Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Toda, Shinichi; Yoshikawa, Shinji; Watanabe, Osamu*; Kishida, Masako*; Oketani, Kazuhiro*
JNC TN4400 2003-005, 106 Pages, 2003/05
JNC-TN4400-2003-005.pdf:3.82MB
The improved version of the MSG code(Multi-dimensional Thermal-hydroulic Analysis Code for Steam Generators) has been released. It has been carried out to improve based on the original version in order to calculate reverse flow on water/steam side, and to animate the post-processing data. To calculate reverse flow locally, modification to set pressure at each divided node point of water/steam region in the helical-coil heat tansfer tubes has been carried out. And the matrix solver has been also improved to treat a problem within practical calculation time against increasing the pressure points. In this case pressure and enthalpy have to be calculated simultaneously, however, it was found out that using the bloci-Jacobean method make a diagonal-dominant matrix, and solve the matriz efficiently with a relaxation method. As the result of calculations of a steady-state condition and a transient of SG blow down with manual tip operation, the improvement on calculation function of the MSG code was confirmed. And an animation function of temperature contour in the sodium shell side as a post procssing has been added. Since the animation is very effective to understand themal-hydraulic behavior on the sodium shell side of the SG, especially in case of transient condition, the analysis and evalution of the calculation results will be enabled to be more quickly and effectively.
*; Kishida, Masako*; *
JNC TJ9440 2000-013, 80 Pages, 2000/03
JNC-TJ9440-2000-013.pdf:4.93MB
In this work, analyses on sodium-water reaction temperaturc in the new SWAT-1(SWAT-1R) test were completed by the CHAMPAGNE code in order to understand void and velocity distribution in sodium system, which was difficult to be measured in experiments. The application method of the RELAP5/Mod2 code was investigated to LMFBR steam generator(SG)blow down analysis, too. The following results were obtained. (1)Analyses on sodium-water reaction temperature in the SWAT-1R test. (a)Analyses were carried out for the SWAT-1R test under the condition water leak rate 600 g/s by treating thc pressure loss coefficient, the interface friction coefficient and the coefficient related to reaction rate as parameters. The effect and mechanism of each parameter on the shape of rcaction zone were well understood by these analyses. (b)The void and velocity distribution in sodium system were estimated by use of the most suitable parameters. These analytical results are expected to be useful for planning of the SWAT-1R test and evaluation of test result. (2)Investgation of the RELAP5/Mod2 code. (a)The items to be improved in the RELAP5/Mod2 code were clarified to apply this code to the FBR SG blow down analysis. (b)One of these items was an addition of the shell-side (sodium-side) model. A sodium-side model was designed and added to the RELAP5/Mod2 code. Test calculations were carried out by this improved code and the basic function of this code was confirmed.
*; *; Kishida, Masako*
PNC TJ9678 98-001, 294 Pages, 1997/09
The steam generator (SG) tube rupture phenomenon due to overheating by sodium-water reaction is considered as an important issue on SG safety evaluation and has been studied intensively. At this phenomenon, the cooling effect by the water/steam flow inside the tubes plays a significant role. Therefore, it is important to define the cooling effect by analyzing the behavior of the water/steam side during normal operation and during water/steam blow-down for overheating failure evaluation. In this work, the cooling effect was analyzed by a FBR SG blow-down analysis code, BLOOPH, and was corrected by taking the generated heat from the sodium-water reaction into account. In these analyses, the capacity and the operation method of the SG blow down system were treated as parameters. In order to confirm validity of the BLOOPH code, a similar analysis was carried out for the reference case by the thermal-hydraulic analysis code, RELAP5/Mod.2, that has been used widely for analyses of the LOCA phenomena of LWRs. The following results have been obtained by this work. (1)The effect of the capacity of the SG blow-down system on the SG blow-down characteristics has been well understood. A method has been found for reducing the time duration of the small flow rate which might occur inside the tubes during the blow-down. (2)A methodology has been established to design the most optimum SG blow-down system. (3)Analyses have been perfomed to define the cooling conditions needed for overheating failure evaluation. (4)The results by the code BLOOPH and RELAP5 have shown a reasonably good agreement regarding the water/steam pressure and the hydraulic behavior during the blow-down for the reference blow-down system. The validity of the BLOOPH code has been confirmed. (5)Research and development items have been clarified to improve the BLOOPH code in future.
*; Kishida, Masako*; *; *
PNC TJ9678 96-005, 86 Pages, 1996/03
The LMFBR concept without secondary sodium system is considered to be one of the most promising concepts for plant cost reductions. In this type of LMFBR, steam generators(SGs) are directly equipped in the primary sodium system. Therefore, the evaluation of effects of sodium-water reaction products (SWRPs) to the reactor core in case of SG tube rupture becomes one of the major safety issues. In this work, SMAC-13E, the thermal-hydraulic analysis code for sodium-water reaction developed by Power Reactor and Nuclear Fuel Development Corporation, was improved so as to evaluate the transport of SWRPs in the primary sodium system containing reactor core. In this improvement, SWRPs transport model (REACT), that treats solution, precipitation, deposition and so on, was added and it was intended that REACT is independent of the original part of SWAC-13E as much as possible. The improved analysis code (new SWAC-13E) was applied to the evaluation of SWRPs transport phenomena of typical planned LMFBR plant without secondary sodium system. The results of this analysis were qualitatively reasonable, and it was confirmed that the new SWAC-13E was applicable to the evaluation of the transport behavior of SWRPs.
Watanabe, Osamu*; Kishida, Masako*; Shirataki, Koji*; Hirazawa, Yoshiya*
PNC TJ906 79-02, 109 Pages, 1979/12
Water leak detectors-hydrogen concentration meters are equipped with secondary cooling system of LMFBR to detect small leak of water from heat transfer tube in steam generator. Leak rate region to be able to detect the water leaks before secondary tube failure is decided by using the concept of so-called "safety map". Computer code "SWAC-10-MJ/2" provides the safety map for secondary cooling system of proto-type reactor. This paper is written for user's manual of the code. Performance of "SWAC-10-MJ/2" code is as follows; (1)Secondary cooling system of proto-type LMFBR is selected for calculation object. (2)Wastage rate equations proposed by PNC are accepted. (3)The relation between the initial leak rate and the enlargement of the leak hole is enabled to be feeded as an input. (4)The enlargement by self wastage is taken into account in calculating the change of hydrogen concentration. (5)Effect of mixing of hydrogen in sodium is introduced for plenum regions. (6)Detectability of water leak in stagnant sodium (in the down-commer region) by means of hydrogen detectors is enabled to be evaluated. (7)Movement of hydrogen between sodium and cover gas is enabled to be evaluated. (8)Hydrogen diffusion process in Ni membrance of hydrogen detector is introduced. (9)The number of calculating points of leak rate is 50 points, and the range of calculation time is about 20,000 seconds. (Time mesh size; 4 seconds and Calculating step; 5,000 steps) By the way, the region size needed is about 470KB and the computing time for IBM 370/168 is about 0.83 msec/point of leak rate/step.
*; Kishida, Masako*; Watanabe, Osamu*
PNC TJ206 77-27VOL2, 135 Pages, 1977/03
PNC-TJ206-77-27VOL2.pdf:7.37MB
None
*; Kishida, Masako*; Watanabe, Osamu*
PNC TJ206 77-27VOL1, 84 Pages, 1977/03
PNC-TJ206-77-27VOL1.pdf:3.01MB
None