PEGASUS 5 is a code which performs a pre-processing step for the Overset CFD method. The code prepares the overset volume grids for the flow solver by computing the domain connectivity database, and blanking out grid points which are contained inside a solid body.

PEGASUS 5 is the latest version of the PEGASUS series of mesh interpolation codes. It is a fully three-dimensional code. The main purpose for the development of this latest version was to significantly decrease the number of user inputs required and to allow for easier operation of the code. A basic description of methods used in PEGASUS 5 is described in this manual, and a complete list of all user inputs is also provided.
 

The major new features are as follows:

• The minimum holes can be automatically cut if the boundary conditions for each mesh are supplied.
  
  
• Growth of the minimum holes is achieved through "level 2" interpolation. In level 2 interpolation, interpolated boundary points receive information from the finest mesh available in overlapping regions. As a result, link lists (required in Version 4) are no longer used.
  
  
• Outer boundaries are automatically specified if the boundary conditions for each mesh are supplied.
  
  
• Memory is dynamically allocated at run time. The code is written almost entirely in Fortran 90, and memory allocation is achieved through Fortran 90 constructs. Some subroutines are written in Fortran 77, which has been designated as a standard subset of Fortran 90. There is no C code used in PEGASUS 5.
  
  
• Restarting is similar to the UNIX "make" facility. As new meshes or inputs are added, PEGASUS will recognize these new changes and performs only the required operations.
  
  
• Existing hole definitions contained in IBLANK records of PLOT3D grid files can be used to define the holes in PEGASUS 5. This allows stand-alone hole-cutting methods to be employed if desired. In addition, legacy grid systems can be used with existing hole definitions.