Louvered skylights simulation

Hi,

I'm a Master student in Mechanical Engineering, and I'm working in California at UC Davis CLTC to complete my Master Thesis on lighting energy efficiency and daylighting.
I'm interested in daylighting simulation, and I found the following pages online giving some insights about the topic:

http://www.radiance-online.org/pipermail/radiance-general/2007-November/004577.html

I was particularly interested by the latter article, since it refers to something quite similar to what I would like to do: I want to simulate the behavior of controlled louvered skylights to get the luminance maps of the a space, possibly reproducing their motion (or, otherwise, manually setting the behavior at different angles).
I've no experience with lighting simulations environments.. could you give me a couple of suggestions? My questions are:

- Is Radiance the best simulation tool available for the object I want to simulate?

- How would you conceptually implement a louvered skylights with motion?

Thanks for your attention,
and Best Regards

···

--

Stefano Moret
California Lighting Technology Center<http://cltc.ucdavis.edu/>
University of California, Davis
633 Pena Drive
Davis, CA 95618

510-520-7923
[email protected]<mailto:[email protected]>

Dear Stefano,

I had similar projects in the past in our daylighting class where students modeled the annual performance of a tracking heliostat by modeling a discrete number of mirror settings in Daysim/Radiance and then assembled an annual *ill file using a script. In your case I probably would use DIVA-for-Rhino in combination with some Python scripting.

Best,

Christoph

···

From: Stefano Moret [mailto:[email protected]]
Sent: Tuesday, February 28, 2012 7:12 PM
To: [email protected]
Subject: [Radiance-general] Louvered skylights simulation

Hi,

I'm a Master student in Mechanical Engineering, and I'm working in California at UC Davis CLTC to complete my Master Thesis on lighting energy efficiency and daylighting.
I'm interested in daylighting simulation, and I found the following pages online giving some insights about the topic:

http://www.radiance-online.org/pipermail/radiance-general/2007-November/004577.html

I was particularly interested by the latter article, since it refers to something quite similar to what I would like to do: I want to simulate the behavior of controlled louvered skylights to get the luminance maps of the a space, possibly reproducing their motion (or, otherwise, manually setting the behavior at different angles).
I've no experience with lighting simulations environments.. could you give me a couple of suggestions? My questions are:

- Is Radiance the best simulation tool available for the object I want to simulate?

- How would you conceptually implement a louvered skylights with motion?

Thanks for your attention,
and Best Regards

--

Stefano Moret
California Lighting Technology Center<http://cltc.ucdavis.edu/>
University of California, Davis
633 Pena Drive
Davis, CA 95618

510-520-7923
[email protected]<mailto:[email protected]>

Dear Christoph,

Thanks for replying so quickly.
Two questions about what you wrote and before I delve into studying all the necessary programming:

- Is DIVA-for-Rhino better than Daysim for this? On the website I read that Daysim is capable to interface with other software in order to perform, for example, thermal simulations. Is this right?

- Is there any radiance/python script already available to study/learn from?

Thanks, regards
Stefano

···

From: Christoph Reinhart [mailto:[email protected]]
Sent: Tuesday, February 28, 2012 4:57 PM
To: Radiance general discussion
Subject: Re: [Radiance-general] Louvered skylights simulation

Dear Stefano,

I had similar projects in the past in our daylighting class where students modeled the annual performance of a tracking heliostat by modeling a discrete number of mirror settings in Daysim/Radiance and then assembled an annual *ill file using a script. In your case I probably would use DIVA-for-Rhino in combination with some Python scripting.

Best,

Christoph

From: Stefano Moret [mailto:[email protected]]<mailto:[mailto:[email protected]]>
Sent: Tuesday, February 28, 2012 7:12 PM
To: [email protected]<mailto:[email protected]>
Subject: [Radiance-general] Louvered skylights simulation

Hi,

I'm a Master student in Mechanical Engineering, and I'm working in California at UC Davis CLTC to complete my Master Thesis on lighting energy efficiency and daylighting.
I'm interested in daylighting simulation, and I found the following pages online giving some insights about the topic:

http://www.radiance-online.org/pipermail/radiance-general/2007-November/004577.html

I was particularly interested by the latter article, since it refers to something quite similar to what I would like to do: I want to simulate the behavior of controlled louvered skylights to get the luminance maps of the a space, possibly reproducing their motion (or, otherwise, manually setting the behavior at different angles).
I've no experience with lighting simulations environments.. could you give me a couple of suggestions? My questions are:

- Is Radiance the best simulation tool available for the object I want to simulate?

- How would you conceptually implement a louvered skylights with motion?

Thanks for your attention,
and Best Regards

--

Stefano Moret
California Lighting Technology Center<http://cltc.ucdavis.edu/>
University of California, Davis
633 Pena Drive
Davis, CA 95618

510-520-7923
[email protected]<mailto:[email protected]>

- Is DIVA-for-Rhino better than Daysim for this? On the website I read that Daysim is capable to interface with other software in order to perform, for example, thermal simulations. Is this right?
Diva-for-Rhino is a plug-in for Rhino that runs Radiance/Daysim and E+ in the background.

- Is there any radiance/python script already available to study/learn from?

Maybe some of the others have something?

