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Setting up your case for ShockLens

ShockLens reads three things. The shock needs the density field. Separation and the wall-pressure rise need the wall patch. The breathing spectrum needs a time series of wall pressure. Here is exactly what to add to your OpenFOAM case so all three exist, and how to point case.yml at them.

If a piece is missing, ShockLens still runs and just warns, so you can start with the field only and add the rest later.

What produces each input

ShockLens wants You add case.yml key
density field (shock, contours, schlieren) nothing, foamToVTK writes rho/U/p vtk
skin friction + wall pressure (separation, pressure rise) wallShearStress function object wall_vtk, cf_denom
unsteady wall pressure (RMS, breathing rate) probes function object probe_file, probe_col

1. The field (always)

Run foamToVTK after the solver. It writes the internal field to VTK/<case>_<t>.vtk and every boundary patch to VTK/<patch>/<patch>_<t>.vtk. Density comes for free. Point vtk: at the internal-field file.

2. Wall shear and wall pressure (for separation)

Add this to system/controlDict so the wall patch carries wallShearStress (and p rides along automatically):

functions
{
    wallShearStress
    {
        type            wallShearStress;
        libs            ("libfieldFunctionObjects.so");
        patches         (bottom);          // your wall patch name
        writeControl    writeTime;
    }
}

After foamToVTK, the wall patch file VTK/bottom/bottom_<t>.vtk has both wallShearStress and p. Point wall_vtk: at it.

cf_denom is the dynamic pressure that turns wall shear into skin friction: cf_denom = 0.5 * rho_inf * U_inf^2. For the bundled ramp (rho_inf = 1.4, U_inf = 2) that is 2.8. ShockLens projects the shear onto the local wall tangent, so an inclined or curved ramp is handled correctly, not just a flat plate.

3. Time-resolved wall pressure (for the breathing spectrum)

Add a probes function object with a few points just above the wall:

    wallPressureProbes
    {
        type            probes;
        libs            ("libsampling.so");
        writeControl    timeStep;
        writeInterval   1;
        fields          (p);
        probeLocations
        (
            (0.05 1e-4 0)
            (0.10 1e-4 0)
            (0.15 1e-4 0)
        );
    }

This writes postProcessing/wallPressureProbes/0/p, one column of time then one per probe. Point probe_file: at it and set probe_col to the probe under the interaction (1 is the first probe after the time column). Set writeInterval small enough to resolve the unsteadiness if you want a clean spectrum.

The case.yml that ties it together

name: myCase
vtk: case/VTK/case_8.vtk
fields: [rho]
detector: oblique_ransac
nx: 320
ny: 180
mach: 2.0
theta_deg: 15.0
wall_vtk: case/VTK/bottom/bottom_8.vtk
cf_denom: 2.8
probe_file: case/postProcessing/wallPressureProbes/0/p
probe_col: 3

Then one command does everything:

shocklens run-case myCase.yml --outdir results

You get the results summary printed and the figures written to results/. The YAML is the only per-case file, so this works for any case, not just the ramp.

Later: heat flux for transition

When you move to transition work, add a wallHeatFlux function object the same way. ShockLens does not use it yet, but it is the natural next wall quantity, so writing it now means the data is there when the regime classifier lands.