格納容器及び原子炉建屋内におけるエアロゾル沈着量評価手法の開発,3; CFDによる原子炉建屋内におけるエアロゾル沈着効果の基礎検討

Development of the evaluation method for the aerosol deposition amounts in the containment vessel and the reactor building, 3; Basic study on the aerosol deposition effect in the reactor building using a CFD

堀口 直樹   ; 宮原 直哉; 上澤 伸一郎  ; 吉田 啓之  ; 逢坂 正彦  

Horiguchi, Naoki; Miyahara, Naoya; Uesawa, Shinichiro; Yoshida, Hiroyuki; Osaka, Masahiko

軽水炉事故時において格納容器から原子炉建屋内に漏洩するエアロゾルの建屋内沈着量評価手法を開発するための基礎検討として、粒子に関する沈着量分布及び建屋における除染係数の傾向の把握を目的に、簡易的な建屋形状及び流動条件を想定したCFD解析を実施した。建屋への沈着が有意に起こる可能性及び粒径が大きいほど低階層に留まりやすく建屋内除染係数が大きくなる傾向など、建屋内のエアロゾル移行挙動及び沈着効果に係る基礎知見を取得した。

As a basic study to develop an evaluation method for aerosol deposition amounts in a containment vessel and a reactor building during LWR severe accident, to understand the tendency of the aerosol particle deposition and the decontamination factor, the behavior of the leaked aerosol from the reactor in the building was simulated by CFD on simplified condition of the building shape and the flow. As a result, the basic knowledge associated to the transportation and the deposition of the aerosol particles in the building was obtained, which is the possibility of the significant deposition for the decontamination in the building, and the tendency that the bigger aerosol particles is, the easier they deposit on the lower floors and the higher the decontamination factor becomes.