Buildings.Fluid.Chillers.ModularReversible
Package for reversible and non-reversible chillers using a modular model approach
Information
Package with models and packages for the modular reversible chiller approach. See the Buildings.Fluid.HeatPumps.ModularReversible.UsersGuide for more information.Extends from Modelica.Icons.VariantsPackage (Icon for package containing variants).
Package Content
| Name | Description |
|---|---|
 UsersGuide
|
User's Guide for modular reversible heat pump and chiller models |
 CarnotWithLosses
|
Reversible chiller using Carnot approach with losses (frost, heat, inertia) |
| LargeScaleWaterToWater
|
Large scale water to water chiller |
| Modular
|
Grey-box model for reversible and non-reversible chillers |
 Controls
|
Package of control sequences |
 RefrigerantCycle
|
Package for chiller refrigerant cycle modules |
| Data
|
Package for data records |
 Examples
|
Collection of models that illustrate model use and test models |
| Validation
|
Package for model validation |
 BaseClasses
|
Package with base classes for Buildings.Fluid.Chillers.ModularReversible |
Buildings.Fluid.Chillers.ModularReversible.CarnotWithLosses
Reversible chiller using Carnot approach with losses (frost, heat, inertia)
Information
Model of a reversible chiller.
This model extends Buildings.Fluid.Chillers.ModularReversible.Modular and selects the constant Carnot effectiveness module for chillers ( Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.ConstantCarnotEffectiveness) and heat pumps ( Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.ConstantCarnotEffectiveness) to model a reversible chiller. For the heating operation, the nominal approach temperatures are used as a constant to avoid nonlinear system of equations.
Furthermore, losses are enabled to model the chiller with a more realistic behaviour:
- Heat losses to the ambient (can be disabled)
- Refrigerant inertia using a first order delay
- Evaporator frosting assuming an air-sink chiller
For more information, see Buildings.Fluid.HeatPumps.ModularReversible.UsersGuide.
Extends from Buildings.Fluid.Chillers.ModularReversible.Modular (Grey-box model for reversible and non-reversible chillers).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package MediumCon | PartialMedium | Medium on condenser side | |
| replaceable package MediumEva | PartialMedium | Medium on evaporator side | |
| Boolean | use_rev | false | =true if the chiller or heat pump is reversible |
| replaceable model RefrigerantCycleChillerCooling | Buildings.Fluid.Chillers.Mod... | Refrigerant cycle module for the cooling mode | |
| replaceable model RefrigerantCycleChillerHeating | Buildings.Fluid.HeatPumps.Mo... | Refrigerant cycle module for the heating mode | |
| Real | etaCarnot_nominal | 0.3 | Constant Carnot effectiveness |
| Nominal condition | |||
| HeatFlowRate | QCoo_flow_nominal | Nominal cooling capcaity [W] | |
| Temperature | TEvaCoo_nominal | Nominal temperature of the cooled fluid [K] | |
| Temperature | TConCoo_nominal | Nominal temperature of the heated fluid [K] | |
| TemperatureDifference | TAppCon_nominal | if cpCon < 1500 then 5 else 2 | Temperature difference between refrigerant and working fluid outlet in condenser [K] |
| TemperatureDifference | TAppEva_nominal | if cpEva < 1500 then 5 else 2 | Temperature difference between refrigerant and working fluid outlet in evaporator [K] |
| Inertia | |||
| replaceable model RefrigerantCycleInertia | NoInertia | Inertia between the refrigerant cycle outputs and the heat exchangers. | |
| Safety control | |||
| Boolean | use_intSafCtr | true | =true to enable internal safety control |
| Wuellhorst2021 | safCtrPar | redeclare parameter Building... | Safety control parameters |
| Nominal condition - Pressure losses | |||
| TemperatureDifference | dTCon_nominal | Nominal temperature difference in condenser medium, used to calculate mass flow rate [K] | |
| MassFlowRate | mCon_flow_nominal | (PEle_nominal - QCoo_flow_no... | Nominal mass flow rate of the condenser medium [kg/s] |
| PressureDifference | dpCon_nominal | Pressure drop at nominal mass flow rate [Pa] | |
| TemperatureDifference | dTEva_nominal | Nominal temperature difference in evaporator medium, used to calculate mass flow rate [K] | |
| MassFlowRate | mEva_flow_nominal | -QCoo_flow_nominal/(dTEva_no... | Nominal mass flow rate of the evaporator medium [kg/s] |
| PressureDifference | dpEva_nominal | Pressure drop at nominal mass flow rate [Pa] | |
| Nominal condition - Heating | |||
| HeatFlowRate | QHea_flow_nominal | PEle_nominal*refCyc.refCycCh... | Nominal heating capacity [W] |
| Temperature | TEvaHea_nominal | Nominal temperature of the heated fluid [K] | |
