This paper deals with a class of nonlinear boundary value problems which appears in the study of models of flows through porous media. Existence results of asymptotic bifurcation and continua are reported both for ope...This paper deals with a class of nonlinear boundary value problems which appears in the study of models of flows through porous media. Existence results of asymptotic bifurcation and continua are reported both for operator equations and for boundary value problems.展开更多
Theoretical equations for computing sensitivity coefficients of wellbore pressures to estimate the reservoir parameters in low-permeability reservoirs conditioning to non-Darcy flow data at low velocity were obtained....Theoretical equations for computing sensitivity coefficients of wellbore pressures to estimate the reservoir parameters in low-permeability reservoirs conditioning to non-Darcy flow data at low velocity were obtained. It is shown by a lot of numerical calculations that the wellbore pressures are much more sensitive to permeability very near the well than to permeability a few gridblocks away from the well. When an initial pressure gradient existent sensitivity coefficients in the region are closer to the active well than to the observation well. Sensitivity coefficients of observation well at the line between the active well and the observation well are influenced greatly by the initial pressure gradient.展开更多
During the development of low permeability reservoirs. the interaction between fluid flow and rock mass deformation is obvious. On the basis of fluid mechanics in porous media and elasto plastic theory. the author p...During the development of low permeability reservoirs. the interaction between fluid flow and rock mass deformation is obvious. On the basis of fluid mechanics in porous media and elasto plastic theory. the author presents an equivalent continuum model to simulate fluid flow in fractured low permeability oil reservoir coupled with geo stress. The model not only reflects the porosity change of matrix, but also the permeability change due to the opening and closing of fracture. By analyzing of simulation results, the changes in porosity and permeability and their effect on oil development are studied.展开更多
The authors investigate the sensitivity of hydrostatic pressure of flows through porous media with respect to the position of the soil layers. Indeed, these induce discontinuities of the porosity which is a piecewise ...The authors investigate the sensitivity of hydrostatic pressure of flows through porous media with respect to the position of the soil layers. Indeed, these induce discontinuities of the porosity which is a piecewise constant coefficient K of the partial differential equation satisfied by the pressure u and it leads to the computation of the derivative of u with respect to changes in position of discontinuity surface of K.The analysis relies on a mixed formulation of the problem. Preliminary numerical simulations are given to illustrate the theory. An application to a simple inverse problem is also given.展开更多
Lattice-Boltzmann(LB)simulations are a common tool to numerically estimate the permeability of porous media.For valuable results,the porous structure has to be well resolved resulting in a large computational effort a...Lattice-Boltzmann(LB)simulations are a common tool to numerically estimate the permeability of porous media.For valuable results,the porous structure has to be well resolved resulting in a large computational effort as well as high memory demands.In order to estimate the permeability of realistic samples,it is of importance to not only implement very efficient codes,but also to choose the most appropriate simulation setup to achieve accurate results.With the focus on accuracy and computational effort,we present a comparison between different methods to apply an effective pressure gradient,efficient boundary conditions,as well as two LB implementations based on pore-matrix and pore-list data structures.展开更多
文摘This paper deals with a class of nonlinear boundary value problems which appears in the study of models of flows through porous media. Existence results of asymptotic bifurcation and continua are reported both for operator equations and for boundary value problems.
文摘Theoretical equations for computing sensitivity coefficients of wellbore pressures to estimate the reservoir parameters in low-permeability reservoirs conditioning to non-Darcy flow data at low velocity were obtained. It is shown by a lot of numerical calculations that the wellbore pressures are much more sensitive to permeability very near the well than to permeability a few gridblocks away from the well. When an initial pressure gradient existent sensitivity coefficients in the region are closer to the active well than to the observation well. Sensitivity coefficients of observation well at the line between the active well and the observation well are influenced greatly by the initial pressure gradient.
文摘During the development of low permeability reservoirs. the interaction between fluid flow and rock mass deformation is obvious. On the basis of fluid mechanics in porous media and elasto plastic theory. the author presents an equivalent continuum model to simulate fluid flow in fractured low permeability oil reservoir coupled with geo stress. The model not only reflects the porosity change of matrix, but also the permeability change due to the opening and closing of fracture. By analyzing of simulation results, the changes in porosity and permeability and their effect on oil development are studied.
文摘The authors investigate the sensitivity of hydrostatic pressure of flows through porous media with respect to the position of the soil layers. Indeed, these induce discontinuities of the porosity which is a piecewise constant coefficient K of the partial differential equation satisfied by the pressure u and it leads to the computation of the derivative of u with respect to changes in position of discontinuity surface of K.The analysis relies on a mixed formulation of the problem. Preliminary numerical simulations are given to illustrate the theory. An application to a simple inverse problem is also given.
文摘Lattice-Boltzmann(LB)simulations are a common tool to numerically estimate the permeability of porous media.For valuable results,the porous structure has to be well resolved resulting in a large computational effort as well as high memory demands.In order to estimate the permeability of realistic samples,it is of importance to not only implement very efficient codes,but also to choose the most appropriate simulation setup to achieve accurate results.With the focus on accuracy and computational effort,we present a comparison between different methods to apply an effective pressure gradient,efficient boundary conditions,as well as two LB implementations based on pore-matrix and pore-list data structures.
