Buildings.Experimental.DHC.Plants.Cooling.BaseClasses
Package containing base classes
Information
Package containing base classes.Extends from Modelica.Icons.BasesPackage (Icon for packages containing base classes).
Package Content
| Name | Description |
|---|---|
 IdealUser
|
Ideal user model |
 ParallelJunctions
|
A pair of junctions in parallel |
 ParallelPipes
|
CHW supply and return pipes in parallel |
 ReversibleConnection
|
A connection that supports reversible flow with a pump and a valve |
 TankBranch
|
Model of the tank branch of a storage plant |
 Validation
|
Package containing validation models |
Buildings.Experimental.DHC.Plants.Cooling.BaseClasses.IdealUser
Ideal user model
Information
This is a simple ideal user model used by
Buildings.Experimental.DHC.Plants.Cooling.Examples.StoragePlantDualSource.
The load of the user is described by a varying mass flow rate setpoint.
The valve is controlled to maintain the requested mass flow rate.
The model sets its leaving water temperature to the user-specified temperature
T_CHWR_nominal.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package Medium | Modelica.Media.Interfaces.Pa... | Medium package | |
| MassFlowRate | m_flow_nominal | Nominal mass flow rate [kg/s] | |
| Temperature | T_CHWR_nominal | Nominal temperature of CHW return [K] | |
| PressureDifference | dp_nominal | Nominal pressure drop when valve is fully open [Pa] | |
Connectors
| Type | Name | Description |
|---|---|---|
| replaceable package Medium | Medium package | |
| input RealInput | mPre_flow | Load in terms of flow rate prescription [kg/s] |
| output RealOutput | yVal_actual | Consumer control valve actuator position [1] |
| output RealOutput | dp | Differential pressure from the sensor [Pa] |
| FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
| FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
Modelica definition
model IdealUser "Ideal user model"
replaceable package Medium =
Modelica.Media.Interfaces.PartialMedium "Medium package";
parameter Modelica.Units.SI.MassFlowRate m_flow_nominal
"Nominal mass flow rate";
parameter Modelica.Units.SI.Temperature T_CHWR_nominal
"Nominal temperature of CHW return";
parameter Modelica.Units.SI.PressureDifference dp_nominal(
final displayUnit="Pa")
"Nominal pressure drop when valve is fully open";
Buildings.Fluid.Actuators.Valves.TwoWayEqualPercentage val(
redeclare final package Medium = Medium,
final use_inputFilter=true,
final dpValve_nominal=dp_nominal/2,
final init=Modelica.Blocks.Types.Init.InitialState,
final dpFixed_nominal=dp_nominal/2,
final m_flow_nominal=m_flow_nominal,
y_start=0) "User control valve";
Buildings.Controls.Continuous.LimPID conPI(
controllerType=Modelica.Blocks.Types.SimpleController.PI,
k=0.5,
Ti=20,
final reverseActing=true) "PI controller";
Modelica.Blocks.Interfaces.RealInput mPre_flow(
final quantity = "MassFlowRate",
final unit = "kg/s")
"Load in terms of flow rate prescription";
Modelica.Blocks.Interfaces.RealOutput yVal_actual(
final unit = "1")
"Consumer control valve actuator position";
Buildings.Fluid.Sensors.RelativePressure senRelPre(
redeclare final package Medium = Medium)
"Differential pressure sensor";
Modelica.Blocks.Interfaces.RealOutput dp(
final quantity="PressureDifference",
final unit="Pa",
displayUnit="Pa")
"Differential pressure from the sensor";
Modelica.Fluid.Interfaces.FluidPort_a port_a(
p(start=Medium.p_default),
redeclare final package Medium = Medium,
h_outflow(start=Medium.h_default, nominal=Medium.h_default))
"Fluid connector a (positive design flow direction is from port_a to port_b)";
Modelica.Fluid.Interfaces.FluidPort_b port_b(
p(start=Medium.p_default),
redeclare final package Medium = Medium,
h_outflow(start=Medium.h_default, nominal=Medium.h_default))
"Fluid connector b (positive design flow direction is from port_a to port_b)";
Buildings.Fluid.Sensors.MassFlowRate senMasFlo(
redeclare final package Medium = Medium)
"Mass flow rate sensor";
Buildings.Fluid.Sources.PropertySource_T proSou(
redeclare final package Medium = Medium,
final use_T_in=true) "Ideal temperature source";
Modelica.Blocks.Sources.Constant TRet(final k=T_CHWR_nominal)
