Sodium fire test at broad ranges of temperature and oxygen concentrations, 4; Low temperature sodium spray tests (Translated document)

Kawata, Koji; Matsuki, Takuo*; Miyahara, Shinya

JAEA-Review 2011-046, 42 Pages, 2012/02

JAEA-Review-2011-046.pdf:2.41MB

Sodium spray fire tests at an initial sodium temperature of 250C were conducted under the atmospheric conditions of air and 3% oxygen containing nitrogen to determine both the sodium burning rate and the aerosol release fraction.

None

Kawada, Koji

Saikuru Kiko Giho, (27), p.80 - 83, 2005/06

https://rdreview.jaea.go.jp/gihou/pdf3/n27-12.pdf

We carried out reflection seismic and multi-offset VSP surveys at JNC Shobasama-site to develop the investigation technique in the granite area, and evaluated the applicability of these geophysical methods. As the result of this study, we consider that a) It is possible to infer the existence of the lower angle fracture zone in the granite by reflection seismic survey and b) Multi-offset VSP supplements the result of reflection seismic survey and it is possible to infer the distribution of the fracture zone in deeper area in the granite.

Research and Development of FBR

Saikuru Kiko Giho, (21), 121 Pages, 2004/00

https://rdreview.jaea.go.jp/gihou/pdf2/n21-17.pdf

https://rdreview.jaea.go.jp/gihou/pdf2/n21-22.pdf

None

Research and Development of FBR

Kawada, Koji

Saikuru Kiko Giho, (24), 66-70 Pages, 2004/00

https://rdreview.jaea.go.jp/gihou/pdf2/n24-09.pdf

https://rdreview.jaea.go.jp/gihou/pdf2/n24-14.pdf

None

Development of Blow Down Model for the LEAP Code; Validation by Data of Sodium-Water Reaction Tests

Jitsu, Koji; Ono, Isao*; Kawada, Koji; Kurihara, Akikazu; Yatabe, Toshio

JNC TN9400 2003-062, 84 Pages, 2003/06

JNC-TN9400-2003-062.pdf:1.29MB

It is one of the important matters to select the design base leak (DBL) of the steam generator (SG) of a fast breeder reactor (FBR) in sodium-water reaction. The selection of the DBL has an influence on safety, economical efficiency, etc. of the plant.It is necessary to develop the computational model to estimate the sodium-water reaction phenomenon with high accuracy and rationality for selecting the DBL of large SGs. The blow down evaluation on overheating tube failure phenomenon is pointed out as part of the necessary improvements, since the behavior of overheating tube failure is largely affected by the steam conditions inside of the tube.This document shows the validation of blow down model for the LEAP code, which is developed as analysis code for failure propagation of the SG tubes, by test's data in Sodium-Water Reaction Test Rig No.1 (SWAT-1R). The following results have been obtained through the validation.(1) Within the mass flow rate ranging from 160 to 540 g/s in SWAT-1R, it has been confirmed that calculated internal pressure shows good agreement with the test's one. The pressure in tests becomes close to the calculation by Ogasawara model in critical flow models.(2) Mass flow rate is appropriately calculated of the test after about 10 seconds in the beginning of test. Calculated mass flow rate by Ogasawara model is closer to the test than that by Moody model.(3) On both Moody model and Ogasawara model in critical flow models, internal pressure in calculation shows the underestimation of HT-3 test. It will be necessary to investigate this reason.(4) Mass flow rate at the pipe near water heater tank shows the large overshoot in the beginning of test. Also, the small overshoot that supposed to be moved from upper stream appears at the nozzle about 2 seconds. Since these overshoots are estimated too large, these phenomena should require to be examined.(5) As calculated mass flow rate at the nozzle in both critical models have a tendency to be evaluated l

Research and Development of FBR

Saikuru Kiko Giho, (20), 0 Pages, 2003/00

https://rdreview.jaea.go.jp/gihou/pdf2/n20-14.pdf

https://rdreview.jaea.go.jp/gihou/pdf2/n20-19.pdf

Focusing on the cover layer materials (as the Radon Barrier Materials), which could have the effect to restrain the radon from scattering into the air and the effect of the radiation shielding, we produced the radon barrier materials with crude bentonite on an experimental basis, using the rotary type comprehensive unit for grinding and mixing, through which we carried out the evaluation of the characteristics thereof.

Sodium pool combustion test Run-F7; Interim report

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

PNC TN9410 98-074, 154 Pages, 1998/08

PNC-TN9410-98-074.pdf:4.94MB

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 ...

