PlantEquipmentOperation:OutdoorDryBulb does not work with some components

[jmarrec]

Issue overview

CoolingTower:SingleSpeed for eg does not care about the PlantEquipmentOperation.

Incidentally, CoolingTowerDryBulbRangeOp.idf does exhibit the problem. You can just run from 7/15 to 7/16 and see it in action.

The Condenser Loop has two CoolingTower:SingleSpeed BIG TOWER1 & BIG TOWER2, a PlantEquipmentOperation:OutdoorDryBulb that uses both towers until 27°C, and just BIG TOWER1 above (which makes zero sense, but whatever).

  CondenserEquipmentOperationSchemes,
    Tower Loop Operation,    !- Name
    PlantEquipmentOperation:OutdoorDryBulb,  !- Control Scheme 1 Object Type
    Year Round Tower Operation,  !- Control Scheme 1 Name
    PlantOnSched;            !- Control Scheme 1 Schedule Name

  PlantEquipmentOperation:OutdoorDryBulb,
    Year Round Tower Operation,  !- Name
    -50,                     !- Dry-Bulb Temperature Range 1 Lower Limit {C}
    27,                      !- Dry-Bulb Temperature Range 1 Upper Limit {C}
    All Towers,              !- Range 1 Equipment List Name
    27,                      !- Dry-Bulb Temperature Range 2 Lower Limit {C}
    70,                      !- Dry-Bulb Temperature Range 2 Upper Limit {C}
    One Tower;               !- Range 2 Equipment List Name

  CondenserEquipmentList,
    All Towers,              !- Name
    CoolingTower:SingleSpeed,!- Equipment 1 Object Type
    Big Tower1,              !- Equipment 1 Name
    CoolingTower:SingleSpeed,!- Equipment 2 Object Type
    Big Tower2;              !- Equipment 2 Name

  CondenserEquipmentList,
    One Tower,               !- Name
    CoolingTower:SingleSpeed,!- Equipment 1 Object Type
    Big Tower1;              !- Equipment 1 Name

I have changed the testfiles to report the output:variable in Detailed rather Hourly.

As can be seen, even when the OA temp is > 27°C, both tower are on.

Details

Some additional details for this issue (if relevant):

• Platform (Operating system, version): all
• Version of EnergyPlus (if using an intermediate build, include SHA): develop, 18f5c3f
• Reported here on unmethours: https://unmethours.com/question/99620/plantequipmentoperationoutdoordrybulb-does-not-work/

Checklist

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

• Defect file added (list location of defect file here): testfiles/CoolingTowerDryBulbRangeOp.idf
• Ticket added to EnergyPlus Defect Complexity (Github Project)
• Pull request created (the pull request will have additional tasks related to reviewing changes that fix this defect)

[jmarrec]

Seems like the MyLoad is set correctly on the comps of the EquipmentList in PlantCondLoopOperation::ManagePlantLoadDistribution