"Constant CHW return temperature";
equation
connect(senRelPre.p_rel, dp);
connect(val.y_actual, yVal_actual);
connect(senRelPre.port_a, port_a);
connect(senRelPre.port_b, port_b);
connect(conPI.y, val.y);
connect(senMasFlo.port_b, port_b);
connect(senMasFlo.m_flow, conPI.u_m);
connect(port_a, val.port_a);
connect(conPI.u_s, mPre_flow);
connect(senMasFlo.port_a, proSou.port_b);
connect(proSou.port_a, val.port_b);
connect(TRet.y, proSou.T_in);
end IdealUser;
Buildings.Experimental.DHC.Plants.Cooling.BaseClasses.ParallelJunctions
A pair of junctions in parallel
Information
This model provides junction models in parallel on the distribution pipe lines. This model is for breaking algebraic loops only and has no pressure drop.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package Medium | Modelica.Media.Interfaces.Pa... | Medium package | |
| Nominal condition | |||
| MassFlowRate | m_flow_nominal | Design mass flow rate (used to approximate dynamics [kg/s] | |
| Dynamics | |||
| Nominal condition | |||
| Time | tau | 30 | Time constant at nominal flow [s] |
| Initialization | |||
| Temperature | T1_start | Medium.T_default | Start temperature of the volume [K] |
| Temperature | T2_start | Medium.T_default | Start temperature of the volume [K] |
Connectors
| Type | Name | Description |
|---|---|---|
| replaceable package Medium | Medium package | |
| FluidPort_a | port_a2 | Fluid connector |
| FluidPort_b | port_b1 | Fluid connector |
| FluidPort_b | port_b2 | Fluid connector |
| FluidPort_a | port_a1 | Fluid connector |
| FluidPort_a | port_c1 | Fluid connector |
| FluidPort_b | port_c2 | Fluid connector |
Modelica definition
model ParallelJunctions "A pair of junctions in parallel"
replaceable package Medium =
Modelica.Media.Interfaces.PartialMedium "Medium package";
parameter Modelica.Units.SI.MassFlowRate m_flow_nominal
"Design mass flow rate (used to approximate dynamics";
parameter Modelica.Units.SI.Time tau=30 "Time constant at nominal flow";
parameter Modelica.Units.SI.Temperature T1_start=Medium.T_default
"Start temperature of the volume";
parameter Modelica.Units.SI.Temperature T2_start=Medium.T_default
"Start temperature of the volume";
Modelica.Fluid.Interfaces.FluidPort_a port_a2(
redeclare final package Medium = Medium,
p(final displayUnit="Pa")) "Fluid connector";
Modelica.Fluid.Interfaces.FluidPort_b port_b1(
redeclare final package Medium = Medium,
p(final displayUnit="Pa")) "Fluid connector";
Modelica.Fluid.Interfaces.FluidPort_b port_b2(
redeclare final package Medium = Medium,
p(final displayUnit="Pa")) "Fluid connector";
Modelica.Fluid.Interfaces.FluidPort_a port_a1(
redeclare final package Medium = Medium,
p(final displayUnit="Pa")) "Fluid connector";
Modelica.Fluid.Interfaces.FluidPort_a port_c1(
redeclare final package Medium = Medium,
p(final displayUnit="Pa")) "Fluid connector";
Modelica.Fluid.Interfaces.FluidPort_b port_c2(
redeclare final package Medium = Medium,
p(final displayUnit="Pa")) "Fluid connector";
Buildings.Fluid.FixedResistances.Junction jun1(
redeclare final package Medium = Medium,
energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
final tau=tau,
final T_start=T1_start,
final m_flow_nominal={-m_flow_nominal,-m_flow_nominal,m_flow_nominal},
final dp_nominal={0,0,0})
"Junction";
Buildings.Fluid.FixedResistances.Junction jun2(
redeclare final package Medium = Medium,
energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
final tau=tau,
final T_start=T2_start,
final m_flow_nominal={m_flow_nominal,m_flow_nominal,-m_flow_nominal},
final dp_nominal={0,0,0})
"Junction";
equation
connect(port_a1, jun1.port_1);
connect(jun1.port_3,port_c1);
connect(jun1.port_2, port_b1);
connect(port_b2, jun2.port_1);
connect(jun2.port_2, port_a2);
connect(jun2.port_3,port_c2);
end ParallelJunctions;
Buildings.Experimental.DHC.Plants.Cooling.BaseClasses.ParallelPipes
CHW supply and return pipes in parallel
Information
This model contains two pipes in parallel that represent the supply and return pipes of a district CHW network. Only pressure drop is considered. This model does not consider heat loss.
