Gasohydrodynamic Testing of Gas and Gas-Condensate Reservoirs and Wells

Abstract

The article outlines the steady-state gasohydrodynamic methods used for testing gas and gas-condensate reservoirs and wells. To select downhole equipment for wells characterized by abnormally high reservoir pressure, indicator diagrams were constructed in the form of curved lines. As a result of these studies, all reservoir and well parameters, including optimal flow rates, drawdowns, allowable dynamic bottomhole pressures, the amount of mechanical impurities, reservoir pressure and temperature, were determined. A two-term inflow equation was used, and the coefficients a and b were determined graphically. In addition, formulas for calculating these coefficients for hydrodynamically complete (perfect) wells are provided. For hydrodynamically incomplete (imperfect) wells, formulas for the incompleteness coefficients C₁, C₂, C₃, and Cₙ, as well as for the inflow equation parameters a and b, are presented. The values of these coefficients and parameters were also determined using numerical methods, and the corresponding formulas are provided. The indicator diagrams, i.e., the curves showing the dependence of gas flow rates on dynamic bottomhole pressures, were linearized, and the parameters a and b of the inflow equation were determined graphically. The indicator curves pass through the origin, are concave with respect to the flow-rate (abscissa) axis, and represent monotonically increasing functional relationships.