Sekine, Ichiro*; Yamada, Tsutomu*; Sekiguchi, Takashi*; Fujita, Tomo; Nakanishi, Tatsuro
Doboku Gakkai Heisei-23-Nendo Zenkoku Taikai Dai-66-Kai Nenji Gakujutsu Koenkai Koen Gaiyoshu (DVD-ROM), p.69 - 70, 2011/09
no abstracts in English
Higuchi, Kenji; Hiratsuka, Atsushi*; Endo, Tatsuro; Ota, Yukihiro; Machida, Masahiko
JAEA-Data/Code 2010-025, 84 Pages, 2011/02
We describe the parallelization and performance evaluation of the simulation program for emission of terahertz electromagnetic wave from high-Tc cuprate superconductors, where high performance was achieved as a result of tuning on multi-core system. Firstly the simulation space was divided for parallel processing, where MPI communication was implemented. The divided simulation space was further assigned to processes on multi-processors. Secondly parallel performance on each processor was accelerated by multi-threads implemented by OpenMP with a ratio at the number of core's. We have evaluated the parallelized program on HA8000 cluster system at Information Technology Center of the University of Tokyo, and, thus, achieved high performance in the analysis of terahertz electromagnetic wave emission from superconductors.
Sato, Kazuhiko*; Sato, Koichi*; Yoshida, Tetsushige*; Taniguchi, Hiromi*; Goko, Tatsuro*; Ito, Takashi; Oishi, Kazuki*; Higemoto, Wataru
Physica B; Condensed Matter, 404(5-7), p.600 - 602, 2009/04
Zero-field muon spin relaxation was measured for organic antiferromagnet '-(BEDT-TTF)ICl under high pressure of up to 1.37 GPa. Neel temperature, which is 22 K at ambient pressure, increases with increasing pressure and becomes approximately 48 K at 1.37 GPa. Muon precession frequency at 1.37 GPa, becomes about 5 times larger than that at ambient pressure.
*; *; *; Iguchi, Tatsuro*
PNC TN941 84-74, 103 Pages, 1984/05
Sodium flow and endurance test for "MONJU" dummy fuel subassembly of the 6th test production (abbreviated name ,M6CWP) was carried out in Sodium Flow Test Loop. This test was performed for 2,384 hours with the inlet sodium temperature of 397C, the flow rate of 17.36 kg/sec and the cold trap temperature of 120C. The results of this test showed that; (1)The initial average pressure loss coefficient C of M6CWP was given by following equation. C = 113.58 Re. (2)In the measurement of total pressure, the increase of pressure loss became, to saturation at about 300 hours after the beginning of the test and finally approached to 3% larger than the initial value. (3)AS a result of the sodium draining conducted in accordance with the design condition for "MONJU" EVST (Ex-vessel Storage Tank), it was found that the sodium of about 90g remained in the subassembly. (4)The eye inspection of the subassembly after the test showed that the subassembly was intact without separation of fuel pins from knock bars. Since this was the final test for "MONJU" dummy fuel subassembly of test production, this report summarized the total pressure liss increase and various points concerning endurance found in the test series until now.
*; Abe, Sadayoshi*; Iguchi, Tatsuro*
PNC TN941 84-69, 39 Pages, 1984/04
The flow induced vibration of a fuel pin bundle is considered to be one of the major factors causing wear marks observed on "JOYO" MK-I fuel claddings. This experiment was performed by using a fuel pin bundle having porosity/ring of twice as large as that of "JOYO" MK-I fuel assembly, in order to study the effect of porosity/ring on the flow induced vibration of pins. The following was clarified from the comparison between the results of this experiment and the previous one using the test bundle of porosity/ring equal to that of "JOYO" MK-I fuel assembly. Any significant fuel pin vibration was not observed in the deformed bundle test in which the deformed pins were lined up on the outermost row simulating thermal bowing of the fuel assembly irradiated in reactor, because the restrain effect of the deformed peripheral pins was larger than that of porosity/ring. The similar result ,had been obtained in the previous experiment. In the test of normal bundle without any deformed pin, the fuel pin vibration was much larger in this experiment than the previous one. This experimental result showed that the effect of porosity/ring on the vibration was significant in the normal bundle.