Extends from Buildings.Fluid.Interfaces.PartialFourPortInterface (Partial model transporting fluid between two ports without storing mass or energy).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package Medium1 | PartialMedium | Medium 1 in the component | |
| replaceable package Medium2 | PartialMedium | Medium 2 in the component | |
| replaceable package Medium | Modelica.Media.Interfaces.Pa... | Medium package | |
| Nominal condition | |||
| MassFlowRate | m1_flow_nominal | m_flow_nominal | Nominal mass flow rate [kg/s] |
| MassFlowRate | m2_flow_nominal | m_flow_nominal | Nominal mass flow rate [kg/s] |
| MassFlowRate | m_flow_nominal | Nominal mass flow rate [kg/s] | |
| PressureDifference | dp_nominal | Nominal pressure drop [Pa] | |
| Assumptions | |||
| Boolean | allowFlowReversal1 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium 1 |
| Boolean | allowFlowReversal2 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium 2 |
| Advanced | |||
| MassFlowRate | m1_flow_small | 1E-4*abs(m1_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
| MassFlowRate | m2_flow_small | 1E-4*abs(m2_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
| Diagnostics | |||
| Boolean | show_T | false | = true, if actual temperature at port is computed |
Connectors
| Type | Name | Description |
|---|---|---|
| replaceable package Medium1 | Medium 1 in the component | |
| replaceable package Medium2 | Medium 2 in the component | |
| 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 Medium | Medium package | |
Modelica definition
model ParallelPipes "CHW supply and return pipes in parallel"
extends Buildings.Fluid.Interfaces.PartialFourPortInterface(
redeclare final package Medium1 = Medium,
redeclare final package Medium2 = Medium,
final m1_flow_nominal = m_flow_nominal,
final m2_flow_nominal = m_flow_nominal);
replaceable package Medium =
Modelica.Media.Interfaces.PartialMedium "Medium package";
parameter Modelica.Units.SI.MassFlowRate m_flow_nominal
"Nominal mass flow rate";
parameter Modelica.Units.SI.PressureDifference dp_nominal(
final displayUnit="Pa")
"Nominal pressure drop";
Buildings.Fluid.FixedResistances.PressureDrop preDro1(
redeclare package Medium = Medium1,
final allowFlowReversal=true,
final dp_nominal=dp_nominal,
final m_flow_nominal=m1_flow_nominal) "Flow resistance";
Buildings.Fluid.FixedResistances.PressureDrop preDro2(
redeclare package Medium = Medium2,
final allowFlowReversal=true,
final dp_nominal=dp_nominal,
final m_flow_nominal=m2_flow_nominal) "Flow resistance";
equation
connect(preDro1.port_a, port_a1);
connect(preDro1.port_b, port_b1);
connect(preDro2.port_a, port_a2);
connect(preDro2.port_b, port_b2);
end ParallelPipes;
Buildings.Experimental.DHC.Plants.Cooling.BaseClasses.ReversibleConnection
A connection that supports reversible flow with a pump and a valve
Information
This model implements a piping connection for reversible mass flow rate between the storage plant and the district network.
