی
There has been increased demand in recent years for low NOx gas turbines to meet stringent emission goals by operating in a lean, premixed combustion mode. Unfortunately, detrimental combustion instabilities are often excited within the combustor when it operates under lean conditions, degrading performance and reducing combustor life. To eliminate the onset of these instabilities and develop effective approaches for their control, the mechanisms responsible for their occurrence must be understood. This study addresses structural characteristics of natural gas flames in a lean premixed swirl-stabilized combustor with attention focused on the effect of the formation of recirculation zones and vortex interaction on the combustion instability. To improve our understanding of the role of the recirculation zone and vortex combustion instability, the flame structure was investigated for various mixture velocities, equivalence ratios and swirl numbers. The optically accessible combustor allowed for the laser diagnostics of particle image velocimetry (PIV) measurement, while OH chemiluminescence was used to characterize the flow structure under both cold flow conditions and hot flow combustion conditions. Dynamic pressures were also measured at the same time to investigate characteristics of the combustion phenomenon. We also observed fundamental longitudinal type of combustion instability characteristics related to the instability of thermo-acoustics. The result suggests that the formation of the recirculation zone is strongly related to the occurrence of combustion instabilities.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Thermal Engineering - Volume 58, Issues 1–2, September 2013, Pages 125-135
نویسندگان
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