渗流驱动问题的多步特征有限元方法

Multistep Characteristic Finite Difference Method for Miscible Displacement of Incompressible Flow in Porous Media

不可压缩可混溶驱动问题的数学模型是由椭圆型压力方程和抛物型饱和度方程偶合而成的非线性偏微分方程组.用有限元法离散压力方程,向后多步特征有限元法离散饱和度方程,提高了时间误差阶,并得到与单步特征有限元法相同的L2(Ω)模先验误差估计.

Miscible displacement of incompressible fluid in porous media is modeled by a nonlinear coupled system of partial differential equations. A procedure is defined to discrete the pressure equation by a standard finite element method and the concentration equation by a muhistep characteristic finite element method. Approximation order is enhanced,and the same order a prior error estimate in L2（ Ω ）-norm is derived as the single step characteristic method.