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Open Studio won't load the DDY file

asked 2014-11-12 06:02:07 -0500

cesar8's avatar

updated 2014-11-12 09:59:59 -0500

I have a model created with Open Studio, version 1.5.0. I import this model in 1.5.1 and it was still running, but upgrading on the beta 1.5.2 version, Open Studio won't load DDY file (after I select the DDY, it disappear when I shift to another tab). Now the problem is I have a newer .osm model , and only the older version of the program working. I try to uninstall and reinstall. I try to edit the .osm change the version tag form 1.5.2. to 1.4.0, without results. I know that I was really foolish to run my .osm with a testing version, but ...that has happened , and that file costs a week of work. Please help ! Cesare

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Hi cesar8, I ve encountered the same problem...

piercloud's avatar piercloud  ( 2014-11-12 06:23:34 -0500 )edit

@cesar8. (and everyone else) if you have a software specific question, please add the name of the software as a tag so that it routes to the right people.

__AmirRoth__'s avatar __AmirRoth__  ( 2014-11-12 07:13:32 -0500 )edit

@cesar8 - suggest removing the NREL tag as that's too general. I replaced "nrel" tag in your natural ventilation post.

MatthewSteen's avatar MatthewSteen  ( 2014-11-12 07:56:25 -0500 )edit

@piercloud - this is more of a comment, please edit to include an answer or delete, thanks.

MatthewSteen's avatar MatthewSteen  ( 2014-11-12 08:05:36 -0500 )edit

@cesar8 (and everyone else). The name of the software (e.g., openstudio) is enough. The OpenStudio development team (some of whom are not at NREL) is subscribed to that tag and get new questions via email.

__AmirRoth__'s avatar __AmirRoth__  ( 2014-11-12 09:36:32 -0500 )edit

3 Answers

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answered 2014-11-12 08:37:44 -0500

updated 2014-11-12 08:53:46 -0500

OpenStudio has some confusing behavior with design days. When you select a ddy file, OS will grab the design day objects in that file and import them into the osm. The path that you see in the "DDY File Path" field is a remnant of what you selected, but that path is no longer important and it is not kept with the model. What is important is the "number of design days" listed in the bottom row. I'm guessing your model still has design days and will still run in 1.5.2. Have you tried it?

What is new in OpenStudio is that we no longer keep all of the tabs open in memory while you are working on a Model. Instead only the tab that you have selected is held in memory. We did this to improve the application's performance and to a lesser extent the memory footprint. It means that when you click on a new tab the old tab is gone, and when you come back it has to be reinitialized with the Model data. Since the DDY File Path is not actually data that is stored in the model, that path is gone. This same thing has always happened when you closed a Model and later reopened it.

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Thank you very much, Kilie. I re-run the simulation and finally I realize that crashs were because of some orphaned objects in HVAC systems . I'm happy to learn that DDY informations are stored in the .osm. Actually I can notate a performance improvement in OS. And yes, "number of design days" and location's informations are listed in the bottom rows. My .osm is still working in OS1.5.2.

cesar8's avatar cesar8  ( 2014-11-14 06:04:48 -0500 )edit

answered 2015-07-27 16:16:27 -0500

updated 2015-07-27 16:19:13 -0500

Complementing Kyle's answer: there may be cases where OpenStudio indeed does not load ddy DesignDay definitions, although you have specified a valid ddy file path to a ddy file. The reason is that the ddy file does not contain valid DesignDay definitions (or any such definitions). You can verify this by opening the ddy file with a text editor.

In this case OpenStudio also does not show the ddy file path as accepted.

As a recent example I observed this problem with a ddy file for Sant Ana John Wayne Airport (CA), which did not contain DesignDay definitions.

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answered 2015-07-28 09:10:29 -0500

As of OS 1.8.1 the weather tab received an update that provides a lot more information about the DDY data your model is using. Here's a screenshot.

image description

We think this is a big improvement that removes the ambiguity of "the mystery field."

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Asked: 2014-11-12 06:02:07 -0500

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Last updated: Jul 28 '15