Abstract
Abrasion-corrosion wear rates in horizontal pipeline slurry flow were modelled using novel semi-empirical and numerical approaches. The numerical approach, computational fluid dynamic (CFD) was only used to model abrasive wear. The abrasive wear model that came with the CFD software was also used. The novel semi-empirical approach adopts several existing models to predict abrasion-corrosion wear rates. The objective of the study was to assess a simple tool that can be used to identify risk, perform “what-if-scenarios” and/or pipeline system optimization, especially situations where there is no accurate measured or computed local flow parameters available. Predicted results were compared with previously acquired hydrodynamic and wear data in our pilot-scale slurry flow loop for both mild steel and dual-phase stainless steel pipe spools. Slurry consisted of sand mixed with municipal water. The study was done in a 193.7 mm (7.625 in) horizontal pipe with mixture velocity of 4.5 and 7 m/s at solids concentration of about 20 v/v% and dissolved oxygen concentration of 1.0 ppm. Our proposed novel modeling approach results were found to be in reasonable agreement with measured data, and can easily be integrated with existing hydrodynamic models or tools. However, further improvement maybe required if quantitative accuracy is needed. The abrasive model that came with CFD software package fails to predict both wear pattern and magnitude. It seems to be somewhat inversely correlated with wall shear stress which is contrary to measured data. Also, CFD fails to predict expected solids velocity profile in stratified or slurry flow with moving bed. Further investigation is required for this flow regime.
