Title: A New Approach for Predicting Frictional Pressure Losses of Non-Newtonian Fluids in Coiled Tubing
Author(s): B. Medjani, Sonatrach, Algeria, and S.N. Shah, The University of Oklahoma, Norman, Oklahoma, USA
Presentation: 2000 SPE Rocky Mountain Regional/Low Permeability Reservoirs Symposium
Location: Denver, Colorado
Date: March 12-15, 2000
Abstract: The importance of the pressure loss in the design of treatments for various field applications while using non-Newtonian fluids necessitates the estimation of the pressure loss in the reeled part of the coiled tubing unit. The present work discusses the analysis of frictional pressure loss of non-Newtonian fluids flowing through coiled tubing and includes the effects of fluid concentration and the influence of coiled tubing curvature and length. An experimental investigation of three polymeric solutions is conducted to predict the frictional pressure losses related to their flow behavior in coiled tubing. A total of 1500 ft of 1-in., 5000 ft of 1 1/2-in. and 3000 ft of 2 3/8-in. coiled tubing was used for this purpose. Also, straight sections of coiled tubing were employed for obtaining frictional losses in straight sections, which then are compared with those of reeled coiled tubing. Experimental results are also compared with the correlations presented earlier by Srinivasan for Newtonian fluids and McCann for non-Newtonian fluids. From the data analysis, it was found necessary to develop a new model which includes Dean number. The Dean number takes into account the curvature effect. This new model is proposed for the prediction of the friction factor in coiled tubing for fluids exhibiting power law pseudoplastic type behavior with flow behavior index less than unity.