Determination of gas-liquid bubble column instantaneous interfacial area and void fraction by a real-time neutron radiography method

In this work, the axial profiles of a gas-liquid bubble column instantanous interfacial area and void fraction are determined by a RTNR method. The void fraction was also determined independently from liquid level and an ultrasonic transmission method for comparisons. In the sieve plate apparatus, there is no net flow of liquid, and the gas phase is dispersed homogeneously by the plate into bubbles of approximately equal size across a 5.4 cm ID aluminum tube. The results show that the mean bubble diameter increases slightly with increasing superficial gas velocity. The interfacial area increases sharply at low gas flow rates (Ugs⩽0.007m/s). As the mean bubble diameter becomes almost constant, the interfacial area increases slightly with superficial velocity. Detailed discussion will be given axial profiles and of void fraction and interfacial area.