Some Applications Of Optimization And Control Theory In Petroleum

Based on modern optimization theory and optimal control theory, this dissertation studies some questions as follows:1. The optimization model of parameter identification of three-dimensional geologic history numerical simulation, algorithm and its applicationGeologic history numerical simulation is a basic content of basin numerical simulation, and the porosity is the major parameter in the evolution and development process of oil-bearing basin. According to the sedimentation and burial mechanism, the physical and chemical principles of oil geology, the mudstone porosity's non-linear parabolic partial differential equation has been established. The initial and dynamic boundary conditions are dealt and the solution's existence and uniqueness of the equation is proved too. Then the optimization model of parameter identification of the distributed parameter system for three-dimensional geologic history numerical simulation is constructed, and the objective function is the stratum data from the practical measuring. According to the Domain Decomposition Methods, the piecewise smoothness and the specialties of geologic history, the optimization model is decomposed, therefore backstripping-forwardburying method which is simple and efficient in a way is constructed. The model and the algorithm are successfully applied in Xiaocaohu topographic depression in Turpan-Hami basin. The numerical results show that the model is correct and has good applicability, and the calculated amount is acceptable. At last, based on the results of geologic history numerical simulation and the force and substance balance theories of deep basin gas, the dynamic procedure of the entrapment forming of reservoir, the characteristics of generation and discharge gas of the source rocks and the coupling relations between the two are studied, so the distribution and the reserves of deep basin gas at specific geologic times have been obtained.2. The optimal strategies for exploration and extraction of oil and gas resourcesThe oil and gas resources are the scarce, strategic and exhausted resources, so the development strategies for the exploration and extraction should be made scientifically. The problem has been studied from two sides, firstly, from the viewpoint of applicability, based on the development strategic objectives of the oil company, with the aim to unify the exploration and extraction decisions of the resources in an integrated framework, and integrate the macro economic and technical objectives with micro economic and technical models of an oil well, an integrated non-linear dynamic optimal control model has been constructed, the objective is the benefit maximum of the exploration and extraction of the resources, and the optimalstrategies are obtained by changing the problem into a non-linear mathematical programming problem, on the other hand, from the more macro level, based on the analysis of the characteristics of the exploration and extraction activities of oil and gas resources, a conclusion is easily deduced that the procedure is full of randomicity, then discovering procedure of oil deposit is proved to be a Poisson process, and the reserves process is a supermartingale process, so the model of exploration discovery rate and the reserves model could be constructed. Certainly, with the objective to maximize the income of development of the oil and gas, an stochastic optimal control model for the exploration and extraction of oil and gas resources has been established, under the assumption that price of oil and gas follows the geometric Brownian motion. Finally, the HJB equation of the value function has been obtained by the dynamic programming method, then by the analysis of equation and economic meanings of the equation and the variables, optimal strategies can be found.3. The value evaluation of exploration innovation technologies based on output-growth production function & DEA methodWith the fast development of the modern science and technology, technology and technology innovation have play a key...