Abstract
Reflux condensation in steam generator (SG) is one of the major heat removal mechanisms in a loss of residual heat removal (RHR) system event in mid-loop operation during a pressurized water reactor (PWR) plant outage. In order to evaluate the effectiveness of reflux condensation in SG U-tubes, the condensation heat transfer characteristics in the presence of a non-condensable gas must be clarified. Local temperature data were previously measured for steam-air mixtures under gas-liquid countercurrent flow, in a vertical tube of inner diameter 19.3 mm. In this study, local reflux heat transfer coefficients were calculated by evaluating steam flow rate profile along the tube at low heat fluxes assuming saturated steam conditions and empirical correlations were derived. The correlations are valid over a range 2–9,000W/m2-K for 0.1–0.4MPa, 0.014–0.2 air mass fraction. The axial distributions of the steam—air mixture temperatures calculated using the correlation agreed well with the measured results and validity of evaluation methods and the correlation were verified.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
