external shading

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Michi
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external shading

Post by Michi »

Hello again,

I am would like to calculate the performance of the room with and without external shadings. (I din't use the "percentage profile group")

When I apply it and I change the data, I can see differences in the energy performance.. and this is of course what I expected.

But I cannot see any changes in the daylight illuminance. Why?
Which parameters should I check to see the effects of the external shading on the daylight of the room?

Thank you very much!
enerGwizz
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Re: external shading

Post by enerGwizz »

There are a few different ways to model external shading, but since you mentioned "percentage profile group," it looks like you're modeling the shading as a device in the external glazing construction.

If specifying the shading causes your energy consumption to be reduced, then it seems to be working. In order to calculate daylight illuminance values on a grid, you'll need to be using the FlucsDL or RadianceIES modules. In order to get values back into your Apache simulation, I think you NEED to use Radiance and place daylight sensors in the spaces. I think it's the daylight sensors that use the "daylight illuminance 1" and "daylight illuminance 2" room variables.

But for what it seems like you're after, I would just run a daylight simulation (FlucsDL) before and after the shading devices get entered, and you can visually see the changes in light entering the space. Since the construction inputs in the daylight modules are a little different than in Apache, you may run into a case where the shading devices need to be modeled using a geometry, but it may work fine as you're doing it.

I'm not an expert, but this is my understanding of the software so far. Hope it helps..
Michi
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Re: external shading

Post by Michi »

Thank you very much enerGwizz..

just to clarify.. every time I change something in the geometry or (like now) in the windows characteristics.. before simulating in ApacheSim.. I should go in RadianceIES and make the simulation "apache" using sensors?

Now I am trying to see if with FlucsDL the changes are visible!
Thank you very much for the suggestion!
Michi
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Re: external shading

Post by Michi »

Sorry to say.. but nothing changed.

I did the simulation in FlucsDL, then the sensors in RadianceIES and then ApacheSim, both with and without external shadings.

The daylight illuminance and daylight factor does not have any changes.

The only results that have en effects are the energy consumptions for boiler and chiller.

If you have any other suggestion that I can try to simulate the exact illuminance in the room with external shading it will be really nice.

Thank you very much!
KasperS
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Re: external shading

Post by KasperS »

Hello

I know nothing about FlucsPro, but if you want to use Radiance to calculate this, you have to create the shadings in the ModelIT, because radiance doesnt take what you type in the windows into account. Also to get the right light transmittance of the windows you have to change the external glazing value in the Radiance.

Kasper
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PCully
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Re: external shading

Post by PCully »

Hi,

When using the Radiance link between Apache and Radiance sensors you'd also have to create profiles referencing the Radiance sensor results otherwise it would have no impact.

I'm slightly suspicious you see energy changes but no change directly related to light coming in the room, what about solar gain for the room? That may show the effect of the shades better in the context of the sim

Phil
IES Worldwide Technical Support
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