Description And Token Of The Evolutionary Process Of Dynamic Reservoir Systems

The reservoir is a system buried deep under the ground. The one flooded by water or chemical agents is an open, complex and dynamic reservoir system far away from equilibrium. Its dynamic evolutionary process embodies the multi-level regularity. As a famous random theory, the Markov process is very good in exactitude and flexible in adaptation, which is applicable to the description of the dynamic reservoir system with randomicity and complexity.In the dynamic reservoir system, the distribution of pores and channels is random and complex. When the fluid is injected to displace the crude oil, the concentration difference between the injected solution and the in-site fluid makes the movement of particles in solution the common results of both molecular diffusion and convectional dispersion. Experiments show that the dispersivity increases with the average diameter of particles in solution. In the period of flooded agent flowing through the dispersion area, the transition between states of particles'locations is a Markov Process without aftereffect, of which the transition probability can be described by the Chapman-Kolmogroff equation. Based on its differential form, the Fokker-Planck equation is obtained by simplification. Then on the physical model of sand packing with circular tubes, the diffusion-dispersion equation is deduced considering the effect of particles adsorption. Also, the concentration distributions of the suspending liquid are solved by the method of Numerical analysis for different cases such as in the finite reservoir, the semi-infinite reservoir and the core with limited length. And the effect of the dimensionless dispersivity on the extent of the diffusion-dispersion is analyzed detailedly.Between the reservoir system and the external environment the constant material exchange makes the dynamic reservoir system more complex. Since the traditional modeling method can't describe the evolutionary processes of transition between states from micro to macro in the complex dynamic system, a creative idea is required to guide the construction of a new modeling in accordance with the changes.It is objective that injection decline in the process of reservoir development. In this paper a combined model is used to predict the extent of injectivity decline including both diffusion-dispersion model with particle adsorption and the outer mud cake formation model. The results show that the bigger the particles and the smaller the porosity, the larger the formation damage. In order to provide reference for production decision the paper takes the increment change of crude oil production as a foundation and predicts the crude oil production by using Markov Chain.There is disciplinarian in the transfer of substance and energy between a dynamic system and its external environment. The complexity of the dynamic system and multiformity of the objectives make the main body that makes choices face the conflicting circumstances frequently. So it is helpful for decision makers to make better decisions if they get a clear understanding of the environment and conflicting types. The traditional Expected Utility Theory for economic choice cannot explain some phenomena in the dynamic system. The Sigmoid curve in the Expectation Theory of Behavioral Economics can explain the phenomena that decision-makers are more sensitive in face of loss than of benefit. The decision for the dynamic reservoir system is the same problem as any other complex system, and follows the same choosing law.