Experimental and simulation studies of the effect of surface roughness on corrosion behaviour of X65 carbon steel under intermittent oil/water wetting

The effect of surface roughness on corrosion behaviour of carbon steel under intermittent oil/water wetting with different flow conditions was investigated by an “alternate wetting cell”, combining with potentiostatic polarisation, contact angle measurement, and computational fluidic dynamics (CFD) analysis. Under static flow conditions, the rough surface increased the oil film lifetime and consequently mitigated the corrosion as the oil film has good adhesion and acted as a blocking barrier. However, under dynamic flow conditions, the smooth surface polished by 6 Micron diamond suspension shows the longest oil film lifetime and highest corrosion mitigation efficiency, caused by small turbulence eddies and low shear stress.