A local mesh-refinement technique for incompressible flows

As part of a Multi-Grid scheme for the solution of the Navier-Stokes equations in primitive variables, we introduce a local mesh refinement procedure. New cartesian sub-grids are introduced into regions where the estimated truncation errors are too large. Through the Multi-Grid processing, informations is transferred among the grids in a stable and efficient manner. A simple pointer system allows the storage of the dependent variables, without increasing in the required computer memory. Two computed examples of incompressible flow problems are discussed.