Illuminance data source

Forum for users to discuss the DesignBuilder Radiance daylighting tools and ask questions

Moderator: DesignBuilder Support

kpx
Posts: 5

Illuminance data source

Postby kpx » Fri Jan 26, 2018 5:21 pm

Hi all,
Referring to v4.7, from which source are taken illuminance data when you are performing a daylight calculation,? I mean, the calculation gives as output lux values on the working plain height selected, but which are the starting values of illuminance? (This excludes option "6- CIE overcast sky (specify illuminance)" in wich you can put illuminance value at zenith point).
I've a feeling that the initial illuminance data are built only from latitude and longitude of the location, that is, they do not take into account any irradiance or illuminance data contained in the EPW file.
Can someone confirm what i'm guessing? (in the help i've not found reference about this issue)
Thank you
Alessandro
drumman
Posts: 32

Re: Illuminance data source

Postby drumman » Tue Feb 06, 2018 12:53 pm

Hi Alessandro!

You are right, the Daylight simulations in v4.7 are not capable to represent any geographic location.
It uses very generic CIE Sky models:
http://sustainabilityworkshop.autodesk.com/sites/default/files/styles/large/public/core-page-inserted-images/cloudy_daylighting.jpg

sDA and some other metricts are able to show the location specific daylight results. These type of simulations are opened only in v5 and above.

BR, Peter

Return to “Radiance Daylighting”

Who is online

Users browsing this forum: No registered users and 3 guests