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Uehara, Akihiro*; Akiyama, Daisuke*; Ikeda, Atsushi; Numako, Chiya*; Terada, Yasuko*; Nitta, Kiyofumi*; Ina, Toshiaki*; Takeda-Homma, Shino*; Kirishima, Akira*; Sato, Nobuaki*
Journal of Nuclear Materials, 559, p.153422_1 - 153422_11, 2022/02
Times Cited Count：3 Percentile：50.96(Materials Science, Multidisciplinary)Koga, Jiro*; Shinzato, Takushi*
JNC TJ8400 2000-054, 48 Pages, 2000/02
JNC-TJ8400-2000-054.pdf:1.23MB
The "STELLA" which is a tool for simulation of dynamical systems applied to the numerical simulation of the behavior of minor constituent, such as hydrazoic acid, forming and extinguishing on the operation of reprocessing process. The concentration of hydrazoic acid forming by the reaction of nitrite and hydrazine were determined by use of STELLA after the determination of concentration of main constituents by MIXSET-X. The results from simulation is shown that the STELLA is applicable to the numerical simulation of the behavior of minor constituent.
; *; Yoshida, Eiichi; Aoto, Kazumi
JNC TN9400 2000-011, 33 Pages, 1999/03
JNC-TN9400-2000-011.pdf:13.45MB
The damage was observed in rupture disk for the A-loop superheater of sodium-water reaction products releasing system for MONJU on March 3, 1998. Low temperature creep and stress corrosion cracking tests were carried out as the causes investigation of the damage. As the result, the followings are clarified. (1)The possibility that low temperature creep is the principal damage is small. (2)The stress corrosion cracking under NaOH environment due to the reaction of Na vapor and moisture condensed on the surface of glass beads as remains is the most probable cause on the damage. (3)Comparatively many glass beads remained in damaged surface. The gap between rupture disk and vacuum support was narrower than other parts, and they were not directly exposed to the Na vapor for a long time. The above factors caused the perfect intergranular cracking by stress corrosion. Since NaOH was chemically changed into the harmless Na
O on the location except for damaged zone by full Na vapor, the stress corrosion cracking was not generated.
*
JNC TJ9400 99-001, 78 Pages, 1999/03
For studies on incineration of long-lived fission products (LLFPs) in a fast reactor, detailed characteristics of reactor core such as incineration performance have to be investigated. Therefore, accurate neutron cross section data of LLFPs become necessary. In the present study, in order to perform the precise measurements of keV-neutron capture cross sections of Tc-99, which is one of most important LLFPs, the details of the Tc-99 sample and the measurements with our experimental facilities were investigated.
; Miyake, Osamu;
PNC TN9410 98-037, 81 Pages, 1998/04
The sodium combustion computer code ASSCOPS has been developed for analyses of thermal consequences (i.e.pressure and temperature time histories) of sodium leak accidents in FBR plants. Version 2.0 of ASSCOPS, that is used in the study of this report, includes improvements and additional models over the previous versions. This report describes the validation of ASSCOPS (version 2.0) by using sodium pool combustion tests data obtained from FAUNA (F5, F6) at KfK, Germany, and SOLFA-1 (Run-D1) at PNC. The validation includes comparisons of calculation results of ASSCOPS (Version 2.0) with experimental data, and with calculation results of the previous version of ASSCOPS (Version 1.1). Furthermore, the effects of reaction products ratio (NaO:NaO), initial humidity in the atomsphere, and radiation coefficient from the sodium pool to the gas were studied. The following results have been obtained from the study. (1)The calculation results agree well with the experimental data of the gas, sodium, and structure temperatures, and gas pressures. (2)The reaction products ratio (NaO:NaO) is one of the most important parameters for sodium combustion evaluation. It affects the pressure and temperature due to the difference of the reaction heat. Selection of proper value for this parameter results in the best estimate of the pressure, temperature and oxygen concentration. The ratio of NaO: NaO = 60: 40 is adequate for the purpose of conservative evaluation. (The analysis under the oxygen concentration below 10 % assumes NaO: NaO = 100: 0) (3)Initial humidity concentration in the air has been more little affect to the pressure and temperature than the reaction products ratio or the radiation coefficient of pool surface affect. (4)The radiation coefficient of pool surface was surveyed around the value obtained by conventional evaluation. The results shows that suppression of radiative heat transfer ...