EnergyPlus/src/EnergyPlus/PlantCondLoopOperation.cc

Lines 222 to 316 in 18f5c3f

	case OpScheme::DryBulbRB: {
	RangeVariable = state.dataEnvrn->OutDryBulbTemp;
	break;
	}
	case OpScheme::WetBulbRB: {
	RangeVariable = state.dataEnvrn->OutWetBulbTemp;
	break;
	}
	case OpScheme::RelHumRB: {
	RangeVariable = state.dataEnvrn->OutRelHum;
	break;
	}
	case OpScheme::DewPointRB: {
	RangeVariable = state.dataEnvrn->OutDewPointTemp;
	break;
	}
	case OpScheme::DryBulbTDB:
	case OpScheme::WetBulbTDB:
	case OpScheme::DewPointTDB: {
	RangeVariable = FindRangeVariable(state, plantLoc.loopNum, CurSchemePtr, CurSchemeType);
	break;
	}
	default: {
	// No controls specified. This is a fatal error
	ShowFatalError(state,
	format("Invalid Operation Scheme Type Requested={}, in ManagePlantLoadDistribution",
	state.dataPlnt->PlantLoop(plantLoc.loopNum).OpScheme(CurSchemePtr).TypeOf));
	}
	}
	switch (CurSchemeType) {
	case OpScheme::Uncontrolled: {
	//!***what else do we do with 'uncontrolled' equipment?
	// There's an equipment list...but I think the idea is to just
	// Set one component to run in an 'uncontrolled' way (whatever that means!)
	break;
	}
	case OpScheme::CompSetPtBased: {
	// check for EMS Control
	TurnOnPlantLoopPipes(state, plantLoc.loopNum, plantLoc.loopSideNum);
	FindCompSPLoad(state, plantLoc, CurCompLevelOpNum);
	break;
	}
	case OpScheme::EMS: {
	TurnOnPlantLoopPipes(state, plantLoc.loopNum, plantLoc.loopSideNum);
	DistributeUserDefinedPlantLoad(state, plantLoc, CurCompLevelOpNum, CurSchemePtr, LoopDemand, RemLoopDemand);
	break;
	}
	default: { // it's a range based control type with multiple equipment lists
	CurListNum = 0;
	for (ListNum = 1; ListNum <= NumEquipLists; ++ListNum) {
	// setpointers to 'PlantLoop()%OpScheme()...'structure
	ListPtr = this_component.OpScheme(CurCompLevelOpNum).EquipList(ListNum).ListPtr;
	RangeHiLimit = this_op_scheme.EquipList(ListPtr).RangeUpperLimit;
	RangeLoLimit = this_op_scheme.EquipList(ListPtr).RangeLowerLimit;
	if (CurSchemeType == OpScheme::HeatingRB || CurSchemeType == OpScheme::CoolingRB) {
	// these limits are stored with absolute values, but the LoopDemand can be negative for cooling
	TestRangeVariable = std::abs(RangeVariable);
	} else {
	TestRangeVariable = RangeVariable;
	}
	// trying to do something where the last stage still runs the equipment but at the hi limit.
	if (TestRangeVariable < RangeLoLimit || TestRangeVariable > RangeHiLimit) {
	if ((TestRangeVariable > RangeHiLimit) && (ListPtr == this_op_scheme.EquipListNumForLastStage)) {
	// let this go thru, later AdjustChangeInLoadForLastStageUpperRangeLimit will cap dispatch to RangeHiLimit
	CurListNum = ListNum;
	break;
	} else {
	continue;
	}
	} else {
	CurListNum = ListNum;
	break;
	}
	}
	if (CurListNum > 0) {
	// there could be equipment on another list that needs to be nulled out, it may have a load from earlier iteration
	for (ListNum = 1; ListNum <= NumEquipLists; ++ListNum) {
	if (ListNum == CurListNum) continue; // leave current one alone
	NumCompsOnList = this_op_scheme.EquipList(ListNum).NumComps;
	for (CompIndex = 1; CompIndex <= NumCompsOnList; ++CompIndex) {
	EquipBranchNum = this_op_scheme.EquipList(ListNum).Comp(CompIndex).BranchNumPtr;
	EquipCompNum = this_op_scheme.EquipList(ListNum).Comp(CompIndex).CompNumPtr;
	loop_side.Branch(EquipBranchNum).Comp(EquipCompNum).MyLoad = 0.0;
	}
	}
	if (this_op_scheme.EquipList(ListPtr).NumComps > 0) {
	TurnOnPlantLoopPipes(state, plantLoc.loopNum, plantLoc.loopSideNum);
	DistributePlantLoad(state, plantLoc.loopNum, plantLoc.loopSideNum, CurSchemePtr, ListPtr, LoopDemand, RemLoopDemand);
	LoadDistributionWasPerformed = true;
	}
	}

But it's ignored. Merkel is the only cooling tower that takes a Load parameter apparently.

EnergyPlus/src/EnergyPlus/CondenserLoopTowers.hh

Lines 390 to 396 in 18f5c3f

	void calculateSingleSpeedTower(EnergyPlusData &state);
	void calculateTwoSpeedTower(EnergyPlusData &state);
	void calculateMerkelVariableSpeedTower(EnergyPlusData &state, Real64 &MyLoad);
	void calculateVariableSpeedTower(EnergyPlusData &state);