کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7054966 1458040 2016 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
High Rayleigh number convection in a cubic cell with adiabatic sidewalls
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
High Rayleigh number convection in a cubic cell with adiabatic sidewalls
چکیده انگلیسی
Turbulent Rayleigh-Bénard convection in cubic cells is studied experimentally using two similar but not identical experimental setups in different laboratories. Both teams have made experiments for the same set of Prandtl and Rayleigh numbers (Pr = 3.5, Pr = 6.1, Ra=2.0·109, Ra=6.0·109, Ra=1.6·1010). Experiments showed that the structure of the mean flow and local characteristics of turbulent pulsations are robust and do not depend strongly on the technical details of experimental setup. Periodic low-frequency oscillations and orientations of large-scale circulation (LSC) are more sensitive to the experimental setup design. Long-time measurements using differential thermocouples revealed that preferential orientation of LSC is along of one of the diagonals, however it can deviate from exact diagonal orientation. Analyses of temperature and velocity measurements showed that dominant periodic oscillations of LSC can not be explained as simple modulation of the intensity of the large-scale diagonal flow because most intense oscillations are observed in the direction, which is orthogonal to the plane of LSC. Experimental data obtained independently by two teams can be used as a benchmark for CFD codes. Numerical simulation using a standard widely-spread CFD code was carried out. In general, on the base of overall comparison between experimental and large-eddy simulation results we concluded that for the described regimes LES gives satisfactory agreement with experiment reproducing the small-scale dynamics of the turbulent flow and the behavior of LSC.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 102, November 2016, Pages 201-212
نویسندگان
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