Analysis of gas well late-time pressure and rate data

Ding, W., Onur, M. and Reynolds, A.C., 1990. Analysis of gas well late-time pressure and rate data. J. Pet. Sci. Eng., 4: 293-307. This work presents new methods for estimating average pressure, reservoir pore volume (initial gas in place) and drainage area from pressure and rate data obtained at a gas well during boundary-dominated flow. The methods, which utilize a combination of a material balance equation and approximations for the wellbore pseudopressure or flow rate obtained during boundary-dominated flow, represent an improvement over previous methods in that the new methods are direct procedures which do not require iteration.