Slug Frequency Prediction Model for Fluid Flow in Flowline Bends

The prediction of slug frequency for two-phase slug flow during multiphase transportation of oil reservoir productions is crucial in the design of slug controllers for petroleum processing installations. Mechanistic based slug prediction models have not had much successful application due to the difficulty in modelling the non-linear interface motion during slug development. The mechanism of slugging in offshore flowline-riser is complicated and requires rigorous experimental sampling and testing. This process can be time-consuming and costly. In this study, a new correlation is developed for the prediction of severe slugging frequency. The new model is developed based on the results of scaled experimental design. Dimensional analysis approach using the Buckingham pi-theorem is used in developing the two-phase correlation. The model development involves non-dimensional empirical correlations in terms of relevant dimensionless groups, which are obtained based on the design of the experiment. A broad range of experimental data from 10 varied choke opening size was used. The new correlation predicts 92.3% of the measurements within ±8% absolute error and the mean absolute deviation of the correlation is about 6.13%. The newly developed correlation can be applied for flow rates between 0.1 kg/s and 0.6 kg/s and choke openings between 10-98%.