| Given a reservoir containing hydrocarbons, with dimensions and properties defined completely for reservoir and fluids; the problem is to maximize the present value of hydrocarbons removed from the reservoir through its economic life, by choice of the completion- and production-policy to be used during the economic life of wells drilled in that reservoir. It is subject to constraints of production and boundary conditions for the reservoir.;Both models are combined in a general algorithm of solution proposed to solve the optimization problem, and a computer code was developed and tested in the CDC-CYBER 170/750 computer installed at The University of Texas at Austin. This computer code was used in the solution of more than 300 different problems involving four different types of reservoir, and the results were used in a sensitivity analysis on the effect of different parameters in the behavior of the objective function used in this study.;We observe that the optimal completion- and production-policy to be used in a well are dependent on the reservoir type where it is completed, and they are different from each value of parameters describing the system (reservoir-fluid-well-economic). The model can be used to determine those policies for each new well to be completed in a reservoir.;The problem is solved in two stages. First, a three-phases semianalytic single well model is formulated in order to determine the reservoir response to any completion- and production-policy. This model assumes that the cone of water and gas can be represented as a succession of steady-states. Second, an optimization model based in the discrete version of the Maximum Principle of Pontryagin, and the Fibonacci search method is formulated to determine the optimal production- and completion-policy that will be used through the economic life of the wells. |
