The Wall node includes a set of boundary conditions describing fluid-flow conditions at stationary, moving, and leaking walls.

Select a Boundary condition for the wall.

No slip is the default boundary condition for a stationary solid wall for laminar flow (and SST, Low Re k-ε, Algebraic yPlus, L-VEL, and Spalart–Allmaras turbulence models). The condition prescribes u = 0; that is, the fluid at the wall is not moving.

The Slip option prescribes a no-penetration condition, u·n = 0. It is implicitly assumed that there are no viscous effects at the slip wall and hence, no boundary layer develops. From a modeling point of view, this can be a reasonable approximation if the main effect of the wall is to prevent fluid from leaving the domain.

This boundary condition may be used to simulate a wall where fluid is leaking into or leaving the domain with the velocity u = ul through a perforated wall. The components of the Fluid velocity ul on the leaking wall should be specified.

This section is displayed by clicking the Show button () and selecting Advanced Physics Options.