The vehicle system studied in this paper is a type of complex repairable system in which the subsystems follow various failure distributions and conform to arbitrary failure and repair distributions.The failure data o...The vehicle system studied in this paper is a type of complex repairable system in which the subsystems follow various failure distributions and conform to arbitrary failure and repair distributions.The failure data of subsystems are sometimes lacking,and the reliability test sample sizes tend to be small.Monte-Carlo technique combined with Bayes method is used to evaluate its dependability(reliability and maintainability).Following the "first-in,first-out" queuing rule,the logic relation of dependability is established by means of repairing priority and event lists.Simulation outputs the entire history of a mission,statistics of reliability and maintainability parameters and provides the basic data for system reliability design and maintainability management.展开更多
Basin simulation can quantitatively rebuild the histories of structural development,sedimentary en-tombment,thermal regime,hydrocarbon generation,migration and accumulation in time and space with 3D date.Thus the way ...Basin simulation can quantitatively rebuild the histories of structural development,sedimentary en-tombment,thermal regime,hydrocarbon generation,migration and accumulation in time and space with 3D date.Thus the way by which the hydrocarbon generated,migrated and accumulated can be recog-nized.展开更多
This paper investigates the deposition of asphaltenes in the porous medium of the studied field in Russia and predicts production profiles based on uncertainty evaluation. This problem can be solved by dynamic modelin...This paper investigates the deposition of asphaltenes in the porous medium of the studied field in Russia and predicts production profiles based on uncertainty evaluation. This problem can be solved by dynamic modeling, during which production profiles are estimated in two scenarios: with and without the activation of the asphaltene option. Calculations are carried out for two development scenarios: field operation under natural depletion and water injection into the aquifer as a reservoir pressure maintenance system. A full-scale compositional reservoir simulation model of the Russian oilfield was created. Within a dynamic simulation, the asphaltene option was activated and the asphaltene behavior in oil and porous medium was tuned according to our own special laboratory experiments. The model was also matched to production historical data, and a pattern model was prepared using the full-scale simulation model. Technological and the asphaltene option parameters were used in sensitivity and an uncertainty evaluation. Furthermore, probable production profiles within a forecast period were estimated. The sensitivity analysis of the pattern model to input parameters of the asphaltene option allowed determining the following heavy-hitters on the objective function: the molar weight of dissolved asphaltenes as a function of pressure, the asphaltene dissociation rate, the asphaltene adsorption coefficient and the critical velocity of oil movement in the reservoir. Under the natural depletion scenario, our simulations show a significant decrease in reservoir pressure and the formation of drawdown cones leading to asphaltene deposition in the bottom-hole area of production wells, decreasing their productivity. Water injection generally allows us to significantly reduce the volume of asphaltene phase transitions and has a positive effect on cumulative oil production. Injecting water into aquifer can keep the formation pressure long above the pressure for asphaltene precipitation, preventing the asphaltene deposition resulted from interaction of oil and water, so this way has higher oil production.展开更多
基金Sponsored by National Post Doctor Science Foundation of China (2003033180)
文摘The vehicle system studied in this paper is a type of complex repairable system in which the subsystems follow various failure distributions and conform to arbitrary failure and repair distributions.The failure data of subsystems are sometimes lacking,and the reliability test sample sizes tend to be small.Monte-Carlo technique combined with Bayes method is used to evaluate its dependability(reliability and maintainability).Following the "first-in,first-out" queuing rule,the logic relation of dependability is established by means of repairing priority and event lists.Simulation outputs the entire history of a mission,statistics of reliability and maintainability parameters and provides the basic data for system reliability design and maintainability management.
文摘Basin simulation can quantitatively rebuild the histories of structural development,sedimentary en-tombment,thermal regime,hydrocarbon generation,migration and accumulation in time and space with 3D date.Thus the way by which the hydrocarbon generated,migrated and accumulated can be recog-nized.
文摘This paper investigates the deposition of asphaltenes in the porous medium of the studied field in Russia and predicts production profiles based on uncertainty evaluation. This problem can be solved by dynamic modeling, during which production profiles are estimated in two scenarios: with and without the activation of the asphaltene option. Calculations are carried out for two development scenarios: field operation under natural depletion and water injection into the aquifer as a reservoir pressure maintenance system. A full-scale compositional reservoir simulation model of the Russian oilfield was created. Within a dynamic simulation, the asphaltene option was activated and the asphaltene behavior in oil and porous medium was tuned according to our own special laboratory experiments. The model was also matched to production historical data, and a pattern model was prepared using the full-scale simulation model. Technological and the asphaltene option parameters were used in sensitivity and an uncertainty evaluation. Furthermore, probable production profiles within a forecast period were estimated. The sensitivity analysis of the pattern model to input parameters of the asphaltene option allowed determining the following heavy-hitters on the objective function: the molar weight of dissolved asphaltenes as a function of pressure, the asphaltene dissociation rate, the asphaltene adsorption coefficient and the critical velocity of oil movement in the reservoir. Under the natural depletion scenario, our simulations show a significant decrease in reservoir pressure and the formation of drawdown cones leading to asphaltene deposition in the bottom-hole area of production wells, decreasing their productivity. Water injection generally allows us to significantly reduce the volume of asphaltene phase transitions and has a positive effect on cumulative oil production. Injecting water into aquifer can keep the formation pressure long above the pressure for asphaltene precipitation, preventing the asphaltene deposition resulted from interaction of oil and water, so this way has higher oil production.
