explicit radiation balance

[Peterbilt]

I just did a series of WUFI PRO (1-D) runs for a cathedral roof for Madison Wisconsin USA).

The only way I could get the runs to not have more than 1k convergence failures was to unselect "explicit radiation balance" under Surface Transfer Coefficients, even though when I clicked on "run" a dialog "Explicit radiation balance disabled but inclination is 20 degrees" (the cathedral roof is a 4:12 pitch, around 20 degree roof slope).

I could not find any info in the WUFI help or in the Forum on just what explicit radiation balance is or how it works and what sort of impact its selection/unselection means in terms of run results.

Ideas?

Thanks - Peter

[Christian Bludau]

Hi Peter,
try to switch on the "adaptive time step control". More important then the convergence failures are usually the balances, they should be close to each other. You find them in the table appearing after the calculation.
Christian