矩形窄缝自然循环密度波不稳定特性实验研究

摘要

以去离子水为工质，对其两相自然循环流动不稳定性进行了实验研究，得到了2 mm和5 mm的矩形缝隙条件下的流量变化情况。实验结果分析表明：2mm矩形窄缝的流量波动周期为4～5s，5mm的流量波动周期为5～7 s ；2 mm矩形窄缝的上下振幅对称性不佳，5 mm的上下振幅对称性较好；随着加热量的增加，2 mm和5 mm矩形窄缝的波动周期均会增大。2 mm矩形窄缝随着功率的增加，出现了流量漂移，密度波波动特征减弱。%The experimental study was performed to investigate the flow instability in a natural circulation system by using deionized water , which gained the changeable situation of the flow rate in the narrow rectangle channel at the size of 2 mm and 5 mm . The analysis results show that the periods of wave with 2 mm and 5 mm narrow rectangle channel are 4‐5 s and 5‐7 s respectively ,the symmetrical characteristic of the amplitude of 2 mm is not good as the 5 mm it is ,and the periods of the 2 mm and 5 mm increase with the heating power .With the heating power increasing ,flow excursion phenomenon happens in the channel at the size of 2 mm ,and the characteristic of density w ave w eakens .