Simulation with accurate direct-sun calculations (The Six-Phase Method)

An F-Matrix simulation with accurate treatment of direct-solar component, which can also be thought of Six-Phase simulation, is essentially a sequence of three independent simulations whose results are then combined by subtraction and addition. The Six-Phase Method is mostly similar to the Five-Phase Method except for inclusion of the F-Matrix in the workflow. A pictorial representation of the Six-Phase method is shown in Figure 77. As shown in the figure, the first simulation involved in this method is a standard F-Matrix simulation. Subsequent to that, an F-Matrix simulation with only direct-solar component is performed. Assuming that a complete FH- type F-Matrix simulation described in section 7.3 and 7.5 has already been performed, a direct FH- matrix with a single ambient bounce can be generated as:

rfluxmtx -v -ff -ab 1 -ad 10000 -lw 1e-5 -c 5000 -n 8 objects/GlazingVmtx.rad fports/FH.rad -i roomFmtxHDir.oct > matrices/fmtx/FHD.fmx

The corresponding direct Daylight matrix with zero bounces can be generated as:

rfluxmtx -v -ff -ab 0 -ad 10000 -lw 1e-5 -c 1000 -n 8 objects/GlazingVmtx.rad skyDomes/skyglow.rad -i roomFmtxHDir.oct > matrices/dmtxd/daylightF.dmx

The direct FH matrix and Daylight matrix can be merged into a single matrix as:

dctimestep -of matrices/fmtx/FHD.fmx matrices/dmtxd/daylightF.dmx > matrices/dmtx/DFHD.dfmx

The rest of the commands for the direct-solar component of the F-Matrix simulation are similar to the ones for the direct-solar component of the Three-Phase Method. The model considered for the direct-sun coefficient simulation will be completely black except for the suns and the shading systems. The octree for this simulation can be generated as:

oconv materialBlack.rad roomBlack.rad skies/suns.rad skies/suns6.rad matrices/tmtx/GlazingBSDF.rad overhang/aluminiumGrate.rad > modelWithSunsTestFH.oct

Except for the inclusion of the non-coplanar shading device (overhang/aluminiumGrate.rad), this command is identical to the one used for the direct-sun coefficients in the Five-Phase Method.

Figure 77. There are three separate simulations involved in the Six-Phase Method. The first simulation is an F-Matrix simulation of F1, FH or FN type. The second simulation that isolates the direct-solar component of the first simulation involves creating an F-matrix with a single ambient bounce. The calculation parameters for other matrices are the same as those for the direct-solar calculation in the Five-Phase Method. The final simulation involves the calculation of direct-sun coefficients with the commands that are exactly same as that followed in the direct-sun coefficient calculations for the Five-Phase Method.

Figure 78. Image-based result for a Six-Phase simulation.

Full set of commands for the Six-Phase Method is provided in section E.6 of Appendix E. Figure 78 shows the image-based results for the Six-Phase method generated for a particular hour.