کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10264806 458028 2017 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Flow field measurements of a series of turbulent premixed and stratified methane/air flames
ترجمه فارسی عنوان
اندازه گیری میدان جریان از یک سری از متان / هوا شعله ور شده با متخلخل و طبقه بندی شده آشفته
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی
This paper presents flow field measurements for the turbulent stratified burner introduced in two previous publications in which high resolution scalar measurements were made by Sweeney et al. [1], [2] for model validation. The flow fields of the series of premixed and stratified methane/air flames are investigated under turbulent, globally lean conditions (ϕg = 0.75). Velocity data acquired with laser Doppler anemometry (LDA) and particle image velocimetry (PIV) are presented and discussed. Pairwise 2-component LDA measurements provide profiles of axial velocity, radial velocity, tangential velocity and corresponding fluctuating velocities. The LDA measurements of axial and tangential velocities enable the swirl number to be evaluated and the degree of swirl characterized. Power spectral density and autocorrelation functions derived from the LDA data acquired at 10 kHz are optimized to calculate the integral time scales. Flow patterns are obtained using a 2-component PIV system operated at 7 Hz. Velocity profiles and spatial correlations derived from the PIV and LDA measurements are shown to be in very good agreement, thus offering 3D mapping of the velocities. A strong correlation was observed between the shape of the recirculation zones above the central bluff body and the effects of heat release, stoichiometry and swirl. Detailed analyses of the LDA data further demonstrate that the flow behavior changes significantly with the levels of swirl and stratification, which combines the contributions of dilatation, recirculation and swirl. Key turbulence parameters are derived from the total velocity components, combining axial, radial and tangential velocities.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Combustion and Flame - Volume 160, Issue 10, October 2013, Pages 2017-2028
نویسندگان
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