Extends from Buildings.Fluid.Interfaces.PartialTwoPortInterface (Partial model transporting fluid between two ports without storing mass or energy).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package Medium | PartialMedium | Medium in the component | |
| MassFlowRate | mTan_flow_nominal | Nominal mass flow rate for CHW tank branch [kg/s] | |
| PressureDifference | dpPum_nominal | Nominal pressure difference for supply pump sizing [Pa] | |
| PressureDifference | dpVal_nominal | Nominal pressure difference for return valve sizing [Pa] | |
| Nominal condition | |||
| MassFlowRate | m_flow_nominal | Nominal mass flow rate [kg/s] | |
| Assumptions | |||
| Boolean | allowFlowReversal | true | = false to simplify equations, assuming, but not enforcing, no flow reversal |
| Advanced | |||
| MassFlowRate | m_flow_small | 1E-4*abs(m_flow_nominal) | Small mass flow rate for regularization of zero flow [kg/s] |
| Diagnostics | |||
| Boolean | show_T | false | = true, if actual temperature at port is computed |
| Initialization | |||
| ThermodynamicTemperature | T_start | Start temperature [K] | |
Connectors
| Type | Name | Description |
|---|---|---|
| FluidPort_a | port_a | Fluid connector a (positive design flow direction is from port_a to port_b) |
| FluidPort_b | port_b | Fluid connector b (positive design flow direction is from port_a to port_b) |
| output RealOutput | PEle | Estimated power consumption [W] |
| input RealInput | yPum | Normalized speed signal for pump [1] |
| input RealInput | yVal | Normalized flow signal for valve [1] |
Modelica definition
model ReversibleConnection
"A connection that supports reversible flow with a pump and a valve"
extends Buildings.Fluid.Interfaces.PartialTwoPortInterface(
final allowFlowReversal=true);
parameter Modelica.Units.SI.MassFlowRate mTan_flow_nominal(min=0)
"Nominal mass flow rate for CHW tank branch";
parameter Modelica.Units.SI.PressureDifference dpPum_nominal
"Nominal pressure difference for supply pump sizing";
parameter Modelica.Units.SI.PressureDifference dpVal_nominal
"Nominal pressure difference for return valve sizing";
parameter Modelica.Units.SI.ThermodynamicTemperature T_start
"Start temperature";
Modelica.Blocks.Interfaces.RealOutput PEle(
final quantity="Power",
final unit="W")
"Estimated power consumption";
Modelica.Blocks.Interfaces.RealInput yPum(final unit="1")
"Normalized speed signal for pump";
Buildings.Fluid.Movers.Preconfigured.SpeedControlled_y pum(
redeclare final package Medium = Medium,
final m_flow_nominal=m_flow_nominal,
final addPowerToMedium=false,
final dp_nominal=dpPum_nominal) "Supply pump";
Buildings.Fluid.FixedResistances.CheckValve cheVal(
redeclare final package Medium = Medium,
final m_flow_nominal=m_flow_nominal,
final dpValve_nominal=0.1*dpPum_nominal,
final dpFixed_nominal=0) "Check valve";
Buildings.Fluid.Actuators.Valves.TwoWayPressureIndependent val(
redeclare final package Medium = Medium,
final m_flow_nominal=mTan_flow_nominal,
final dpValve_nominal=dpVal_nominal,
y_start=0)
"Valve that throttles CHW from the supply line to the tank";
Modelica.Blocks.Interfaces.RealInput yVal(final unit="1")
"Normalized flow signal for valve";
protected
Buildings.Fluid.FixedResistances.Junction jun1(
redeclare final package Medium = Medium,
energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
tau=30,
T_start=T_start,
m_flow_nominal={-mTan_flow_nominal,m_flow_nominal,-m_flow_nominal},
dp_nominal={0,0,0}) "Junction";
Buildings.Fluid.FixedResistances.Junction jun2(
redeclare final package Medium = Medium,
energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
tau=30,
T_start=T_start,
m_flow_nominal={-m_flow_nominal,-mTan_flow_nominal,m_flow_nominal},
dp_nominal={0,0,0}) "Junction";
equation
connect(pum.port_b, jun2.port_1);
connect(jun2.port_3, port_b);
connect(val.port_a, jun2.port_2);
connect(jun1.port_3, port_a);
connect(jun1.port_1, val.port_b);
connect(pum.y, yPum);
connect(yVal, val.y);
connect(pum.P, PEle);
connect(jun1.port_2, cheVal.port_a);
connect(cheVal.port_b, pum.port_a);
end ReversibleConnection;
Buildings.Experimental.DHC.Plants.Cooling.BaseClasses.TankBranch
Model of the tank branch of a storage plant
Information
This model is part of a storage plant. This branch has a stratified tank. This tank can potentially be charged remotely by a chiller from the district CHW network, or by a chiller that is local to the energy transfer station that contains this tank.
