Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Okamoto, Koji*; *
JNC TY9400 2000-016, 90 Pages, 2000/06
JNC-TY9400-2000-016.pdf:2.53MB
no abstracts in English
The Japan Society of Multiphase Flow*; Special Committee for Examination of Thermohydraulic Analysis Code based on Three-Fluid Model*
PNC TJ9565 92-001, 173 Pages, 1992/05
The purpose of the present study is to improve a numerical analysis method for multiphase flows based on the three-fluid model. The improvement will be conducted for the following three items; (1)modeling of the multiphase flow, (2)constitutive equations (3)numerical method. A systematic survey was carried out for the aforementioned three items. As a result, a reliable plan for the improvement was proposed. Experimental database for air-steam and air-water two-phase annular flow was also presented in this report, which will be useful for the future improvement of the constitutive equations. As for the numerical method, a method for improving the computational efficiency was proposed. It was confirmed that the CPU time decreases about 95% with the proposed method.
Nakayama, Hiromasa; Katata, Genki*
no journal, ,
Dry deposition is important process of chemical material input of gaseous and particulate forms from the atmosphere into the terrestrial ecosystem near the ground surface in the planetary boundary layer. It is difficult to accurately estimate dry deposition amounts for such areas. First, we incorporate our particle dry deposition scheme into the loca-scale high-resolution atmospheric dispersion model and perform test simulations in comparison to indoor experiments. Next, we apply to the hilly-terrain forest in a field-site to analyze the impact of topography and forest structure to dry deposition. It is found that the model successfully simulated the maximum values at the edge of the forest and exponential decrease with a downwind distance from the edge as well as the experiments. Furthermore, for the field-site, the distribution of dry deposition shows a peak at the forest edge, rapidly decreases with a downwind distance from the edge. Although the local decrease is observed at the forest gap, that shows nearly constant within the canopy.
Sato, Takumi; Hirata, Naoya*; Oikawa, Katsunari*; Nagae, Yuji; Kurata, Masaki
no journal, ,
Macroscopic segregation of molten core and melt components occurs with slow cooling rate in the accident of Fukushima Daiichi Nuclear Power Plants. In this study, solidification and microscopic segregation are simulated with the Scheil model and thermal properties calculated by Thermo-calc in order to investigate an influence of cooling conditions on macroscopic segregation. A macroscopic segregation behaviour has been calculated for UO
-ZrO-FeO system, which are major oxides of molten core materials. According to calculated results, UO and ZrO was concentrated in initial solidification area. On the other hand, FeO were strongly concentrated in later solidification area. In addition, macroscopic segregation tends to be suppressed in the conditions of fast solidification rate and slow velocity of solidification interface.