摘要

A two-grid finite volume element method, combined with the modified method of characteristics, is presented and analyzed for semilinear time-dependent advection-dominated diffusion equations in two space dimensions. h) is reduced to the solution of two small (one linear and one nonlinear) systems on the coarse-grid space (with grid size H) and a linear system on the fine-grid space. An optimal error estimate in H-1 -norm is obtained for the two-grid method. It shows that the two-grid method achieves asymptotically optimal approximation, as long as the mesh sizes satisfy h = O(H-2). Numerical example is presented to validate the usefulness and efficiency of the method.

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