| Temperature | TConHea_nominal | Nominal temperature of the cooled fluid [K] | |
| Refrigerant cycle inertia | |||
| Time | refIneTimCon | 300 | Refrigerant cycle inertia time constant for first order delay [s] |
| Integer | nthOrd | 1 | Order of refrigerant cycle interia |
| Assumptions | |||
| Evaporator | |||
| Boolean | allowFlowReversalEva | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Condenser | |||
| Boolean | allowFlowReversalCon | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Advanced | |||
| Boolean | allowDifferentDeviceIdentifiers | false | if use_rev=true, device data for cooling and heating need to entered. Set allowDifferentDeviceIdentifiers=true to allow different device identifiers devIde |
| Boolean | calEff | true | =false to disable efficiency calculation, may speed up the simulation |
| Real | limWarSca | 0.05 | Allowed difference in scaling '|scaFacHea - scaFacCoo| / scaFacHea', if exceeded, a warning will be issued [1] |
| Diagnostics | |||
| Boolean | show_T | false | = true, if actual temperature at port is computed |
| Real | ySet_small | 0.01 | Threshold for relative speed for the device to be considered on |
| Flow resistance | |||
| Boolean | from_dp | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
| Boolean | linearized | false | = true, use linear relation between m_flow and dp for any flow rate |
| Condenser | |||
| Dynamics | |||
| Time | tauCon | 30 | Condenser heat transfer time constant at nominal flow [s] |
| Flow resistance | |||
| Real | deltaMCon | 0.1 | Fraction of nominal mass flow rate where transition to turbulent occurs |
| Heat Losses | |||
| Boolean | use_conCap | true | =true if using capacitor model for condenser heat loss estimation |
| HeatCapacity | CCon | 0 | Heat capacity of the condenser [J/K] |
| ThermalConductance | GConOut | 0 | Outer thermal conductance for condenser heat loss calculations [W/K] |
| ThermalConductance | GConIns | 0 | Inner thermal conductance for condenser heat loss calculations [W/K] |
| Evaporator | |||
| Dynamics | |||
| Time | tauEva | 30 | Evaporator heat transfer time constant at nominal flow [s] |
| Flow resistance | |||
| Real | deltaMEva | 0.1 | Fraction of nominal mass flow rate where transition to turbulent occurs |
| Heat Losses | |||
| Boolean | use_evaCap | true | =true if using capacitor model for evaporator heat loss estimation |
| HeatCapacity | CEva | 0 | Heat capacity of the evaporator [J/K] |
| ThermalConductance | GEvaOut | 0 | Outer thermal conductance for evaporator heat loss calculations [W/K] |
| ThermalConductance | GEvaIns | 0 | Inner thermal conductance for evaporator heat loss calculations [W/K] |
| Initialization | |||
| Parameters | |||
| Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization for refrigerant cycle dynamics (InitialState and InitialOutput are identical) |
| Condenser | |||
| AbsolutePressure | pCon_start | MediumCon.p_default | Start value of pressure [Pa] |
| Temperature | TCon_start | MediumCon.T_default | Start value of temperature [K] |
| Temperature | TConCap_start | MediumCon.T_default | Initial temperature of heat capacity of condenser [K] |
| MassFraction | XCon_start[MediumCon.nX] | MediumCon.X_default | Start value of mass fractions m_i/m [kg/kg] |
| Evaporator | |||
| AbsolutePressure | pEva_start | MediumEva.p_default | Start value of pressure [Pa] |
| Temperature | TEva_start | MediumEva.T_default | Start value of temperature [K] |
| Temperature | TEvaCap_start | MediumEva.T_default | Initial temperature of heat capacity at evaporator [K] |
| MassFraction | XEva_start[MediumEva.nX] | MediumEva.X_default | Start value of mass fractions m_i/m [kg/kg] |
| Dynamics | |||
| Equation | |||
| Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state (only affects fluid-models) |
Connectors
| Type | Name | Description |
|---|---|---|
| FluidPort_a | port_a1 | Fluid connector a1 (positive design flow direction is from port_a1 to port_b1) |
| FluidPort_b | port_b1 | Fluid connector b1 (positive design flow direction is from port_a1 to port_b1) |
| FluidPort_a | port_a2 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) |
| FluidPort_b | port_b2 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) |
| input RealInput | ySet | Relative compressor speed between 0 and 1 |
| input RealInput | TEvaAmb | Ambient temperature on the evaporator side [K] |
| input RealInput | TConAmb | Ambient temperature on the condenser side [K] |
| output RealOutput | QCon_flow | Actual heating heat flow rate added to fluid 1 [W] |
| output RealOutput | P | Electric power consumed by compressor [W] |
| output RealOutput | QEva_flow | Actual cooling heat flow rate removed from fluid 2 [W] |
| output RealOutput | EER | Energy efficieny ratio [1] |
