Investigation of the Thermal Effects on the Flow Resisting Properties of Hydrocarbon Flow in a Pipeline Using CFD Simulation

Deepwater transportation of hydrocarbon reservoirs is commonly transported through subsea flowlines to surface processing facilities. During the transportation, the flowlines and the contents may be cooled to a deepwater temperature of 3ºC. Depending on the hydrocarbon fluids behavior and characteristics, this colder seabed may cause increased in viscosity and/or solidification of wax in the flowline. Severe wax deposition may lead to several problems in reduced production and impaired flow assurance which may eventually block the flowline. This problem will cause very high maintenance cost for cleaning work and could be very time consuming. Therefore, the subsea flowline temperature should be maintained above the Wax Appearance Temperature (WAT, 314K) by heat from an active heating system. The wax appearance temperature (WAT) is the temperature at which the crude oil first precipitates solid wax. This is possibly the single most important characteristic in examining wax deposition potential in crude oil. In this thermal management of active heating system, hot fluid such as water will circulate along the pipeline in a flow-loop to maintain the temperature and avoid solid depositions during both flowing and shut-down conditions.
The purpose of this project is to investigate the effect of thermal on the flow resisting properties of hydrocarbon flow in a pipeline using simulation. The simulation is performed using Computational Fluid Dynamic (CFD) simulation software (GAMBIT and FLUENT) to provide a pipeline bundle arrangement design that has the most effective heat transfer mechanism and has been validated with data generated from experimental activities.