کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
658945 1458099 2012 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of surface free energy difference on steam-ethanol mixture condensation heat transfer
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Effect of surface free energy difference on steam-ethanol mixture condensation heat transfer
چکیده انگلیسی

The condensation heat transfer of steam-ethanol mixture with different weight fractions was investigated experimentally at atmospheric pressure. The results indicate that the heat transfer coefficients (HTC) and condensation modes, i.e. filmwise condensation (FWC), transition state and dropwise condensation (DWC), varied with the mixture compositions and the vapor-surface temperature differences. The interface effect, in terms of equivalent surface free energy difference between condensate and ultra thin liquid film, was introduced to analyze the variation of condensation modes and heat transfer coefficient. The equivalent surface free energy differences under various vapor conditions and vapor-surface temperature differences are calculated quantitatively. The experimental results show that as equivalent surface free energy difference was gradually increased, the condensation mode alternates from filmwise to transition state and finally to dropwise condensation, with heat transfer coefficient simultaneously increasing. The effect of surface free energy difference was also introduced to analyze the data in literature, and the effect of subcooling on heat transfer coefficient was discussed from the perspective of interface effect. The results show that as the vapor-surface temperature difference was gradually increased, the surface free energy difference increase accordingly and then reaches its peak value. The heat transfer coefficient exhibits the same tendency as equivalent surface free energy.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 55, Issue 4, 31 January 2012, Pages 531–537
نویسندگان
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