Nonlinear flow and well test analysis in porous media

Based on the analysis of factors influencing fluid infiltration in porous
media, this book systematically summarizes the characteristics and expressions
of low-velocity nonlinear flow and high-velocity nonlinear flow infiltration
in porous media and provides a set of evaluation methods. Using the
exponential formula, the starting pressure gradient formula, and the binomial
equation of motion, the authors present a detailed comparison and analysis of
the production, pressure, and dimensionless background pressure of the
nonlinear flow and Darcy linear flow for steady and unsteady flow. In
addition, based on the equation of motion of the starting pressure gradient, a
mathematical model of the one-, two-, and three-medium nonlinear seepage flow
is established, and approximate analytical solutions are given while the graph
of the corresponding well test curve is drawn. Finally, based on the
mathematical model of the well test established from the exponential equation
of the high-velocity nonlinear flow motion, the atypical well test curve and
the relational surface of the time- and space-varying infiltration index are
obtained. The authors also discuss the relationship between reservoir and
fluid properties and the nonlinear flow test curve. This book is intended to
serve as a reference for technical personnel, researchers, teachers, and
students involved in oil and gas development. Its research contents provide a
theoretical basis for the identification of water flow dominant channels in
the long-term water injection development of high-water-cut oilfields, profile
control and water shut-off, productivity evaluation of carbonate reservoirs
and formation parameters.