A112 PIVによる鋼の焼入れ中の沸騰および蒸気膜の可視化
2003 年 23 巻 Supplement2 号 p. 9-12
詳細
2003 年 23 巻 Supplement2 号 p. 9-12
During quenching process, steam film and boiling bubbles occurring on the boundary layer between quenching steel and quenchant often lead to uneven heat transfer and in turn distortion and heterogonous microstructure in quenching steel. In this paper, experiments of stirring quenching to induce forced conventional flow and to break boiling film are carried out. The formation and movement of boiling bubbles and forced convectional flow are investigated with a high speed camera. Visualization of boiling bubbles and forced flow are performed by PIV-PTV methods. Furthermore, cooling curves of a steel cylinder during quenching are measured and the heat transfer coefficient between quenchant and steel is identified. Finite element simulation is performed to analyze the flow effect on heat transfer. By combining analysis of visualized flow from measurement and simulation, the behaviors of steam film and forced flow are clarified and improvement on heat transfer by stirring is confirmed.
