Mesh refinement without Delaunay criterion violation

Hi,

I have been doing a fair bit of mesh refinement lately and I am wondering if I am doing it right. I normally refine triangular mesh using the refine button. But this always lead to some cells violating Delaunay criterion. I normally flip edges to correct this but when the refinement zone is big this can be very time consuming. Is there another way to do this? Can a condition (ie not to violate delaunay criterion) be used prior to refinement?

Thanks,
Louis.

Louis,
refinement is (currently) always done by simply splitting triangles by adding vertices at the center points of the edges. Thus the quality will depend directly on the quality of the source triangles, and at the borders of the refined zone mesh quality will deteriorate. Indeed currently the only ways of improving are flipping edges/moving nodes or the smoothing algorithms.
Peter