竖直管内弹状流向搅混流转变界限的判定

Method of Determining the Transition Boundary of Slug Flow to Churn Flow in Vertical Tubes

本文对两种不同管径的竖直管内弹状流向搅混流转变界限的判定进行了实验研究。实验发现,在弹状流向搅混流转变的过程中,管内压力会随气体流量的增加出现先降低后上升的非单调性变化。通过对管内压力和摩阻变化的理论分析,并在可视化观察的基础上,提出压力变化曲线的转折点即为搅混流产生的起始点。然后根据实验数据,绘出两种不同管径下的搅混流转变界限。

Experimental studies on determining the transition boundary of slug flow to churn flow are pressure and friction loss,the turning point of inside pressure curve is just the point where the churn flow takes place.According to the experimental data,the transition boundaries of slug flow to churn flow in two carried out in two tubes,which inside diameters are 15mm and 25mm,respectively.The results show that during the transition,the inside pressure experiences the changeable process from decrease to increase with the increase of the air flow rate.Based on the visual observation and the theoretical analysis of the inside different tubes are given.