Development of integrated numerical analysis model for unsteady phenomena in upper plenum and hot-leg piping system of Japan sodium-cooled fast reactor

JSFRの上部プレナム及びホットレグ配管系における非定常現象解析統合モデルの開発

高屋 茂  ; 田中 正暁  ; 藤崎 竜也*

Takaya, Shigeru; Tanaka, Masaaki; Fujisaki, Tatsuya*

ホットレグ配管の流力振動は、JSFRの設計において重要な検討課題である。ホットレグ配管内の流動場は、配管入口における乱れの影響を受けると考えられることから、上部プレナムを含めた体系に関して、非定常流動解析を実施した。また、既存の縮尺試験の結果との比較により、解析結果の妥当性を確認した。更に、ホットレグ配管の振動解析モデルを試作し、非定常流動解析結果を入力条件として解析を実施した。

Flow-induced vibration of hot-leg pipings is one of concerns for the design of Japan Sodium-cooled Fast Reactor (JSFR) which is now being developed. The flow field in the hot-leg pipings is supposed to be affected by flow disturbances at the entrance, so it is important to evaluate flow fields including the upper plenum. In this study, a simulation model of the upper plenum and the hot-leg piping system of JSFR was developed. Unsteady fluid flow analyses were then conducted by unsteady Reynolds averaged Navier-Stokes simulation (URANS) with Reynolds stress model. The appropriateness of the calculated results was discussed by comparing available scale model test results. Furthermore, a prototype model for vibration analysis of the hot-leg piping was developed. In the model, the transient pressure data predicted by the URANS were used as input data for the vibration analysis.