| output RealOutput | COP | Coefficient of performance [1] |
| replaceable model RefrigerantCycleChillerCooling | Refrigerant cycle module for the cooling mode | |
| replaceable model RefrigerantCycleChillerHeating | Refrigerant cycle module for the heating mode | |
| input BooleanInput | coo | =true for cooling, =false for heating |
| Inertia | ||
| replaceable model RefrigerantCycleInertia | Inertia between the refrigerant cycle outputs and the heat exchangers. | |
Modelica definition
model CarnotWithLosses
"Reversible chiller using Carnot approach with losses (frost, heat, inertia)"
extends Buildings.Fluid.Chillers.ModularReversible.Modular(
QHea_flow_nominal=PEle_nominal*refCyc.refCycChiHea.COP_nominal,
redeclare model RefrigerantCycleChillerHeating =
Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.ConstantCarnotEffectiveness
(
PEle_nominal=PEle_nominal,
redeclare Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.Frosting.NoFrosting
iceFacCal,
etaCarnot_nominal=etaCarnot_nominal,
use_constAppTem=true,
TAppCon_nominal=TAppCon_nominal,
TAppEva_nominal=TAppEva_nominal),
redeclare model RefrigerantCycleChillerCooling =
Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.ConstantCarnotEffectiveness
(
redeclare Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.Frosting.FunctionalIcingFactor
iceFacCal(redeclare function icingFactor =
Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.Frosting.Functions.wetterAfjei1997),
TAppCon_nominal=TAppCon_nominal,
TAppEva_nominal=TAppEva_nominal,
etaCarnot_nominal=etaCarnot_nominal),
final allowDifferentDeviceIdentifiers=false,
redeclare model RefrigerantCycleInertia =
Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.Inertias.VariableOrder
(
final refIneFreConst=1/refIneTimCon,
final nthOrd=1,
initType=Modelica.Blocks.Types.Init.InitialOutput));
parameter Real etaCarnot_nominal=0.3 "Constant Carnot effectiveness";
parameter Modelica.Units.SI.TemperatureDifference TAppCon_nominal=if
cpCon < 1500 then 5 else 2
"Temperature difference between refrigerant and working fluid outlet in condenser";
parameter Modelica.Units.SI.TemperatureDifference TAppEva_nominal=if
cpEva < 1500 then 5 else 2
"Temperature difference between refrigerant and working fluid outlet in evaporator";
parameter Modelica.Units.SI.Time refIneTimCon = 300
"Refrigerant cycle inertia time constant for first order delay";
parameter Integer nthOrd=1 "Order of refrigerant cycle interia";
end CarnotWithLosses;
Buildings.Fluid.Chillers.ModularReversible.LargeScaleWaterToWater
Large scale water to water chiller
Information
Large scale water-to-water chiller, using the Buildings.Fluid.Chillers.ModularReversible.Modular approach.
Contrary to the standard sizing approach for the Buildings.Fluid.Chillers.ModularReversible.Modular models, the parameters are based on an automatic estimation as described in Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.LargeScaleWaterToWaterDeclarations.
For more information on the approach, see UsersGuide.
The documentation of the model for cooling is at Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.TableData2D.
Assumptions
- As heat losses are implicitly included in measured data in manufacturer dataseheets, heat losses are disabled.
- Pressure losses are not provided in datasheets. As typical values are unknown, the pressure loss is set to 0 to enable easier usage. However, the parameter is not final and should be replaced if pump electrical power consumption is of interest for your simulation aim.
Extends from Modular (Grey-box model for reversible and non-reversible chillers), Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.LargeScaleWaterToWaterDeclarations (Model with parameters for large scale water-to-water heat pump).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package MediumCon | PartialMedium | Medium on condenser side | |
| replaceable package MediumEva | PartialMedium | Medium on evaporator side | |
| Boolean | use_rev | false | =true if the chiller or heat pump is reversible |
| replaceable model RefrigerantCycleChillerCooling | Buildings.Fluid.Chillers.Mod... | Refrigerant cycle module for the cooling mode | |
| replaceable model RefrigerantCycleChillerHeating | Buildings.Fluid.HeatPumps.Mo... | Refrigerant cycle module for the heating mode | |
| Generic | datTab | redeclare parameter Building... | Data Table of Chiller |
| Nominal condition | |||
| HeatFlowRate | QCoo_flow_nominal | Nominal cooling capcaity [W] | |
| Temperature | TEvaCoo_nominal | Nominal temperature of the cooled fluid [K] | |
| Temperature | TConCoo_nominal | Nominal temperature of the heated fluid [K] | |
| Inertia | |||
