KB12: Wall Temperatures KB12: Wall Temperatures
Storage of wall temperatures
As each grid cell can include up to 6 walls, the storage of the wall temperatures has to be different from the other variables, where only one value per grid is stored.
To store all walls in the Main File Atmosphere, 3 different temperature variables are used:
X- Wall is the wall parallel to the x-axis and to the front
Y- Wall is the wall parallel to y-axis and to the left
Z-Wall is the wall parallel to the z-axis and on the bottom.
The wall temperature values are always stored in the grid cell, to which the wall forms the left, front or bottom boundary.
The following sketch illustrates the allocation of X- and Y-walls in case of a simple building:
This building covers 4 grid cells: (2,1) - (3,1) - (2,2) - (3,2).
The left corner of the building in (2,1) contains both the left X-Wall as well as the front Y-Wall of the corner. In contrast, cell (3,2) contains no walls although it is a part of the building. Following the rule given above, the walls to the right and to the rear in this grid cell are assigned to the cell (4,2) (right wall) and (3,3) (rear wall).
For the Z-Wall, the same principle applies.