This diagram shows the geometric configuration, coordinate directions, and boundary conditions used for the two-zone flat plate example case.

Zone 1, on the left, is 25 by 65 by 3, and zone 2, on the right, is 49 by 65 by 3. The rightmost boundary of zone 1 is coupled to the leftmost boundary of zone 2. The origin is at the lower-left corner of zone 1, with the x direction and i index directed to the right, and the y direction and i index directed up.

The zone boundaries are labeled with the boundary condition used there, as follows.

Boundary   Boundary Condition

Zone 1, left   Inflow
Zone 1, bottom Symmetry
Zone 1, top Outflow
Zone 2, bottom Solid wall
Zone 2, top Outflow
Zone 2, right Outflow