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| Type | Intent | Optional | Attributes | Name | ||
|---|---|---|---|---|---|---|
| integer | :: | ChillNum | ||||
| real(kind=r64) | :: | MyLoad | ||||
| logical, | intent(in) | :: | RunFlag |
Nodes of different colours represent the following:
Solid arrows point from a procedure to one which it calls. Dashed arrows point from an interface to procedures which implement that interface. This could include the module procedures in a generic interface or the implementation in a submodule of an interface in a parent module. Where possible, edges connecting nodes are given different colours to make them easier to distinguish in large graphs.
Nodes of different colours represent the following:
Solid arrows point from a procedure to one which it calls. Dashed arrows point from an interface to procedures which implement that interface. This could include the module procedures in a generic interface or the implementation in a submodule of an interface in a parent module. Where possible, edges connecting nodes are given different colours to make them easier to distinguish in large graphs.
SUBROUTINE CalcExhaustAbsorberHeaterModel(ChillNum,MyLoad,Runflag)
! SUBROUTINE INFORMATION:
! AUTHOR Jason Glazer and Michael J. Witte
! DATE WRITTEN March 2001
! MODIFIED Mahabir Bhandari, ORNL, Aug 2011, modified to accomodate exhaust fired double effect absorption chiller
! RE-ENGINEERED na
! PURPOSE OF THIS SUBROUTINE:
! Simulate a Exhaust fired (Exhaust consuming) absorption chiller using
! curves and inputs similar to DOE-2.1e
! METHODOLOGY EMPLOYED:
! Curve fit of performance data
! REFERENCES:
! 1. DOE-2.1e Supplement and source code
! 2. CoolTools GasMod work
! USE STATEMENTS:
USE DataGlobals, ONLY : BeginFullSimFlag
USE DataEnvironment, ONLY : OutDryBulbTemp
USE DataHVACGlobals, ONLY : FirstTimeStepSysFlag, TimeStepSys
USE CurveManager, ONLY : CurveValue
USE DataPlant, ONLY : PlantLoop, SingleSetpoint, DualSetpointDeadband
USE DataBranchAirLoopPlant, ONLY: MassFlowTolerance
USE FluidProperties, ONLY : GetSpecificHeatGlycol, GetDensityGlycol
USE PlantUtilities, ONLY : SetComponentFlowRate
USE Psychrometrics, ONLY:PsyCpAirFnWTdb
USE MicroturbineElectricGenerator, ONLY: SimMTGenerator
IMPLICIT NONE
! SUBROUTINE ARGUMENT DEFINITIONS:
INTEGER :: ChillNum ! Absorber number
REAL(r64) :: MyLoad ! operating load
LOGICAL, INTENT(IN) :: RunFlag ! TRUE when Absorber operating
! FlowLock = 0 if mass flow rates may be changed by loop components
! FlowLock = 1 if mass flow rates may not be changed by loop components
! FlowLock = 2 if overloaded and mass flow rates has changed to a small amount and Tout drops
! below Setpoint
! SUBROUTINE PARAMETER DEFINITIONS:
REAL(r64), parameter :: WaterMassFlowTol=0.001d0 ! kg/s - minimum significan mass flow rate
REAL(r64), parameter :: AbsLeavingTemp = 176.667d0 ! C - Minimum temperature leaving the Chiller absorber (350 F)
!INTEGER :: ExhTempLTAbsLeavingTempCount = 0 ! Counter for exhaust temp < absorber leaving air temp warning messages
! INTERFACE BLOCK SPECIFICATIONS
! na
! DERIVED TYPE DEFINITIONS
! na
! SUBROUTINE LOCAL VARIABLE DECLARATIONS:
! Local copies of ExhaustAbsorberSpecs Type
! all variables that are local copies of data structure
! variables are prefaced with an "l" for local.
