Chamflow 2000 will also generate better meshes by using an unstructured grid. In a structured grid, individual cells must be shaped as six-sided brick elements. Though these elements can be compressed, the shape restriction limits the user's ability to refine the grid. An unstructured grid makes it easier to generate a more efficient model by also allowing tetrahedral shapes to be used.

Running Rampant

An unstructured adaptive mesh will be featured in the new Rampant CFD package, which will be shipped to beta test sites by Creare.x Inc. this month and is expected to be ready for market by the fall. It was developed at Creare.x over a two-year period with funding from the NASA Lewis Research Center (Cleveland, Ohio). In iteratively solving a problem, the program refines the mesh by creating additional grid points in areas with intensive flow and erasing unnecessary mesh components in areas where nothing is happening.

The initial release of Rampant will model compressible flows such as those in gas turbine engines and other advanced turbomachinery that operate in the transonic and supersonic flow region. Future versions, possibly ready as soon as year's end, will incorporate solvers to handle incompressible flows. Creare.x said that it will continue to market and improve its flagship CFD code Fluent--indeed several Fluent improvements are planned for 1991.