Hi,

I've come across this code called OVERFLOW. It seems that places like NASA are using it. Would anyone be familiar with it?

Thanks in advance

It's a 3D structured grid Navier-Stokes solver for overset meshes (Chimera grids). Originally developed at NASA Ames and used primarily for external aerodynamics applications.

hi, is it different than fluent wit more or less feature and what do u mean by overset meshes.

Fluent implements a remeshing scheme for moving body problems where by the mesh is first streched with a spring analogy and then regions are subsequently remeshed based on criteria such as allowable cell aspect ratio.

Overset / Chimera Meshes are very different. CFD-Fastran as well as Overflow both emply this method for moving body problem. Basically there are two meshes. Both the meshes are staic in that the mesh is never deformed, however one of the meshes can move around rigidly. This mesh contains cells in the immediate surrounding of the body in motion and follows the body around as it moves. The other grid is larger and covers the complete domain. The wall boundaries in the smaller grid are used as a stencil to blank out cells in the larger grid. The result is a solution on both the grids. The smaller grid containts detailed flow such as BL effects. The larger grid is less precise in the region of the moving body but the global effects of the bodies in motion can be accounted for on this grid.