Experimental study on aerosol transport behavior in multiple cells with expandable connecting pipe for safety assessment of sodium-cooled fast reactors

Umeda, Ryota; Kondo, Toshiki; Kikuchi, Shin; Kurihara, Akikazu

Proceedings of 28th International Conference on Nuclear Engineering (ICONE 28) (Internet), 9 Pages, 2021/08

https://doi.org/10.1115/ICONE28-61200

In this study, in order to obtain the fundamental information on aerosol transport behavior between cells, the Multiple cells with Expandable connecting pipe Test facility (MET) was manufactured and preliminary experiments were performed. In the preliminary experiments, simulated particles were used in a test system with two cells connected horizontally or vertically, and their transport behavior was measured. As a result, it was possible to confirm the behavior of the simulated particles transporting to the horizontal or vertical cells from the results such as images and sedimentation data.

Basic test on sodium fire protection systems (III); Simulation Test, Run-B3 of a design basis sodium leak from the Monju IHTS

Himeno, Yoshiaki; ; Kawada, Koji*; Kawabe, Ryuhei*; *; *; Miyaguchi, Kimihide

PNC TN941 85-130, 65 Pages, 1985/09

PNC-TN941-85-130.pdf:2.49MB

Test of sodium fires in an auxiliary building of the fast reactor has been conducted by use of a test rig in which reduced scale models of a sodium pipe, a floor liner, a sodium drain pipe, and a smothering tank were installed to simulate the configuration of fire mitigation systems in the reactor. In the test, a 150kg sodium at temperature of 505 C was spilled from the model sodium pipe at flow rate of 1 /sec for 3 minutes. Then a whole accident sequence that starts from a sodium spill and ends at a self-extiguishment of fire within the smothering tank was studied. From the test results obtained and through their analysis, the following conclusions were drawn. (1)A whole sodium leak and fires accident sequence proceeded as expected in the Monju design, i,e., a spilled sodium was smoothly drained into the smothering tank via the floor liner and the drain pipe, then sodium fire was self-extinguished in the smothering tank. (2)In regard to the model sodium pipe, failures of the thermal insulation jackets due to sodium corrosion and due to generated sodium combustion heat are not found. The thermal insulation jackets kept its original geometries and functioned propely as a barrier to prevent the dispersion of spilled sodium into the atmosphere during the test. No flow blockage of a spilled sodium occured both on the floor Liner and in the drain pipe. Combustion heat of mixed fires (a columnar fire and a pool fire) that occured within an accident cell of the test rig was determined to be 1.6 times of that of a pool fire. This value is not so large as expected and indicates that the mild fires proceeds during the test. (3)With the smothering tank, temperatures data of sodium, steel liner, perlite concrete, and structural concrete were obtained. The data of concretes indicated that the structural concrete was not heated so high as to interfere its structural integrity. A total water released from the concretes per unit surface area of the liner ...

Basic test on sodium fire protection systems

Kawabe, Ryuhei*; Himeno, Yoshiaki; *; *; *

PNC TN941 84-124, 56 Pages, 1984/08

PNC-TN941-84-124.pdf:3.89MB

At Sodium Leak-Fire Basic Test Rig (SOFT-1), three tests were performed, which were : (1)Run-A1 : For the aim of understanding the sodium combustion phenomena, 180 sodium was burnt in an open pool, and temperature transients in sodium was measured and burning rate were determined. (2)Run-B1 : For the evaluation of efficiency of fire suppression board, burning sodium was covered by a slitted board and change in burning rate was observed and drain test was performed using 530 C sodium to confirm the function and integrity of draining pipe. (3)Run-B2 : In order to clarify the burning-hydraulic behavior of sodium on liner, 505C, 180 sodium was discharged onto 1.2m2.4m steel plate with 1/100 gradient, and temperature transients and mass of residuum were measured. Following results were obtained. (i)When sodium was heated up to 400C and exposed to air, the sodium was ignited. (ii)The surface temperature reached 650 C, 7 min. after the ignition and the temperature was almost constant from that. (iii)Under a conservative condition where air flowed over the fire suppression board by forced convection, the sodium burning rate and the aerosol generating rate where pool surface were covered by fire suppression board (opening area 1%) was about 3 % and 5 % of those in open pool burning respectively. (iv)The maximum heat flux to the draining pipe wall reached 1.210 W/m. Any cracking, however, was not found on the draining pipe wall even by color check. (v)In the liner test Run-B2, on the liner there remained large amount of sodium oxide, which worked as wick, and the soaked sodium burned after sodium supplying finished, resulting liner temperature 643 C which was higher than the supplied sodium temperature. The amount of sodium oxide was 8.7kg/m on the liner after the test. (vi)The maximum temperature, flow velocity and burning rate of sodium on liner and maximum heat ...

Formation of volatile radioiodine compounds in sodium pool burning

; ; ;

Journal of Nuclear Science and Technology, 12(11), p.717 - 721, 1975/11

https://doi.org/10.3327/jnst.12.717

no abstracts in English

Behavior of sodium oxide aerosol in a closed chamber

; ; ; ;

Journal of Nuclear Science and Technology, 10(9), p.566 - 573, 1973/09

https://doi.org/10.3327/jnst.10.566

no abstracts in English

Investigation of multi-dimensional effect observed in sodium columnar fire test

Ohno, Shuji

no journal, , 

Characteristics of sodium combustion and subsequent heat transfer behaviors were investigated in detail based on the measurement in the test which was conducted with the main focus on the multi-dimensional thermal-hydraulics during a large leak rate sodium column and splashing fire.

Study on safety enhancement of the fast reactor by using nanoparticle suspension sodium, 13-5; Reaction suppression

Nagai, Keiichi; Saito, Junichi; Ara, Kuniaki

no journal, , 

no abstracts in English