Abstract
Friction losses for foam fluids in coiled tubing are not the same as that of in straight tubing. The flow properties of the foam are also very different than that of conventional two-phase fluids7 . Factors like foam quality, liquid phase viscosity, flow rate, gel concentration, temperature, and curvature of pipe strongly affect the frictional behavior of foam fluids. The present work discusses and analyges friction pressure losses and rheology, and friction loss correlation development for guar based foam fluids through coiled tubing.
The present study investigates frictional pressure losses in coiled tubing for polymer based foam fluids. The experiments are conducted using guar gel and guar foam employing a pipe flow viscometer at 1000 psig. Foams are prepared and tested for qualities 0 to 80 % at various shear rates using temperatures from 100 to 200 °F. Three polymeric foam solutions are examined for their frictional pressure losses related to their flow behavior in coiled tubing.
The experimental data of differential pressure drop and flow rate converted to Fanning friction factor and Reynolds numbers respectively are used to obtain new empirical correlations to predict Fanning friction factors. These empirical friction loss correlations are function of foam liquid phase properties and curved geometry, and are applicable for the range of shear rates investigated. Significant increase in friction pressure loss is observed in coiled tubing compared to that in straight tubing. Empirical friction loss correlations can be used to predict an accurate Fanning friction factor for foam fluids in coiled tubing.
