Aerodynamics and Energetics Modeling

Boundary Layer Computations with the 3C3D Code

3D computation of boundary layer
turbulence on a cruciform missile

The surface heat flux of profiled bodies in non-separated flow can be found from the velocity field of an ideal fluid at the surface by solving the boundary layer equations, which is often a simpler procedure than a full Navier-Stokes computation. Other pertinent data concerning the viscosity effects are also obtained this way, especially for the laminar-turbulent transition phenomenon.

The equations deduced from the usual first-order boundary layer assumptions are solved in direct mode by the 3C3D code with no further limitations. The field of application ranges from the incompressible (including in water with thermal effects) to hypersonic, assuming chemical equilibrium. Various turbulence and transition models are available. Complex geometric configurations like wing-fuselage and wing-pylon-nacell assemblies can also be computed, although these are in the margin of the boundary layer assumptions.

The code input data is the surface geometry and the ideal fluid velocity field at its surface. The input file format is not set, and can be easily adapted to each particular situation. Various post-processing possibilities are included in 3C3D , especially for computing the equivalent transpiration velocity and the displacement thickness velocity. A data result file can be produced after each computation for direct use by the Tecplot graphic software. The user has the choice of the information contained in this file.

The source code is written in Fortran77 and can be used on a workstation.

Last Update: 9 May 2006 - © ONERA 2009 - Terms of use