{"id":357846,"date":"2024-03-19T10:23:06","date_gmt":"2024-03-19T10:23:06","guid":{"rendered":"\/forum\/forums\/topic\/how-can-i-give-different-transmissivity-with-more-than-3-wavelength-region\/"},"modified":"2024-03-19T10:23:06","modified_gmt":"2024-03-19T10:23:06","slug":"how-can-i-give-different-transmissivity-with-more-than-3-wavelength-region","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/how-can-i-give-different-transmissivity-with-more-than-3-wavelength-region\/","title":{"rendered":"How can I give different transmissivity with more than 3 wavelength region?"},"content":{"rendered":"

I used Discrete Ordinates (DO) Model since it is the only model with ‘semi-transparent’ and ‘non-gray’ mode.<\/p>\n

I want to give material A (semi-transparent) transmissivity or emissivity like this:<\/span> <\/span><\/p>\n

Thickness of the material is 0.005 m, <\/span><\/p>\n

Absorption coefficients <\/span><\/p>\n

Band 1 = 57.5<\/span><\/p>\n

Band 2 = 57.5 <\/span><\/p>\n

Band 3 = 57.5 <\/span><\/p>\n

Band 4 = 1842<\/span><\/p>\n

As I understood I cannot set internal emissivities (e) and transmissivities (t)directly to semitransparent material, may be diffuse fraction need to be set ? <\/span><\/p>\n


 <\/span>t=0.75 in 0 to 4 µm, or e = 0.25, Rho = 0<\/p>\n

t= 0.75 in 4 ~8 µm, or e = 0.25, Rho = 0<\/p>\n

t=0.75 in 8~14 µm, or e = 0.25, Rho = 0. <\/span><\/p>\n

t = 0.0001 in 14 – 1000 µm, or e = 0.9999, Rho =0<\/span><\/p>\n


But when I change BC type of  a material A from opaque to semi-transparent in boundary condition – radiation tab,
I made four bands, 0 – 4, 4 – 8, 8-14, 14-1000 µm in Model – Radiation – Number of Bands = 4<\/span><\/p>\n

but I could only change Direct \/ Diffuse Irradiation and Diffuse Fraction of each band, not transmissivity or emissivity of each band.<\/p>\n

Please, someone can guide me, it would be a great help,<\/span><\/p>\n

Is it possible to give each band different emissivit<\/span>ies or diffuse fraction? <\/span><\/p>\n

Or my assumption would be : diffuse fraction should be 1 , since reflection is zero ? <\/span><\/p>\n

 <\/span><\/p>\n","protected":false},"template":"","class_list":["post-357846","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t