Nowadays, the intermittent mode is becoming one of the best ways to operate low-rate ESP wells due to its efficiency especially at the late stages of reservoir development. However, it is essential to know how to determine the best work parameters for the periodic mode to make use of its full potential. So, there is a need for complex algorithms which can be applied to handling both problems – intermittent well model creation and optimal work parameters search. The physically driven mathematical model was designed which represents a system of three key elements: “tubing – annulus – drainage area”. They are connected with each other through boundary conditions defined in the ESP intake by mass conservation equations. The optimization task can be split into two blocks. The first stage, adjusting the model to the real operational data to match calculated dynamics, is handled by introducing “adaptation” parameters which represent specifics of a certain tubing system and varying IPR curve. During the second stage, optimization itself is implemented by various optimization-aimed algorithms which objective is maximizing income while following operational and geological constraints. The results of the work are following: the model of the intermittent ESP well; a software library built around the created model for calculating the dynamics of the parameters and the production performance of wells operating in intermittent mode; complex algorithms for well model adaptation and optimization of periodic operation mode. Quality assessment of the developed model was carried out by analyzing the convergence with numerical solutions obtained using commercial software designed for numerical modeling of non-stationary multiphase filtration in pipelines. The created model showed good convergence with well-trusted commercial software. The paper also provides the results of modeling and the predictive ability of adaptation and optimization approaches on real cases from pilot fields.
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