کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4994576 1458035 2017 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Theoretical and numerical analysis of counter-flow parallel convective exchangers considering axial diffusion
ترجمه فارسی عنوان
تجزیه و تحلیل تئوری و عددی مبدل های کنتراست موازی ضد جریان با توجه به انتشار محوری
کلمات کلیدی
تجزیه گریت عمومی، مبدل های کنترلی، انتقال حرارت و جرم، میکرو مبدل، مبدل های حرارتی فشرده،
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
چکیده انگلیسی
In all cases we found an optimal Péclet number for the cold or hot effectiveness. Even if, as expected, the larger the Péclet the larger the Nusselt number, high transfer performances are found to be poorly efficient and/or to necessitate non-compact elongated exchangers. Performance degradation arising at high Péclet number are found to be related to “convective leaks” taking place within outlets. A fully developed regime occurs at large Péclet and/or for long exchangers, which is fully determined by the first eigenvalue of the generalized Graetz mode decomposition, which is an extension of classical Graetz analysis. Numerical results are found consistent with a generalized linear relation between effectiveness and the number of heat transfer units asymptotically established in the convection dominated regime. This study opens new perspectives for micro-heat exchangers where moderate convection provides the best effectiveness and compactness. This contribution is also useful for giving reference solutions to counter-flow exchangers with realistic inlet/outlet boundary conditions.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 107, April 2017, Pages 154-167
نویسندگان
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