Error exporting to GBXML

Rhino Plugin
1

Hello,

I am trying to build a geometry based on the manual being given on the website.
But everytime I export it into GBXML file, there is always an error showing up like the attached image.

Does anyone know what’s causing this?

error
error1194×682 232 KB

2

error2
error2868×625 33.1 KB

this is geometry, just in case you need to see it

3

Hi @ricardolionar,

Based on the error, you’re model is using the wrong units. If I have to guess it’s currently mm but it should have been meters.

Can you change the units and try again?

If that didn’t work, can you share the Rhino file with us?

4

Hi @mostapha

Yes, I am using mm in Rhino, but the error still happens if I am using a meter
For context, I am trying to simulate a small structure instead of a big building. But the error still happened even if I scaled up my model
It still produced the gbxml, but not sure if the error affected the outcome…
(I am trying to use it in DesignBuilder)

Kindly let me know if I missed something in the process…
test_draft.3dm (434.6 KB)
Thank you

5

@ricardolionar, the model is still not correct. The total height of your building is 76 cm.

image
image1107×895 166 KB

Make sure you scale the model to the correct dimensions before exporting the model.

You should also check if your model is valid before trying to export it as a gbXML. It currently has several validation issues.

image
image1529×938 166 KB

6

Hi @mostapha ,

Thanks for checking it out. The model size is indeed correct. I’m examining parts of the building components, not the entire building. I’m treating this small part as a “zone” to see if the EnergyPlus simulation is accurate.

I understand that most Building Energy Simulations are typically done for entire buildings. However, I wanted to experiment and see whether Honeybee or DesignBuilder, both of which utilize EnergyPlus, are the right tools for this task.

The first step is to export the model to GBXML since DesignBuilder doesn’t allow me to model tiny parts, whereas Rhino does.

I would appreciate any suggestions you might have.

Regards,
Ricardo

7

Hi @ricardolionar,

I’m a bit confused. It is fine if you want to test part of the building. There is no such limitation in energy modeling tools. You can start with a single room. Just make sure the dimensions are realistic. A room is most likely taller than 0.75.

Also, the thermal zones should not be modeled on top of each other regardless of the size of the model.

8

Thanks, @mostapha
Sorry if I was not clear enough. So when I said part of the building, it is just a part of the wall assembly like this

tested part
tested part1075×858 49.5 KB

If the facade has a cavity inside it, I treat it as a “thermal zone” so that I can find out the cavity temperature. I did this because I wanted to verify the result I get from the actual experiment (which also used the same size).

That is the main idea. But not sure about the accuracy, since most people use the building energy simulation for measuring the full size of the building.
If it is not working or the accuracy is questionable, I may have to switch to finite element modelling. But the workflow will be slightly more complex…

Regards,
Ricardo

9

Hi @ricardolionar, thank you for sharing the screenshot. In EnergyPlus the smallest unit of calculation is an isothermal zone. There are methods for modeling vertical cavities but it might not fit your needs.

See these links: