Investigation and application of wellbore temperature and pressure field coupling with gas–liquid two-phase flowing

Abstract

With the development of gas well exploitation, the calculation of wellbore with single-phase state affected by single factor cannot meet the actual needs of engineering. We need to consider the simulation calculation of complex wellbore environment under the coupling of multiphase and multiple factors, so as to better serve the petroleum industry. In view of the problem that the commonly used temperature and pressure model can only be used for single-phase state under complex well conditions, and the error is large. Combined with the wellbore heat transfer mechanism and the calculation method of pipe flow pressure drop gradient, this study analyzes the shortcomings of Ramey model and Hassan & Kabir model through transient analysis. Based on the equations of mass conservation, momentum conservation and energy conservation, and considering the interaction between fluid physical parameters and temperature and pressure, the wellbore pressure coupling model of water-bearing gas well is established, and the Newton Raphael iterative method is used for MATLAB programming. On this basis, the relationship between tubing diameter, gas production, gas–water ratio, and wellbore temperature field and pressure field in high water-bearing gas wells is discussed. The results show that the wellbore temperature pressure coupling model of high water-bearing gas well considering the coupling of gas–liquid two-phase flow wellbore temperature pressure field has higher accuracy than Ramey model and Hassan & Kabir model, and the minimum coefficients of variation of each model are 0.022, 0.037 and 0.042, respectively. Therefore, the model in this study is highly consistent with the field measured data. Therefore, the findings of this study are helpful to better calculate the wellbore temperature and pressure parameters under complex well conditions.

Research on Downhole Throttling Characteristics of Gas Wells Based on Multi-Field and Multi-Phase

“…Zhang et al [18], based on thermodynamic theory, considered mechanical and hydraulic heat sources, solved the equations by the fully implicit finite difference method and matrix pursuit method, and proposed a calculation model of the drilling temperature and pressure field for shale gas horizontal wells. Zheng et al [19] combined the wellbore heat transfer mechanism and the calculation method of pipe flow pressure drop gradient through transient analysis by considering the interaction between fluid physical parameters and temperature and pressure. Thereby, they established a wellbore pressure coupling model for water-bearing gas wells and solved the problem that commonly used temperature and pressure models can only be used for single-phase states under complex well conditions.…”