Multi scale meshing for a traditional structured grid generator is a daunting task. The approach causes the fineness of the refined grids near the smaller geometric features to propagate into the field, thereby unnecessarily increasing the cell count, without bringing any practical computational benefit. In fact, it increases the computational time and also unnecessarily demands larger computational resources.
GridPro, has automated the meshing for multiscale problems with its innovative technique called nesting.
Nesting allows a user to efficiently distribute the grid points where the physics has to be captured, to read more click here.
Related articles on Structured Multiblock Meshing could be found at http://blog.gridpro.com/.