Changing One Relaxation Factor Moved the Converged Solution — Where Rhie–Chow Face Velocities Remember Under-Relaxation
·7 min read
In SIMPLE, cutting α_u from 0.7 to 0.3 changes the converged velocity. Standard Rhie–Chow keeps α_u on the damping term; Majumdar's face store removes it.
When Pressure Rings in a Checkerboard — SIMPLE and Rhie-Chow Coupling
·6 min read
On a 48-cell periodic line the naive stencil keeps a checkerboard of 0.80, while Rhie-Chow drives the same sawtooth down to 3.1e-16.
[CFD Q&A] When simpleFoam Pressure Residual Fails to Converge
·4 min read
In simpleFoam the pressure residual jumped from 0.412 to 0.891. Dropping the p relaxation from 0.7 to 0.3 brought it near 1e-4 by iteration 200.