REAL(r64) :: lNomCoolingCap ! W - design nominal capacity of Absorber
REAL(r64) :: lNomHeatCoolRatio ! ratio of heating to cooling capacity
REAL(r64) :: lThermalEnergyHeatRatio ! ratio of ThermalEnergy input to heating output
REAL(r64) :: lElecHeatRatio ! ratio of electricity input to heating output
INTEGER :: lHeatReturnNodeNum ! absorber hot water inlet node number, water side
INTEGER :: lHeatSupplyNodeNum ! absorber hot water outlet node number, water side
REAL(r64) :: lMinPartLoadRat ! min allowed operating frac full load
REAL(r64) :: lMaxPartLoadRat ! max allowed operating frac full load
REAL(r64) :: lOptPartLoadRat ! optimal operating frac full load
INTEGER :: lHeatCapFCoolCurve ! Heating Capacity Function of Cooling Capacity Curve
INTEGER :: lThermalEnergyHeatFHPLRCurve ! ThermalEnergy Input to heat output ratio during heating only function
! Local copies of ExhaustAbsorberReportVars Type
REAL(r64) :: lHeatingLoad ! heating load on the chiller
REAL(r64) :: lHeatingEnergy ! heating energy
REAL(r64) :: lThermalEnergyUseRate ! instantaneous use of Thermal Energy for period
REAL(r64) :: lThermalEnergy ! variable to track total Thermal Energy used for a period (reference only)
REAL(r64) :: lCoolThermalEnergyUseRate ! instantaneous use of thermal energy for period for cooling
REAL(r64) :: lHeatThermalEnergyUseRate ! instantaneous use of thermal energy for period for heating
REAL(r64) :: lHeatThermalEnergy ! variable to track total ThermalEnergy used for a period for heating
REAL(r64) :: lElectricPower ! parasitic electric power used (was PumpingPower)
REAL(r64) :: lElectricEnergy ! track the total electricity used for a period (was PumpingEnergy)
REAL(r64) :: lCoolElectricPower ! parasitic electric power used for cooling
REAL(r64) :: lHeatElectricPower ! parasitic electric power used for heating
REAL(r64) :: lHeatElectricEnergy ! track the total electricity used for a period for heating
REAL(r64) :: lHotWaterReturnTemp ! reporting: hot water return (inlet) temperature
REAL(r64) :: lHotWaterSupplyTemp ! reporting: hot water supply (outlet) temperature
REAL(r64) :: lHotWaterMassFlowRate ! reporting: hot water mass flow rate
REAL(r64) :: lCoolPartLoadRatio ! operating part load ratio (load/capacity for cooling)
REAL(r64) :: lHeatPartLoadRatio ! operating part load ratio (load/capacity for heating)
REAL(r64) :: lAvailableHeatingCapacity ! current heating capacity
REAL(r64) :: lFractionOfPeriodRunning
Real(r64) :: lHotWaterMassFlowRateMax ! Maximum flow rate through the evaporator
Real(r64) :: lExhaustInTemp ! Exhaust inlet temperature
Real(r64) :: lExhaustInFlow ! Exhaust inlet flow rate
Real(r64) :: lExhHeatRecPotentialHeat ! Exhaust heat recovery potential
Real(r64) :: lExhaustAirHumRat
! other local variables
REAL(r64) :: HeatDeltaTemp ! hot water temperature difference
REAL(r64) :: HeatSupplySetPointTemp
INTEGER :: LoopNum
INTEGER :: LoopSideNum
REAL(r64) :: Cp_HW ! local fluid specific heat for hot water
INTEGER :: GeneratorType
INTEGER :: GenIndex1
REAL(r64) ::CpAir
REAL(r64) :: rhoHW ! local fluid density for hot water
INTEGER :: lExhaustAirInletNodeNum ! Combustion Air Inlet Node number
CHARACTER(len=MaxNameLength) :: GeneratorName
! INTEGER :: lExhaustAirOutletNodeNum ! Combustion Air Outlet (Exhaust) Node number
!initialize all output variables to zero
lHeatingLoad = 0.0d0
lHeatingEnergy = 0.0d0
lThermalEnergyUseRate = 0.0d0
lThermalEnergy = 0.0d0
lCoolThermalEnergyUseRate = 0.0d0
lHeatThermalEnergyUseRate = 0.0d0
lHeatThermalEnergy = 0.0d0
lElectricPower = 0.0d0
