Azuraien Japper-Jaafar

Impacts of Cooling Rates on Voids in Waxy Crude Oil under Quiescent Cooling Mode

When waxy crude oil becomes a gel, predicting a restart pressure in pipelines has been a challenge. The formation of gas voids within the gel following sufficient cooling has an impact on the restarting pressure. This study is aimed at analyzing the effects of cooling rates on voids in waxy crude oil gel using Magnetic Resonace Imaging (MRI) technique. The flow loop rig simulating offshore oil production was designed. Waxy crude oil underwent cooling through the same temperature range to observe the effects of cooling rates on voids formed. Cooling rates were found to have different influence on the formation of voids. A maximum total voids volume of 6.96% was formed at cooling rate of 1.00°C/min. Cooling rate of 0.55°C/min produced a minimum voids volume of 5.74% near pipe wall. Higher cooling rates generally produced higher voids volume near pipe wall and in entire pipe. However, there was no definite trend observed for the voids around pipe core at which slower cooling rates were also observed forming higher voids volume.

CFD Modelling and Validation of Newtonian and Non-Newtonian Fluids in Curved Conduits

CFD modelling of drag reduction agents (also called Flow Improvers) polymer additives dissolved in a newtonian solvent (UTP tap Water) was carried out in a curved conduit, A 7 equation Reynolds stress set of equations was used to simulate this flow. The purpose of this simulation is validate experimental results that show unusual pressure drop behaviour. CFD experiments show that there is pressure build-up near the end of the curved conduit due to severe centrifugal forces produced by the fluid, confirming the validity of the experimental results.