Problem with Indoor view factor

Hello everybody
I imported an idf file with importIDF and it all went well. It recognizes the zones, but connecting IdoorViewFactor, it viewing the error show in the image below:

I created the model with Sketchup and its plugins, in EP it works all properly. I would like to use Honeybee and Ladybug to create the comfort maps…
I think the error may be that ImportIDF reads OpenBrep. Could be? How can I fix it without re-modeling?
Thanks so much!
Massimiliano Busnelli

It will be hard to help you without the model. Can you share the idf file or an example that we can use to recreate the error?

Hi Mostapha,
Sure!
I have try to re-run IDF file with the specific HB component in GH and the simulation it’s correct. When I use same IDF file with IndoorViewFactor, the component is in error.
thank you so much for your help!
Massimiliano

IDF_to_HB.gh (478.5 KB)
Modello_EP_per_GH.idf (582.9 KB)

@MassimilianoBusnelli,

Open Breps will break the comfort map workflows, unfortunately. That is what is going on in your example here.
The main reason why the IDF importer is bringing in open Breps is because:

  1. It is possible to generate an IDF that does not have a closed zone. E+ fundamentally doesn’t care about zone closure but Honeybee does and view factor calculations to generate MRT for comfort maps definitely do. If you made this IDF with the scketchup plugin for OpenStudio, this probably isn’t the case here but, still, this means that it is just impossible for some IDFs to be simulate-able with the comfort map workflows.

  2. The Import IDF component is still in WIP because it very difficult to write an IDF importer that works for all IDF types and formats. Some EnergyPlus interfaces (ahem* DesignBuilder ahem*) write the IDF surfaces in a format that is so messy that it’s exceedingly difficult to write an importer for them. I know that OpenStudio is generally pretty structured in the way that it writes IDFs, though. Given a little bit of time, I think I could get the code in the IDF importer working for them.

If you can confirm that you generated the file using the OpenStudio plugin for sketchup, I will have a go at seeing if I can get your IDF to import correctly. Otherwise, the IDF might not actually have closed zone geometry or it might just be too messy to import correctly.

1 Like

Thanks for reply Chris,
I use LegacyOpenStudio (today Euclid) for modeling EP zones and surfaces in Sketchup. After using only IDFEditor. I tried with a simple model with the same tools (model I attach to you)

Prova_Sup_L.idf (37.5 KB)

Of course this model works. Only Closed Brep. I wonder if there was a way in GH to “close” the Open Brep …
to use the previous complex model!
Thanks!
Massimiliano

Open and close is a relative concept. You can use showEdges command in Rhino to see the areas that are not closed. It might only be a matter of rounding the numbers which you can do by changing the tolerance of your model.

2 Likes

Hi,
I tried with the command showEdges in Rhino, and I saw that the errors are on the doors!
I chose the last file by adding a port and … it does not work!

Prova_Sup_L_Door.idf (38.4 KB)

The colored edge is the base of door…
You can fix it? :slight_smile:
Thanks!
Massimiliano

P.s. I add complex model image:

I checked the idf file and the values are correct. This is a tolerance issue. A quick fix can be moving the door a little bit in z direction? like 5 cm? That should not affect the results of your simulation but should solve this issue.

1 Like

Hi!
Good idea @mostapha. I tried re-model the complex file with Sketchup and Euclid and I got all Brep closed … But IndoorViewFactor does not work yet, another error:

I attach the .idf file:

Modello_EP_per_GH.idf (582.9 KB)

You can help me? :slight_smile:
Thanks!
Massimiliano

This one is a question for @chris! :slight_smile:

1 Like

@MassimilianoBusnelli,
Ok, yes, now we have hit a different issue now. It seems that none of the EP materials in your IDF have solar reflectances associated with them:

All Honeybee EP materials have a solar reflectance and the comfort maps use this reflectance to estimate the amount of solar radiation that gets reflected off them to hit the occupant and make them feel warmer. I had previously not realized that you could have EP materials without any solar reflectance and I’m not sure what E+ is assuming when you do not specify a reflectance. For now, I added a line of code to assume a reflectance of 0.5 if there are none specified in the original EP materials and this enabled me to run the view factor component:

So you can find a working GH file here:
MoreRobustViewFactor.gh (479.1 KB)

Let me know if you end up finding out what E+ assumes when you have no reflectance and keep me posted if you run into any other issues building comfort maps with your model.

Really, thanks a lot @chris!
I solved the issue of the ViewFactorIdoor component! E+ assumes 0,7 as the default value of solar absorptance:


(by InputOutput Reference)

then 0,3 of solar reflectance…

I then tried to use the components:
. HoneyBee_Read EP Result
. HoneyBee_Read Ep Surface Result
using a path file linked to a .csv file. The goal was to use the outbound variables to be included in the component Honeybee_Adaptive Comfort Analysis Recipe to generate comfort maps.
I simulated in E+ the same file twice (with different names) by compiling these variables:
.Zone Operative Temperature
.Zone Mean Air Temperature
.Zone Mean Radiant Temperature
.Zone Air Relative Humidity
.Zone Air Heat Balance Internal Convective Heat Gain Rate
.Zone Air Heat Balance Surface Convection Rate
.Zone Air Heat Balance System Air Transfer Rate
and the HoneyBee_Read EP Result component function with linked .csv
But the .csv file with this variable:
. surface outside face temperature
. surface inside face temperature
Not function with HoneyBee_Read Ep Surface Result component. See the error in the following image:

I also attach the .gh file:

IDF_to_HB.gh (568.7 KB)

(I do not attach the .csv file because it weighs 120Mb…)

I also tried to simulate the .idf file with the component HoneyBee_run Energy Simulation (the goal was plotting the surface variable), but I got this error:

Can you help me another time?
Thanks
Massimiliano

Hi @chris,
I solved the error that gave me the Honeybee_Read EP Surface Result component.
I did not know I should tell EP to write the subset variables in the .io file. Below the image:

I still have not been able to make comfort maps because I can not understand what to set in E + to write _ZoneAirFlowVol …
I set the ZoneInfiltrationDesignFlowRate class in E+ and wrote the Zone Infiltration Standard Density Volume Flow Rate as variable.
The Honeybee_Read EP Result component does not work and tells me:

1. Solution exception:index out of range: 0

I can not really understand why!
These are the files I use:
Modello_EP_per_GH.eio (27.1 KB)
IDF_to_HB.gh (542.0 KB)
Modello_EP_per_GH.idf (598.9 KB)

@chris @mostapha Can you help me?
Thanks
Massimiliano

I did it!
The problem is that I have to create as many ventilation and infiltration objects as are the zones!
Thanks!
Massimiliano