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2020-01-30 11:11:39 -0500 answered a question Energyplus 8.8 transition

This issue is being addressed here: https://github.com/NREL/EnergyPlus/pull/7730

2018-04-25 10:48:46 -0500 commented answer GLHE with Energy plus file

Basic information about the ground heat exchanger you want to design; pipe sizes, HX configuration, soil and grout prope

2018-04-25 10:45:34 -0500 received badge  Editor (source)
2018-04-25 10:45:34 -0500 edited answer GLHE with Energy plus file

No, not currently. GLHEPro has been able to write the IDF file objects for EnergyPlus, but the reverse is not supported.

2018-04-24 13:33:54 -0500 commented answer GLHE with Energy plus file

Not automatically. You can manually extract the data from the IDF file and enter it manually, but there are no methods a

2018-04-22 08:30:50 -0500 answered a question GLHE with Energy plus file

No, not currently. GLHEPro has been able to write the IDF file for EnergyPlus, but the reverse is not supported.

2015-07-07 20:11:37 -0500 answered a question The two ground heat transfer models in EnergyPlus

There are currently no published studies comparing the models, however, there is a masters thesis coming out this summer that compares the models. Once that is out, we will work on getting some other peer-reviewed studies published.

Here is some preliminary data from the unpublished masters thesis comparing the slab preprocessor method against the ground-coupled method for a Chicago location. Under ideal conditions with no variations in zone conditions (no windows, constant zone temp), the models perform similarly. But when windows are added, the slab method overestimates heating loads by 18% and underestimates cooling loads by 21% compared to the coupled model.

For a house with no windows but with a floating zone temperature, the floor heat flow predictions are 15% lower with the Slab preprocessor method.

As of right now we are seeing good comparisons between different tools. There are some differences in results between the preprocessor method and the groud-coupled groundDomain method, which we believe are expected due the differences in the methods.

I would have to look into whether we have seen larger temperature swings with the ground-coupled method. I'm not aware of it as of right now. Regarding the effort spend on improving the preprocessor method, I'm not sure I'm aware of that either, but maybe we're thinking of two separate things. In the original post you cite here there is reference to improving the preprocessors, but the ground-coupled method is separate from them so that reference is not correct. There may have been other workflow improvements but I don't think they relate specifically to the preprocessors.

I'm not expecting there to be any additional work on the preprocessors. Once these models start getting some use and people are comfortable with them, the preprocessors will likely go away. Or at least make them to be downloaded separately.

One disclaimer: from this testing work, there were a few recommended modifications to the code which will make their way into the next E+ release. They are currently sitting on a branch waiting to be merged in. Let me know if you want a version with those changes incorporated. (I think thats OK, unless someone on the EPDT tells me otherwise). Let me know if you have any other questions.

Edit: This version would only be appropriate testing purposes due to lack of transition support.

2014-09-23 15:13:34 -0500 received badge  Teacher (source)
2014-09-23 12:21:10 -0500 answered a question Ground Contact Slab Modeling

The OSU ground-coupled slab model will be released with EnergyPlus V8.2 in a couple weeks. This model allows users to model the ground coupled heat transfer directly by setting up a ground domain and setting the ground-coupled surface's other side conditions to interact with the ground domain. The preprocessor is no longer needed with all code being incorporated into E+ and the zone and ground simulations occurring simultaneously.

A similar basement model will be released with the next full E+ release, but it will also be available much sooner in an incremental release once we have it finished up.