Application of Genetic Algorithm in Optimization of Well Placement in Oil and Gas Reservoirs

Location, distance, placement, and number of wells are important factors in ultimate recovery from an oil or gas reservoir during a specific time interval. Well placement for new wells depends on numerous complex variables. Some of such variables are functions of time and hydrocarbon production. In addition, they are associated with large uncertainties and cannot be expressed by mathematical relations.Among all tools, numerical models can consider all interactions and dependencies of variables of the problem, therefore the best approach for calculation of well placement is numerical reservoir simulators. Although full-scale numerical simulator is the most accurate tool, but direct use of simulator is practically infeasible because the number of required simulation runs is very large. As an alternative, an optimization tool is required to be combined with numerical simulator.In this work, Genetic Algorithm (GA) has been used and investigated for optimization of well placement. A software was written for this purpose and Genetic Algorithm was embedded in it. The software can generate input model files for Eclipse reservoir simulator. We found that, if Genetic Algorithm is tuned carefully for desired problem, it will significantly reduce the number of required simulation runs.