Experimental study on thermal stratification in compact reactor vessel of sodium cooled fast reactor; Effects of core outlet velocity and temperature difference during scram

Kimura, Nobuyuki; Hayashi, Kenji; Tobita, Akira; Kamide, Hideki ; Nagasawa, Kazuyoshi*

Thermal stratification water experiments using a 1/10th scale model were carried out for an advanced loop type sodium cooled reactor. Experimental parameters were core outlet velocity, temperature difference during scram, and height of the plug which infill the hole at the dipped plates for setup of a fuel handling machine. It was found that the height and the rising speed of stratification interface depended on the Richardson number. Furthermore the temperature gradient of the stratification interface depended on the Peclet number.