کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
660459 1458116 2010 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A numerical study of algebraic flux models for heat and mass transport simulation in complex flows
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
A numerical study of algebraic flux models for heat and mass transport simulation in complex flows
چکیده انگلیسی

A numerical study of heat and mass transport based on the Reynolds-Averaged Navier–Stokes and scalar transport equations is presented to establish the predictive capabilities of algebraic flux models compared to the standard eddy-diffusivity representation. The analysis of scalar transport in simple-shear flows is initially performed to provide a basic validation of numerical techniques and scalar flux closures. The evaluation of algebraic models is carried out by examining the flow and scalar transport phenomena over a wavy wall and comparing the results to reliable direct numerical simulations. Despite the similarities with the standard gradient-diffusion hypothesis and the questionable validity of local-equilibrium conditions, the results show that algebraic models provide an efficient way to improve heat and mass transport predictions in complex flows with respect to the standard eddy-diffusivity model. The impact of abandoning the isotropic eddy-diffusivity in favor of a tensorial representation is found particularly significant in the analysis of scalar dispersion from a point source over the wavy wall, where lateral transport comes into play. While it is found that algebraic closures also represent a reasonable approximation for the spanwise scalar flux, the lateral spread of scalar concentration is considerably under-estimated by the standard gradient-diffusion model.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 53, Issues 21–22, October 2010, Pages 4511–4524
نویسندگان
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