کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8065657 1520694 2015 12 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Investigation of flow structure around a horizontal cylinder at different elevations in shallow water
ترجمه فارسی عنوان
بررسی ساختار جریان در اطراف سیلندر افقی در ارتفاعات مختلف در آب کم عمق
کلمات کلیدی
سیلندر افقی جریان در اطراف خط لوله، سرعت سنجی تصاویر ذرات، جداسازی،
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی دریا (اقیانوس)
چکیده انگلیسی
Flow characteristics around a horizontal circular cylinder were investigated in shallow water. The diameter of circular cylinder, the height of shallow water and free stream velocity were kept constant during the experiments as D=30 mm, hw=60 mm and U=167 mm/s, respectively. Particle Image Velocimetry (PIV) was used to measure instantaneous and time-averaged velocity vector fields in the near wake region. In order to investigate the effect of immersion, the cylinder was placed at eight different elevations (hD) between bottom and free surface (from 7.5 to 60 mm with 7.5 mm increments). Instantaneous and time-averaged velocity vector field, corresponding streamline patterns and Reynolds stress correlation were used to analyze the behavior of the flow downstream of horizontal cylinder. The mean velocity vector field, corresponding streamline topology and Reynolds stress correlation were obtained using 500 instantaneous images. As the immersion level ratio (hD/D) increases, the magnitude of jet-like flow velocity goes up ranged from hD/D=0.25-1. Time averaged flow characteristics show that there is a difference between primary and developing circulation bubble depending on direction of rotation. This occurrence causes the entrainment and this stimulates the momentum transfer between the core and wake flow region for hD/D=1 and 2 cases.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ocean Engineering - Volume 96, 1 March 2015, Pages 56-67
نویسندگان
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