Abe, Sadayoshi*; *; Iguchi, Tatsuro*
PNC TN941 84-67, 30 Pages, 1984/04
The objective of this experimental study is to obtain the data on pressure loss characteristics of the fuel assembly which must be deformed during hypothetical core disruptive accident (HCDA). Three of deformed bundle and one of normal shaped bundle were used in the experiment. These bundles had the same geometry as the fuel bundle part of "Monju" blanket assembly. The main conclusions are as follows: The pressure loss (P) of deformed bundle at the same Reynolds numbers as normal bundle can approximately predicted by using the ratio of cross sectional flow area(A), as shown below. (P(deformed))/((normal)) = (A(normal)/A(deformed)). This equation is applicable with the following limitations. (1)Reynolds numbers defined at bundle area is 10 to 310. (2)Reduction of flow area is within 17% of flow area of normal bundle. Prediction area of the equation is less than 8% and 3% for the range of Reynolds number of 10 to 810 and 810 to 310, respectively.
Yoshikawa, Shinji*; Iguchi, Tatsuro*
PNC TN941 84-26, 110 Pages, 1984/02
SSC-L(Super System Code - Loop version) is a thermo-hydraulic transients analysis code in LMFBRs, developed at Brookhaven National Laboratory in USA. This code is capable of both analyses of normal operation and accident. It allows free allocation of the components in heat transport systems, and arbitrary representation of the heat transport systems. Since the introduction of this code in June 1980, a large effort has been devoted to facilitate and validate the use of the SSC code for MONJU plant transient analysis. This report describes analysis of reactor shutdown transient in MONJU plant from full-power operation to natural circulation with simultaneous all pumps trip. In this transient a pressure loss characteristics of the primary loop and a frictional characteristics of the primary pump dominate coolant thermohydraulic behavior. In order to investigate the sensitivity of the loop and pump characteristics for the transient, following two cases were analized. (1)Characteristics of the loop pressure loss and the pump frictional torque based on the physical theory and experimental data. (2)Under the natural circulation, pressure losses of core, check valves, and stopped pumps have great effect on flow rate. Results are summarized as follows: (1)Flow coastdown transient up to natural circulation is characterized by the pump speed. In the range of flow rate under 50% of the rated value, the pump frictional torque plays a important role in the determining the flow rate. (2)Under the natural circulation, pressure losses of core, Check valves, and stopped pumps have great effect on flow rate. (3)The maximum coolant temperature at the top of the core during the transient is determined by the degree of mismatch of thermal power and flow rate. In this analysis, the maximum coolant temperature, is higher than both in full power operation and in natural circulation.
*; *; *; Iguchi, Tatsuro*
PNC TN941 84-06, 8 Pages, 1984/01
Experimental investigation were performed on the combined radiation and natural convection heat transfer through the cover gas space over the sodium pool. The amount of heat transmitted from the hot sodium to the cold wall through the gas space folled with sodium mist was measured. The thermophysical properties such as the thermal emissivities of liquid sodiim and mist-deposited stainless steel and the radiative characteristics of mist-filled space were also measureed using especially devised anparatus. The amount of heat transmitted through the space, measured by experiments, was compared with the analytical results based on the measureed thermophysical properties. The agreement was comparatively good between the experiment and analysis.
