Abstract
The concerns on nuclear safety and security have been increased tremendously after the Fukushima Daiichi nuclear disaster on 11 March 2011 in Japan. Issues on the control of hydrogen concentration and the efficient cooling of spent fuel pools after water implementation are the most essential concerns in recent years. This study conducts the thermal hydraulic analysis for the spent fuel pool referred the designs of Maanshan nuclear power plant in Taiwan. Natural circulation and the cross flow inside the fuel bundle are the major features inside the spent pool and need to be investigated by an appropriate model. In the previous investigations, the application of porous models had been employed in numerical computations for spent fuel pool due to the limitations of simulation resources. Thus, only part of the physics and thermo-hydraulic information had been obtained by the simplified model. This study aims to provide the detailed phenomena of flow fluid field and temperature field as well as the heat transfer coefficients in normal or abnormal conditions. The numerical computations are conducted by commercial CFD code STAR-CCM+ with 8 CPUs and 96 GB memories. The abnormal conditions include the transients of the flow and temperature distributions for one spent fuel assembly starting the assembly removed from reactor core at 100 hours. The heat transfer capability such as the calculated heat transfer coefficients is compared to the correlations used in RELAP 5, so that justifications can be made by using these correlations in RELAP 5