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How can i calculate Usefull Daylight Illuminance UDI with my own parameters or visualize data from ill files from OpenStudio and Radiance?

asked 2018-03-08 14:26:16 -0500

altamar gravatar image

updated 2018-03-08 17:57:17 -0500

The Usefull Daylight Illuminance is a parameter that describes the percentage of time a point has been between a determined range of illumination. The UDI has three variantes, the percentage of time a point has been below a minimum illuminance level (UDI_under), the percentage of time a point has been between a desired level (UDI_useful) and the percentage of time a point has been above a maximum level (UDI_over).

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@altamar thanks for the announcement, however this isn't a question. Feel free to reformat it as a question and then answer it.

MatthewSteen gravatar imageMatthewSteen ( 2018-03-08 15:25:29 -0500 )edit

Noice! Seconding Matt's advice, and also I'd add that you should clarify the format of the illuminance file you speak of. Is this for OpenStudio/RadianceMeasure ill files, or Honeybee, or...???

rpg777 gravatar imagerpg777 ( 2018-03-08 16:29:02 -0500 )edit

edited and uploaded some images!

altamar gravatar imagealtamar ( 2018-03-08 17:41:38 -0500 )edit

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answered 2018-03-08 17:55:59 -0500

altamar gravatar image

I wrote a class in python (ready to use in Jupyter notebook) to calculate and plot the UDI from a ILL file from Radiance and OpenStudio . This class also visualize an illuminance map at specific day and time and also plot the illuminance profile along x or y.

The class reads the ILL file from Radiance and does everything described above.

Feel free to try it and suggestions are welcomed, it is on github


Illuminance map

Illuminance along x/y

I have been a reader since 5 o 6 years, and i feel very excited and glad to contribute to this community.

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Asked: 2018-03-08 14:26:16 -0500

Seen: 38 times

Last updated: Mar 08