Extends from Buildings.Fluid.Interfaces.PartialFourPort (Partial model with four ports).
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| replaceable package Medium1 | PartialMedium | Medium 1 in the component | |
| replaceable package Medium2 | PartialMedium | Medium 2 in the component | |
| replaceable package Medium | Modelica.Media.Interfaces.Pa... | Medium package | |
| Nominal values | |||
| MassFlowRate | m_flow_nominal | Nominal mass flow rate [kg/s] | |
| MassFlowRate | mTan_flow_nominal | Nominal mass flow rate for CHW tank branch [kg/s] | |
| MassFlowRate | mChi_flow_nominal | Nominal mass flow rate for CHW chiller branch [kg/s] | |
| Temperature | T_CHWS_nominal | 7 + 273.15 | Nominal temperature of CHW supply [K] |
| Temperature | T_CHWR_nominal | 12 + 273.15 | Nominal temperature of CHW return [K] |
| Tank | |||
| Volume | VTan | Tank volume [m3] | |
| Length | hTan | Height of tank (without insulation) [m] | |
| Length | dIns | Thickness of insulation [m] | |
| ThermalConductivity | kIns | 0.04 | Specific heat conductivity of insulation [W/(m.K)] |
| Integer | nSeg | 5 | Number of volume segments |
| Time | tau | 1 | Time constant for mixing [s] |
| Assumptions | |||
| Boolean | allowFlowReversal1 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium 1 |
| Boolean | allowFlowReversal2 | true | = false to simplify equations, assuming, but not enforcing, no flow reversal for medium 2 |
| Dynamics | |||
| Conservation equations | |||
| Dynamics | energyDynamics | Modelica.Fluid.Types.Dynamic... | Formulation of energy balance |
| Initialization | |||
| AbsolutePressure | p_start | Medium.p_default | Start value of pressure [Pa] |
| Temperature | T_start | T_CHWR_nominal | Start value of temperature [K] |
| Temperature | TFlu_start[nSeg] | T_start*ones(nSeg) | Initial temperature of the tank segments, with TFlu_start[1] being the top segment [K] |
Connectors
| Type | Name | Description |
|---|---|---|
| replaceable package Medium1 | Medium 1 in the component | |
| replaceable package Medium2 | Medium 2 in the component | |
| 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 Medium | Medium package | |
| output RealOutput | mTan_flow | Mass flow rate of the tank [kg/s] |
| output RealOutput | Ql_flow | Heat loss of tank (positive if heat flows from tank to ambient) [W] |
| HeatPort_a | heaPorTop | Heat port tank top (outside insulation) |
| HeatPort_a | heaPorSid | Heat port tank side (outside insulation) |
| HeatPort_a | heaPorBot | Heat port tank bottom (outside insulation). Leave unconnected for adiabatic condition |
| HeatPort_a | heaPorVol[tan.nSeg] | Heat port that connects to the control volumes of the tank |
| output RealOutput | TTan[2] | Temperatures at the tank 1: top and 2: bottom [K] |
Modelica definition
model TankBranch "Model of the tank branch of a storage plant"
extends Buildings.Fluid.Interfaces.PartialFourPort(
redeclare final package Medium1 = Medium,
redeclare final package Medium2 = Medium);
replaceable package Medium =
Modelica.Media.Interfaces.PartialMedium "Medium package";
parameter Modelica.Units.SI.MassFlowRate m_flow_nominal(min=0)
"Nominal mass flow rate";
parameter Modelica.Units.SI.MassFlowRate mTan_flow_nominal(min=0)
"Nominal mass flow rate for CHW tank branch";
parameter Modelica.Units.SI.MassFlowRate mChi_flow_nominal(min=0)
"Nominal mass flow rate for CHW chiller branch";
parameter Modelica.Units.SI.Temperature T_CHWS_nominal(displayUnit="degC")=
7+273.15 "Nominal temperature of CHW supply";
parameter Modelica.Units.SI.Temperature T_CHWR_nominal(displayUnit="degC")=
12+273.15
"Nominal temperature of CHW return";
// Storage tank parameters
parameter Modelica.Units.SI.Volume VTan "Tank volume";
parameter Modelica.Units.SI.Length hTan
