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CFL3D Version 6.7

Welcome to the CFL3D Version 6 Home Page!

NOTE: THE CFL3D WEBSITE HAS MOVED TO: (The current site will soon go away.) Please make a note of it.

CFL3D is a structured-grid, cell-centered, upwind-biased, Reynolds-averaged Navier-Stokes (RANS) code. It can be run in parallel on multiple grid zones with point-matched, patched, overset, or embedded connectivities. Both multigrid and mesh sequencing are available in time-accurate or steady-state modes.

CFL3D has been used to support numerous NASA programs since the late 1980s. It continues to be used today, particularly for validation and verification activities such as those documented on the NASA Langley Turbulence Modeling Resource (TMR) website.

Two U.S. Postage Stamps, issued in 2006, commemorate X-Planes, a series of experimental vehicles involving NASA, the U.S. military, and aerospace companies. The computer-generated images shown on the stamps were produced from results using the CFL3D code (computed by the NASA Langley Geometry Laboratory).

X-Plane US postage stamp Express Mail X-Plane US postage stamp Priority Mail



These pages provide the documentation for the newest version of CFL3D, Version 6.7. CFL3D is a long-standing Navier-Stokes CFD code developed at NASA Langley Research Center for solving 2-D or 3-D flows on structured grids. The code has been in existence since the late 1980's, is very reliable and stable, and has many capabilities and options. We invite you to start off by perusing the Test Cases and Image Gallery, by clicking on the buttons to the left.

Version 6.7 (released on February 1, 2017) represents only relatively minor upgrades over Version 6.6 (released on April 14, 2011). Most of the changes reflect minor bug fixes or new capabilities, particularly with respect to several new keyword input capabilities. See New Features for details on these.

There is no formal User's manual available for Version 6, but there is a manual for Version 5 and virtually all of this documentation is also applicable to Version 6. There are many options in V6 that were not available in V5, and a few that are handled slightly differently. Usage of these new options is described in New Features. You may download a pdf file of the Version 5 User's Manual (either by chapter or in total) by clicking on the "Version 5 Manual" selection in the index to the left.

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CFL3D is available from:

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CFL3Dv6 can be run in either the standard (sequential) mode or in distributed/ parallel mode. Whereas in the sequential mode all blocks at all multigrid levels reside on one processor, in the distributed/parallel mode each processor will have one or more grid blocks residing on it. The coarser levels required for multigrid reside on the same processor as the finer parent block. The computations for a particular grid block are not currently split among multiple processors. As a result, single-block grids cannot be run in parallel. However, a Block Splitter tool is provided to facilitate conversion of an existing grid and input file to run in a parallel environment.

The parallel code utilizes the Message Passing Interface (MPI). The required MPI libraries may be "native" ones that exist on parallel processors such as the Origin 2000, the SP2 or the T3E, or, for workstation clusters, the portable MPI implementation, MPICH.

The code displays reasonably good scalability with increasing processor count for load balanced cases. Scaling tests have been conducted on SGI Origin 2000, CRAY T3E, and "Beowulf" Pentium systems.

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CFL3D does not include grid generation capability; a separate grid generator must be obtained. CFL3D can work with grids in any one of 3 formats: CGNS, PLOT3D, or CFL3D.

CFL3D also does not provide postprocessing visualization tools. For output, the code can create results in two widely-used formats: CGNS and/or PLOT3D (there is also some limited Tecplot output capability).


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Responsible NASA Official: Christopher Rumsey
Page Curator: Christopher Rumsey
Last Updated: 06/01/2022