AIC Applications in Coiled Tubing Hydraulics

Coiled tubing (CT) has been used in well drilling, completion, stimulation, wellbore cleanout, and other operations in the petroleum industry where various fluids are pumped under turbulent flow conditions. Accurate estimation of frictional pressure losses when pumping these fluids through coiled tubing has remained a challenge and a milestone for job success. This challenge has triggered the research activities in the field of coiled tubing hydraulics. As a result, there have been extensive studies on flow of Newtonian fluids in coiled tubing and several equations have been published to calculate the Fanning friction factor. Each of which has its own applications and limitations. Applications of these equations without verification may lead to erroneous results, and eventually job failure. Employing the new Akaike Information Criteria or AIC theory, the authors compared and questioned the applicability of these correlations to propose the most accurate one. This study employs the R^2 method and the Information Theory Approach in selecting the best model to predict the Fanning friction factor. It shows that among six different models, the best model to predict the Fanning friction factor is McCann and Islas model and the weakest one is Mashelkar and Devarajan model. A comparison between R^2 and AIC theory is also presented to show the advantages of AIC theory over R^2 method. In conclusion, the authors are introducing a new theory to the oil and gas industry where they believe that employing this theory can resolve various difficulties faced by the researchers in the oil field. This paper represents the first application of AIC theory in the oil and gas theory and helps advances the state-of-the-art in this field.