逆载对管道内汽水两相流临界热流密度的影响

Effect of inverse load on critical heat flux of steam-water two-phase flow in a tube

利用旋转平台对逆载作用下矩形通道内汽水两相流临界换热进行了实验研究。通过改变逆载大小、入口流体过冷度、流体质量流速等参数,获得了静止和逆载作用2种状态下矩形管道内汽水两相流临界换热实验数据。实验结果表明,质量流速随着加热时间的增长而减小,进出口压差则反之;临界状态下,质量流速随着逆载、过冷度的增大而减小;进出口压差随着逆载、质量流速的增大而增大,随着过冷度的增大而减小;临界热流密度值随着逆载、质量流速、入口过冷度的增大而增大;其中逆载对临界热流密度的影响最为显著,在逆载从0g^2.5g变换范围内,临界热流密度可提高50%。

An experimental investigation using a rotating platform was performed to obtain the critical heat transfer performance of steam-water two-phase flow in a rectangle tube under inverse load. By changing the pa- rameters such as magnitude of inverse load, inlet subcooling and mass flow rate, the critical flow and heat transfer data of steam-water two-phase flow boiling under static and inverse load were obtained. The results show that mass flow rate decreases with continuous heating, but the variation of fluid pressure difference in the test section is opposite. At critical state, mass flow rate decreases with increasing inverse load and/or inlet subcooling. Fluid pressure difference increases with increasing inverse load and mass flow rate, and decreases with increasing inlet subcooling. The critical heat flux increases with increasing inverse load, mass flow rate and inlet subcooling. Inverse load greatly impacts critical heat flux. Within its changing range from 0 g to 2.5 g, the critical heat flux could be increased by 50%.