Remarks and hints

To ensure that a structure is mapped properly onto one or more cell faces the defining poly-line should intersect the line segments connecting the cell cen­tres. If the latter is not the case a warning is issued in the simulation-log and the structure is mapped onto the nearest cell face with a similar alignment as the defining line segment. To ensure a proper mapping simply extent the poly-line defining the structure location so that it intersects a line segment connecting cell mid-points, see Figure 6.32

Figure 6.32        Definition of cell mid-points

The affected cell faces are written to the simulation log for inspection. The for­mat being:

n is an index of the number of cells affected, j and k refers to the individual cells. The value of Top is either 0 or 1 depending on whether the cell face is to the right or at the top of the cell. Finally the Posi value indicates whether the cell is the upstream (1) or the downstream side of the structure. Please note that the upstream and downstream definition is only of importance if the loss factors are asymmetric across the structure or the invert levels are differ­ent upstream and downstream.