Simulating Filtration to Evaluate Hydrodynamic Indices of the Underground Gas Storage Operation

Abstract

The research objective is to develop and test mathematical model of gas storage in the layered aquifer with poorly permeable interlayer if plane-parallel and axisymmetric filtration takes place. The paper evaluates the gas-hydrodynamic operational indices of the underground gas storages within aquifers in the South East Ukraine. Comprehensive approach has been applied involving collection, systematization, and analysis of actual data on filtration and physicomechanical properties of enclosing rocks impacting formation of natural and technogenic deposits as well as analytical and numerical methods to solve equations of the gas-water contact shift under different conditions. A gas-hydrodynamic model of underground gas storage within the nonuniform aquifer has been substantiated to calculate its cyclic operation in the three-layered seam taking into consideration crossflows through a poorly permeable stopping. The calculation results show significant impact of characteristics of the layered porous environment on the gas water contact transfer through certain seams. The derived new technique linearizing a system of differential equations to identify pressure within a reservoir is generalization of the earlier applied procedures with introduction of ‘boundary schemes’. The calculation results demonstrate significant impact of the layered porous environment on the gas water contact transfer through certain seams. The findings may be applied while making evaluations at the stage of gas storage design within aquifers.