| dc.description.abstract | The present thesis aims to evaluate the performance of a multi-branch gas-liquid separator
by means of 3D computational fluid dynamics (CFD). Thus, numerical simulations of the
two-phase system were performed using various operating conditions to determine the potential
of such a separator in terms of separation efficiency and slug handling capacity. The
separation 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 flow
distributions and separation of an oil-gas mixture in the multi-branch separator was evaluated.
The inhomogeneous mixture model was the multiphase model providing the most
realistic results and best convergence behaviour and was employed for simulations performed
to quantify the performance of the separator.
The effect of the pressure difference between the two outlets on separation performance
was analyzed using multiple different pressures in the gas outlet. A small variation in outlet
pressure was found to have a large effect on the flow distribution. Optimal operating
conditions regarding the pressure difference between the two outlets have been found. Inlet
conditions with various volume fractions showed a small effect on the gas separation
performance and no effect on the liquid separation performance and flow distribution.
Hydrodynamic slug flow at two different frequencies was studied. A high separation
performance, similar to simulations with stable inlet conditions, was seen for the high-frequency
slugs while the longer slugs resulted in a slightly reduced performance. Thus,
the multi-branch separator showed well slug-handling abilities for the studied slug flow
conditions. | |
