Mixed Finite Element Methods
نویسندگان
چکیده
A new mixed nite element method on totally distorted rectangular meshes is introduced with optimal error estimates for both pressure and velocity. This new mixed discretization ts the geometric shapes of the discontinuity of the rough coeecients and domain boundaries well. This new mixed method also enables us to derive the optimal error estimates and existence and uniqueness of Thomas's mixed nite elements method on distorted rectangular grids 19]. The lowest order Raviart-Thomas mixed nite rectangular element method becomes a special case of both methods, when all the elements are degenerated to parallelograms.
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