Sodium pool combustion test Run-F7; Interim report

Futagami, Satoshi  ; Nishimura, Masahiro ; Kawata, Koji; Ishikawa, Hiroyasu ; Miyahara, Shinya  

Supposing sodium leak accident from a IHTS pipe in FBR, sodium pool combusion test Run-F7 series is under way to know liner peak temperature and to study sodium pool growth and combustion behavior in the case of small-scale sodium leaks (0.01ton/hr) in an air atmosphere. This report consists of a result of Run-F7-1 (Feb,17,1998) and Run-F7-2 (Apr, 21, 1998) : In these tests, sodium temperature and sodium leak rates are the same (about 0.01ton/hr), but the height of leak point was changed. The test was performed using FRAT-1 (Fission Product and Radioactive Aerosol Release Test Rig . volume : 3m) of SAPFIRE (Safety Phenomenology Tests on Sodium Leak, Fire and Aerosols) facility. A burning pan (diameter : about 1000 mm, thickness : 6 mm) made of carbon steel (SM400B) to simulate floor steal liner was installed in FRAT-1. a 5kg of sodium was leaked at the leak rate of 0.01ton/hr under the temperature of 507C from the height of 0.1m and 1.5m (Run-F7-1 and Run-F7-2, respectively) during 30minutes when air was continued to feed into the cell. From the results, the following conclusion were drawn concerning the liner peak temperature, and sodium pool growth and combustion behavior, in the small-scale (0.01ton/hr) sodium leak: (1)In this case (1eak rate 0.01ton/hr), burning pan thermocouple measured 616C at approximately 33minutes in Run-F7-1, and 675C at 33minutes in Run-F7-2. therefore, the height of leak point has an effect on liner peak temperature. (2)Post test observation clarified that the deposits covered an area of about 0.3m in both tests. Sodium pool growth velocity during experiments were also similar. therefore, the height of leak point doesn't have a notable effect on sodium pool growth. (3)In both tests, burning rate of a unit area was 16kg-Na/mhr. (4)Analysis of the chemical composition of the deposits on the burning pan revealed that the main compounds were sodium oxides, but sodium dioxide and ...