This is the second of two papers which discuss a transient two-fluid model for the simulation of slug flow in pipelines. In the first paper, new constitutive relations for the drag coefficient and the virtual mass force for the slug flow regime were derived. To account for the non-uniform distribution of the phases and of the pressure drop along a slug unit, new coefficients in the pressure gradient term in the momentum conservation equations for the gas and the liquid phases were also obtained. In this paper, the new components of the transient two-fluid model are validated by comparing the model predictions for gas (or liquid) fractions and pressure drops for steady-state and transient slug flow in pipes to available numerical and experimental data. These comparisons show the potential of the present approach to predict general transient slug flow problems in pipelines.