Numerical investigation on the heat transfer characteristics of unstable steam jet under different operating conditions
Numerical investigation on the heat transfer characteristics of unstable steam jet under different operating conditions
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不同工况下不稳定蒸汽射流传热特性的数值研究
DOI：
10.1016/j.ijheatmasstransfer.2021.121761
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发表时间：
2021
影响因子：
5.2
通讯作者：
Yan Junjie
中科院分区：
文献类型：
--
作者：
Song Shilin;Zhao Quanbin;Chong Daotong;Chen Weixiong;Yan Junjie
对不同工况下非稳定蒸汽射流的相间传热特性进行了瞬态数值研究。气泡半径变化率、界面换热系数和总凝结质量通量在气泡缩颈阶段达到最大值。界面换热系数和气泡半径变化率的最大峰值随着入口压差和水过冷度的减小而减小。界面换热系数和内部速度的峰值出现在气泡颈区。在整体力平衡的基础上，分析了相间传热对气泡生长和颈缩阶段的影响。在气泡生长阶段，动量力起主要作用;在气泡颈缩阶段，凝结力起主要作用。在气泡快速颈缩阶段，冷凝力先下降，达到最小值。随后，冷凝力迅速增加，促进了气泡颈缩运动。不同条件下的凝聚力曲线具有相同的变化规律。
Transient numerical study was performed to investigate the characteristics of interphase heat transfer in unstable steam jet under different operating conditions. Bubble radius change rate, interfacial heat transfer coefficient and overall condensation mass flux reached their maximum values during the bubble necking stage. The maximum peak value of interfacial heat transfer coefficient and bubble radius change rate decreased with the decrease of inlet pressure differential and water subcooling. The peak values of interfacial heat transfer coefficient and internal velocity were found in the bubble neck region. The effect of interphase heat transfer on bubble growth and necking stages was analyzed on the basis of overall force balance. Momentum force played a major role during the bubble growth stage, and the condensation force had a dominant effect on bubble necking stage. Condensation force first decreased and reached its minimum value during bubble rapid necking stage. Subsequently, the condensation force rapidly increased and promoted the movement of bubble necking. Moreover, the condensation force curves under different conditions had the same change law.