Mathematical Modeling of the Process of Steam-Assisted Gravity Drainage during the Extraction of High-Viscosity Oil

The paper is devoted to the development of models and methods to describe and predict the process of steam-assisted gravity drainage during the extraction of high-viscosity oil. On the basis of the original physicomathematical model, the authors have considered the problems of circulation of a steam in the injection well for preheating the stratum, the stratum sweep by the action of the steam, and methods to increase it. The presence of the optimum spacing between pairs of reactive wells or the optimum density of the network of wells has been established. From an analysis of basic mechanisms of the process, the authors have identified the causes of the maximum value of the oil recovery factor for the optimum network of wells. The possibility has been shown of raising the economic efficiency of the process of passage from the injection of a steam to the injection of unheated water in the final stage of the process.