Comparison of Computational Fluid Dynamics of Erosion in Coiled Tubing on Various Wrap Diameters

Abstract

Abstract Coiled tubing (CT) is widely used in well intervention as a practical and cost-effective means of servicing wells. Since CT's inception, the actual flow through CT has been a point of discussion and theory. Testing has been conducted to study what occurs inside the CT. In recent years, the use of computational fluid dynamics (CFD) software has provided greater insight into actual CT flow patterns, including fluid-flow velocity profiles and secondary flow regimes. CFD helps to understand the fluid-flow phenomenon, which leads to effective application of friction-loss gradients. CFD has proven to be an effective alternative to full-scale testing. This work compares the results of CFD modeling of internal erosion caused by proppant to actual field data. This paper investigates the increased erosion rates found in the area of tubing that is on the tubing reel during pumping operations. Specifically this paper will investigate how the wrap diameter influences erosion rates as indicated in field data. It compares predicted values, actual values, and computed values from CFD analyses. Results from this work and previous work can be used to correlate a predictive model of erosion rates that can be applied to correct wall-thickness values used in bending fatigue models and force limit calculations. CFD was used to provide correlations for the predictive model without full-scale testing, which greatly reduced the cost of development. Fluids investigated include slurry pumped from an actual job.