| replaceable model RefrigerantCycleInertia | NoInertia | Inertia between the refrigerant cycle outputs and the heat exchangers. | |
| Safety control | |||
| Boolean | use_intSafCtr | true | =true to enable internal safety control |
| Nominal condition - Pressure losses | |||
| TemperatureDifference | dTCon_nominal | (PEle_nominal - QCoo_flow_no... | Nominal temperature difference in condenser medium, used to calculate mass flow rate [K] |
| MassFlowRate | mCon_flow_nominal | autCalMasCon_flow | Nominal mass flow rate of the condenser medium [kg/s] |
| PressureDifference | dpCon_nominal | datTab.dpCon_nominal*scaFac^2 | Pressure drop at nominal mass flow rate [Pa] |
| TemperatureDifference | dTEva_nominal | -QCoo_flow_nominal/cpEva/mEv... | Nominal temperature difference in evaporator medium, used to calculate mass flow rate [K] |
| MassFlowRate | mEva_flow_nominal | autCalMasEva_flow | Nominal mass flow rate of the evaporator medium [kg/s] |
| PressureDifference | dpEva_nominal | datTab.dpEva_nominal*scaFac^2 | Pressure drop at nominal mass flow rate [Pa] |
| Nominal condition - Heating | |||
| HeatFlowRate | QHea_flow_nominal | 0 | Nominal heating capacity [W] |
| Temperature | TEvaHea_nominal | 0 | Nominal temperature of the heated fluid [K] |
| Temperature | TConHea_nominal | 0 | Nominal temperature of the cooled fluid [K] |
| Assumptions | |||
| Evaporator | |||
| Boolean | allowFlowReversalEva | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Condenser | |||
| Boolean | allowFlowReversalCon | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Advanced | |||
| Boolean | allowDifferentDeviceIdentifiers | false | if use_rev=true, device data for cooling and heating need to entered. Set allowDifferentDeviceIdentifiers=true to allow different device identifiers devIde |
| Boolean | calEff | true | =false to disable efficiency calculation, may speed up the simulation |
| Real | limWarSca | 0.05 | Allowed difference in scaling '|scaFacHea - scaFacCoo| / scaFacHea', if exceeded, a warning will be issued [1] |
| Diagnostics | |||
| Boolean | show_T | false | = true, if actual temperature at port is computed |
| Real | ySet_small | 0.01 | Threshold for relative speed for the device to be considered on |
| Flow resistance | |||
| Boolean | from_dp | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
| Boolean | linearized | false | = true, use linear relation between m_flow and dp for any flow rate |
| Condenser | |||
| Dynamics | |||
| Time | tauCon | autCalVCon*rhoCon/autCalMasC... | Condenser heat transfer time constant at nominal flow [s] |
| Flow resistance | |||
| Real | deltaMCon | 0.1 | Fraction of nominal mass flow rate where transition to turbulent occurs |
| Heat Losses | |||
| Boolean | use_conCap | false | =true if using capacitor model for condenser heat loss estimation |
| HeatCapacity | CCon | 0 | Heat capacity of the condenser [J/K] |
| ThermalConductance | GConOut | 0 | Outer thermal conductance for condenser heat loss calculations [W/K] |
| ThermalConductance | GConIns | 0 | Inner thermal conductance for condenser heat loss calculations [W/K] |
| Evaporator | |||
| Dynamics | |||
| Time | tauEva | autCalVEva*rhoEva/autCalMasE... | Evaporator heat transfer time constant at nominal flow [s] |
| Flow resistance | |||
| Real | deltaMEva | 0.1 | Fraction of nominal mass flow rate where transition to turbulent occurs |
| Heat Losses | |||
| Boolean | use_evaCap | false | =true if using capacitor model for evaporator heat loss estimation |
| HeatCapacity | CEva | 0 | Heat capacity of the evaporator [J/K] |
| ThermalConductance | GEvaOut | 0 | Outer thermal conductance for evaporator heat loss calculations [W/K] |
| ThermalConductance | GEvaIns | 0 | Inner thermal conductance for evaporator heat loss calculations [W/K] |
| Initialization | |||
| Parameters | |||
| Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization for refrigerant cycle dynamics (InitialState and InitialOutput are identical) |
| Condenser | |||
| AbsolutePressure | pCon_start | MediumCon.p_default | Start value of pressure [Pa] |
| Temperature | TCon_start | MediumCon.T_default | Start value of temperature [K] |
| Temperature | TConCap_start | MediumCon.T_default | Initial temperature of heat capacity of condenser [K] |
| MassFraction | XCon_start[MediumCon.nX] | MediumCon.X_default | Start value of mass fractions m_i/m [kg/kg] |
| Evaporator | |||
| AbsolutePressure | pEva_start | MediumEva.p_default | Start value of pressure [Pa] |
| Temperature | TEva_start | MediumEva.T_default | Start value of temperature [K] |
| Temperature | TEvaCap_start | MediumEva.T_default | Initial temperature of heat capacity at evaporator [K] |
| MassFraction | XEva_start[MediumEva.nX] | MediumEva.X_default | Start value of mass fractions m_i/m [kg/kg] |
