Description: "Collection of models that illustrate model use and test models"

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## Buildings.Fluid.Storage.Examples

Collection of models that illustrate model use and test models

### Information

This package contains examples for the use of models that can be found in Buildings.Fluid.Storage.

Extends from Modelica.Icons.ExamplesPackage (Icon for packages containing runnable examples).

### Package Content

Name | Description
--- | ---
ExpansionVessel | Test model for expansion vessel
Stratified | Test model for stratified tank
StratifiedEnhancedInternalHex | Example showing the use of StratifiedEnhancedInternalHex
StratifiedLoadingUnloading | Test model for stratified tank

## Buildings.Fluid.Storage.Examples.ExpansionVessel

Test model for expansion vessel

### Information

This model tests a pressure expansion vessel. The medium model that is used in this example changes its density as a function of temperature. To see the effect of the expansion vessel, delete the connecting line between the volume and the expansion vessel and check how much more the pressure increases as the fluid is heated.

Extends from Modelica.Icons.Example (Icon for runnable examples).

### Modelica definition

model ExpansionVessel "Test model for expansion vessel" extends Modelica.Icons.Example; // package Medium = Modelica.Media.Water.WaterIF97OnePhase_ph "Medium model"; package Medium = Buildings.Media.Water "Medium model"; Buildings.Fluid.Storage.ExpansionVessel expVes( redeclare package Medium = Medium, V_start=1) "Expansion vessel"; Buildings.Fluid.MixingVolumes.MixingVolume vol( redeclare package Medium = Medium, V=1, nPorts=1, m_flow_nominal=0.001, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial) "Volume of water"; Modelica.Blocks.Sources.Pulse pulse( amplitude=20, period=3600, offset=293.15); Buildings.HeatTransfer.Sources.PrescribedTemperature preTem; Modelica.Thermal.HeatTransfer.Components.ThermalConductor theCon(G=10000); equation connect(pulse.y, preTem.T); connect(preTem.port, theCon.port_a); connect(theCon.port_b, vol.heatPort); connect(vol.ports[1], expVes.port_a); end ExpansionVessel;

## Buildings.Fluid.Storage.Examples.Stratified

Test model for stratified tank

### Information

This test model compares two tank models. The only difference between the two tank models is that one uses the third order upwind discretization scheme that reduces numerical diffusion that is induced when connecting volumes in series.

Extends from Modelica.Icons.Example (Icon for runnable examples).

