Reynolds and Grashof Numbers Analysis on Steady State Natural Circulation Flow using FASSIP-02 Large Scale Test Loop

Abstract The Station Blackout incident at the Fukushima Dai-ichi Nuclear Power Plant, which caused the failure of the active cooling system (with a pump) has made research on passive safety systems (without a pump) in nuclear safety technology increasingly developing and becoming an important issue. The focus of the research that researchers will characterize the natural circulation flow based on correlation of non-dimensional number like Reynolds Number, Grashof Number and geometrical ratio for large scale facilities. In addition, other parameters are boundary conditions, such as the difference in the total pipe length, pipe diameter, and the height difference between the heating outlet and the cooling inlet being the determining parameters. The correlation results between Re versus Gr/N G with fixed numbers were a is a 2.89 and b is 0.38, similar to other researchers’ data. These results will be compared with the correlation of non-dimensional numbers Vijayan et.al., the comparison results show that the correlation of non-dimensional numbers in the FASSIP 02 large-scale loop is in the turbulent regime.