| Dynamics | |||
| Equation | |||
| Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state (only affects fluid-models) |
Connectors
| Type | Name | Description |
|---|---|---|
| FluidPort_a | port_a1 | Fluid connector a1 (positive design flow direction is from port_a1 to port_b1) |
| FluidPort_b | port_b1 | Fluid connector b1 (positive design flow direction is from port_a1 to port_b1) |
| FluidPort_a | port_a2 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) |
| FluidPort_b | port_b2 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) |
| replaceable package MediumCon | Medium on condenser side | |
| replaceable package MediumEva | Medium on evaporator side | |
| input RealInput | ySet | Relative compressor speed between 0 and 1 |
| input RealInput | TEvaAmb | Ambient temperature on the evaporator side [K] |
| input RealInput | TConAmb | Ambient temperature on the condenser side [K] |
| output RealOutput | QCon_flow | Actual heating heat flow rate added to fluid 1 [W] |
| output RealOutput | P | Electric power consumed by compressor [W] |
| output RealOutput | QEva_flow | Actual cooling heat flow rate removed from fluid 2 [W] |
| output RealOutput | EER | Energy efficieny ratio [1] |
| output RealOutput | COP | Coefficient of performance [1] |
| replaceable model RefrigerantCycleChillerCooling | Refrigerant cycle module for the cooling mode | |
| replaceable model RefrigerantCycleChillerHeating | Refrigerant cycle module for the heating mode | |
| input BooleanInput | coo | =true for cooling, =false for heating |
| Inertia | ||
| replaceable model RefrigerantCycleInertia | Inertia between the refrigerant cycle outputs and the heat exchangers. | |
Modelica definition
model LargeScaleWaterToWater "Large scale water to water chiller"
extends Modular(
dpEva_nominal=datTab.dpEva_nominal*scaFac^2,
dpCon_nominal=datTab.dpCon_nominal*scaFac^2,
final dTEva_nominal=-QCoo_flow_nominal/cpEva/mEva_flow_nominal,
final dTCon_nominal=(PEle_nominal - QCoo_flow_nominal)/cpCon/mCon_flow_nominal,
redeclare replaceable package MediumCon = Buildings.Media.Water,
redeclare replaceable package MediumEva = Buildings.Media.Water,
final GEvaIns=0,
final GEvaOut=0,
final CEva=0,
final use_evaCap=false,
final GConIns=0,
final GConOut=0,
final CCon=0,
final TConHea_nominal=0,
final TEvaHea_nominal=0,
final use_conCap=false,
redeclare replaceable Buildings.Fluid.HeatPumps.ModularReversible.Controls.Safety.Data.Wuellhorst2021
safCtrPar
constrainedby Buildings.Fluid.HeatPumps.ModularReversible.Controls.Safety.Data.Generic
(
final tabUppHea=datTab.tabLowBou,
final tabLowCoo=datTab.tabLowBou,
final use_TEvaOutCoo=datTab.use_TEvaOutForOpeEnv,
final use_TConOutCoo=datTab.use_TConOutForOpeEnv),
redeclare model RefrigerantCycleInertia =
Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.Inertias.NoInertia,
redeclare model RefrigerantCycleChillerHeating =
Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.BaseClasses.NoHeating,
redeclare model RefrigerantCycleChillerCooling =
Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.TableData2D (
redeclare Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.Frosting.NoFrosting
iceFacCal, datTab=datTab),
final use_rev=false,
final QHea_flow_nominal=0,
final mCon_flow_nominal=autCalMasCon_flow,
final mEva_flow_nominal=autCalMasEva_flow,
final tauCon=autCalVCon*rhoCon/autCalMasCon_flow,
final tauEva=autCalVEva*rhoEva/autCalMasEva_flow);
final parameter Real scaFac=refCyc.refCycChiCoo.scaFac "Scaling factor of chiller";
extends Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.LargeScaleWaterToWaterDeclarations(
final autCalMasCon_flow=max(5E-5*abs(QCoo_flow_nominal) + 0.3161, autCalMMin_flow),
final autCalMasEva_flow=max(5E-5*abs(QCoo_flow_nominal) - 0.5662, autCalMMin_flow),
final autCalVCon=max(2E-7*abs(QCoo_flow_nominal) - 84E-4, autCalVMin),
final autCalVEva=max(1E-7*abs(QCoo_flow_nominal) - 66E-4, autCalVMin));
replaceable parameter Buildings.Fluid.Chillers.ModularReversible.Data.TableData2D.Generic
datTab constrainedby Data.TableData2D.Generic "Data Table of Chiller";
end LargeScaleWaterToWater;
Buildings.Fluid.Chillers.ModularReversible.Modular
Grey-box model for reversible and non-reversible chillers
Information
Model of a reversible, modular chiller. This models allows combining any of the available modules for refrigerant heating or cooling cycles, inertias, heat losses, and safety controls. All features are optional.
Adding to the partial model (
Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.PartialReversibleRefrigerantMachine),
this model has the coo signal to choose
the operation mode of the chiller.
For more information, see Buildings.Fluid.HeatPumps.ModularReversible.UsersGuide.
