Splitter inlet flow does not match mixer outlet flow

grasshopper ironbug
,
1

Hello everyone,

I have attempted to model my first HVAC system with ironbug. I am receiving the following error when running a simulation. How do I fix this?

  1. ** Severe ** Plant flows do not resolve – splitter inlet flow does not match mixer outlet flow
  3. ** ~~~ ** Environment=RUN PERIOD 1, at Simulation time=01/01 00:05 - 00:06
  5. ** ~~~ ** PlantLoop name= HOT WATER LOOP
  7. ** ~~~ ** Plant Connector:Mixer name= HOT WATER LOOP DEMAND MIXER
  9. ** ~~~ ** Mixer outlet mass flow rate= 421153668370655. {kg/s}
  11. ** ~~~ ** Plant Connector:Splitter name= HOT WATER LOOP DEMAND SPLITTER
  13. ** ~~~ ** Splitter inlet mass flow rate= 421153668370655. {kg/s}
  15. ** ~~~ ** Difference in two mass flow rates= 6.250000E-002 {kg/s}
  17. ** Severe ** Plant flows do not resolve – splitter inlet flow does not match mixer outlet flow
  19. ** ~~~ ** Environment=RUN PERIOD 1, at Simulation time=01/01 00:05 - 00:06
  21. ** ~~~ ** PlantLoop name= HOT WATER LOOP
  23. ** ~~~ ** Plant Connector:Mixer name= HOT WATER LOOP DEMAND MIXER
  25. ** ~~~ ** Mixer outlet mass flow rate= 421153668370655. {kg/s}
  27. ** ~~~ ** Plant Connector:Splitter name= HOT WATER LOOP DEMAND SPLITTER
  29. ** ~~~ ** Splitter inlet mass flow rate= 421153668370655. {kg/s}
  31. ** ~~~ ** Difference in two mass flow rates= 6.250000E-002 {kg/s}
  33. ** Fatal ** CheckPlantMixerSplitterConsistency: Simulation terminated because of problems in plant flow resolver

Thank you in advance,
Tessa

Here you can find my model:
TEC_Mor_prototype5.gh (1.2 MB)

2

This seems more like an EnergyPlus issue.
Did you try to autosize all flow rates?

3

I don’t exactly know what I changed but the new error i receive is:

  1. ** Severe ** CalcHeatBalanceInsideSurf: The temperature of 3809161.94 C for zone=“BEDROOM1”, for surface=“FLOOR1”
  3. ** ~~~ ** …is very far out of bounds during warmup. This may be an indication of a malformed zone.
  5. ** ~~~ ** During Warmup, Environment=RUN PERIOD 1, at Simulation time=01/01 14:30 - 14:31
  6. ** Fatal ** Program terminates due to preceding condition.
  8. …Summary of Errors that led to program termination:
  10. … Reference severe error count=1
  12. … Last severe error=CalcHeatBalanceInsideSurf: The temperature of 3809161.94 C for zone=“BEDROOM1”, for surface=“FLOOR1”

and

  1. ************* ===== Recurring Error Summary =====
  3. ************* The following recurring error messages occurred.
  7. ************* ** Warning ** Plant loop exceeding upper temperature limit, PlantLoop=“CHILLED WATER LOOP”
  9. ************* ** ~~~ ** This error occurred 78 total times;
  11. ************* ** ~~~ ** during Warmup 78 times;
  13. ************* ** ~~~ ** during Sizing 0 times.
  15. ************* ** ~~~ ** Max=60.

If I unplug this zone it will return the same error for the other zone.

What does it mean with malformed zone?

Please find my most recent model:
TEC_Mor_prototype5.gh (1.3 MB)
And the full error message:
error_message.txt (11.7 KB)

4

@tessar93
As I suggested in the other post, it is better to start from a single box zone first to better isolate problems from each other.

5

I have disabled all the other zones but I am still receiving the same error message for a different surface.

image
image975×217 11.8 KB

Thank you for looking at my issue. Do you have any suggestions why it finds such a high temperature?

TEC_Mor_prototype_singlezone.gh (1.3 MB)
error_message.txt (7.3 KB)

6

@tessar93 I have checked your file, here is a minimum working file, and you can start from here:
TEC_Mor_prototype_singlezone_MP’.gh (780.9 KB)

7

Thank you very much. Looking at the file you made I have been able to fix my model and it is working now.