کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7056030 1458048 2016 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Direct contact condensation of steam jet in crossflow of water in a vertical pipe. Experimental investigation on condensation regime diagram and jet penetration length
ترجمه فارسی عنوان
تراکم تماس مستقیم جت بخار در جریان متقاطع آب در یک لوله عمودی. بررسی تجربی روی نمودار ریزش تراکم و طول نفوذ جت
کلمات کلیدی
تراکم تماس مستقیم جت بخار، جریان عبور نمودار رژیم چگالی طول نفوذ جت،
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
چکیده انگلیسی
The direct contact condensation of jets in fluid has been of great importance in many industrial applications. Experiments on condensing jets in initially stagnant fluid in pool have increased significantly in sophistication over the last few decades. For condensing jets in crossflow, however, the flow and geometry characteristics of the jet might be fundamentally different due to the complex convection effect induced by the crossflow. Here, experiments are performed to investigate direct contact condensation of steam jet in crossflow of water in a vertical pipe. The condensation regime diagram and jet penetration length are investigated visually by using high-speed camera and image processing methods. The condensation regime diagram mainly contains three kinds of condensation regime, i.e., chugging, condensation oscillation and stable condensation (i.e., stable conical shape, stable cylinder shape and stable expansion shape). The condensation regime is not only affected by steam mass flux and water temperature, but also affected significantly by Reynolds number of water flow. Therefore, condensation regime diagrams for different Reynolds number of water flow are developed. Both the regions of the chugging and condensation oscillation regimes expand slightly towards higher steam mass flux as Reynolds number of water flow increases. The dimensionless jet penetration length from experimental results is found to be in the range of 0.78-6.84. It increases with increase of steam mass flux and water temperature, but decreases with increase of Reynolds number of water flow. Empirical correlation is proposed for predicting the dimensionless jet penetration length depending on three dimensionless parameters, i.e., dimensionless steam mass flux, condensation driving potential and Reynolds number of water flow. The predicted results agree well with experiments and the discrepancies are within ±20%.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 94, March 2016, Pages 528-538
نویسندگان
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