DGP calculation in Daysim

radiance-daysim
1

Hi folks!

I'm trying to calculate the annual DGP profile using Daysim but I'm having
troubles setting the right Viewpoint File. I'm using the advanced dynamic
shading model. I think to have properly set the shading device geometry and
material since Daysim can calculate illuminances for both up and down
shading status. At the end of the simulation the .dgp file is empty.

Can anyone help me?

Thanks a lot!

Cheers,

Silvia

arch. Silvia Cammarano

PhD student in Energetics

Politecnico di Torino

DENERG: Department of Energy

Corso Duca degli Abruzzi, 24

10129 Torino

Italy

office: +39 0110904410

fax: +39 0110904499

skype: silvia.cammarano

www.polito.it/tebe

2

Hi Silvia,

the viewpoitfile must have the same format as a viewpoint file for rpict or rvu (*.vf). Multiple lines correspond to multiple calculation points.
Hope that helps, if not, is there any error message?

good luck,
Jan

···

Am 2013-10-23 18:01, schrieb Cammarano Silvia:

Hi folks!

I'm trying to calculate the annual DGP profile using Daysim but I'm
having troubles setting the right Viewpoint File. I'm using the
advanced dynamic shading model. I think to have properly set the
shading device geometry and material since Daysim can calculate
illuminances for both up and down shading status. At the end of the
simulation the .dgp file is empty.

Can anyone help me?

Thanks a lot!

Cheers,

Silvia

ARCH. SILVIA CAMMARANO

PHD STUDENT IN ENERGETICS

Politecnico di Torino

DENERG: Department of Energy

Corso Duca degli Abruzzi, 24

10129 Torino

Italy

office: +39 0110904410

fax: +39 0110904499

skype: silvia.cammarano

www.polito.it/tebe

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

3

Hi Jan,
thank you very much for your reply.
Yes, I used a .vf file format with two calculation points (two lines).
The calculation at the end works but it's very slow. I'm using the advanced dynamic shading device model, the time-step is 15 minutes and the Radiance parameters are: ab = 5; ad = 1000; as = 20; ar = 300; aa = 0.1.
During the simulation some warnings about the vertical illuminance below 100 lux (out of range for DGP calculation) or low brightness scene appear.
Do you think I should change the Radiance parameters to have a faster calculation?

Silvia

arch. Silvia Cammarano
PhD student in Energetics

Politecnico di Torino
DENERG: Department of Energy
Corso Duca degli Abruzzi, 24
10129 Torino
Italy

office: +39 0110904410
fax: +39 0110904499
skype: silvia.cammarano

www.polito.it/tebe

-----Messaggio originale-----
Inviato: mercoledì 23 ottobre 2013 19:07
Priorità: Alta

Hi Silvia,

the viewpoitfile must have the same format as a viewpoint file for rpict or rvu (*.vf). Multiple lines correspond to multiple calculation points.
Hope that helps, if not, is there any error message?

good luck,
Jan

···

Da: Jan Wienold [mailto:[email protected]]
A: [email protected]; DAYSIM discussion
Oggetto: Re: [Radiance-daysim] DGP calculation in Daysim

Am 2013-10-23 18:01, schrieb Cammarano Silvia:

Hi folks!

I'm trying to calculate the annual DGP profile using Daysim but I'm
having troubles setting the right Viewpoint File. I'm using the
advanced dynamic shading model. I think to have properly set the
shading device geometry and material since Daysim can calculate
illuminances for both up and down shading status. At the end of the
simulation the .dgp file is empty.

Can anyone help me?

Thanks a lot!

Cheers,

Silvia

ARCH. SILVIA CAMMARANO

PHD STUDENT IN ENERGETICS

Politecnico di Torino

DENERG: Department of Energy

Corso Duca degli Abruzzi, 24

10129 Torino

Italy

office: +39 0110904410

fax: +39 0110904499

skype: silvia.cammarano

www.polito.it/tebe

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

4

Hi Sylvia,

can you determine, what the "bottleneck" is? is it the illuminance calcualtion at the beginning or the image calculation?
I guess you made also normal illumianance calculations first - how long did they take?
If the illuminance calc is the bottleneck, then the ambient parameters reduce the time. but you are already at a low limit, especially regarding ad and as.
In general it is more important to have a high ad than having a very low aa. So I would say you could incread aa to 0.2. But I usually calculate ad with 8192 or double... - this increases the time then again.
The ambient parameters effect only the illuminace calculation in the first step - the calculation of the images is using ab 0 and cannot be changed by the user.

I guess you are using windows which is in general a problem, since it is not possible right now to use more than one cpu at the same time. I have a linux version running here and usually distribute jobs to 10-40 cores...

best regards
jan

···

On 10/25/2013 01:36 PM, Cammarano Silvia wrote:

Hi Jan,
thank you very much for your reply.
Yes, I used a .vf file format with two calculation points (two lines).
The calculation at the end works but it's very slow. I'm using the advanced dynamic shading device model, the time-step is 15 minutes and the Radiance parameters are: ab = 5; ad = 1000; as = 20; ar = 300; aa = 0.1.
During the simulation some warnings about the vertical illuminance below 100 lux (out of range for DGP calculation) or low brightness scene appear.
Do you think I should change the Radiance parameters to have a faster calculation?

Silvia

arch. Silvia Cammarano
PhD student in Energetics

Politecnico di Torino
DENERG: Department of Energy
Corso Duca degli Abruzzi, 24
10129 Torino
Italy

office: +39 0110904410
fax: +39 0110904499
skype: silvia.cammarano

www.polito.it/tebe

-----Messaggio originale-----
Da: Jan Wienold [mailto:[email protected]]
Inviato: mercoledì 23 ottobre 2013 19:07
A: [email protected]; DAYSIM discussion
Oggetto: Re: [Radiance-daysim] DGP calculation in Daysim
Priorità: Alta

Hi Silvia,

the viewpoitfile must have the same format as a viewpoint file for rpict or rvu (*.vf). Multiple lines correspond to multiple calculation points.
Hope that helps, if not, is there any error message?

good luck,
Jan

Am 2013-10-23 18:01, schrieb Cammarano Silvia:

Hi folks!

I'm trying to calculate the annual DGP profile using Daysim but I'm
having troubles setting the right Viewpoint File. I'm using the
advanced dynamic shading model. I think to have properly set the
shading device geometry and material since Daysim can calculate
illuminances for both up and down shading status. At the end of the
simulation the .dgp file is empty.

Can anyone help me?

Thanks a lot!

Cheers,

Silvia

ARCH. SILVIA CAMMARANO

PHD STUDENT IN ENERGETICS

Politecnico di Torino

DENERG: Department of Energy

Corso Duca degli Abruzzi, 24

10129 Torino

Italy

office: +39 0110904410

fax: +39 0110904499

skype: silvia.cammarano

www.polito.it/tebe

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

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

--
Dr.-Ing. Jan Wienold
Head of Team Passive Systems and Daylighting
Fraunhofer-Institut für Solare Energiesysteme
Thermal Systems and Buildings
Heidenhofstr. 2, 79110 Freiburg, Germany
Phone: +49(0)761 4588 5133 Fax:+49(0)761 4588 9133
[email protected]

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