The Prediction of Pressure Loss During Two-Phase Horizontal Flow in Two-Inch Pipe

This investigation of multiphase flow, supported jointly by the Texas Petroleum Research Committee, The University of Texas, and many companies affiliated with the oil industry, is an effort to develop a reliable method of predicting static pressure loss during two-phase horizontal flow in 2-in. pipe. The 165 two-phase tests were run in 1688 ft of 2-in. steel line pipe with water, distillate, and crude oil in connection with natural gas. The liquid flow rate ranged from 50 to 2500 B/D, with gas rates up to 6 MMscf/D. The range of mean line pressures was from 70 to 850 psig. Pressures were measured at 12 line locations, the liquid holdup was measured at two locations, and flow patterns were photographed through plastic pipe sections. From the data, correlations have been developed for liquid holdup and for an energy loss factor. The correlations can be used in conjunction with a derived equation to predict two-phase horizontal pressure losses. The prediction method is carefully outlined and, although it lends itself to computer usage, it is relatively fast and just as accurate by hand. Applied to the original data, the method yielded pressure gradients with an average error of 2.3 percent.