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LedaFlow ® is a new transient multiphase flow simulator which includes 1D multi-fluid models consisting of mass, momentum and energy conservation equations for each field (continuous, bubble and droplet), as well as compositional tracking. In this paper, a new method called Slug Capturing is employed for slug flow, and the results analyzed and compared with the field data of two different fields. Additionally, for some cases, differences between the new simulator and another commercially available transient code results are compared and analyzed.The first case corresponds to the production of a TOTAL-operated field in the UK. Produced fluids from the wells are transported through a 21 km long, 16-inch multiphase flowline from the well platforms to the central receiving facilities. The multiphase line (gas/oil/water) must be operated in a narrow range of pressure and flow rate conditions in order to avoid severe slugging issues. Flow patterns are compared for various water cuts and superficial gas velocities. When severe slugging is observed, slug characteristics (frequency, length) are analyzed and compared to simulator predictions.The second case is from a CONOCOPHILLIPS-operated North Sea asset. The 3-phase, 18-inch ID oil flow line runs 3.7 km from a wellhead platform to a central processing platform. The line drops approximately 6 m over the last 3 km before flowing up a 130 m riser. The pipeline exhibits severe riser slugging which is not adequately modeled by conventional transient models, due to the complex interplay between hydrodynamic and riser slugging, as well as 3-phase effects. Slug frequencies and lengths are analyzed and compared to predictions.

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We report the development and testing of steady-state point models for two-phase gas-liquid and oil-water flow in pipes. A new point model for gas-viscous oil compared well with flow loop data using dense gas (SF6) and viscous oil. However, the flow regime prediction and the modeling of the transition from laminar to turbulent flow regime were found to be in need of further improvement. Data from stratified viscous oil-water experiments were analyzed using the point model for liquidliquid flow. Traversing gamma densitometry was used to characterize the oil-in-water emulsion layer. Analysis of the measurements confirms the assumption of a flat interface between oil-continuous and water-continuous layers.