···

From: Stefano Moret [mailto:[email protected]]
Sent: Tuesday, February 28, 2012 8:06 PM
To: Radiance general discussion
Subject: Re: [Radiance-general] Louvered skylights simulation

Dear Christoph,

Thanks for replying so quickly.
Two questions about what you wrote and before I delve into studying all the necessary programming:

Thanks, regards
Stefano

From: Christoph Reinhart [mailto:[email protected]]<mailto:[mailto:[email protected]]>
Sent: Tuesday, February 28, 2012 4:57 PM
To: Radiance general discussion
Subject: Re: [Radiance-general] Louvered skylights simulation

Dear Stefano,

I had similar projects in the past in our daylighting class where students modeled the annual performance of a tracking heliostat by modeling a discrete number of mirror settings in Daysim/Radiance and then assembled an annual *ill file using a script. In your case I probably would use DIVA-for-Rhino in combination with some Python scripting.

Best,

Christoph

From: Stefano Moret [mailto:[email protected]]<mailto:[mailto:[email protected]]>
Sent: Tuesday, February 28, 2012 7:12 PM
To: [email protected]<mailto:[email protected]>
Subject: [Radiance-general] Louvered skylights simulation

Hi,

I'm a Master student in Mechanical Engineering, and I'm working in California at UC Davis CLTC to complete my Master Thesis on lighting energy efficiency and daylighting.
I'm interested in daylighting simulation, and I found the following pages online giving some insights about the topic:

http://www.radiance-online.org/pipermail/radiance-general/2007-November/004577.html

I was particularly interested by the latter article, since it refers to something quite similar to what I would like to do: I want to simulate the behavior of controlled louvered skylights to get the luminance maps of the a space, possibly reproducing their motion (or, otherwise, manually setting the behavior at different angles).
I've no experience with lighting simulations environments.. could you give me a couple of suggestions? My questions are:

- Is Radiance the best simulation tool available for the object I want to simulate?

- How would you conceptually implement a louvered skylights with motion?

Thanks for your attention,
and Best Regards

--

Stefano Moret
California Lighting Technology Center<http://cltc.ucdavis.edu/>
University of California, Davis
633 Pena Drive
Davis, CA 95618

510-520-7923
[email protected]<mailto:[email protected]>

Hi!

-Is Radiance the best simulation tool available for the object I want to simulate?

-How would you conceptually implement a louvered skylights with motion?

Hard to answer the first question. For the second, I used environment variable in my scene files for similar applications. That allows you to use any tool you could imagine (I used perl scripts in most cases) to calculate the transformation (if you want to use xform) and other parameters, assign these to environment variables and have these expanded in the scene file. You may build your own tools on the output of other Radiance programs, e.g. I used gensky to get the sun vector when I scripted a tracking mirror and only had to filter out the relevant information using regular expressions.

One step further would be to write a tool that writes not only these parameters, but the geometry description to stdout, so that it could be embedded in the scene file. Radiance is very flexible when it comes to integration with other, external tools.

Cheers, Lars.

Hi Lars,

So in this case you used tools within Radiance or graphical interfaces which are running Radiance on the back?
I've seen that Rhyno isn't free, so I would like to try with Daysim and some Python scripts to try to simulate my system. According to old posts in the mailing list this should work, am I right? Any suggestion avbout it?

Thanks, Stefano

···

-----Original Message-----
From: Lars O. Grobe [mailto:[email protected]]
Sent: Wednesday, February 29, 2012 12:40 AM
To: Radiance general discussion
Subject: Re: [Radiance-general] Louvered skylights simulation

Hi!

-Is Radiance the best simulation tool available for the object I want
to simulate?

-How would you conceptually implement a louvered skylights with motion?

Hard to answer the first question. For the second, I used environment variable in my scene files for similar applications. That allows you to use any tool you could imagine (I used perl scripts in most cases) to calculate the transformation (if you want to use xform) and other parameters, assign these to environment variables and have these expanded in the scene file. You may build your own tools on the output of other Radiance programs, e.g. I used gensky to get the sun vector when I scripted a tracking mirror and only had to filter out the relevant information using regular expressions.

One step further would be to write a tool that writes not only these parameters, but the geometry description to stdout, so that it could be embedded in the scene file. Radiance is very flexible when it comes to integration with other, external tools.

Cheers, Lars.

_______________________________________________
Radiance-general mailing list
[email protected]
http://www.radiance-online.org/mailman/listinfo/radiance-general

Hi Stefano,

I did not use a graphical user interface, but embedded my scripts'
output into the scene files.

I guess you are aware that Radiance will expand any line starting with
"!command" by the output of the programm "command".

So e.g. having a line "!genSkylight.pl $SIMTIME" you would have
"genSkylight.pl" called when you pass the scene into oconv. Assuming
$SIMTIME is set to the date and time that you want to simulate, your
script could generate the geometry for the skylight and write it to
stdout. If you also have a line "!gensky $SIMTIME" (plus the other
gensky options) somewhere in your scene, you would make sure that the
sky model matches the skylight's configuration. In the end, you would
simply export the environment variable $SIMTIME and call rad scene.rif
to run the simulation. This could e.g. happen in a loop to go through a
full day.

Of course there is a bunch of specialized programs out there, some with
a nice GUI, using Radiance as a back-end. I still wanted to draw your
attention to the fact that it is very easy to add this kind of "dynamic
objects" to your scene using command expansion.

I do not know about Daysim+Python, maybe others on the list can comment.

Cheers, Lars.

···

Hi Lars,

So in this case you used tools within Radiance or graphical
interfaces which are running Radiance on the back? I've seen that
Rhyno isn't free, so I would like to try with Daysim and some Python
scripts to try to simulate my system. According to old posts in the
mailing list this should work, am I right? Any suggestion avbout it?

Thanks, Stefano