Viper fatal error with openings?

Hello Diva staff,

I get an error with Viper wich i can't solve:

If i launch the IDF with the EPlaunch the analysis run smooth untill it stops suddenly and the error notepad says:

** Severe ** GetHTSubSurfaceData: Surface Openings have too much area for base surface=ZONE1_FACE_142
** ~~~ ** Opening Surface creating error=ZONE1_FACE_142_WINDOW_1_WINDOWFACE_3

And then it reports a fatal error.

I checked the opening but they look fine to me, i don't know what to do, below there's the model:

I have to say that the shape is a super simple polygonized metaball from the software Houdini, maybe is this one the problem but if i delete the openings works fine, besides this issue happened also other times with breps from Rhino...

I attach the error report, can be useful.

Thanks as usual!

Stefano///

Attachments:

Project_Metaball_Houdini_Pol_V01.err, 2 KB

Replies to This Discussion

Permalink Reply by Mostapha Sadeghipour Roudsari on November 11, 2012 at 3:42pm

Hi Stefano,

This error happens when the area of the subSurface (window) is bigger than your base surface (wall). You can visualize your idf file in CAD using EPLaunch and check the exported geometry.

Besides that, the error file shows the normal direction of the opening surfaces and the normal direction of the base surfaces does not match.

Nevertheless, I'm not sure how accurate the result of your energy simulation will be. As far as I know Viper exports the geometry as a single zone with no perimeter zones might make a big difference in case of simulating a geometry similar to yours.

Best,

Mostapha

Permalink Reply by stefano vafiadis on November 12, 2012 at 4:32am

Hi Mostapha,

Thanks for the reply,

I tried to flip the normals of the glazings and now i get "only" 2 severe errors, then i checked the geometry on the dxf output but no window looked larger than the base surface, most of them are just splitted in various triangle or sub-rectangles!

Then i didn't get the last part of your reply: you mean that with a single thermal zone my analysis wouldn't be so accurate?

I attach in case you would like to read the new error log.

Thanks again,

Stefano///

Attachments:

Project_Metaball_Houdini_Pol_V01_2.err, 1 KB

Permalink Reply by Mostapha Sadeghipour Roudsari on November 12, 2012 at 9:21am

Hi Stefano,

Something is going wrong with the vertices of FACE_204. It might be the order of the vertices. EnergyPlus cannot calculate the area of this face:

"** Severe ** GetSurfaceData: Zero or negative surface area, Surface=ZONE1_FACE_204"

and then whatever subSurface you have will have a bigger area than zero! That' whay you get:

** Severe ** GetHTSubSurfaceData: Surface Openings have too much area for base surface=ZONE1_FACE_204

** ~~~ ** Opening Surface creating error=ZONE1_FACE_204_WINDOW_2_WINDOWFACE_1

Do you want to upload the .idf file so I can take a look at it later today.

Correct! I wonder if your geometry should be modeled as multiple zones. Back to the zoning I suggest you to read Getting Started with EnergyPlus document in case you haven't already read it.

Best,

Mostapha

Permalink Reply by stefano vafiadis on November 12, 2012 at 10:23am

Dear Mostapha,
I understand quite all but is there a way to isolate this FACE_204 and study it's case? I looked all day long how to isolate it without succeeding, even the geometries of the dxf file doesn't have any trace of Energy Plus name tagging of all faces: would be great to know wich one is the famous "face 204"!
I will read the getting started doc as you suggest, lovely idea, and in the meantime, if you like, i send you the .idf file.

Thanks again and again, you help is much appreciated!

Stefano

Attachments:

Project_Metaball_Houdini_Pol_V01.idf, 486 KB

Permalink Reply by Mostapha Sadeghipour Roudsari on November 12, 2012 at 11:14am

Hi Stefano,

I'll check your file later today. Can you please run the idf file that you uploaded here and upload the error for the uploaded file as well. I guess the naming order changes each time so FACE_204 is not always the "famous" face that you are searching for. I don't have EnergyPlus 7-0-0 on my system so I cannot run it myself.

Nevertheless, if you want to find the surfaces by name you might use OpenStudio (http://openstudio.nrel.gov/). Import your .idf file and then use search to find the surface by name.

Mostapha

Permalink Reply by stefano vafiadis on November 12, 2012 at 11:46am

Ok, thanks a lot,

Here's the error log i get running the .idf i just gave you...

The Open Studio solution look very great even if you guess that the names changes every time. Anyway i'm already downloading it, i chose the Windows version and not the Sketch Up one, i hope it's the more user-friendly!

Cheers,

Stefano

Attachments:

Project_Metaball_Houdini_Pol_V01_3.err, 1 KB

Permalink Reply by Mostapha Sadeghipour Roudsari on November 12, 2012 at 3:15pm

Hi Stefano,

1. I checked your .idf file and FACE_204 in this file has no opening!

2. I installed EP-7 and ran the simulation. It worked and I have the results. I attach the error file FYI. As you can see there are some warnings about the angle of the Roof/Ceiling.

3. Here is how your model look. You can see where the warnings come from.

Are you sure you are running the same model?

Mostapha

Attachments:

Project_Metaball_Houdini_Pol_V01.err, 5 KB

Permalink Reply by stefano vafiadis on November 12, 2012 at 4:21pm

Hey Mostapha,

I think I overwrited the .idf with this model while i was trying different solutions! Sorry, now i posted the right one and i checked the dxf file before!

Anyway the analysis of this geomtery, wich you did apparently easy in my case was very slow and only for exterior solar calculation, that's why i adopted that ugly but super simple polygon geometry you can see in the other cases...

Well thanks again and sorry for the wrong idf...

Attachments:

Project_Metaball_Houdini_Pol_V01.idf, 233 KB

Permalink Reply by Mostapha Sadeghipour Roudsari on November 12, 2012 at 11:20pm

Hi Stefano,

So you had duplicated glazing on FACE_204. I regenerated your "Favorite" surface from the EnergyPlus file. Check the attached GH and Rhino file.

I also made the lines of the duplicated glazing as comments in your idf file. It should be fine now.

Mostapha

Attachments:

Stefano_duplicate_Window.3dm, 84 KB
stefano.gh, 18 KB
Project_Metaball_Houdini_Pol_V01_1_msr.idf, 233 KB

Permalink Reply by stefano vafiadis on November 13, 2012 at 4:51am

Hi Mostapha,

Unfortunately the ghs file does not open, it reports an error message with: "ref object not set to an istance of an object".

I tried your idf with EP Lanuch file and it works! Is there a way to bring it to Grasshopper?

Thanks a lot for everything, i really appreciate it, you had been so kind and make me understand more Energy Plus...

Stefano

Permalink Reply by Mostapha Sadeghipour Roudsari on November 13, 2012 at 7:18pm

Hi Stefano,

I guess you are using an older version of GH and that's why you can't open the file. I just opened the vertices to redraw the faces. Here is a screen capture: