2020 07 29_meeting - lbl-srg/soep GitHub Wiki

Date: July 29, 2020, 8:15am-9am Pacific Times

The purpose of this meeting is to coordinate the Modelica integration for SOEP.

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1. Previous action items.
2. SimBuild presentation.
3. Release of Spawn coupling.
4. Kyle, Michael: Refactoring room air heat and mass balance.
5. Kyle, Michael: EnergyPlus I/O variables.
6. Michael, Kyle: Support for radiant systems.
7. Stuart: FMI-QSS.
8. Kyle, Michael: Optimica license protection.
9. Jianjun: JSON representation for OS front-end to Modelica
10. Other items

Draft slides submitted to ASHRAE by 8/5/2020 for review. (15-20 min, with questions afterwards.) Need 1 to 2 slides max about QSS, compilation toolchain, OPTIMICA. (Mention software names once only.)

See milestones. Should we only support for now Linux?

Branch issue1129_energyPlus_zone works for multiple buildings for JModelica, Dymola and OpenModelica.

Issues are at https://github.com/lbl-srg/modelica-buildings/issues?q=is%3Aissue+is%3Aopen+label%3Aspawn

Next, work on

• Kyle to correct wrong radiation temperature, https://github.com/lbl-srg/modelica-buildings/issues/1954
• Michael to add validation for schedules and EMS actuators, https://github.com/lbl-srg/modelica-buildings/issues/1633
  • Kyle to fix blocker: https://github.com/lbl-srg/modelica-buildings/issues/2002
  • Kyle to look at blocker: https://github.com/lbl-srg/modelica-buildings/issues/2000 (Kyle either fixes it, or proposes new wording for https://lbl-srg.github.io/soep/softwareArchitecture.html#sending-input-to-energyplus)
• Kyle to provide description for user guide for how warmup works. (Email from May 5, 2020).
• Kyle to add filter level of info/error/fatal errors. See code near const size_t nCat = fmi2_import_get_log_categories_num(bui->fmu); (Pending since October 2019)
• Kyle to look into numerical instability (walls may be initialized to wrong temperature). See for example Experimental/EnergyPlus/Examples/VAVReheatRefBldgSmallOffice/FloorOpenLoop or Experimental/EnergyPlus/Validation/OneZone and set the initial room temperature to 10 degC. (Pending since Nov. 2019)
• Kyle to provide list of supported output variables, and statement of how non-supported output variables are handled, https://github.com/NREL/Spawn/commit/e443d634ab4f15d5d69e487fcc206c7d4f403353
• Michael/Milica to use thermal zones in larger model, https://github.com/lbl-srg/modelica-buildings/pull/1663
• Kyle to move model.spawn to resources folder. It has the same information as ModelicaBuildingsEnergyPlus.json (other than that some path are absolute and some are relative in model.spawn).
• Kyle to look into generating all outputs in the folder tmp-simulation-TwoIdenticalZones. Also avoid multiple copies, for example, tmp-simulation-OneZone.building has most files twice, including the binaries (total 183 MB).

Need to refactor to freeze room air temperatures at initial temperature as requested from Modelica. Rooms not in Modelica will do warm-up to compute their room temperature. Warm-up stops when all inside-facing surface temperatures stabilized at mid-night in all rooms, whether present or not in Modelica.

Goal was to have a Buildings library release with Spawn before the peer-review.

LBL AOP 6/30: Couple controls I/O. (Blocked, see above.)

LBL AOP 9/30 (go/no-go): Release that can couple Modelica-based control to E+.

Kyle to work on emitting all EnergyPlus objects that are supported by Spawn.

1. If there is a thermal zone in Modelica, then there need to be a Zone object in the idf file. Otherwise the simulation stops with an error. EnergyPlus reports a Fatal Error to its error file and to the FMI API call.
2. If there is an Zone object in the idf file but no thermal zone in Modelica for this EnergyPlus zone, then EnergyPlus simulates the zone using free floating temperature. There is no HVAC system, but may be internal gains. EnergyPlus reports an information message to its error file and to the FMI API call.
3. All HVAC objects in the idf file will be removed by the Spawn executable before it writes the idf file to the FMU.
4. For the EnergyPlus envelope, either the CTF transfer function or the finite difference method can be used.
5. Output variables and EMS actuators need not be present in the idf file.

Specfication at https://lbl-srg.github.io/soep/softwareArchitecture.html#coupling-of-a-zone-surface.

To be done in FY 21.

Binning is working. Stuart to work on more test cases of Buildings library. Parallization is not promising at least for the current size of models.

xml file does not have all event indicators for discrete variables that are not continuous state.

Binaries are also posted for OS X and Windows. These can be pulled into the Buildings library (first for Windows).

No discussions.

No discussions.

To do:

• Address TypeError issues reported in https://github.com/lbl-srg/modelica-json/issues/106.
• Handling replaceable models.

None.

Michael to add issue about "numerical instability" above.

Michael to keep working with Modelon on making dp of pressure drop elements a state rather than p using stateSelect.