Abstract
This paper reports the process and conclusions of computational fluid dynamics (CFD) modelling performed to understand and evaluate the events taking place within the novel rotating coupon erosion-corrosion test apparatus.
The test method utilises a rotating coupon being spun at high speed in a high weight % sand slurry for a fixed duration. Under specific conditions the phenomenon of erosion-corrosion is studied. For this to happen impingement of the sand on the test specimen is required. The CFD modelling has evaluated the system to allow for sand concentrations and impingement rates at the rotating coupon’s surface to be approximated.
The computational model has been constructed and solved using a commercial numerical toolkit. The model resolves the hydrodynamics of the system including the effect of turbulence and accounts for the relative motion of the sand through the algebraic slip model. Algebraic slip accounts for the differential velocities of the primary and secondary components, but uses a single velocity vector that represents the mixture averaged velocity to make conclusions. The outputs from the model include concentration profiles, flow patterns, particle distribution and impingement rates.
In combination with the observed test method baselines and performance of corrosion inhibitors, it is possible to develop a hypothesis on the occurrences in the test and the mode of action that the inhibitors function by.