Experiments of hydrogen behavior in the cover gas and sodium space of the LMFBR's SG; Studies of leak detector developments on LMFBR's SG (4)

not registered; Kuroha, Mitsuo; not registered; Daigo, Yoshimichi; not registered; not registered

Various tests were conducted in SWAT-2 to investigate the hydrogen behavior both in the cover-gas and in the sodium by using the In-cover gas and the In-sodium hydrogen meters. The results of the hydrogen injection tests, the water injection tests and the bubble rising velocity measurment tests are presented in this report. The conclusions that were drawn from these tests are the followings. (1)Traveling velocity of hydrogen gas in the cover gas was dominated by the buoyancy and the convection rather than by the diffusion. (2)The background hydrogen partial pressure in the cover gas did not become lower than 10 Torr. This lower limit was two to three orders of magnitude higher than the hydrogen pressure in sodium. (3)The experimentally determined bubble rising velocity in sodium agreed well with the theoretical prediction. (4)The detection rate of cover gas hydrogen that was not disolved into sodium was determined to be about 20Z, and that of hydrogen disolved into sodium to be about 80% with the present test vessel. (5)The hydrogen disolution rate during the water injection tests was higher than that of the hydrogen injection tests.