Development of proposed guideline of flow-induced vibration evaluation for hot-leg piping in a sodium-cooled fast reactor

Sakai, Takaaki; Yamano, Hidemasa; Tanaka, Masaaki; Ono, Ayako; Ohshima, Hiroyuki; Kaneko, Tetsuya*; Hirota, Kazuo*; Sago, Hiromi*; Xu, Y.*; Iwamoto, Yukiharu*; et al.

Proceedings of 15th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-15) (USB Flash Drive), 13 Pages, 2013/05

The development of flow-induced vibration evaluation methodology has reached a milestone that separate-effect experimental data under a high Reynolds number regime including swirl and deflected inflow conditions are available for the validation of the methodology. On the other hand, technical standards are desirable to be documented for designers of sodium-cooled fast reactors. From such a background, the documentation of a flow-induced vibration design guideline has been made for the hot-leg piping of Japan sodium-cooled fast reactor. This paper describes the design guideline of the flow-induced vibration evaluation methodology, which has been informed from main separate-effect experiments, as well as supplemental interpretation for the guideline.

LSTF test on cet performance during PWR hot leg small-break LOCA and RELAP5 analysis

Takeda, Takeshi; Otsu, Iwao; Nakamura, Hideo

Proceedings of 15th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-15) (USB Flash Drive), 12 Pages, 2013/05

Evaluation model of bubble-type gas entrainment

Ito, Kei; Ezure, Toshiki; Ohno, Shuji; Kamide, Hideki

Proceedings of 15th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-15) (USB Flash Drive), 11 Pages, 2013/05

The gas entrainment (GE) is one of important issues in the study on sodium-cooled fast reactors. In this paper, the authors propose a unified evaluation model of the bubble-type GE, which can predict the onset condition in various experiments. This evaluation model consists of two equations; one is the mechanical balance equation at the gas core tip, the other shows the ratio of the critical gas core length to the specific radius of the free surface vortex. To check the validity of the proposed model, several experiments, e.g. Baum's experiment, are evaluated. As a result, the model gives the similar onset conditions to the experimental results.

Effects of fluid viscosity on occurrence behavior of vortex cavitation; Vortex structures and occurrence condition

Ezure, Toshiki; Ito, Kei; Kimura, Nobuyuki; Onojima, Takamitsu; Kamide, Hideki; Kameyama, Yuri*

Proceedings of 15th International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-15) (USB Flash Drive), 12 Pages, 2013/05

An experimental study on vortex cavitation was carried out in a cylindrical water tank to clarify how the viscosity of fluid influences on vortex cavitation occurrences. Vertical and horizontal velocity distributions were obtained under several experimental conditions, where the kinematic viscosity of water and the velocity of suction flow were varied as parameters. As the results, the flow patterns and the vortex structures, such as the circulation around the vortex, were grasped. And also, the acceleration behavior of vortex from the bottom of tank towards the intake of suction nozzle was clarified. Then, the occurrence map of vortex cavitation was also improved by using the present experimental data.