I am modeling solar radiation gain into an enclosed system with and without a sunshield. After setting up the problem, initialising, adding in solar and gray body radiation, setting emissivity, reflectance and transmissiviry values, generating patches I get an error when trying to calculate view factors:

"Assertion error: Attempt to access unallocated BoundaryTransmissivity storage in boundary faces in 'boundary X'"

I think the problem is in my set-up, but not sure where.

Any advice would be appreciated.

The emissivity, trans and reflectance add up to 1 for all boundaries/imterfaces.

Send the quesiton to Support, either something is wrong with the setup, or more likely there is a problem here.

i advise u that u'd better have a look at the tutorial of ccm+ in which there is a detailed radiation model and it is almost the same as your work. The tutorial is very simple, and the setting of parameter is very detailed.