Extends from Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.PartialReversibleRefrigerantMachine (Model for reversible heat pumps and chillers with a refrigerant cycle).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package MediumCon | PartialMedium | Medium on condenser side | |
| replaceable package MediumEva | PartialMedium | Medium on evaporator side | |
| Boolean | use_rev | false | =true if the chiller or heat pump is reversible |
| replaceable model RefrigerantCycleChillerCooling | Buildings.Fluid.Chillers.Mod... | Refrigerant cycle module for the cooling mode | |
| replaceable model RefrigerantCycleChillerHeating | Buildings.Fluid.HeatPumps.Mo... | Refrigerant cycle module for the heating mode | |
| Nominal condition | |||
| HeatFlowRate | PEle_nominal | refCyc.refCycChiCoo.PEle_nom... | Nominal electrical power consumption [W] |
| HeatFlowRate | QCoo_flow_nominal | Nominal cooling capcaity [W] | |
| Temperature | TEvaCoo_nominal | Nominal temperature of the cooled fluid [K] | |
| Temperature | TConCoo_nominal | Nominal temperature of the heated fluid [K] | |
| Inertia | |||
| replaceable model RefrigerantCycleInertia | NoInertia | Inertia between the refrigerant cycle outputs and the heat exchangers. | |
| Safety control | |||
| Boolean | use_intSafCtr | true | =true to enable internal safety control |
| Wuellhorst2021 | safCtrPar | redeclare parameter Building... | Safety control parameters |
| Nominal condition - Pressure losses | |||
| TemperatureDifference | dTCon_nominal | Nominal temperature difference in condenser medium, used to calculate mass flow rate [K] | |
| MassFlowRate | mCon_flow_nominal | (PEle_nominal - QCoo_flow_no... | Nominal mass flow rate of the condenser medium [kg/s] |
| PressureDifference | dpCon_nominal | Pressure drop at nominal mass flow rate [Pa] | |
| TemperatureDifference | dTEva_nominal | Nominal temperature difference in evaporator medium, used to calculate mass flow rate [K] | |
| MassFlowRate | mEva_flow_nominal | -QCoo_flow_nominal/(dTEva_no... | Nominal mass flow rate of the evaporator medium [kg/s] |
| PressureDifference | dpEva_nominal | Pressure drop at nominal mass flow rate [Pa] | |
| Nominal condition - Heating | |||
| HeatFlowRate | QHea_flow_nominal | 0 | Nominal heating capacity [W] |
| Temperature | TEvaHea_nominal | Nominal temperature of the heated fluid [K] | |
| Temperature | TConHea_nominal | Nominal temperature of the cooled fluid [K] | |
| Assumptions | |||
| Evaporator | |||
| Boolean | allowFlowReversalEva | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Condenser | |||
| Boolean | allowFlowReversalCon | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Advanced | |||
| Boolean | allowDifferentDeviceIdentifiers | false | if use_rev=true, device data for cooling and heating need to entered. Set allowDifferentDeviceIdentifiers=true to allow different device identifiers devIde |
| Boolean | calEff | true | =false to disable efficiency calculation, may speed up the simulation |
| Real | limWarSca | 0.05 | Allowed difference in scaling '|scaFacHea - scaFacCoo| / scaFacHea', if exceeded, a warning will be issued [1] |
| Diagnostics | |||
| Boolean | show_T | false | = true, if actual temperature at port is computed |
| Real | ySet_small | 0.01 | Threshold for relative speed for the device to be considered on |
| Flow resistance | |||
| Boolean | from_dp | false | = true, use m_flow = f(dp) else dp = f(m_flow) |
| Boolean | linearized | false | = true, use linear relation between m_flow and dp for any flow rate |
| Condenser | |||
| Dynamics | |||
| Time | tauCon | 30 | Condenser heat transfer time constant at nominal flow [s] |
| Flow resistance | |||
| Real | deltaMCon | 0.1 | Fraction of nominal mass flow rate where transition to turbulent occurs |
| Heat Losses | |||
| Boolean | use_conCap | true | =true if using capacitor model for condenser heat loss estimation |
| HeatCapacity | CCon | 0 | Heat capacity of the condenser [J/K] |
| ThermalConductance | GConOut | 0 | Outer thermal conductance for condenser heat loss calculations [W/K] |
| ThermalConductance | GConIns | 0 | Inner thermal conductance for condenser heat loss calculations [W/K] |
| Evaporator | |||
| Dynamics | |||
| Time | tauEva | 30 | Evaporator heat transfer time constant at nominal flow [s] |
| Flow resistance | |||
| Real | deltaMEva | 0.1 | Fraction of nominal mass flow rate where transition to turbulent occurs |
| Heat Losses | |||
| Boolean | use_evaCap | true | =true if using capacitor model for evaporator heat loss estimation |
| HeatCapacity | CEva | 0 | Heat capacity of the evaporator [J/K] |
| ThermalConductance | GEvaOut | 0 | Outer thermal conductance for evaporator heat loss calculations [W/K] |
| ThermalConductance | GEvaIns | 0 | Inner thermal conductance for evaporator heat loss calculations [W/K] |
