کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
658487 1458086 2013 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Influences of vertical and horizontal pitches on the natural convection of two staggered cylinders
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Influences of vertical and horizontal pitches on the natural convection of two staggered cylinders
چکیده انگلیسی

Natural convection heat transfer phenomena for two vertically staggered cylinders were investigated experimentally and numerically for both laminar and turbulent flows. Experiments were performed for the Rayleigh numbers 1.5 × 108 and 2.5 × 1010 and the Prandtl number 2014, varying the vertical and horizontal pitch-to-diameter ratios using a copper electroplating system. Numerical studies were carried out to investigate the effect of the Prandtl number. The heat transfer rates of the lower cylinders were in close agreement with those of single cylinders. However, the heat transfer rates of the upper cylinders were influenced by the plumes from the lower cylinders, exhibiting preheating, velocity, and side-flow effects. At a very small pitch, the preheating effect was dominant, whereas at a larger pitch, the velocity effect became dominant. Both effects weakened with increasing horizontal pitch-to-diameter ratio. Under turbulent flow conditions, it was visually and experimentally confirmed that laminarization occurs on the top part of the upper cylinder, due to buoyancy-aided mixed convective turbulent flow.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 57, Issue 1, 15 January 2013, Pages 1–8
نویسندگان
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