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2017-06-07 07:42:04 -0500 received badge  Teacher (source)
2017-06-06 23:47:34 -0500 answered a question How to Model Inset Windows

I have done simulations like these by using option B, but with one extra setting in the idf: Just set an Output:Diagnos

2016-11-17 02:25:54 -0500 received badge  Supporter (source)
2016-11-17 02:25:52 -0500 commented answer Modelling large volumes like industrial halls

Thanks for the hint, I haven't been looking at those models in detail until now. I'll conduct some tests to see how that works out... What about horizontal divisions of large spaces? Do you use the air-wall approach with zone mixing? Or would it be more accurate to use the airflow network with huge openings as an approximation to get the exchange of air between the different parts (somewhat) right?

2016-11-06 10:44:57 -0500 received badge  Student (source)
2016-11-06 08:13:36 -0500 asked a question Modelling large volumes like industrial halls

Hi everyone!

Recently, an architect asked me if I could run a thermal energy simulation for a large industrial hall in order to accurately determine heating and cooling loads for the HVAC systems, because he was asked by his client (they've had some problems with badly sized HVAC systems in the past). I told him that in such cases a building energy simulation probably wouldn't be the best idea, because of the huge air volume on the one hand and typically local heat sources from machines etc. as well as local cooling/comfort requirements on the other hand. With the assumption of perfectly mixed room air, the local effects can't be taken into account the way they should be. So you would have to divide the hall in several parts, both horizontally and vertically in order to try and capture these effects, but I don't really feel comfortable doing that.

My first advice was to conduct a CFD analysis for one or more design conditions as cooling loads in production halls are typically driven by (relatively constant) internal sources.

Has anyone performed energy simulations for such kinds of buildings? What are your experiences? How do you usually deal with dividing a large zone into smaller zones, do you make use of air-walls much? What about vertical stratification?

Looking forward to reading about your thoughts on the topic...