### Modelica definition

model Stratified "Test model for stratified tank" extends Modelica.Icons.Example; package Medium = Buildings.Media.Water "Medium model"; Buildings.Fluid.Storage.Stratified tanSim( redeclare package Medium = Medium, hTan=3, dIns=0.3, nSeg=10, m_flow_nominal=0.1, VTan=3) "Tank"; Modelica.Blocks.Sources.TimeTable TWat(table=[0,273.15 + 40; 3600,273.15 + 40; 3600,273.15 + 20; 7200,273.15 + 20]) "Water temperature"; Buildings.Fluid.Sources.Boundary_pT sou_1( p=300000 + 5000, T=273.15 + 50, redeclare package Medium = Medium, use_T_in=true, nPorts=2); Buildings.Fluid.Sources.Boundary_pT sin_1( redeclare package Medium = Medium, T=273.15 + 20, use_p_in=true, p=300000, nPorts=2); FixedResistances.FixedResistanceDpM res_1( from_dp=true, redeclare package Medium = Medium, dp_nominal=5000, m_flow_nominal=0.1); Buildings.Fluid.Storage.StratifiedEnhanced tanEnh( redeclare package Medium = Medium, hTan=3, dIns=0.3, nSeg=10, m_flow_nominal=0.1, VTan=3) "Tank"; FixedResistances.FixedResistanceDpM res_2( from_dp=true, redeclare package Medium = Medium, dp_nominal=5000, m_flow_nominal=0.1); Buildings.Fluid.Sensors.EnthalpyFlowRate HOut_flow(redeclare package Medium = Medium, m_flow_nominal=0.1) "Enthalpy flow rate"; Buildings.Fluid.Sensors.EnthalpyFlowRate HOut_flow1(redeclare package Medium = Medium, m_flow_nominal=0.1) "Enthalpy flow rate"; Modelica.Blocks.Continuous.Integrator dH "Differenz in enthalpy (should be zero at steady-state)"; Modelica.Blocks.Math.Add add(k2=-1); Modelica.Blocks.Sources.TimeTable P(table=[0,300000; 4200,300000; 4200, 305000; 7200,305000; 7200,310000; 10800,310000; 10800,305000]) "Pressure boundary condition"; Modelica.Blocks.Sources.Sine sine( freqHz=1/86400, amplitude=10, offset=273.15 + 20); Buildings.HeatTransfer.Sources.PrescribedTemperature TBCSid2 "Boundary condition for tank"; Buildings.HeatTransfer.Sources.PrescribedTemperature TBCSid1 "Boundary condition for tank"; Buildings.HeatTransfer.Sources.PrescribedTemperature TBCTop1 "Boundary condition for tank"; Buildings.HeatTransfer.Sources.PrescribedTemperature TBCTop2 "Boundary condition for tank"; equation connect(TWat.y, sou_1.T_in); connect(tanSim.port_b, HOut_flow.port_a); connect(HOut_flow.port_b, res_1.port_a); connect(tanEnh.port_b, HOut_flow1.port_a); connect(HOut_flow1.port_b, res_2.port_a); connect(add.y, dH.u); connect(HOut_flow.H_flow, add.u1); connect(HOut_flow1.H_flow, add.u2); connect(P.y, sin_1.p_in); connect(sine.y, TBCSid1.T); connect(sine.y, TBCTop1.T); connect(sine.y, TBCSid2.T); connect(sine.y, TBCTop2.T); connect(TBCSid2.port, tanEnh.heaPorSid); connect(TBCTop2.port, tanEnh.heaPorTop); connect(sin_1.ports[1], res_1.port_b); connect(sin_1.ports[2], res_2.port_b); connect(sou_1.ports[1], tanSim.port_a); connect(sou_1.ports[2], tanEnh.port_a); connect(TBCSid1.port, tanSim.heaPorSid); connect(TBCTop1.port, tanSim.heaPorTop); end Stratified;

## Buildings.Fluid.Storage.Examples.StratifiedEnhancedInternalHex

Example showing the use of StratifiedEnhancedInternalHex

### Information

This model provides an example of how the Buildings.Fluid.Storage.StratifiedEnhancedInternalHex model can be used. A constant water draw is taken from the tank while a constant flow of hot water is passed through the heat exchanger to heat the water in the tank.

Extends from Modelica.Icons.Example (Icon for runnable examples).

### Modelica definition

model StratifiedEnhancedInternalHex "Example showing the use of StratifiedEnhancedInternalHex" extends Modelica.Icons.Example; package MediumTan = Buildings.Media.Water "Medium in the tank"; package MediumHex = Modelica.Media.Incompressible.Examples.Glycol47 "Medium in the heat exchanger"; Buildings.Fluid.Sources.Boundary_pT hotWatOut( redeclare package Medium = MediumTan, nPorts=1) "Hot water outlet"; Buildings.Fluid.Sources.MassFlowSource_T solColSup( redeclare package Medium = MediumHex, nPorts=1, m_flow=0.278, T=353.15) "Water from solar collector"; Buildings.Fluid.Sources.Boundary_pT toSolCol( redeclare package Medium = MediumHex, nPorts=1, T=283.15) "Water to solar collector"; Buildings.Fluid.Sources.MassFlowSource_T bouCol( redeclare package Medium = MediumTan, use_T_in=false, nPorts=1, m_flow=0.1, T=283.15) "Cold water boundary"; Buildings.Fluid.Storage.StratifiedEnhancedInternalHex tan( redeclare package Medium = MediumTan, m_flow_nominal=0.001, VTan=0.151416, dIns=0.0762, redeclare package MediumHex = MediumHex, CHex=40, Q_flow_nominal=0.278*4200*20, mHex_flow_nominal=0.278, hTan=1.746, hHex_a=0.995, energyDynamicsHex=Modelica.Fluid.Types.Dynamics.FixedInitial, hHex_b=0.1, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, TTan_nominal=293.15, THex_nominal=323.15) "Tank with heat exchanger"; equation connect(solColSup.ports[1], tan.portHex_a); connect(tan.portHex_b, toSolCol.ports[1]); connect(bouCol.ports[1], tan.port_b); connect(hotWatOut.ports[1], tan.port_a); end StratifiedEnhancedInternalHex;

## Buildings.Fluid.Storage.Examples.StratifiedLoadingUnloading

Test model for stratified tank

### Information

This test model compares two tank models. The only difference between the two tank models is that one uses the third order upwind discretization scheme that reduces numerical diffusion that is induced when connecting volumes in series.

