The article presents an analysis of the results of the calculation of downhole pressure in the trunk of a producing well according to various models of multiphase flow (No Slip, Hasan – Kabir, Beggs – Brill, Ansari, Zhang, Orkiszewski). We compared results of numerical calculations with similar models presented in Saphir and PipeSim software; we used the same set of PVT correlations for the extracted fluids properties. Test cases included various values of parameters such as the gas factor, the diameter and angle of the borehole, water cut, and fluid flow for the design area from 100 m to 3000 m. This approach allowed to test the models under consideration in all possible modes of multiphase flow. The comparison results showed good convergence. The models were also tested on Y field data obtained during hydrodynamic studies at mechanized production wells. It is established that the success of pressure forecasting by one or another calculation method mainly depends on taking into account the following parameters: the geometry of the wellbore, changes in the properties of the extracted fluids, the structure of the multiphase flow and the dynamic flow pattern in the wellbore. The analysis of the obtained results showed that it is possible to distinguish several models of multiphase flow that will be most applicable in terms of the accuracy of downhole pressure prediction. In particular, for the considered Y field, it was revealed that such models as Beggs – Brill, Hasan – Kabir, Orkiszewski can be recommended in the wells under consideration. It is also shown that, for example, the Hasan – Kabir mechanistic-empirical model should be modified for different well conditions. This can be done by selecting empirical parameters that characterize the dynamics and structure of the flow for the corresponding properties of fluids and modes of multiphase flow in the wellbore. This will allow to correctly apply the methodology and more accurately predict the bottom-hole pressure during well operation. All created calculation modules of the presented algorithms are included in the corporate software package RN-VEGA for the interpretation of hydrodynamic studies of wells.
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