*; Iguchi, Tatsuro*; ;
Proceedings of 3rd International Conference on Liquid Metal Engineering and Technology in Emergy Production, 0 Pages, 1984/00
*; Abe, Sadayoshi*; *; Iguchi, Tatsuro*
PNC TN941 84-42, 29 Pages, 1983/03
Hydraulic test and sodium soaking were carried out for "JOYO" MK-II Core Materials Irradiation Test Assembly (CMIR) and Structual Materials Irradiation Test Assembly (SMIR). The results were as follows. (1)The pressure loss coefficient of CMIR was 75.6 at Reynolds number of 1.58 10. This result agreed well with its design value. (2)The total pressure loss of SMIR was 0.5806 kg/cm at 0.5 kg/sec. And the pressure loss of the orifice of SMIR was 0.5194 kg/cm at 0.5 kg/sec. (3)Sodium soaking, sedoum draining and preheating tests of CMIR and SMIR were performed under simulated plant conditions. The test result obtained will be reflected to the actual post irradiation examinations together with the cleaning test and disassembling test to be conducted by other sections.
*; *; *; Iguchi, Tatsuro*
PNC TN941 83-33, 35 Pages, 1983/03
Sodium flow endurance and cleaning tests were carried out for special A-type dummy fuel assembly. The endurance test was performed for 1278 hours with the sodium temperature of 600C, the flow rate of 10kg/sec, and the cold trap temperature of 120C. The sodium cleaning for the assembly was performed by using water and alcohol. The results of this test are as follows. (1)The pressure loss coefficient was 6.56 at Reynolds number of l.710. This result agreed well with that of measured water flow test. (2)Any time-depending change of the pressure loss coefficient was not observed during the sodium flow endurance test. (3)The weight of remaining sodium in the assembly after the tests was about 48 grams. Neither deformation nor defect were found by visual inspection of the assembly after the tests. Therefore, it is concluded that the assembly does not have any difficulty in the flow characteristics, the durability and the cleaning characteristics. The test results obtained will be reflected to the actual design and fabrication of A-type fuel assembly.
*; *; Abe, Sadayoshi*; Iguchi, Tatsuro*
PNC TN941 83-32, 64 Pages, 1983/03
The A-type fuel assembly has two kinds of irradiation ducts which contain "Monju" and "Joyo" MK-II fuel pin arrays. In this experiment, measurement test of pressure loss coefficient and electrolyte injection test were conducted for both individual elements and assembly. The experimental data can be used to calculate the coolant flow distribution in the A-type fuel assembly. The main conclutions from this experiment are as follows. (1)A wide gap is formed around the irradiation duct when the "Joyo" MKII type irradiation duct is used. The gap should be narrowed by some design improvement to decrease leakage flow. (2)The size of the orifice at the entrance region of the "Monju" type irradiation duct can be determined by using the pressure loss coefficients led from experimental results. (3)The experimental results for flow distribution rates in the irradiation ducts have rather big experimental errors because of the test method to know the rates in the small ducts from the pressure drop in the large driver bundle. Therefore, it is desirable to know correctly thermal-hydraulic characteristics of the assembly by using TED (Temperature Difference) thermometers at the first irradiation.
*; *; *; Iguchi, Tatsuro*
PNC TN941 82-268, 14 Pages, 1982/12
Sodium leak detection system is now under development for quick detection of a small leak from Monju primary systems. In this development, aerosol release rate from leaked sodium is requied to evaluate the delay time for the detection as well as to determine the lower limit of the detectable aerosol concentration. To meet that requirement, the test under the following conditions was made. This was to determine the aerosol release rate from sodium into innert nitrogen enviroment under the primary cell simulated conditions. [sodium temperature : 200 to 550C] [HO content in N : 0.04 to 1.0%] [O content in N : 0, 1.5, and 3.0%] [surface area of sodium : 20 and 80 cm] The test results revealed that the aerosol release rate is sensitive to the oxygen concentration, but not to the water concentration, and has the same temperature coefficient as the sodium evaporation rate into argon gas.