"Height of tank (without insulation)";
parameter Modelica.Units.SI.Length dIns "Thickness of insulation";
parameter Modelica.Units.SI.ThermalConductivity kIns=0.04
"Specific heat conductivity of insulation";
parameter Integer nSeg(min=2) = 5 "Number of volume segments";
parameter Modelica.Fluid.Types.Dynamics energyDynamics=
Modelica.Fluid.Types.Dynamics.FixedInitial
"Formulation of energy balance";
parameter Medium.AbsolutePressure p_start = Medium.p_default
"Start value of pressure";
parameter Medium.Temperature T_start=T_CHWR_nominal
"Start value of temperature";
parameter Modelica.Units.SI.Temperature TFlu_start[nSeg]=T_start*ones(nSeg)
"Initial temperature of the tank segments, with TFlu_start[1] being the top segment";
parameter Modelica.Units.SI.Time tau=1 "Time constant for mixing";
Buildings.Fluid.Storage.Stratified tan(
redeclare final package Medium = Medium,
final allowFlowReversal=true,
final VTan=VTan,
final hTan=hTan,
final dIns=dIns,
final kIns=kIns,
final nSeg=nSeg,
final energyDynamics=energyDynamics,
final p_start=p_start,
final T_start=T_start,
final TFlu_start=TFlu_start,
final tau=tau,
final m_flow_nominal=mTan_flow_nominal,
show_T=true) "Tank";
Buildings.Fluid.Sensors.MassFlowRate senFlo(
redeclare final package Medium = Medium,
final allowFlowReversal=true) "Flow rate sensor for the tank,";
Modelica.Blocks.Interfaces.RealOutput mTan_flow(
final quantity="MassFlowRate",
final unit="kg/s") "Mass flow rate of the tank";
Modelica.Blocks.Interfaces.RealOutput Ql_flow(
final quantity="HeatFlowRate",
final unit="W")
"Heat loss of tank (positive if heat flows from tank to ambient)";
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a heaPorTop
"Heat port tank top (outside insulation)";
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a heaPorSid
"Heat port tank side (outside insulation)";
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a heaPorBot
"Heat port tank bottom (outside insulation). Leave unconnected for adiabatic condition";
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[tan.nSeg] heaPorVol
"Heat port that connects to the control volumes of the tank";
Modelica.Blocks.Interfaces.RealOutput TTan[2](
each unit="K",
each final quantity="Temperature",
each displayUnit="degC") "Temperatures at the tank 1: top and 2: bottom";
Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensor senTemTop
"Temperature sensor for tank top";
Modelica.Thermal.HeatTransfer.Sensors.TemperatureSensor senTemBot
"Temperature sensor for tank bottom";
protected
Buildings.Fluid.FixedResistances.Junction junSup(
redeclare final package Medium = Medium,
energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
T_start=T_CHWS_nominal,
tau=30,
m_flow_nominal={-mChi_flow_nominal,mTan_flow_nominal,m_flow_nominal},
dp_nominal={0,0,0}) "Junction on the supply side";
Buildings.Fluid.FixedResistances.Junction junRet(
redeclare final package Medium = Medium,
energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial,
T_start=T_CHWR_nominal,
tau=30,
m_flow_nominal={-m_flow_nominal,mChi_flow_nominal,mTan_flow_nominal},
dp_nominal={0,0,0}) "Junction on the return side";
equation
connect(senFlo.m_flow, mTan_flow);
connect(tan.Ql_flow, Ql_flow);
connect(tan.heaPorTop, heaPorTop);
connect(tan.heaPorSid, heaPorSid);
connect(tan.heaPorBot, heaPorBot);
connect(heaPorVol, tan.heaPorVol);
connect(junRet.port_3, senFlo.port_a);
connect(senFlo.port_b, tan.port_a);
connect(tan.port_b, junSup.port_3);
connect(tan.heaPorTop, senTemTop.port);
connect(tan.heaPorBot, senTemBot.port);
connect(senTemTop.T, TTan[1]);
connect(senTemBot.T, TTan[2]);
connect(port_b2, junRet.port_2);
connect(junRet.port_1, port_a2);
connect(junSup.port_2, port_b1);
connect(junSup.port_1, port_a1);
end TankBranch;