A strategy for simulation and optimization of gas and oil production

A new formulation to easy simulation and optimization of gas and oil production systems is presented in this work. The problem of interest corresponds to the typical daily gas and oil production calculation, i.e. a one-day time period planning. The simulation problem considers determination of oil and gas production for the current topology. The optimization problem is established by considering that the instantaneous production of the gas/oil network must optimally satisfy a given demand. Non-linear behavior and reverse flow is assumed for wells and cubic equations of state are used to estimate thermodynamic properties. The resulting model contains differential and algebraic equations for a given fixed topology of interconnected wells coupled with surface pipeline networks. The model combines DASSL to solve the inner set of differential–algebraic equations, and Knitro to solve both the optimization problem and the overall set of non-linear equations. The good performance of the model and the numerical strategy is illustrated with real cases of study.