کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
655992 1457651 2011 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Numerical simulation of flow boiling for organic fluid with high saturation temperature in vertical porous coated tube
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Numerical simulation of flow boiling for organic fluid with high saturation temperature in vertical porous coated tube
چکیده انگلیسی

A semi-analytical model is developed for the prediction of flow boiling heat transfer inside vertical porous coated tubes. The model assumes that the forced convection and nucleate boiling coexist together in the annular flow regime. Conservations of mass, momentum, and energy are used to solve for the liquid film thickness and temperature. The heat flux due to nucleate boiling consists of those inside and outside micro-tunnels. To close the equations, a detailed analysis of various forces acting on the bubble is presented to predict its mean departure diameter. The active nucleation site density of porous layer is determined from the pool boiling correlation by introducing suppression factor. The flow boiling heat transfer coefficients of organic fluid (cumene) with high saturation temperature in a vertical flame-spraying porous coated tube are studied numerically. It is shown that the present model can predict most of the experimental values within ±20%. The numerical results also indicate that the nucleate boiling contribution to the overall heat transfer coefficient decreases from 50% to 15% with vapor quality increasing from 0.1 to 0.5.


► A model is developed for the prediction of flow boiling in vertical porous tubes.
► The model assumes that the nucleate boiling plays an important role.
► The present model can predict most of the experimental values within ±20%.
► The results indicate the nucleate boiling contribution decreases from 50% to 15%.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Heat and Fluid Flow - Volume 32, Issue 4, August 2011, Pages 818–825
نویسندگان
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