| Initialization | |||
| Parameters | |||
| Init | initType | Modelica.Blocks.Types.Init.I... | Type of initialization for refrigerant cycle dynamics (InitialState and InitialOutput are identical) |
| Condenser | |||
| AbsolutePressure | pCon_start | MediumCon.p_default | Start value of pressure [Pa] |
| Temperature | TCon_start | MediumCon.T_default | Start value of temperature [K] |
| Temperature | TConCap_start | MediumCon.T_default | Initial temperature of heat capacity of condenser [K] |
| MassFraction | XCon_start[MediumCon.nX] | MediumCon.X_default | Start value of mass fractions m_i/m [kg/kg] |
| Evaporator | |||
| AbsolutePressure | pEva_start | MediumEva.p_default | Start value of pressure [Pa] |
| Temperature | TEva_start | MediumEva.T_default | Start value of temperature [K] |
| Temperature | TEvaCap_start | MediumEva.T_default | Initial temperature of heat capacity at evaporator [K] |
| MassFraction | XEva_start[MediumEva.nX] | MediumEva.X_default | Start value of mass fractions m_i/m [kg/kg] |
| Dynamics | |||
| Equation | |||
| Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Type of energy balance: dynamic (3 initialization options) or steady state (only affects fluid-models) |
Connectors
| Type | Name | Description |
|---|---|---|
| FluidPort_a | port_a1 | Fluid connector a1 (positive design flow direction is from port_a1 to port_b1) |
| FluidPort_b | port_b1 | Fluid connector b1 (positive design flow direction is from port_a1 to port_b1) |
| FluidPort_a | port_a2 | Fluid connector a2 (positive design flow direction is from port_a2 to port_b2) |
| FluidPort_b | port_b2 | Fluid connector b2 (positive design flow direction is from port_a2 to port_b2) |
| input RealInput | ySet | Relative compressor speed between 0 and 1 |
| input RealInput | TEvaAmb | Ambient temperature on the evaporator side [K] |
| input RealInput | TConAmb | Ambient temperature on the condenser side [K] |
| output RealOutput | QCon_flow | Actual heating heat flow rate added to fluid 1 [W] |
| output RealOutput | P | Electric power consumed by compressor [W] |
| output RealOutput | QEva_flow | Actual cooling heat flow rate removed from fluid 2 [W] |
| output RealOutput | EER | Energy efficieny ratio [1] |
| output RealOutput | COP | Coefficient of performance [1] |
| replaceable model RefrigerantCycleChillerCooling | Refrigerant cycle module for the cooling mode | |
| replaceable model RefrigerantCycleChillerHeating | Refrigerant cycle module for the heating mode | |
| input BooleanInput | coo | =true for cooling, =false for heating |
Modelica definition
model Modular
"Grey-box model for reversible and non-reversible chillers"
extends Buildings.Fluid.HeatPumps.ModularReversible.BaseClasses.PartialReversibleRefrigerantMachine
(
final use_COP=use_rev,
final use_EER=true,
con(preDro(m_flow(nominal=-QCoo_flow_nominal/1000/10))),
eva(preDro(m_flow(nominal=-QCoo_flow_nominal/1000/10))),
safCtr(redeclare Buildings.Fluid.Chillers.ModularReversible.Controls.Safety.OperationalEnvelope
opeEnv),
final PEle_nominal=refCyc.refCycChiCoo.PEle_nominal,
mEva_flow_nominal=-QCoo_flow_nominal/(dTEva_nominal*cpEva),
mCon_flow_nominal=(PEle_nominal - QCoo_flow_nominal)/(dTCon_nominal*cpCon),
use_rev=false,
redeclare final Buildings.Fluid.Chillers.ModularReversible.BaseClasses.RefrigerantCycle
refCyc(
redeclare model RefrigerantCycleChillerCooling = RefrigerantCycleChillerCooling,
redeclare model RefrigerantCycleChillerHeating = RefrigerantCycleChillerHeating,
final allowDifferentDeviceIdentifiers=allowDifferentDeviceIdentifiers));
parameter Modelica.Units.SI.HeatFlowRate QCoo_flow_nominal(max=0)
"Nominal cooling capcaity";
parameter Modelica.Units.SI.HeatFlowRate QHea_flow_nominal=0
"Nominal heating capacity";
replaceable model RefrigerantCycleChillerCooling =
Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.BaseClasses.PartialChillerCycle
(PEle_nominal=0)
constrainedby Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.BaseClasses.PartialChillerCycle
(
final useInChi=true,
final TCon_nominal=TConCoo_nominal,
final TEva_nominal=TEvaCoo_nominal,
final QCoo_flow_nominal=QCoo_flow_nominal,
final cpCon=cpCon,
final cpEva=cpEva)
"Refrigerant cycle module for the cooling mode";
replaceable model RefrigerantCycleChillerHeating =
Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.BaseClasses.NoHeating
(PEle_nominal=PEle_nominal)
constrainedby Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.BaseClasses.PartialHeatPumpCycle
(
final useInHeaPum=false,
final TCon_nominal=TEvaHea_nominal,
final TEva_nominal=TConHea_nominal,
final QHea_flow_nominal=QHea_flow_nominal,
final cpCon=cpCon,
final cpEva=cpEva)
"Refrigerant cycle module for the heating mode";
parameter Modelica.Units.SI.Temperature TEvaCoo_nominal
"Nominal temperature of the cooled fluid";
