کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10148981 1646708 2018 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Numerical study of heat transfer on using lobed cross sections in helical coil heat exchangers: Effect of physical and geometrical parameters
ترجمه فارسی عنوان
بررسی عددی انتقال حرارت در استفاده از مقاطع عرضی در مبدل های حرارتی کویل هلی کویل: اثر پارامترهای جسمی و هندسی
کلمات کلیدی
انتقال گرما، افت فشار، کویل حلقه ای، مقطع لوبدار نانو سیال،
موضوعات مرتبط
مهندسی و علوم پایه مهندسی انرژی انرژی (عمومی)
چکیده انگلیسی
In this paper, flow characteristics and heat transfer applications of a helical coil with four different lobed cross sections are investigated numerically. The flow is laminar, Reynolds number changes from 1300 to 2500 and the wall of the helical coil in all the simulations has a constant temperature of 373 K. Effects of cross section lobe number (n) on heat transfer rate and pressure drop are studied. The results show that a coil with n = 6 presents the highest Nusselt number (Nu) and the lowest friction factor coefficient (f). In the next step, effects of different geometrical parameters (coil pitch, height, and diameter) and different fluids (Prandtl number) are studied. It is observed that the coil diameter has the greatest effect in comparison to the other geometrical parameters. Last but not the least, the effect of adding Al2O3 nanoparticles to water is discussed. It can be observed that upon using Al2O3-Water nanofluid, the Nusselt number increased 28 percent compared to water as the working fluid. But, it is seen that the friction factor coefficient does not change considerably. Moreover, it can be seen that the higher volume concentrations result in higher heat transfer rates. Finally, a correlation based on the numerical data for predicting Nusselt number is presented.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Energy Conversion and Management - Volume 176, 15 November 2018, Pages 236-245
نویسندگان
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