کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4987307 | 1455150 | 2017 | 50 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Bubbles' slip velocity reduction in the near wall region of turbulent bubbly pipe flows under different gravity conditions
ترجمه فارسی عنوان
کاهش سرعت لغزش حباب در ناحیه دیوار نزدیک جریان لوله ای شیب دار تحت شرایط مختلف گرانش
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
آشفتگی، جریان حباب، سرعت نسبی، دو مدل مایع، انتقال بین فاز، توزیع فاز،
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
تصفیه و جداسازی
چکیده انگلیسی
Bubbles' dynamics in the near-wall region of turbulent bubbly flows can significantly influence transfer mechanisms. The present paper is devoted to an analysis of the interfacial momentum transfer in the turbulent bubbly pipe flows under different gravity conditions, in particular in the near-wall region where the void fraction and turbulent shear stress gradients are important. A complete formulation of the turbulent contribution of the added mass force is proposed and applied to axisymmetric parallel bubbly flows. The resulting closure is analyzed using the vertical pipe bubbly flows experimental data carried out by Colin et al. (2012) under different gravity conditions, upward flow (1Â g), downward flow (â1Â g) and bubbly flow under microgravity condition (0Â g). Sensitive analysis of the momentum transfer closure show that in the near-wall region of upward and downward bubbly flows, the turbulent contributions of the added mass force may become large enough to oppose the gravity action and to produce significant reduction of the bubbles' slip velocities as observed in experiments. In micro-gravity conditions, the turbulent contributions of the added force are of the same order of magnitude than the residual gravity.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemical Engineering Research and Design - Volume 119, March 2017, Pages 231-244
Journal: Chemical Engineering Research and Design - Volume 119, March 2017, Pages 231-244
نویسندگان
Jamel Chahed, Ghazi Bellakhel, Hatem Kanfoudi,