An Optimization-Based Method for the Explicit Production Data Analysis of Gas Wells

This work aims at the exploration of production data analysis (PDA) methods without iterations. It can overcome limitations advanced type curve relying on iterative calculation material-balance pseudotime and current explicit reckoning specific schedule assumptions. The dynamic material balance equation (DMBE) is strictly proved by integral variable substitution based gas flow under boundary dominated (BDF) condition static (SMBE) a reservoir. We introduce pseudopressure level function γ ( p ) recovery factor R to rewrite DMBE in terms observed Y estimated e ; then PDA be transformed into an optimization problem minimizing error between . An optimization-based method for wells (OBM-EPDA), therefore, developed paper, capable determining BDF constant reserves explicitly accurately rate and/or flowing pressure systems. Three stimulated cases demonstrate applicability validity OBM-EPDA with small errors less than 1% values both Not second previous studies, field case further proves its practicability. shown that nonlinear relation represented polynomial merely dependent inherent properties system even before sorting out data. provided facilitate quality control, elimination outliers not subject improves reliability analysis. For various systems producing whether rate, bottomhole (BHP), or BHP conditions, proposed gives insights well-controlled volume capacity well low-pressure high-pressure reservoir, where compressibilities rock bound water are considered.