New interfacial drag force model including effect of bubble wake, (II) - Model validation using experimental data of steam-water bubbly flow in large-diameter pipes

In the previous study, we proposed a new interfacial drag force model based on experimental data of steam water bubbly flow in a large-diameter pipe. This is because our experimental results had suggested that effect of bubbl e wake should he included in the interfacial drag force model, although it half not been taken into account in the existing models. A preliminary meth od for including the effect of bubble wake was hence developed and used in the new model. A new bubble size prediction method was also adopted in the model. In the present study, after improving the measuring equipment and si gnal processing procedure, another series of experiments was carried out. U sing the new experimental data, the methods of predicting bubble size and e ffect of bubble wake were slightly modified. To test the validity of the ne w model, predicted results were compared with available experimental data s ets of steam-water bubbly two-phase flow in large-diameter pipes. One-dimen sional and two-dimensional two-fluid models were used for the calculation. Comparisons shelved that the new model is in good agreement with the experi mental data whereas the model which does nut take into account the effect o f bubble wake overestimated the void fractions.