Functions
	channel_sdf (nx, ny, nz, ylo, yhi)

	run (N, Solver, rho=1.0, mu=0.1, dt=50.0, F=0.01, max_steps=400)

	main ()

Detailed Description

Verification (flow): plane Poiseuille flow through an SDF-defined channel, driven by a body force, with
Robust-Scaled cut-cell IBM no-slip at the (non-grid-aligned) walls. The steady profile is the parabola
u(y) = F/(2 mu) (y - ylo)(yhi - y); because it is exactly quadratic and a second-order scheme is exact on
quadratics, the cut-cell solution must match it AT EVERY GRID NODE to solver tolerance -- at every
resolution and on both the staggered and collocated meshes.

We therefore verify POINTWISE: max_node |u - u_analytic|. (The old version of this script compared the
discrete u.max() to the continuum peak U_max = F H^2/(8 mu); with half-integer walls the channel centre
sits 0.5h from the nearest node, so u.max() is a fixed amount below U_max and dividing by U_max fabricated
a "converging" error -- a sampling artifact, not discretization error. The pointwise metric below actually
tests method order and would catch a genuine first-order regression.)

Uses the canonical `peclet.flow` module (one GPU as plain `python`, or multi-rank under `mpirun -np N`).
Physical units: set_rho/set_mu, body force F is a force per unit volume (= -dp/dx). Grid spacing = 1.

Function Documentation

◆ channel_sdf()

verify_poiseuille_flow.channel_sdf	(	nx,
		ny,
		nz,
		ylo,
		yhi
	)

Global SDF as a 3-D array sdf[x,y,z]; negative inside the solid walls.

Definition at line 26 of file verify_poiseuille_flow.py.

Referenced by run().

◆ run()

verify_poiseuille_flow.run	(	N,
		Solver,
		rho = `1.0`,
		mu = `0.1`,
		dt = `50.0`,
		F = `0.01`,
		max_steps = `400`
	)

Solve one channel case at wall-to-wall resolution N; return the pointwise node error vs the parabola.

Definition at line 34 of file verify_poiseuille_flow.py.

References channel_sdf().

Referenced by main().

◆ main()

verify_poiseuille_flow.main ( )

Run staggered + collocated at a few N, print the pointwise node error, exit non-zero on failure.

Definition at line 75 of file verify_poiseuille_flow.py.