Models estimate pressure losses in gas-condensate systems

The efficiency of currently available correlations for two-phase gas-condensate flows is undermined by the presence of water in these flow systems. Water radically modifies the pressure-loss mechanism. Five models have been developed for estimating the global pressure loss of such pipelines in actual operation. The results of these calculations are compared with field data contained in the American Gas Association's Multiphase Pipeline Data Bank which concerns different measurements relative to three lines of two-phase gas-condensate mixtures in the presence of water. The available correlations greatly underestimate pressure losses even if the water concentration is low compared to the entire liquid phase. In fact, the two-phase condensate-gas system becomes a three-phase water-condensate-gas flow in which the physical properties of liquid phases are quite different from each other.