Abstract
This paper concerns the simulation of three-phase flows in an oil production system operated by TotalEnergies. The system consists of several flowlines connected to near-vertical risers at water depths up to 1300 meters. In most of the cases, more than 90% of the pressure is lost in the risers, even though all the risers are operated using gas lift.
The cases were simulated using LedaFlow versions 2.6 and 2.7, and the results showed that the pressure drop predictions obtained using LedaFlow 2.7 were significantly more accurate than with LedaFlow 2.6. The most pertinent difference between these two LedaFlow-versions is that LedaFlow 2.7 contains an important model improvement relevant for three-phase near-vertical flows, where the effect of liquid droplets on the gas bubble capacity of the continuous liquid is accounted for.
At very high water cuts (≥65%), bench measurements showed that the rheological behaviour of the oil/water emulsions is very important and at the same time very complex, exhibiting a non-Newtonian behaviour. This made pressure drop predictions more difficult. For these cases, uncertainties in the emulsion rheology had to be accounted for to establish realistic error bounds for the predictions.
The cases were simulated using LedaFlow versions 2.6 and 2.7, and the results showed that the pressure drop predictions obtained using LedaFlow 2.7 were significantly more accurate than with LedaFlow 2.6. The most pertinent difference between these two LedaFlow-versions is that LedaFlow 2.7 contains an important model improvement relevant for three-phase near-vertical flows, where the effect of liquid droplets on the gas bubble capacity of the continuous liquid is accounted for.
At very high water cuts (≥65%), bench measurements showed that the rheological behaviour of the oil/water emulsions is very important and at the same time very complex, exhibiting a non-Newtonian behaviour. This made pressure drop predictions more difficult. For these cases, uncertainties in the emulsion rheology had to be accounted for to establish realistic error bounds for the predictions.