*; *; *; Iguchi, Tatsuro*
PNC TN941 82-197, 32 Pages, 1982/09
To develop in-situ aerosol particle counter, the method to utilize laser beam was selected, and its feasibility test has been carried out. The principle of the method is to measure the gravitational settling velocity of a particle and to calculate a particle size from the settling velocity by using Stokes equation. The particle being measured is sodium mist that is familiar to be handled by the present authors. The test is divided into two steps. In the first step, particle size distribution of mist was measured by a cascade impactor. The ABS code was modified for sodium mist, and numerical study was performed with this code to check reliability of the measured data. In the latter step, the laser counter was used to measure particle size distribution of mist. In this event, the particle size distribution previously obtained in the first step was used as reference data. The results of the present test revealed that the minimum particle size to be detected by the laser counter was about 1.0 m. To meet the requirement as the aerosol counter, particles as small as 0.5 m have to be detected. Hence, it was recognized that the data processing method of the present counter have to be modified.
Miyaguchi, Kimihide*; Sato, Kazujiro; Iguchi, Tatsuro*
PNC TG033 82-01(5), 16 Pages, 1982/01
Several series of thermal and hydraulic experiments have been conducted using full mock-ups of JOYO fuel subassemblies. This paper describes the test results of cross-flow mixing and pressure loss in wire-wrapped pin bundles. It also presents the comparison between cross-flow mixing experiments and calculations by SWIRL code.
*; *; *; Iguchi, Tatsuro*
PNC TN941 81-73, 270 Pages, 1981/04
In R&D of FBR, various kinds of physical properties are used for designing of test loop and analysis of test data. In this report, tables and figures, which are frequently used, are presented for convenience of their easy reference. Physical properties of sodium, argon, helium, 304 stainless steel, 316 stainless steel, and 2.25Cr-1Mo steels are listed up to 800 C. The report is a supplement and revise edition of PNC-report, No. N941 75-19, "Practical use method of Thermophysical properties of Sodium", Published in 1975.
; *; *; *; Iguchi, Tatsuro*
PNC TN941 81-06, 75 Pages, 1981/01
In an sodium test facility, particulate impurities are accumulated with time progresses when it has been operated for long period of times at elevated temperatures. Similar event may also be happen in coolant systems of LMFBR. In particular, deposition of radioactive corrosion products in sodium components and in pipings of a primary coolant system of the reactor may causes in high radiation background around them. But, the fact is that behavior of particulate corrosion products in sodium system is not well understood. No information is available, except few experimental findings. To meet the requirement, a series of tests have been conducted placing their emphasis on determinations of particle sizes, elements compositions, and concentration of particulate in flowing sodium system. Mesh-type and magnetic-type filters were used for these purposes. Results here obtained are summerized as follows. (1)Particulate concentrations of the present sodium loop ranged from 15 ppb depending strongly upon flow velocity in main sodium curculation piping. This suggests that concentration is being controlled by settling of particles. (2)Particle sizes determined ranged from sub-micron to 50 m, while their mean radius was 2-3 m. (3)Main compositional elements of particulates were Fe (18-48%), Cr (4.4-18%), Mn (4-9%), Ni(2-3%), and Si(3-4%). (4)Both the present mesh-type and magnetic-type filters worked effectively for collecting and trapping particulates in the loop sodium.
Ninokata, Hisashi; Iguchi, Tatsuro*
11th LIQUID METAL BOILING GROUP MEETING, ,
Aoki, Yuto; Ito, Rintaro; Kitamura, Akihiro; Omori, Takazumi; Taniguchi, Tatsuro; Ide, Hiroshi
no journal, ,
In this report, we present the validation results of the radiation source inverse estimation computation method and the effectiveness evaluation method of the "estimation system of radiation sources and dose rates" developed by JAEA. As for the validation test, the JMTR was used as the evaluation site, and the results of radiation source inverse estimation computations were compared with measured data. As a result, it was confirmed that the hot spot could be estimated approximately well. As for the effectiveness evaluation, the test field to be established at the NARREC and at the JMTR were used as the evaluation sites, and the effectiveness evaluation items such as the functions of each tool and the process of the system were summarized.