lElectricEnergy = 0.0d0
lCoolElectricPower = 0.0d0
lHeatElectricPower = 0.0d0
lHeatElectricEnergy = 0.0d0
lHotWaterReturnTemp = 0.0d0
lHotWaterSupplyTemp = 0.0d0
lHotWaterMassFlowRate = 0.0d0
lCoolPartLoadRatio = 0.0d0
lHeatPartLoadRatio = 0.0d0
lAvailableHeatingCapacity = 0.0d0
lFractionOfPeriodRunning = 0.0d0
lExhaustInTemp = 0.0d0
lExhaustInFlow = 0.0d0
lExhHeatRecPotentialHeat = 0.0d0
lExhaustAirHumRat =0.0d0
! set node values to data structure values for nodes
lHeatReturnNodeNum = ExhaustAbsorber(ChillNum)%HeatReturnNodeNum
lHeatSupplyNodeNum = ExhaustAbsorber(ChillNum)%HeatSupplyNodeNum
lExhaustAirInletNodeNum = ExhaustAbsorber(ChillNum)%ExhaustAirInletNodeNum
! set local copies of data from rest of input structure
lNomCoolingCap = ExhaustAbsorber(ChillNum)%NomCoolingCap
lNomHeatCoolRatio = ExhaustAbsorber(ChillNum)%NomHeatCoolRatio
lThermalEnergyHeatRatio = ExhaustAbsorber(ChillNum)%ThermalEnergyHeatRatio
lElecHeatRatio = ExhaustAbsorber(ChillNum)%ElecHeatRatio
lMinPartLoadRat = ExhaustAbsorber(ChillNum)%MinPartLoadRat
lMaxPartLoadRat = ExhaustAbsorber(ChillNum)%MaxPartLoadRat
lOptPartLoadRat = ExhaustAbsorber(ChillNum)%OptPartLoadRat
lHeatCapFCoolCurve = ExhaustAbsorber(ChillNum)%HeatCapFCoolCurve
lThermalEnergyHeatFHPLRCurve = ExhaustAbsorber(ChillNum)%ThermalEnergyHeatFHPLRCurve
lHotWaterMassFlowRateMax = Exhaustabsorber(chillnum)%DesHeatMassFlowRate
LoopNum = ExhaustAbsorber(ChillNum)%HWLoopNum
LoopSideNum = ExhaustAbsorber(ChillNum)%HWLoopSideNum
Cp_HW = GetSpecificHeatGlycol(PlantLoop(LoopNum)%FluidName, &
lHotWaterReturnTemp, &
PlantLoop(LoopNum)%FluidIndex, &
'CalcExhaustAbsorberHeaterModel')
rhoHW = GetDensityGlycol(PlantLoop(LoopNum)%FluidName, &
lHotWaterReturnTemp, &
PlantLoop(LoopNum)%FluidIndex, &
'CalcExhaustAbsorberHeaterModel')
lCoolElectricPower = ExhaustAbsorberReport(ChillNum)%CoolElectricPower
lCoolThermalEnergyUseRate = ExhaustAbsorberReport(ChillNum)%CoolThermalEnergyUseRate
lCoolPartLoadRatio = ExhaustAbsorberReport(ChillNum)%CoolPartLoadRatio
! initialize entering conditions
lHotWaterReturnTemp = Node(lHeatReturnNodeNum)%Temp
lHotWaterMassFlowRate = Node(lHeatReturnNodeNum)%MassFlowRate
SELECT CASE (PlantLoop(LoopNum)%LoopDemandCalcScheme)
CASE (SingleSetpoint)
HeatSupplySetPointTemp = Node(lHeatSupplyNodeNum)%TempSetPoint
CASE (DualSetpointDeadband)
HeatSupplySetPointTemp = Node(lHeatSupplyNodeNum)%TempSetPointLo
END SELECT
HeatDeltaTemp = ABS(lHotWaterReturnTemp - HeatSupplySetPointTemp)
!If no loop demand or Absorber OFF, return
! will need to modify when absorber can act as a boiler
IF (MyLoad<=0 .OR. .NOT. Runflag) THEN
!set node temperatures
lHotWaterSupplyTemp = lHotWaterReturnTemp
HeatDeltaTemp = 0.0d0
lFractionOfPeriodRunning = MIN(1.0d0,MAX(lHeatPartLoadRatio,lCoolPartLoadRatio)/lMinPartLoadRat)
ELSE
!Determine available heating capacity using the current cooling load
lAvailableHeatingCapacity = ExhaustAbsorber(ChillNum)%NomHeatCoolRatio * &
ExhaustAbsorber(ChillNum)%NomCoolingCap * CurveValue(lHeatCapFCoolCurve, &
(ExhaustAbsorberReport(ChillNum)%CoolingLoad / ExhaustAbsorber(ChillNum)%NomCoolingCap))
!Calculate current load for heating
MyLoad = SIGN(MAX(ABS(MyLoad), ExhaustAbsorberReport(ChillNum)%HeatingCapacity * lMinPartLoadRat), MyLoad)
MyLoad = SIGN(MIN(ABS(MyLoad), ExhaustAbsorberReport(ChillNum)%HeatingCapacity * lMaxPartLoadRat), MyLoad)
! Determine the following variables depending on if the flow has been set in
! the nodes (flowlock=1 to 2) or if the amount of load is still be determined (flowlock=0)
