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This study presents a comprehensive analytical modeling technology to model transient behaviors of multilayered reservoirs with inter-layer pure-planar crossflow induced by multi-stage hydraulically fractured horizontal well (MHFHW). The objective of this study is to develop an analytical model for multilayered reservoirs in conjunction with complex MHFHW and to achieve not only accurate and efficient computation, but also well-organized solutions expressed in a systematically integrated manner. The consideration of inter-layer crossflow across adjacent layers sets up the foundation for successful modeling of multilayered reservoirs. Source/sink function method (SSFM) is applied to describe fluid flow. Unsteady-state pressure or production rate solutions of MHFHW with the advantages of fast computation, accurate, and stable solutions are achieved. Comparative and consistent outcomes generated by this work and widely applied industry software have largely enhanced our technical confidence. More importantly, innovatively defined modified dimensionless terms that integrate systematic well-reservoir geometry information, as well as rock/fluid properties of each layer, have been newly applied to regulate the new modified dimensionless rate decline curve. This new technique sheds light on the reservoir characterization practice for complicated reservoir systems. Theoretical results in terms of transient pressure and rate were generated by the proposed multilayered model (SSFM-ML) for five scenarios of general concern, under various reservoir and well parameters, which were examined and discussed to demonstrate technical robustness. Not only does this study give solutions to the targeted multiple layered reservoirs, but it also provides insights into modeling three-dimensional fluid flow in heterogeneous reservoir with complex well configurations. It is recommended that future research should be conducted for more complicated two- and three-dimensional reservoirs, using the similar strategy of developing new type curves through adopting other new forms of modified dimensionless rate and time terms. [ABSTRACT FROM AUTHOR]

This paper presents an alternative semi-analytical model which is able to integrate PVT properties of gas with dynamic pressure domain during production process. A modified three-region radial composite model is developed to evaluate the gas condensate reservoir, taking account of different gas flow behaviors and pressure dependent properties, such as the compressibility factor. The governing equation of the pressure diffusion process is highly nonlinear due to the complex dependence of coefficients on pressure. The linearization of the non-linear partial differential equation describing the complicated gas flowing in a reservoir is handled by application of reasonable definitions of pseudo-pressure and pseudo-time for each region, which is integrated into the reservoir system through physical continuity of changing phases with PVT properties. Modified forms of total compressibility factor are proposed by valid theoretical developments. Results show that gas compositions of a gas condensate reservoir have significant effects on the fluid flow behaviors. Different proportions of C 5 , C 6 and C 7 + are simulated with constant makeup of C O 2 , N 2 and C 1 ∼ 4 , showing that small changes in composition of heavier components make distinct differences in the flow behaviors, as reflected on the liquids dropout curves. In addition, total compressibility factor varies with fluid compositions instead of remaining constant in a gas condensate reservoir. Through integrating PVT behaviors, the three-region model is able to accurately describe transient pressure behaviors of a production well in a gas condensate reservoir, which clearly characterizes three regions on the pressure derivative curves. A series of sensitivity studies are conducted to analyze the differences among the three regions. [ABSTRACT FROM AUTHOR]