CFD Utilities Files

REVOLVE_GRID is a revision of Todd White's original "hotdog" utility for
turning a 2-D grid and optional flow solution into a 3-space equivalent.
For axisymmetric vehicles, even at angle of attack, an initial 2-space grid
and flow solution can provide an effective start for 3-space cases once the
resulting singular grid lines are removed (see RADIAL_INTERP in conjunction
with CAPSULE_GRID procedures).

The right (starboard) half of the body of revolution is produced with a
180-degree rotation.

Input  Coordinate System:    X streamwise, Y up
Output Coordinate System:    X streamwise, Y positive to the right, Z up

The input dataset[s] are rotated about OX by the indicated angle (normally
180 or perhaps 360 degrees) to produce the specified number of grid points
uniformly spaced in the azimuthal direction.

The input 2-space grid may or may not include Z = 0.  Reading is attempted
first as multiblock 3-D (X/Y/Z), then retried as 2-D if necessary.
All file names and other control inputs are prompted for, along with the
number of species densities, ns, from which any velocity component indices
are deduced.

Any input flow field file should normally contain state variables in the
following order, with zero or more extra variables appended:

species densities (ns of them), vx & vy (no vz), temperature[s], any extras

However, this does not suit flow inputs to a radiation solver such as
NEQAIR, which expects 4 temperatures followed by species number densities.
Therefore, provision is made for NO velocity components, meaning all of the
flow variables are simply replicated at each azimumthal station.

The resulting output file MAY have one extra flow variable (3rd velocity
component) with the y and z components adjusted appropriately at each
angular station for axial symmetry.

11/09/2011  David Saunders  Initial adaptation of Todd White's hotdog tool.
05/10/2012    "      "      Testing of the function file option had been
                            overlooked, and there were indexing errors.
                            Apologies to Jay Hyatt.
04/08/2014    "      "      Todd found that flow datasets for radiation
                            calculations don't contain velocity components,
                            so there's now an option to handle that.
04/09/204     "      "      Allow for Z = 0. or not (3-D or 2-D) in the
                            input grid (automatically detected).

Authors: Todd White/David Saunders, ERC, Inc./NASA Ames Research Center, CA