Abstract: Numerical simulation as an effective method for determination of recovery of oil-gas reservoirs has been widely used to evaluatethe effects of different development schemes on the ultimate recovery of reservoirs with different types, different crude oil andpetrophysical properties. However, this method is scarcely used to estimate the recovery of a gas reservoir. Usually, formula method, gasreservoir driving type method and analogy method, etc., are used to determine the abandonment pressure or recovery. This paper, bymeans of numerical simulation study, evaluates the sensitivities of different factors affecting the abandonment pressure and recovery of agas reservoir in western Sichuan.

Key words: gas reservoir, abandonment pressure, recovery, numerical simulation