双重介质中地下水污染模型沿特征线外推的向后Euler-Galerkin格式及交替方向预处理迭代解

Alternating direction preconditioned iteration for backward Euler-Galerkin methods for groundwater pollution problem in aggregated porous media

对双重介质中地下水污染模型构造了沿特征线方向外推的向后Euler-Galerkin格式,并用交替方向预处理迭代法解沿特征线外推的向后Euler-Galerkin法在每一时间步所产生的代数方程组。在没有增加计算量和破坏精度的前提下得到了最优的L2-模误差估计,并且关于时间是高精度的。

A backward Euler-Galerkin method is applied for groundwater pollution problems in aggregated porous media, and an alternating direction preconditioned iterative method with extrapolated along characteristics is used to solve the approximately discrete equations. Optimal order L^2-error estimates are obtained under optimal estimate work and with no damage to the precision. Moreover, high order accuracy with respect to time is obtained.