Research Of Numerical Simulation On The Change Of Reservoir Parameters During Flood Development

Both old oilfield coring data in high water cut stage and mines dynamic logging data show that reservoir permeability, crude oil viscosity and rock wettability have changed greatly after long-term flood development compared with the early. But the change of these parameters is not considered in existing reservoir numerical simulation software. It's innconsistent with the actual oilfield development and will cause prediction results of poor accuracy which have big deviation to actual results. Therefore, it has vital significance to clear the distribution of remaining oil in high water cut stage to guide further oilfield development and enhance oil recovery in the increasingly tense situation of oil and gas resources cullently, which bases on establishment dynamic geological model conforming to the actual situation of the underground for fine reservoir numerical simulation after systematic and comprehensive research on reservoir parameters change rules due to development factors.The effect of injection water power function on parameters change has been focused on in this paper. After that, parameters time-varying description models are established on the basis of the relationship between reservoir parameters change and flood water pore volume multiple and introduced in the mathematical model used in conventional three-dimensional and three-phase black oil model. Using finite difference methods, the mathematical model is discretized to numerical model, The numerical model is soluted by IMPES method. At last, Parameter time-variance numerical simulation software is compiled by using FORTRAN 90 and Visual C++ program languages. This software makes up for the current commercial reservoir numerical simulator and improves the precision of the reservoir numerical simulation.Research shows that the change of reservoir parameters has significant effects on the flood development effect: the increase of reservoir permeability and crude oil viscosity causes water flooding development to become worse; the rock wettability change generates a better effect.