کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
650690 1457309 2009 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Friction and heat transfer in drag-reducing surfactant solution flow through curved pipes and elbows
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Friction and heat transfer in drag-reducing surfactant solution flow through curved pipes and elbows
چکیده انگلیسی

A study of drag-reducing flow in curved pipes was conducted. In contrast to earlier studies we show that if we use a modified definition of drag reduction that includes only the turbulence effects, we observe indeed the same level of drag reduction in both coiled and straight pipes. More complex results showing reduced drag reduction compared to curved pipes were achieved with elbows. Two elbows of different size and type were tested in turbulent flow of both water and drag-reducing surfactant solution. A more elaborate analysis was conducted for a half-inch threaded elbow with a ratio of curvature radius to diameter of 1.2. The pressure drop and heat transfer were measured in a section downstream from the elbow over a distance of x/D = 130 in order to investigate the hydrodynamic and thermal developments of the flow. The pressure drop coefficient of the elbow was calculated for water and a surfactant solution, based on the total increase in pressure drop in the system due to the presence of the elbow. For a larger welded elbow of 6″ diameter some drag reduction was measured for the surfactant solution.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Mechanics - B/Fluids - Volume 28, Issue 5, September–October 2009, Pages 641–650
نویسندگان
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