Extends from Modelica.Icons.Example (Icon for runnable examples).

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
MassFlowRate | m_flow_nominal | 1*1000/3600/4 | [kg/s]

### Modelica definition

model StratifiedLoadingUnloading "Test model for stratified tank" extends Modelica.Icons.Example; package Medium = Buildings.Media.Water "Medium model"; constant Integer nSeg = 7 "Number of segments in tank"; parameter Modelica.SIunits.MassFlowRate m_flow_nominal= 1*1000/3600/4; Buildings.Fluid.Sources.Boundary_pT sou_1( p=300000 + 5000, T=273.15 + 40, redeclare package Medium = Medium, use_T_in=false, nPorts=2); Sources.MassFlowSource_T sin_1( redeclare package Medium = Medium, T=273.15 + 20, m_flow=-0.028, use_m_flow_in=true, nPorts=1); Buildings.Fluid.Storage.StratifiedEnhanced tanEnh( redeclare package Medium = Medium, hTan=3, dIns=0.3, VTan=0.1, nSeg=nSeg, show_T=true, m_flow_nominal=m_flow_nominal) "Tank"; Sources.MassFlowSource_T sin_2( redeclare package Medium = Medium, T=273.15 + 20, m_flow=-0.028, use_m_flow_in=true, nPorts=1); Buildings.Fluid.Storage.Stratified tan( redeclare package Medium = Medium, hTan=3, dIns=0.3, VTan=0.1, nSeg=nSeg, show_T=true, m_flow_nominal=m_flow_nominal) "Tank"; Modelica.Blocks.Sources.Pulse pulse( amplitude=2*m_flow_nominal, offset=-m_flow_nominal, period=7200); Buildings.Fluid.Sensors.EnthalpyFlowRate HIn_flow(redeclare package Medium = Medium, m_flow_nominal=m_flow_nominal) "Enthalpy flow rate"; Buildings.Fluid.Sensors.EnthalpyFlowRate HOut_flow(redeclare package Medium = Medium, m_flow_nominal=m_flow_nominal) "Enthalpy flow rate"; Buildings.Fluid.Sensors.EnthalpyFlowRate HInEnh_flow(redeclare package Medium = Medium, m_flow_nominal=m_flow_nominal) "Enthalpy flow rate"; Buildings.Fluid.Sensors.EnthalpyFlowRate HOutEnh_flow(redeclare package Medium = Medium, m_flow_nominal=m_flow_nominal) "Enthalpy flow rate"; Modelica.Blocks.Math.Add add(k2=-1); Modelica.Blocks.Continuous.Integrator dHTanEnh "Difference in enthalpy (should be zero at steady-state)"; Modelica.Blocks.Math.Add add1( k2=-1); Modelica.Blocks.Continuous.Integrator dHTan "Difference in enthalpy (should be zero at steady-state)"; equation connect(sou_1.ports[1], HIn_flow.port_a); connect(HIn_flow.port_b, tan.port_a); connect(tan.port_b, HOut_flow.port_a); connect(HOut_flow.port_b, sin_2.ports[1]); connect(sou_1.ports[2], HInEnh_flow.port_a); connect(HInEnh_flow.port_b, tanEnh.port_a); connect(tanEnh.port_b, HOutEnh_flow.port_a); connect(HOutEnh_flow.port_b, sin_1.ports[1]); connect(HInEnh_flow.H_flow, add.u1); connect(HOutEnh_flow.H_flow, add.u2); connect(add.y, dHTanEnh.u); connect(HIn_flow.H_flow, add1.u1); connect(HOut_flow.H_flow, add1.u2); connect(add1.y, dHTan.u); connect(pulse.y, sin_1.m_flow_in); connect(pulse.y, sin_2.m_flow_in); end StratifiedLoadingUnloading;