NickC's profile - activity

This is another plant equipment operation issue I have been experiencing and was hoping someone could provide an explanation of what is going on here.

I have a pretty standard CHW loop, which has a couple of chillers and three heat exchangers. The heat exchangers go to secondary CHW loops which serve multiple buildings.

Both chillers come on and operate together to meet cooling demands. I set the "Load Distribution Scheme" to "Uniform" in OpenStudio and pressed Play. For each loop (CHW and HW) that I've set to "Uniform", I get the following error.

" * Warning * GetPlant/CondenserLoopData: PlantLoop="CHW LOOP (SECONDARY BLDG 11 AND 12)", Invalid choice. * ~~~ * ...Load Distribution Scheme="UNIFORM". * ~~~ * Will default to SequentialLoad. "

Looks like E+ is changing the Load Distribution Scheme and the behavior of the chillers looks like a sequential load scheme to me. Is this a bug? Am I doing something wrong here? Thanks! -N

Hello UA; I've been working on how best to enter previously simulated building loads onto the main central plant. I know the heating and cooling loads each building requires from the plant loop, along with their flowrate demands, for a typical year. My central plant has the LoadProfile:Plant object inserted in place of the buildings.

What ways do you know of to get the building load wattage and flowrate into the LoadProfile:Plant object? I REALLY don't want to generate a day-by-day schedule for the whole year...

Associated Questions (I'd say) 1 2 3

Some Details: Building configuration

and Buildings 1-3 have already been simulated with district heating/cooling on their CHW and HW building loops.

Lastly, the main building central plant (to be simulated) has LoadProfile:Plant objects for Building 1-3 on both the CHW and HW loops. Shown below are the primary and a representative secondary loop.

Right on @aparker; I updated the post with results from your suggestion regarding the end-use distribution; planning to

@TomB Thanks for the feedback; for both TMY and AMY weather runs I adjusted the start day accordingly; it seems like odd

@TomB Thanks for the questions; for both TMY and AMY weather runs I adjusted the start day accordingly

@Liam Using the full set (7 total) of sizing days and kept them consistent between all simulations; I also checked the E

Unexplained start date sensitivity in E+ Simulation For the attached model, differences in monthly total electric energy

Unexplained start date sensitivity in E+ Simulation For the attached model, differences in monthly total electric energy

Unexplained start date sensitivity in E+ Simulation For the attached model, differences in monthly total electric energy

I am aware of the RDD and MDD output files for a given E+ run. It would be helpful from a programming POV to have a complete list of all the possible outputs that can be provided by E+, along with the associated E+ object for each output. Like the Input Data Dictionary (IDD) file...maybe an ODD file?

For reference: http://bigladdersoftware.com/epx/docs...

Is the a comprehensive E+ output list? I am aware of the RDD and MDD output files for a given E+ run. It would be helpfu

Is the a comprehensive E+ output list? I am aware of the RDD and MDD output files for a given E+ run. It would be helpfu

@rraustad I believe we've just run into the same issue as the OP referenced in the thread; significantly increased simul

Agreed, seems like it should be allowed from the IO ref. I added some flavor text to the post! Think I set it up correct

Agreed, seems like it should be allowed from the IO ref. I added some flavor text to the post!

Can the Duct E+ object be used to make a AirLoop demand-side bypass? How is the E+ Duct Element typically used? I was co

Can the Duct E+ object be used to make a AirLoop demand-side bypass? How is the E+ Duct Element typically used? I was co

Can the Duct E+ object be used to make a AirLoop demand-side bypass? How is the E+ Duct Element typically used? I was co

Thanks @Eric Ringold; I looked at the two IDFs you mentioned. Seems that the Duct object is used as a component on the A

Thanks @EricRingold; I looked at the two IDFs you mentioned. Seems that the Duct object is used as a component on the Ai

Can the Duct E+ object be used to make a AirLoop demand-side bypass? How is the E+ Duct Element typically used? I was co

Can the Duct E+ object be used to make a AirLoop demand-side bypass? How is the E+ Duct Element typically used? I was co

Thanks for checking! I'm in, looks like it was user error

@Jamie Bull Is this channel/bot still operating? I sent an invite (@gmail acct.) and haven't heard back in 20-30 minutes

Thanks Jamie; I've pinned that repo and will report back if we get time do some testing

@Julien Marrec Thanks for the excellent and detailed answer! The new JSON idd is exciting and I'm following that development now on Github as well.

Thanks Matt/Chandan/Jason! I'm currently using a combination of all three. I plan to cross-reference all three and report back with any findings as an answer

Thanks for the quick suggestions! Both would do the trick; the object link is easier. I'm also looking for the required inputs for each object so the *.idd covers that as well. But I can't choose an answer! ;)

Can anyone guide me to a complete list of energyplus objects for v8.4, v8.5, and v8.6? Aside from the documentation on Big Ladder, I haven't located this list yet. I did check the E+ Github, release notes, and E+ wiki.

I'm looking for something that could be easily incorporated into a database.

@__AmirRoth__ is there any update on the JSON feature development? There was an update that indicated this feature might be released in late 2016

@Julien Marrec Thanks for the advice! Minimum motor freq. is an important feature and hopefully will make it into OS in future releases. For now, E+ it is :)

In practice, it is common for AHU VFD fans to have some set minimum motor frequency. I've been trying to implement this is an OS/E+ model but seem to be stuck (i.e. you need to fix the fan so it never goes below 30 Hz)

@Kyle Benne seems to be asking about this as well...but not sure if he ever got any satisfaction. https://unmethours.com/question/11631...

Anyone know how to accomplish this?

As @JasonGlazer mentioned, Jon Hand has published some work on ARM computing with ESP-r

Thanks for the info Jason!

My general question is related to designing a low-cost/high-throughput E+ computation server (Linux OS) that would focus on running many simulations in parallel. For those familiar with server design, I'm thinking commodity computing versus high performance computing. We run a LOT of simulations at my company. In addition to existing hardware, we're also using web-based resources. Despite the convenience of web-based computing, I'm not certain current options are cost effective at large scale.

Related questions: 1) Is anyone aware of studies related to E+ performance on different hardware? (e.g. AMD vs. Intel, memory, CPU clock speed vs. # of cores) 2) Has anyone conducted E+ simulations on ARM architectures? If so, what was your experience?

Obligatory Star Wars quote: Vader: The Emperor does not share your optimistic appraisal of the situation. Other Guy: But he asks the impossible! I need more men!

Well thanks anyway for trying; bought an ODROID and plan to see what it can do!

@__AmirRoth__ In-house developed b/c of custom needs, blend of Ruby & Python