! chilled water flow,
! cooling load taken by the chiller, and
! supply temperature
SELECT CASE (PlantLoop(LoopNum)%Loopside(LoopSideNum)%FlowLock)
CASE (0) ! mass flow rates may be changed by loop components
lHeatingLoad = ABS(MyLoad)
IF (HeatDeltaTemp /= 0) THEN
lHotWaterMassFlowRate = ABS(lHeatingLoad / (Cp_HW * HeatDeltaTemp))
CALL SetComponentFlowRate(lHotWaterMassFlowRate, &
ExhaustAbsorber(ChillNum)%HeatReturnNodeNum, &
ExhaustAbsorber(ChillNum)%HeatSupplyNodeNum, &
ExhaustAbsorber(ChillNum)%HWLoopNum, &
ExhaustAbsorber(ChillNum)%HWLoopSideNum, &
ExhaustAbsorber(ChillNum)%HWBranchNum, &
ExhaustAbsorber(ChillNum)%HWCompNum)
ELSE
lHotWaterMassFlowRate = 0.0d0
CALL ShowRecurringWarningErrorAtEnd('ExhaustAbsorberChillerModel:Heating"'//TRIM(ExhaustAbsorber(ChillNum)%Name)// &
'", DeltaTemp = 0 in mass flow calculation',ExhaustAbsorber(ChillNum)%DeltaTempHeatErrCount)
END IF
lHotWaterSupplyTemp = HeatSupplySetPointTemp
CASE (1) ! mass flow rates may not be changed by loop components
lHotWaterSupplyTemp = HeatSupplySetPointTemp
lHeatingLoad = ABS(lHotWaterMassFlowRate * Cp_HW * HeatDeltaTemp)
!DSU this "2" is not a real state for flowLock
CASE (2) ! chiller is underloaded and mass flow rates has changed to a small amount and Tout drops below Setpoint
! MJW 07MAR01 Borrow logic from steam absorption module
! The following conditional statements are made to avoid extremely small EvapMdot
! & unreasonable EvapOutletTemp due to overloading.
! Avoid 'divide by zero' due to small EvapMdot
IF(lHotWaterMassFlowRate < MassFlowTolerance) THEN
HeatDeltaTemp = 0.0d0
ELSE
HeatDeltaTemp = ABS(MyLoad) / (Cp_HW * lHotWaterMassFlowRate)
END IF
lHotWaterSupplyTemp = lHotWaterReturnTemp + HeatDeltaTemp
lHeatingLoad = ABS(lHotWaterMassFlowRate * Cp_HW * HeatDeltaTemp)
END SELECT
!Calculate operating part load ratio for cooling
lHeatPartLoadRatio = lHeatingLoad / lAvailableHeatingCapacity
!Calculate ThermalEnergy consumption for heating
! ThermalEnergy used for heating availCap * HIR * HIR-FT * HIR-FPLR
lHeatThermalEnergyUseRate = lAvailableHeatingCapacity * lThermalEnergyHeatRatio &
* CurveValue(lThermalEnergyHeatFHPLRCurve,lHeatPartLoadRatio)
! calculate the fraction of the time period that the chiller would be running
! use maximum from heating and cooling sides
lFractionOfPeriodRunning = MIN(1.0d0,MAX(lHeatPartLoadRatio,lCoolPartLoadRatio)/lMinPartLoadRat)
!Calculate electric parasitics used
! for heating based on nominal capacity not available capacity
lHeatElectricPower = lNomCoolingCap * lNomHeatCoolRatio * lElecHeatRatio * lFractionOfPeriodRunning
! Coodinate electric parasitics for heating and cooling to avoid double counting
! Total electric is the max of heating electric or cooling electric
! If heating electric is greater, leave cooling electric and subtract if off of heating elec
! If cooling electric is greater, set heating electric to zero
lExhaustInTemp = Node(lExhaustAirInletNodeNum)%Temp
lExhaustInFlow = Node(lExhaustAirInletNodeNum)%MassFlowRate
CpAir = PsyCpAirFnWTdb(lExhaustAirHumRat,lExhaustInTemp)
lExhHeatRecPotentialHeat = lExhaustInFlow * Cpair * ( lExhaustInTemp - AbsLeavingTemp )
IF (lExhHeatRecPotentialHeat .LT. lHeatThermalEnergyUseRate ) THEN
IF(ExhaustAbsorber(ChillNum)%ExhTempLTAbsLeavingHeatingTempIndex == 0)THEN
CALL ShowWarningError('ChillerHeater:Absorption:DoubleEffect "'//TRIM(ExhaustAbsorber(ChillNum)%Name)//'"')
CALL ShowContinueError('...Exhaust temperature and flow input from Micro Turbine is not sufficient '&
//'to run the chiller during heating .')
