A comparative study of the performance of multiphase flow pipeline simulators in a hilly terrain pipeline

Predictions from multiple industrial simulators of multiphase pipeline flow are compared to field data for a hilly terrain, gas-condensate pipeline with three-phase flow. Field conditions studied include quasi-steady flow and ramp-up slugging. Some models predict excessive terrain-induced slugging for which there is little evidence in the field. The models that do not predict such predominant slugging are less accurate than others in predicting the timing and volume of ramp-up slugs. It is argued that these deficiencies of model prediction result from insufficiently accurate calculation of even steady-state holdups under conditions of large pipe inclination and three-phase flow. Other comparisons across simulators, and against experimental or field data, suggest that divergences in prediction are attributable to a few aspects of modelling, such as regime transitions, interfacial friction, and liquid-liquid dispersal.