Governing equations of radiation analysis in ladybug

[ahad]

hi all

could you please give me those equations that govern radiation analysis in ladybug? I gonna find mathematical documentation that governs radiation analysis in ladybug!

best

[ahad]

There is below methods in Duffie solar engineering book:
** clear sky…Hottel model
** cloudy sky …Erbs et all or Rabl or Liu & Jordan or …
** radiation on sloped surfaces: 1- isotropic 2. anisotrpic model
** anisotropic : 1. HDKR 2. Perez

could you please tell me, which above methods used in ladybug?
i need your answer for comparing my result with other authors.

[ahad]

@mostapha
like as you know, there is some mehods to gain radiation analysis on a surface,
coluld you please tell me ladybug use which method?

thanks in advance!
Park

[wim]

Hi - I see now that the post I linked to on the Rhino Discourse was actually in a thread that was started by you.

There is a lot of information in that thread and these new posts don’t really seem to indicate that that was absorbed. At any rate, it would probably be better to continue in the original thread and ask specific follow-up questions there.

What is your assumption to calculate radiation on inclined surfaces?

I’ll also add that all of the 3 listed methods at the top are anisotropic. Most times, people use the EPW hourly radiation values, which account for cloud cover but it is also possible to do a clear sky radiation simulation as you see here

-wim

[ahad]

dear admin
unfortunately, i didnt get it.
i try to explain my problem:

There is below methods in Duffie solar engineering book:
** clear sky…Hottel model
** cloudy sky …Erbs et all or Rabl or Liu & Jordan or …
** radiation on sloped surfaces: 1- isotropic 2. anisotrpic model
** anisotropic : 1. HDKR 2. Perez

could you please tell me, which above methods used in ladybug?
i need your answer for comparing my result with other authors.

best

[mostapha]

Ladybug uses radiance’s gendaymtx to generate the sky. See gendaymtx documentation for more information.

[mostapha]

@wim

There is a lot of information in that thread and these new posts don’t really seem to indicate that that was absorbed. At any rate, it would probably be better to continue in the original thread and ask specific follow-up questions there.

Agreed! This is another one that you might want to check:

Data reliability

Hi everyone, I’m an Italian student at the University of Pisa. Due to the fact that I’m doing my thesis through Ladybug and Honeybee I had to verify Ladybug+Honeybee data reliability. Down here you will be able to check them. The analysis has been run for Pisa during May, September and January. Reading the results I have extracted from the softwares I can say they are quite good. The data pattern is fine and the most difference can be found on the north exposition. This is because of the Itali…

The link to the original discussion:

Data reliability