کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
654878 885281 2006 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of surface roughness and tube materials on the filmwise condensation heat transfer coefficient at low heat transfer rates
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Effects of surface roughness and tube materials on the filmwise condensation heat transfer coefficient at low heat transfer rates
چکیده انگلیسی

The laminar filmwise condensation heat transfer coefficient on the horizontal tubes of copper and stainless steel was investigated. The outside diameter of the tubes was 15.88 mm, and the tube thickness ranged from 1.07 to 1.6 mm. The polished stainless steel tube had an RMS surface roughness of 0.37 μm, and commercial stainless steel tubes had maximum surface roughness of 15 μm. The tests were conducted at saturation temperatures of 20 and 30 °C, and liquid wall subcoolings from 0.4 to 2.1 °C. The measured condensation heat transfer coefficients were significantly lower than the predicted data by the Nusselt analysis when the ratio of the condensate liquid film thickness to the surface roughness, δ / Rp–v, was relatively low. When the condensate liquid film was very thin, tube material affected the condensation heat transfer coefficient in the filmwise condensation.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Communications in Heat and Mass Transfer - Volume 33, Issue 4, April 2006, Pages 445–450
نویسندگان
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