Investigation for the sodium leak in Monju sodium leak and fire test-I

Kawada, Koji; Ohno, Shuji; Miyake, Osamu; ; ; Tanabe, Hiromi

PNC TN9410 97-036, 243 Pages, 1997/01

PNC-TN9410-97-036.pdf:12.29MB

As a part of the work for investigating the sodium leak accident which occurred in Monju on December 8, 1995, three tests, (1)sodium leak test, (2)sodium leak and fire test-I, and (3)sodium leak and fire test-II, were carried out at OEC/PNC. Main objectives of these tests are to confirm leak and burning behavior of sodium from the damaged thermometer, and effects of the sodium fire on integrity of the surrounding structure, etc. This report describes the result of the sodium fire test-I carried out as a preliminary test. The test was performed using SOLFA-2 (Sodium Leak, Fire and Aerosol) facility on April 8, 1996. In this test, sodium heated to 480C was leaked for approximately 1.5 hours from a leak simulated apparatus and caused to drop onto a ventilation duct and a grating with the same dimensions and layout as those in Monju. The main conclusions obtained from the test are shown as below. (1)Observation from video cameras in the test revealed that in early stages of sodium leak, sodium dropped down out of the flexible tube of thermometer in drips. This dripping and burning were expanded in range as sodium splashed on the duct. (2)No damage to the duct itself was detected. However, the aluminum louver frame of the ventilation duct's lower inlet was damaged: Its machine screws had come off, leaving half of the grill (on the grating side) detached. (3)No large hole, like one seen at Monju, were found when the grating was removed from the testing system for inspection, although the area centered on the point that the sodium attacked was damaged in a way indicating the first stages of grating failure: The 5-mm- square lattice was corroded through in some parts, and many blades (originally 3.2 mm thick) had become like the blade of a sharp knife. (4)The burning pan underside thermocouple near the leak point measured 700C in roughly 10 minutes, and for the next hour remained stable between 740C and 770C. There was a ...

Development of ceramic liner for FBR building

Himeno, Yoshiaki; Morikawa, Satoshi; Kawada, Koji; Yorita, E.*; Fujiwara, T.*; Kaneshige, T.*; Irie, S.*

PNC TN9410 91-092, 11 Pages, 1991/01

PNC-TN9410-91-092.pdf:1.53MB

To develop a ceramic liner, a selection test of materials, an improvement test of selected material, and a feasibility test of the liner have been conducted.in the selection test, fifty commercially available high temperature cement and ceramics were subjected to thermal shock test (tst), sodium exposure test(set), and sodium flame exposure test (sfet). From test results, alumina/silicon-carbide (AlO-sic)mixture base castable refractory was selected in consideration of material cost, and material availability for a simpler liner construction in the buildings. The selected material was subjected to the improvement test. from the test, proper weight fractions of additives such as alumina cement and silica were determined. Drying conditions were also determined. Finally, a sodium burning pan made of concrete whose inner surfaces were covered with the improved AlO-sic base castable refractory was fabricated and was used for a sodium burning test.

Sodium fire test at broad ranges of temperature and oxygen concentration (II); The sodium burning rate and aerosol release rate in Nitrogen atmosphere

Kawada, Koji*; ; *; Himeno, Yoshiaki

PNC TN9410 88-164, 28 Pages, 1988/12

PNC-TN9410-88-164.pdf:1.59MB

[Purpose]A sodium pool fire test has been conducted in low oxygen containing nitrogen atmosphere to determine the sodium burning rate and aerosol release rate and compare them with calculated results by the SOFIRE-MII code. [Method]After installing a burning pan in a 3m test vessel, FRAT-1, the test vessel was filled with nitrogen gas includlng 3% in volume of oxygen gas. Then, the test was started by supplying a sodium (175400C) in the burning pan. The sodium burning rate was determined from the consumption rate of oxygen in the test vessel. The aerosol release rate was determined from total aerosol mass recovered. [Result](1)The sodium burning rate depends on the sodium pool temperature. As the result of a comparison of the experimental sodium burning rate values with the calculated ones by the SOFIRE-MII code, it was cleared that the former was lower than the latter in case of sodium pool temperature below 400 C and its differance was more than one order of magnitud at 175C. This reason is based on the fact that the burning rate is controlled by the masstransfer of oxygen at high pool temperature, while it is controlled by the reaction between oxygen and sodium at low pool temperature. In final, an empirical formula that agree with the experimental results was derived. (2)The aerosol release rate also depends on the sodium pool temperature. It is less than about 10% of the sodium burning rate. Assuming that the aerosol release rate is propotional to the sodium burning rate, an empirical formula which dependends on sodium pool temperature giving the maximum value at each sodium pool temperature was decided.