Simulation of accumulation and sweep-out of liquid in a low elbow of a gas/liquid pipeline

MSc- project of Gerbrand Koren

 

The aim of this project is to obtain fundamental insight in the fluid mechanics of liquid accumulation and transport in gas and oil pipelines. If the gas velocity is low, liquid will remain in the pipeline, until it is swept out from the pipeline as a liquid slug. This frequently occurs in pipeline applications in the gas and oil industry, where liquids (i.e. oil/condensate and water) or transported together with hydrocarbon gas. Liquid accumulation can be undesired as this can cause pipeline corrosion (in the presence of water pools), or can give unstable flow behaviour where the liquid slugs may flood the downstream separator. Sometimes liquid accumulation may also be desired, for example during an emergency blow-down, where the gas is produced through a flare system and the liquid should preferably remain in the pipeline.
 
In this project a simulation of the two-phase flow is carried out in FLUENT. Here, the low elbow is pre-filled with liquid, and thereafter the gas velocity is gradually increased to visualize when and how liquid starts to be swept with the gas out of the elbow. Results will be compared with experimental data available in the literature as well as with lab experiments.
 
Supervisors: Prof. drir. R.A.W.M. Henkes and drir. M.J.Tummers