Performance Evaluation of a Multi-Branch Liquid-Gas Pipe Separator using Computational Fluid Dynamics
MetadataShow full item record
The present thesis aims to evaluate the performance of a multi-branch gas-liquid separatorby means of 3D computational fluid dynamics (CFD). Thus, numerical simulations of thetwo-phase system were performed using various operating conditions to determine the potentialof such a separator in terms of separation efficiency and slug handling capacity. Theseparation efficiency was measured by quantifying the liquid carry over and gas blowby. The capability of 4 multiphase models in a commercial software to represent realistic flowdistributions and separation of an oil-gas mixture in the multi-branch separator was evaluated.The inhomogeneous mixture model was the multiphase model providing the mostrealistic results and best convergence behaviour and was employed for simulations performedto quantify the performance of the separator. The effect of the pressure difference between the two outlets on separation performancewas analyzed using multiple different pressures in the gas outlet. A small variation in outletpressure was found to have a large effect on the flow distribution. Optimal operatingconditions regarding the pressure difference between the two outlets have been found. Inletconditions with various volume fractions showed a small effect on the gas separationperformance and no effect on the liquid separation performance and flow distribution. Hydrodynamic slug flow at two different frequencies was studied. A high separationperformance, similar to simulations with stable inlet conditions, was seen for the high-frequencyslugs while the longer slugs resulted in a slightly reduced performance. Thus,the multi-branch separator showed well slug-handling abilities for the studied slug flowconditions.