FORMULATION AND EXPERIMENTAL VALIDATION OF A NEW EROSION FLOW MODEL

摘要

In the present work, a multivariable study has been conducted to systematically evaluate the effects of impact angle, material hardness, flow rate, sand concentration, particle size, and fluid viscosity on erosion. Experimental testing consisted of a submerged sand slurry jet impacting a flat plate in different orientations. Weight loss data, as well as profilometer surface scans have been collected on coupons to fully define the erosion. Empirical data trends were evaluated to provide insights into functional relationships between erosion rate and the parameters varied in the study. Interestingly, it was determined that scaling of experimental testing with regard to proppant concentration could be accomplished, since erosion rate normalized by the mass of sand impacting the eroded surface proved to be a constant. A total of five existing computational erosion models were evaluated against experimental data for both qualitative and quantitative performance. Results indicate that two models achieve relatively good comparison with experimental data without the need for case-specific tuning of model constants. This suggests that the use of these numerical models for erosion prediction in scenarios where tuning is not possible (due to lack of time/data), may still provide a reasonable estimate for the rate of material loss on equipment. As the culmination of experimental testing and computational benchmarking efforts, a new erosion model was also formulated. This model was based on both the experimental results and behavioral observations from existing submodels. The new model explicitly included contributions to erosion from the following variables: impact velocity, particle size, material hardness, and angle of impact. Improvement in simulated erosion rate agreement with empirical data was observed for all cases over existing submodels. However, those cases with higher particle diameters benefited the most. Using the new model, error compared to experiments was below 50% for all cases except one.