The Suite

Courant Fluids

Available10 September 2026

What it runs on
OpenFOAM, on your machine
What it decides
Timestep, scheme and convergence
Cost of being wrong
A week of wall clock, and a wrong answer

What it checksMeasured

  1. 01
    Courant violation

    A timestep too long for the mesh, climbing one step at a time.

    Co 113 at rated speed
  2. 02
    Unbounded convection

    A scheme that oscillates on k, and moves the wake with it.

    limitedLinear on div(phi,k)
  3. 03
    A plateau read as converged

    Flat is not converged, and it looks exactly like converged.

    1e−3, flat for 400 steps

What comes back

  • The cause, and the line of solver output it came from
  • The change, as a diff you can reverse
  • Physics checks, measured against their limits
  • A record somebody else can open on a link

Certified against real solves

  • simpleFoam
  • pimpleFoam
  • pisoFoam
  • rhoPimpleFoam
  • interFoam
  • buoyantPimpleFoam

Exercised against real solver output in Docker, on OpenFOAM's own tutorial cases with faults injected into them.

Standing

Shipping. Sixteen of the twenty-five failure modes are certified against real solves in Docker, on OpenFOAM's own tutorial cases with faults injected into them. The remaining nine are in the taxonomy and not yet certified.