The design of high-viscosity oil reservoir model based on the inverse problem solution

We propose an approach to the solution of the automatic history-matching problem for constructing models of high-viscosity oil reservoirs. It is based on a special parameterization of the reservoir model with the use of not only the physical but also the geometric parameters and minimization of the functional of residual between observed and computed data of cumulative oil production, bottomhole pressure, oil rate, water and oil cut. In order to obtain physically reasonable values of parameters and reduce the number of iterations when solving the inverse problem, the adaptive regularization is used. We use the finite element method on non-conforming meshes with hexahedral cells to solve the forward problem. The forward problem solution is verified by comparison with the results presented in the 10th SPE Comparative Solution Project. The applicability and effectiveness of the proposed approach are demonstrated on the simulated and real field data obtained on the site of one of the high-viscosity oil fields. Using the simulated data obtained for the complex realistic petroleum reservoir model, we show that the proposed approach allows us to obtain distributions of absolute permeability, porosity, and oil in the reservoir volume as well as to estimate oil reserves and their changes with time. The results of numerical experiments performed using the real field data show that the approach proposed for the history-matching problem solution enables us to make reliable production forecasts. In the forecast period, the deviations of the predicted total oil production from the observed one do not exceed 1.5%. •The high-viscosity oil reservoir model is constructed using real field data.•The history-matched reservoir model allows obtaining a reliable production forecast.•The history-matched reservoir model reflects adequately the initial oil reserves.•The history-matched reservoir model reflects adequately oil reserve changes with time.