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Download or read book Flow Dynamics and Condensation of Film Flows in Small Modular Reactors written by Dongyoung Lee and published by . This book was released on 2015 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is renewed interest in the reliability and safety of nuclear power plants following the Fukushima Daiichi nuclear accident followed by 8.9 magnitude earthquake and Tsunami with the height of 15 m on March 11, 2011. Small Modular Reactors (SMRs) have been developed to improve safety systems by utilizing passive and natural circulation forces under normal operations and accident conditions. One key feature of the safety systems in SMRs is the use of containment condensation to prevent core melt down. For further development of the SMR for design certifications, the condensation model at relatively high pressures compared with current operating power plants should be verified and validated. For this process, at Oregon State University, the MASLWR (Multi Application Small Light Water Reactor) test facility, which has 1:3 length scale, can perform integrated tests on containment condensation of SMRs. Using the MASLWR test facility experimental data, this study investigated three major subjects: heat flux estimation on the containment wall, flow transition of condensation film flow dynamics and assessing the scaling effects of the MASLWR test facility. An inverse heat conduction algorithm was developed to estimate the heat fluxes of film condensation at the containment wall in the MASLWR test facility during transients. Through a fundamental one-dimensional approach for condensation film flow, the governing equations were derived and numerically solved. A linear perturbation stability analysis using steady-state results of condensation film flow at the containment wall found that Re ~1600 is the transition point between laminar and turbulent film flow regimes. This finding agreed with the experimental results of Ishigai et al. (1974) and Morioka et al. (1993). Based on scaling analysis using the diffusion layer model and experimental correlations, the length distortion factor was examined. In this study, it was found that the 1:3 length scale test facility underestimated the heat transfer rate more than the prototype. The results presented in this dissertation cover the film flow dynamics of condensation film flows as well as an inverse heat transfer calculation to advance the knowledge of containment condensation in SMRs.