Simulation study on reduced-order model and optimal control of water flooding reservoir
XU Ming-hai
SUN Xian-hang
GONG Liang
JIA Xin-xin
WANG Zheng
LI Hui-ming
Abstract：Optimal control of water flooding reservoir production is a large-scale optimization problem accompanied with a great number of control variables and grid blocks, the relationship between control variables and objective function is governed by a set of nonlinear partial differential equations, it is a great challenge to directly numerically calculate the optimal control solutions with the current speed and storage space of computer. In this paper a reduced-order model based optimal control of water flooding reservoir is proposed using proper orthogonal decomposition (POD), the relationship between the control variables and objective function is transformed into analytic function, thus, only a small amount of POD coefficients are considered as optimization variables and are determined only using a nonlinear programming method, which considerably reduces the difficulty and the amount of calculation. The new methodology is approved on a well group of two dimensional five point well pattern. The results show that the net-present-value (NPV) obtained by the new methodology is approached to within 97.5%of the NPV obtained by the adjoint-gradient based method, besides, it is quite fast, where the achieved increase in calculation speed is more than 30 times when the number of grid is 40×40, and the larger number of grid is, the more obvious the computational speed advantage is, the calculation speed can be increased by more than 60 times when the grid number is 70×70.
Keywords：water flooding reservoiroptimal controlproper orthogonal decompositionreduced-order modelnonlin-ear programming
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 499-507 )