• Converge Criterion—When the correction for the solved variables drops below the specified value, the code stops (Steady) or moves to the next time-step (Transient).

• Environment Temperature—This is important if there is any open boundary exterior to the domain. The temperature exterior to the solution domain is taken as ambient temperature of 300 K.

• Number of Rays—Determines the view factors between boundaries, interfaces, and sources. The greater the number of rays, then greater the precision of the view factor calculations and associated radiative heat transfer. The default number of rays is 256, which is equivalent to dividing the surface of the sphere surrounding a radiating point or surface into 28 solid angles. The greater the number of rays, the greater the computational expense for the analysis.

• Grain Size—Size of the cell face groups used to determine view factors. Default grain size is 1, which corresponds to view factors calculated for every opaque cell face.

• Source—Add or remove a radiation source.