کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4993910 1458027 2017 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Circumferential distribution of local heat transfer coefficient during steam stratified flow condensation in vacuum horizontal tube
ترجمه فارسی عنوان
توزیع محدوده ضریب انتقال حرارت محلی در جریان تراکم جریان بخار طبقه بندی شده در لوله افقی خلاء
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
چکیده انگلیسی
An experimental system was built up to measure the wetted angle and circumferential distributions of local heat transfer coefficient during the steam stratified flow condensation in vacuum horizontal tube. The wetted angle is mainly affected by vapor quality. It decreases with vapor quality and steam mass flow rate, and increases with the steam saturation temperature. The Biberg's correlation and Rouhani's void fraction correlation are used together to predict the experimental value of wetted angle accurately. The tube wall is divided into filmwise condensation section and liquid accumulation section by the stratified interface. The local heat transfer coefficient in filmwise condensation section is significantly higher than that in liquid accumulation section. The local heat transfer coefficient increases with vapor quality and steam mass flow rate for all locations along the circumferential direction. The increase of temperature difference between steam and cooling water causes the decrease of local heat transfer coefficient in filmwise condensation section and has less effect on that in liquid accumulation section. With the change of steam saturation temperature, the heat transfer coefficients in two sections of the tube appear different variation tendencies. Based on the experimental values, new correlations for local heat transfer coefficient of steam condensation flow in stratified flow pattern are proposed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Mass Transfer - Volume 114, November 2017, Pages 816-825
نویسندگان
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