; Yoshida, Eiichi; Furukawa, Tomohiro; Aoto, Kazumi
PNC TN9410 97-092, 87 Pages, 1997/07
This experiment is carried out in the series of the investigation on the damage mechanism of carbon steel. In this paper, the damage situation is considered by structure observations. The test were carried out in 600
C-1200C temperature range, in blowing an argon gas. The reagents are NaO, NaO and NaOH. From structure observations, the holes are observed on the surface of iron-base material in some test conditions. This result is indicated that the selective reaction occurs. The selective reaction is more obvious as the time exposed to the high temperature is longer. It is considered that the selective reaction occurs after the chemical reaction between iron-base material and sodium compound. The areas, in which Mn-concentration is higher, are observed in products on the surface of specimen.
Hirota, Koichi; H.Maetzing*; H.-R.Paur*
JAERI-Conf 95-003, 0, p.615 - 619, 1995/03
no abstracts in English
Hirota, Koichi; H.Maetzing*; H.-R.Paur*; K.Woletz*
Radiation Physics and Chemistry, 45(4), p.649 - 655, 1995/00
Times Cited Count：46 Percentile：96.08(Chemistry, Physical)no abstracts in English
Hirota, Koichi; K.Woletz*; H.-R.Paur*; H.Moetzing*
Radiation Physics and Chemistry, 46(4-6), p.1093 - 1097, 1995/00
Times Cited Count：17 Percentile：82.2(Chemistry, Physical)no abstracts in English
*; *; *
PNC TN941 85-127, 92 Pages, 1985/08
RECT-II (the Removal test of reaction products by cold trap) was conducted by use of SWAT-3 (the Steam Generator Safety Test Facility) at PNC in order to construct the post-accident operation of steam generators of the prototype FBR Monju and a larger plant following it. In prior to the test, some amount of the sodium-water reaction products (SWRP) generated in the water injection test (Run 18) was remained in the sodium system. An objective of the test is to confirm the purifying method to remove SWRP by hot sodium circulating through a cold trap (CT). A meshless type cold trap was selected to avoid choking by impurities and to enable efficient SWRP removal. RECT-II started on April 4, 1984 and terminated on April 26 when the plugging temperature decreased to 187C. Major results obtained in the test are as follows: (1)Post-test observation revealed that the SWRP having remained at the bottom of the evaporator and the sodium outlet pipe were completely removed through the purification operation. (2)Hence, it is concluded that after the hot draining the SWRP of 14 kg-H0 remained in the sodium system out of that generated by the 42 kg-H0 injection and that almost all of the former was removed through the operation. (3)However, some amount of the hydrocarbon-oxide and SWRP in the slit articles simulating crevice and stagnant region still remained after the operation. Then it is concluded that it is insufficient to remove SWRP in crevice and stagnant region by the circulation of hot sodium. (4)A mass transfer coefficient of oxygen is evaluated as 2 
10
[g/(mm H ppm)] if the cross section of the evaporator and inner surface of the 8 inch horizontal pipe are assumed to be the entire surface area of SWRP. (5)Since the choking of the cold trap degrades the efficient SWRP removal, it is essential to develop a cold trap which hardly chokes and easily regenerates even after choking; one of answers for this request is a ...
Shimoyama, Kazuhito; Kurihara, Akikazu; Kikuchi, Shin; Umeda, Ryota
no journal, ,
Self-wastage comes from water/steam leak through the penetrating crack caused in the steam generator tube of sodium-cooled fast reactor. When the self-wastage proceeds to inside wall of tube, breach area and water leak rate will be larger, then, it will be likely to spread the affected area caused by sodium-water reaction. It is very important to clarify the self-wastage behavior for locally affected region and detection of the water leak in real plant. In the 1st report, the authors have performed the self-wastage experiments for the pinhole type micro crack. In this report, fatigue crack type self-wastage experiments were carried out to evaluate the effect of wastage form/geometry and water leak rate, it was confirmed that initial defect geometry, such as pinhole and fatigue crack, does not strongly influence to self-wastage rate.
Kawaguchi, Munemichi; Miyahara, Shinya; Uno, Masayoshi*
no journal, ,
no abstracts in English
Kawaguchi, Munemichi; Miyahara, Shinya; Uno, Masayoshi*
no journal, ,
Sodium-concrete reaction (SCR) experiments in sodium-cooled fast reactors were performed to reveal the phenomena that the reaction gradually terminates by the sedimentation effect of the reaction products. In addition, some physical properties of the reaction products (density, specific heat, melting point) were measured after SCR experiment.
