2 0 0 0 VOF法による単一気泡の数値解析
- 著者
- 富山 明男 宋 明良 南川 久人 坂口 忠司
- 出版者
- 一般社団法人日本機械学会
- 雑誌
- 日本機械学會論文集. B編 (ISSN:03875016)
- 巻号頁・発行日
- vol.57, no.539, pp.2167-2173, 1991-07-25
- 被引用文献数
- 6
In order to examine the feasibility of direct simulation of bubbly flows, the applicability of the VOF (volume of fluid) method to the analyses of a single rising bubble was examined in this study. Calculated bubble shapes and terminal velocities under wide ranges of Eotvos number and Morton number were compared with the experimental data summarized by Grace et al. Except for the cases when bubble shapes are spherical-cap and skirted, the VOF method could predict them well by assigning only eight cells to the bubble diameter. Hence, it was confirmed that some modification of this method will enable us to simulate bubbly flows directly under a wide-range of flow conditions. Moreover, the relation between a bubble shape and velocity distribution was examined within the ranges in which the VOF method is valid. It was found that the secondary vortex appearing in wobbling bubbles induces the velocity component normal to the bubble interface, and this velocity is one of the causes of the wobbling shape of the bubble.
1 0 0 0 OA ロッドバンドル内スペーサ近傍気泡流動のマルチスケール実験・計算融合評価技術の開発
沸騰水型原子炉燃料集合体設計における実規模試験依存度低減に資する流動評価手法として, (a)ロッドバンドル及びロッド支持体(スペーサ)構造を適正に考慮し, かつ目的に応じた適正な空間分解能で気泡流動を評価できるハイブリッド計算技術、及び(b)ロッド間隙部形状及びスペーサ構造が気泡挙動と液相速度場に及ぼす影響を正確に測定し, ハイブリッド計算遂行に必要な実験相関式を構築するための複雑流路内気泡・液相流動実験技術を開発するとともに, (c)この2種の技術を融合統合化したロッドバンドル内スペーサ近傍気泡流動評価技術を開発した.