Abstract Collapse of superheated vapor bubbles in subcooled water is studied from the viewpoint of possible mechanisms of premixed zone formation in stratified vapor explosions. Numerical modeling is performed for spherically symmetric bubble collapse in subcooled water, with different initial vapor superheats. The kinetic energy of liquid flow generated due to vapor collapse is obtained. It is shown that the primary mechanism triggering vapor collapse and water flow is vapor cooling in the bubble by colder interface, lowering the vapor pressure and generating necessary pressure drop. Results are compared with an idealized case of bubble vapor maintained at the saturation conditions corresponding to water temperature. Two-dimensional simulations of bubble collapse near solid wall are performed by the boundary element method. Implications to stratified vapor explosions are discussed, and correlations for possible splashing of melt due to the impact of water jets generated by a collapsing steam bubble are obtained.

中文翻译：

---

过冷水中过热汽泡破裂产生的能量和冲量评价

摘要 从分层蒸汽爆炸中预混区形成的可能机制出发，研究了过冷水中过热蒸汽泡的溃灭现象。数值模拟是针对过冷水中球对称气泡坍塌的，具有不同的初始蒸汽过热度。获得由于蒸汽塌陷而产生的液体流动的动能。结果表明，触发蒸汽坍塌和水流的主要机制是气泡中的蒸汽通过较冷的界面冷却，降低了蒸汽压力并产生了必要的压降。结果与气泡蒸汽保持在与水温对应的饱和条件下的理想情况进行了比较。采用边界元法对实体壁附近气泡坍塌进行二维模拟。