کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
205302 461103 2016 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of geometrical contraction on vortex breakdown of swirling turbulent flow in a model combustor
ترجمه فارسی عنوان
اثر انقباض هندسی بر روی شکست گردابی جریان متلاطم در یک سوختگی مدل
کلمات کلیدی
جریان چرخش شکستگی گرداب، مشعل توربین گاز، انقباض خروجی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی

Large Eddy Simulation (LES) studies of isothermal and incompressible turbulent swirling flows in a model gas turbine combustion chamber geometry have been carried out. The focus is on the effect of outlet geometry contraction on the vortex breakdown structure and the precessing vortex core in the chamber. Nine different outlet geometries with different contraction ratio Cr are considered. The results from a baseline case are compared with experimental data in the literature. The swirling flow is generated using a swirler with fifteen guide vanes similar to an existing industrial gas turbine burner. In all cases the swirler and the main chamber geometry are kept the same. The detailed swirler geometry is considered in the simulation using unstructured grids. Sensitivity tests on the influence of the grid resolution and the subgrid scale models are carried out. The mean flow field shows different vortex breakdown structures when the contraction ratio changes from 0.325 to 1.0. In particular, along the axis of the chamber the flow is shown to switch its direction when the contraction increases as a result of the change of the structure of the center recirculation zone. The underlying flow physics is analyzed by comparing the budget terms in the momentum equations, and by performing a global instability analysis.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Fuel - Volume 170, 15 April 2016, Pages 210–225
نویسندگان
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