کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
667514 1458575 2008 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Multi-channel effect of condensation flow in a micro triple-channel condenser
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Multi-channel effect of condensation flow in a micro triple-channel condenser
چکیده انگلیسی

Multi-channel effect is important to understand transport phenomenon in phase change systems with parallel channels. In this paper, visualization studies were performed to study the multi-channel effect in a silicon triple-channel condenser with an aspect ratio of 0.04. Saturated water vapor was pumped into the microcondenser, which was horizontally positioned. The condenser was cooled by the air natural convention heat transfer in the air environment. Flow patterns are either the annular flow at high inlet vapor pressures, or a quasi-stable elongated bubble at the microchannel upstream followed by a detaching or detached miniature bubble at smaller inlet vapor pressures. The downstream miniature bubble was detached from the elongated bubble tip induced by the maximum Weber number there.It is observed that either a single vapor thread or dual vapor threads are at the front of the elongated bubble. A miniature bubble is fully formed by breaking up the vapor thread or threads. The transient vapor thread formation and breakup process is exactly symmetry against the centerline of the center channel. In side channels, the Marangoni effect induced by the small temperature variation over the channel width direction causes the vapor thread formation and breakup process deviating from the side channel centerline and approaching the center channel. The Marangoni effect further forces the detached bubble to rotate and approach the center channel, because the center channel always has higher temperatures, indicating the multi-channel effect.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Multiphase Flow - Volume 34, Issue 12, December 2008, Pages 1175–1184
نویسندگان
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