An Automatic Adaptive Reenement and Dereenement Method for 3d Elliptic Problems
نویسندگان
چکیده
We present the theory and implementation for a new automatic adaptive h-re nement and -dere nement method for twoand three-dimensional elliptic problems. An exact lower error bound for dere nement is obtained theoretically in terms of the nite element solution, complementing the various known upper error bounds for re nement. These error bounds are used to determine where to insert and/or remove mesh elements. To implement the method, we utilize an adaptive twoand three-dimensional Delaunay tessellation that preserves the Delaunay properties while locally adding points to, or deleting points from, the previous Delaunay mesh. We provide computational examples for twoand three-dimensional elliptic problems on unstructured grids.
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