立体传质塔板CTST喷射性能实验研究

立体喷射型塔板的喷射状况对气液两相接触面积有重要影响。本文利用直径570mm的实验塔，采用高速摄像仪对CTST的喷射过程进行了研究，并基于不稳定波动理论建立了液滴群平均粒径的计算模型。结果表明：喷射孔气速是影响喷射锥角的主要因素，随着喷射孔气速的增加喷射锥角逐渐增大，当喷射孔气速超过7.5 m/s左右时，喷射锥角较为恒定，其数值稳定在55°左右。随着气速的增加喷射孔处液膜速度显著增大，而液体流量增加时液膜速度稍有减小，越靠近喷射孔顶端液膜速度越大。喷射区域内液滴的分布密度接近于Rosin-Rammler分布，在喷射锥角[20o, 40o]范围内的液滴数量比较集中，随着气速和液体流量的增大，液滴分布密度逐渐趋于均匀。液滴群平均粒径随气速的增加而减小，随液量的增加略有增大。正常工作范围内的液滴群平均粒径范围为1.0~2.5 mm。

Spray Characteristics Study of Combined Trapezoid Spray Tray

The spray behaviors of the Trapezoid Spray Tray (CTST) have a significant effect on the gas-liquid interface. In this paper, the spray process of CTST in a column of 570 mm in diameter was experimentally investigated by using a high-speed camera, and a theoretical model of the average droplet size was established according to the unstable wave theory. The results demonstrated that gas velocity passing through the hole is the key factor affecting the spray angle, which increases gradually with an increase in the gas velocity. When the gas velocity exceeds 7.5 m?s-1, the spray angle becomes stable around 55°. The velocity of the liquid sheet at the spray-hole increases significantly with an increase in the gas velocity, whereas decreases slightly with an increase in the liquid flow rate; moreover, it increases from the bottom of spray hole to the top. The distribution density of drop number in the spray area can be described by the Rosin-Rammler function. In addition, the drops mainly concentrate in the area of the spray angle between 20° to 40°, and it gradually becomes uniform with the increase of the gas velocity and of the liquid’s flow rate. The average drop size deceases with an increase in the gas velocity, whereas increases slightly with an increase in the liquid flow rate. In the normal working range, the average drop size is about 1.0 to 2.5 mm.