parameter Modelica.Units.SI.Temperature TConCoo_nominal
"Nominal temperature of the heated fluid";
parameter Modelica.Units.SI.Temperature TEvaHea_nominal
"Nominal temperature of the heated fluid";
parameter Modelica.Units.SI.Temperature TConHea_nominal
"Nominal temperature of the cooled fluid";
Modelica.Blocks.Interfaces.BooleanInput coo if not use_busConOnl and use_rev
"=true for cooling, =false for heating";
Modelica.Blocks.Sources.BooleanConstant conCoo(final k=true)
if not use_busConOnl and not use_rev
"Locks the device in cooling mode if designated to be not reversible";
Modelica.Blocks.Logical.Not notCoo "Not cooling is heating";
Modelica.Blocks.Logical.Hysteresis hys(
final uLow=0.001,
final uHigh=ySet_small,
final pre_y_start=false)
"Outputs whether the device is on based on the relative speed";
equation
connect(conCoo.y, sigBus.coo);
connect(coo, sigBus.coo);
connect(eff.QUse_flow, refCycIneEva.y);
connect(eff.hea, notCoo.y);
connect(notCoo.u, sigBus.coo);
connect(hys.y, sigBus.onOffMea);
connect(hys.u, sigBus.yMea);
end Modular;
Buildings.Fluid.Chillers.ModularReversible.Modular.RefrigerantCycleChillerCooling
Refrigerant cycle module for the cooling mode
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| String | devIde | "" | Indicates the data source, used to warn users about different vapor compression devices in reversible models |
| Boolean | useInChi | =false to indicate that this model is used as a heat pump | |
| Nominal condition | |||
| Power | PEle_nominal | 0 | Nominal electrical power consumption [W] |
| Temperature | TCon_nominal | Nominal temperature at secondary condenser side [K] | |
| Temperature | TEva_nominal | Nominal temperature at secondary evaporator side [K] | |
| HeatFlowRate | QCoo_flow_nominal | Nominal cooling capacity [W] | |
| Frosting supression | |||
| NoFrosting | iceFacCal | redeclare Buildings.Fluid.He... | Replaceable model to calculate the icing factor |
| Advanced | |||
| Medium properties | |||
| SpecificHeatCapacity | cpCon | Evaporator medium specific heat capacity [J/(kg.K)] | |
| SpecificHeatCapacity | cpEva | Evaporator medium specific heat capacity [J/(kg.K)] | |
Connectors
| Type | Name | Description |
|---|---|---|
| output RealOutput | PEle | Electrical Power consumed by the device [W] |
| output RealOutput | QCon_flow | Heat flow rate through condenser [W] |
| RefrigerantMachineControlBus | sigBus | Bus-connector |
| output RealOutput | QEva_flow | Heat flow rate through evaporator [W] |
Modelica definition
replaceable model RefrigerantCycleChillerCooling =
Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.BaseClasses.PartialChillerCycle
(PEle_nominal=0)
constrainedby Buildings.Fluid.Chillers.ModularReversible.RefrigerantCycle.BaseClasses.PartialChillerCycle
(
final useInChi=true,
final TCon_nominal=TConCoo_nominal,
final TEva_nominal=TEvaCoo_nominal,
final QCoo_flow_nominal=QCoo_flow_nominal,
final cpCon=cpCon,
final cpEva=cpEva)
"Refrigerant cycle module for the cooling mode";
Buildings.Fluid.Chillers.ModularReversible.Modular.RefrigerantCycleChillerHeating
Refrigerant cycle module for the heating mode
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| String | devIde | "NoHeating" | Indicates the data source, used to warn users about different vapor compression devices in reversible models |
| Boolean | useInHeaPum | =false to indicate that this model is used in a chiller | |
| Nominal condition | |||
| Power | PEle_nominal | PEle_nominal | Nominal electrical power consumption [W] |
| Temperature | TCon_nominal | 273.15 | Nominal temperature at secondary condenser side [K] |
| Temperature | TEva_nominal | 273.15 | Nominal temperature at secondary evaporator side [K] |
| HeatFlowRate | QHea_flow_nominal | 0 | Nominal heating capacity [W] |
| Advanced | |||
| Medium properties | |||
| SpecificHeatCapacity | cpCon | 4184 | Evaporator medium specific heat capacity [J/(kg.K)] |
| SpecificHeatCapacity | cpEva | 4184 | Evaporator medium specific heat capacity [J/(kg.K)] |
Connectors
| Type | Name | Description |
|---|---|---|
| output RealOutput | PEle | Electrical Power consumed by the device [W] |
| output RealOutput | QCon_flow | Heat flow rate through condenser [W] |
| RefrigerantMachineControlBus | sigBus | Bus-connector |
| output RealOutput | QEva_flow | Heat flow rate through evaporator [W] |
Modelica definition
replaceable model RefrigerantCycleChillerHeating =
Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.BaseClasses.NoHeating
(PEle_nominal=PEle_nominal)
constrainedby Buildings.Fluid.HeatPumps.ModularReversible.RefrigerantCycle.BaseClasses.PartialHeatPumpCycle
(
final useInHeaPum=false,
final TCon_nominal=TEvaHea_nominal,
final TEva_nominal=TConHea_nominal,
final QHea_flow_nominal=QHea_flow_nominal,
final cpCon=cpCon,
final cpEva=cpEva)
"Refrigerant cycle module for the heating mode";