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Tips on how to make a big model run quicker

asked 2016-06-09 05:19:06 -0500

TomB's avatar

updated 2016-06-10 16:48:18 -0500

I am working on a simple model, with a large number of zones. It's a 4 story hotel.

Are there any ways of making the SketchUp plugin run a bit quicker? Can I delete the OpenStudio - Loose Geometry and Space Diagrams?

I am aware of zone multipliers for speeding up the e+ simulation but I chose not to use those. Are there any tips for making the OS App run a bit quicker?

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How many zones do you have? Are you having difficulties in both the Sketchup Plug in and the OS App? Tabs such as Space, and Loads will necessarily be a bit slow but it shouldn't affect the HVAC tab for example.

Julien Marrec's avatar Julien Marrec  ( 2016-06-09 07:01:00 -0500 )edit

555 zones ! Ouch. the slowness seems reasonable for the excessive number of zones. The sketchup app is slow, but functioning. The spaces tab in the OS App is slow but functioning. I'll stick to Ideal Air Loads.

TomB's avatar TomB  ( 2016-06-09 07:30:56 -0500 )edit

That's a gazillion! I'd strongly advise for multipliers :) Simulation time will be awful too

Julien Marrec's avatar Julien Marrec  ( 2016-06-09 08:04:22 -0500 )edit

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answered 2016-06-10 11:20:59 -0500

updated 2016-06-10 11:22:02 -0500

When use "Project Loose Geometry" or "Create Spaces From Diagram" that geometry is put onto a non-visible layer in SketchUp, but is never saved in the OSM file. If you quit SketchUp and re-open the OSM (without also loading a SKP file) they should be gone, but that probably isn't why you are seeing performance issues. As @Julien Marrec mentioned this is a large model.

Here are a few general SketchUp Plugin tips to make sure you get the best performance

  • Make sure the Outliner window isn't open
  • Don't turn on Shadows
  • Keep the line style simple
  • If you have been in a SketchUp session for days, quit and then re-start SketchUp

Tips for large model in OS app

  • Multi select helps, but on a very large model it will still have slower performance. If you want to for example apply ideal air loads to all zones, use a measure that can be run using "Apply Measures Now".
  • Also as @Julien Marrec mentioned avoid tabs you don't need to go to, in particular ones like spaces, zones and surfaces which will have tons of objects in your model.

I do think it is worth looking at the building you are representing to see if 500 zones are necessary, same for the number spaces, surfaces, and sub-surfaces. Developing the skill to abstract your model so it isn't too big but still provides enough detail for an 'accurate' energy model takes time but is invaluable and will save you tons of stress and sleep.

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Why is saving sleep a good thing?

__AmirRoth__'s avatar __AmirRoth__  ( 2016-06-10 14:49:24 -0500 )edit

Thanks for the answer David. I'll ask another question on how to abstract the model and make use of multipliers

TomB's avatar TomB  ( 2016-06-10 20:20:11 -0500 )edit

Well, maybe save stress and enable sleep :)

David Goldwasser's avatar David Goldwasser  ( 2016-06-11 22:51:31 -0500 )edit

@David Goldwasser what happens when 500 zones isn't a large model? It's fairly standard for my projects, so I build measures to handle that scale. Are there opportunities to enhance the OS app to handle this size model? Floor multipliers add significant uncertainty, because we don't have repetitive floor plates. Often times, this simplification adds more complexity to the process than dealing with the model scale.

Interestingly, the "Measures" tab is loading slowly in one of my models. Would scale affect that?

jmcneill's avatar jmcneill  ( 2016-06-30 15:47:11 -0500 )edit

@jmcneill what kind of measures are in your workflow? If you have EnergyPlus measures we forward translation the OSM to an IDF file for use with user arguments, which could slow it down. If you have a really big model, I would try and avoid the plugin more than necessary, as well as the spaces or at least the surfaces sub-tab in the OpenStudio application. Also try to use measures to automate tasks when you can. One concept that could be used is to store all of the space/zone data in an Excel file and have a measure push to the OSM.

David Goldwasser's avatar David Goldwasser  ( 2016-06-30 16:31:46 -0500 )edit

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Asked: 2016-06-09 05:19:06 -0500

Seen: 461 times

Last updated: Jun 10 '16