کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4925548 1431408 2017 15 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Convective heat transfer in supercritical flows of CO2 in tubes with and without flow obstacles
موضوعات مرتبط
مهندسی و علوم پایه مهندسی انرژی مهندسی انرژی و فناوری های برق
پیش نمایش صفحه اول مقاله
Convective heat transfer in supercritical flows of CO2 in tubes with and without flow obstacles
چکیده انگلیسی
Heat transfer measurements to CO2-cooled tubes with and without flow obstacles at supercritical pressures were obtained at the University of Ottawa's supercritical pressure test facility. The effects of obstacle geometry (obstacle pitch, obstacle shape, flow blockage) on the wall temperature and heat transfer coefficient were investigated. Tests were performed for vertical upward flow in a directly heated 8 mm ID tube for a pressure range from 7.69 to 8.36 MPa, a mass flux range from 200 to 1184 kg/m2 s, and a heat flux range from 1 to 175 kW/m2. The results are presented graphically in plots of wall temperature and heat transfer coefficient vs. bulk specific enthalpy of the fluid. The effects of flow parameters and flow obstacle geometry on supercritical heat transfer for both normal and deteriorated heat transfer are discussed. A comparison of the measurements with leading prediction methods for supercritical heat transfer in bare tubes and for spacer effects is also presented. The optimum increase in heat transfer coefficient was found to be for blunt obstacles, having a large flow blockage, and a short obstacle pitch.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Nuclear Engineering and Design - Volume 313, March 2017, Pages 162-176
نویسندگان
, , ,