CALL ShowContinueError('...Value of Exhaust air inlet temp ='//TRIM(TrimSigDigits(lExhaustInTemp,4))//' C.')
CALL ShowContinueError('... and Exhaust air flow rate of '//TRIM(TrimSigDigits(lExhaustInFlow,2))//' kg/s.')
CALL ShowContinueError('...Value of minimum absorber leaving temp ='//TRIM(TrimSigDigits(AbsLeavingTemp,4))//' C.')
CALL ShowContinueError('...Either increase the Exhaust temperature (min required = 350 C ) '&
//'or flow or both of Micro Turbine to meet the min available potential criteria.')
CALL ShowContinueErrorTimeStamp('... Simulation will continue.')
ENDIF
CALL ShowRecurringWarningErrorAtEnd('ChillerHeater:Absorption:DoubleEffect "'// &
TRIM(ExhaustAbsorber(ChillNum)%Name)//'":'// &
' Exhaust temperature from Micro Turbine is not sufficient to run the chiller during '// &
'heating warning continues...', &
ExhaustAbsorber(ChillNum)%ExhTempLTAbsLeavingHeatingTempIndex, lExhaustInTemp, AbsLeavingTemp)
! If exhaust is not available, it means the avilable thermal energy is 0.0 and Chiller is not available
lHeatThermalEnergyUseRate = 0.0d0
lHeatElectricPower =0.0d0
lHotWaterSupplyTemp = lHotWaterReturnTemp
HeatDeltaTemp = 0.0d0
lFractionOfPeriodRunning = MIN(1.0d0,MAX(lHeatPartLoadRatio,lCoolPartLoadRatio)/lMinPartLoadRat)
END IF
IF (lHeatElectricPower .LE. lCoolElectricPower) THEN
lHeatElectricPower = 0.0d0
ELSE
lHeatElectricPower = lHeatElectricPower - lCoolElectricPower
ENDIF
ENDIF ! IF(MyLoad==0 .OR. .NOT. Runflag)
! Write into the Report Variables except for nodes
ExhaustAbsorberReport(ChillNum)%HeatingLoad = lHeatingLoad
ExhaustAbsorberReport(ChillNum)%HeatThermalEnergyUseRate = lHeatThermalEnergyUseRate
ExhaustAbsorberReport(ChillNum)%HeatElectricPower = lHeatElectricPower
ExhaustAbsorberReport(ChillNum)%HotWaterReturnTemp = lHotWaterReturnTemp
ExhaustAbsorberReport(ChillNum)%HotWaterSupplyTemp = lHotWaterSupplyTemp
ExhaustAbsorberReport(ChillNum)%HotWaterFlowRate = lHotWaterMassFlowRate
ExhaustAbsorberReport(ChillNum)%HeatPartLoadRatio = lHeatPartLoadRatio
ExhaustAbsorberReport(ChillNum)%HeatingCapacity = lAvailableHeatingCapacity
ExhaustAbsorberReport(ChillNum)%FractionOfPeriodRunning = lFractionOfPeriodRunning
! write the combined heating and cooling ThermalEnergy used and electric used
ExhaustAbsorberReport(ChillNum)%ThermalEnergyUseRate = lCoolThermalEnergyUseRate + lHeatThermalEnergyUseRate
ExhaustAbsorberReport(ChillNum)%ElectricPower = lCoolElectricPower + lHeatElectricPower
ExhaustAbsorberReport(ChillNum)%ExhaustInTemp = lExhaustInTemp
ExhaustAbsorberReport(ChillNum)%ExhaustInFlow = lExhaustInFlow
ExhaustAbsorberReport(ChillNum)%ExhHeatRecPotentialHeat = lExhHeatRecPotentialHeat
END SUBROUTINE CalcExhaustAbsorberHeaterModel