The analysis of alternatives of development of gas deposits and condensed is usually carried out by using the coupling between the balance of materials in predictive mode and the nodal analysis or also using numerical simulation models. In both cases it is required a suitable model of the multiphase flow behavior in vertical pipes in order to be able to predict with accuracy the flowrates the wells will produce through the different life stages of the reservoir. The correlations for the multiphase flow, with which it is modeled the flow in vertical tubes, show a big dispersion of results in flowrates less than 50 km3std/d with gas – liquid relationships less than 10000 m3/m3. This area of low flowrates and low gas – liquid relationships is usually observed in the gas and condensed reservoirs final phase due to the decline in the production because of the fall of the static pressure and the fall of the gas – liquid relationship and the increase of the water cut. Consequently, the dispersion in the correlations generates important differences in the production forecasts, with the associated high economic impact, because the pressures for abandonment of the wells are very different according to the multiphase correlation used. In this work we show an exhaustive statistical analysis of the behavior of the multiphase flow correlations in vertical tubes, contrasted with measurements of pressure gradients in wells, in the majority of the cases within the ranges of flowrates and gas – liquid relationships mentioned in the previous paragraph. From the results of this analysis, it is developed a new correlation of multiphase flow for gas – condensed – water systems that allows predicting the pressure gradients in vertical tubes within the reasonable error ranges. We show the methodology used for the development of the correlation and the statistical analysis of the results of the application of it based on the data from the studied cases.
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