An improved algorithm to smooth graded quadrilateral meshes preserving theprescribed element size

In the generation of quadrilateral unstructured meshes, special attention i s focussed to the shape of the elements. This is because it is well known t hat the distortion of the elements and the accuracy of the analysis are clo sely related. However, in adaptive schemes it is also essential that the ne wly generated mesh meets the prescribed element sizes in order to obtain a solution with the desired precision. In 1982 Giuliani developed a robust re zoning algorithm based on geometrical criteria. It gives proven results in a smooth element size distribution, but elements do not verify the prescrib ed element size when sharp distributions appear. This paper presents a modi fication of the Giuliani method that generates nondistorted elements while preserving the element size. Similar to the original method, this modificat ion can be extended to three-dimensional cases. Copyright (C) 2001 John Wil ey & Sons, Ltd.