NAFEMS International Journal of CFD Case Studies

Volume 13, September 2023

ISSN 1462-236X
ISBN 978-1-83979-059-1

Numerical Simulation of Gas-Liquid Two-Phase Flow in Inlet Pipe Bend of Separator

Dr. M. Irikura, Mr. T. Ishigami
Chiyoda Corporation, Japan

Mr. C. Heijckers
MySep Pte Ltd, Singapore

Mr. H. Witteveen
KRANJI Solutions Pte Ltd, Singapore

https://doi.org/10.59972/f1yjzkep

Keywords: Gas-liquid separator, two-phase flow, annular flow, bend, elbow, droplet entrainment, mist fraction, numerical simulation

Abstract

Gas-liquid separators are widely used in oil and gas facilities to separate incoming liquid from gas for further processing. Droplet entrainment in the gas stream from a separator can have serious adverse consequences, for instance, damage to downstream rotating machinery. The prediction of separation performance of gas-liquid separators, which is important in order to avoid such operating issues, requires understanding of the mist characteristics in the upstream piping to the separator, and of the separation efficiency of the internals within the separator. The presence of bends in the inlet piping to a separator can have remarkable influence on the characteristics of mist flow entering the separator. Thus, evaluation of the fraction and size distribution of the mist in inlet piping bends is important in the assessment of the separator performance. This paper focuses on the prediction of the mist fraction and size distribution in the inlet piping bends as a first-step in the evaluation of separator performance. A numerical simulation method which reproduces the gas-liquid two-phase behavior in inlet piping bends is proposed. The effect of a bend upon the droplet entrainment and deposition in the piping is evaluated, which allows better understanding in the mechanisms of the two-phase flow within the bend. The predicted mist fractions and mist size distributions at an exit of the bend under various gas and liquid flowrates are compared with experimental data to validate the numerical simulation method and confirm its feasibility. The comparison show that the predicted mist fractions and mist size distributions agree with measurements, although there are some deviations from the measured results. From the results it is concluded that the numerical simulation can be applied for evaluation of the effects of inlet piping arrangements on mist fraction and mist size distributions, which is a key factor in the assessment of separator performance.

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Cite this paper

M. Irikura, T. Ishigami, C. Heijckers, H. Witteveen, Numerical Simulation of Gas-Liquid Two-Phase Flow in Inlet Pipe Bend of Separator, NAFEMS International Journal of CFD Case Studies, Volume 13, 2023, Pages 43-57, https://doi.org/10.59972/f1yjzkep