Crash in Fluid Cooler Code

[Myoldmopar]

Issue overview

The fluid cooler sizing routine assumes the user has provided a sizing:plant object without checking. This leads to a hard crash in the file linked below.

Checklist

Add to this list or remove from it as applicable. This is a simple templated set of guidelines.

• Defect file is 24.2 example file with a fluid cooler added but missing any plant sizing:
  • SuperMarket_DetailedWaterCondenser_Faulty.idf.txt
• If you turn on plant sizing in simulation control, and add a sizing:plant object, it avoids the crash:
  • SuperMarket_DetailedWaterCondenser_WithPlantSizingAdded.idf.txt

[jmarrec]

EvaporativeFluidCooler has the same issue.

[jmarrec]

Other problems found in FluidCoolers.cc:

DesignLeavingWaterTemp not set in almost all cases

DesignLeavingWaterTemp is ONLY ever assigned when DesignWaterFlowRateWasAutoSized here

EnergyPlus/src/EnergyPlus/FluidCoolers.cc

Line 982 in acda84e

this->DesignLeavingWaterTemp = state.dataSize->PlantSizData(PltSizCondNum).ExitTemp;

Yet it is used to report itself, the approach, and the range to the tabular output here

EnergyPlus/src/EnergyPlus/FluidCoolers.cc

Lines 1637 to 1646 in acda84e

	OutputReportPredefined::PreDefTableEntry(
	state, state.dataOutRptPredefined->pdchCTFCRange, this->Name, this->DesignEnteringWaterTemp - this->DesignLeavingWaterTemp);
	OutputReportPredefined::PreDefTableEntry(
	state, state.dataOutRptPredefined->pdchCTFCApproach, this->Name, this->DesignLeavingWaterTemp - this->DesignEnteringAirWetBulbTemp);
	OutputReportPredefined::PreDefTableEntry(
	state, state.dataOutRptPredefined->pdchCTFCDesFanPwr, this->Name, this->HighSpeedFanPower); // equivalent to Design Fan Power?
	OutputReportPredefined::PreDefTableEntry(
	state, state.dataOutRptPredefined->pdchCTFCDesInletAirWBT, this->Name, this->DesignEnteringAirWetBulbTemp);
	OutputReportPredefined::PreDefTableEntry(state, state.dataOutRptPredefined->pdchCTFCDesWaterFlowRate, this->Name, this->DesignWaterFlowRate);
	OutputReportPredefined::PreDefTableEntry(state, state.dataOutRptPredefined->pdchCTFCLevWaterSPTemp, this->Name, this->DesignLeavingWaterTemp);

Precision for reporting DesignWaterFlowRate

It is defaulted to 2, which is insufficient

EnergyPlus/src/EnergyPlus/FluidCoolers.cc

Line 1645 in acda84e

OutputReportPredefined::PreDefTableEntry(state, state.dataOutRptPredefined->pdchCTFCDesWaterFlowRate, this->Name, this->DesignWaterFlowRate);

---

Example file tabular output

See the testfiles/FluidCooler.idf: energyplus -w $chig_epw -d out FluidCooler.idf

Same in markdown, removing some columns for clarity

	Range [C]	Approach [C]	Design Fan Power [W]	Design Inlet Air Wet-Bulb Temperature [C]	Design Water Flow Rate [m3/s]	Leaving Water Setpoint Temperature [C]
BIG FLUIDCOOLER	51.67	-25.60	615.31	25.60	0.00	0.00