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

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## Buildings.Fluid.FixedResistances.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.FixedResistances.

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

### Package Content

Name | Description
--- | ---
FixedResistance | Test model for the fixed resistance model
FixedResistancesExplicit | Test of multiple resistances in series
FixedResistancesParallel |
FixedResistancesSeries | Test of multiple resistances in series
Pipe | Test of a pipe with multiple segments
SplitterFixedResistanceDpM | Test model for the three way splitter/mixer model

## Buildings.Fluid.FixedResistances.Examples.FixedResistance

Test model for the fixed resistance model

### Information

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

### Modelica definition

model FixedResistance "Test model for the fixed resistance model" extends Modelica.Icons.Example; package Medium = Buildings.Media.Water; Modelica.Blocks.Sources.Constant PAtm(k=101325); Modelica.Blocks.Sources.Ramp P( duration=1, height=20, offset=101315); Buildings.Fluid.FixedResistances.FixedResistanceDpM res1( redeclare package Medium = Medium, from_dp=true, m_flow_nominal=5, dp_nominal=10); Buildings.Fluid.Sources.Boundary_pT sou1( redeclare package Medium = Medium, use_p_in=true, T=293.15, nPorts=3); Buildings.Fluid.Sources.Boundary_pT sin1( redeclare package Medium = Medium, T=283.15, use_p_in=true, nPorts=3); Buildings.Fluid.FixedResistances.FixedResistanceDpM res2( redeclare package Medium = Medium, from_dp=true, m_flow_nominal=5, dp_nominal=10, use_dh=true); Buildings.Fluid.FixedResistances.FixedResistanceDpM res3( redeclare package Medium = Medium, from_dp=true, m_flow_nominal=5, dp_nominal=10, use_dh=true); FixedResistances.LosslessPipe pipCon(redeclare package Medium = Medium, m_flow_nominal=5) "Lossless pipe connection"; Buildings.Fluid.Sensors.MassFlowRate masFlo2(redeclare package Medium = Medium) "Mass flow rate sensor"; Buildings.Fluid.Sensors.MassFlowRate masFlo3(redeclare package Medium = Medium) "Mass flow rate sensor"; Buildings.Utilities.Diagnostics.AssertEquality assEqu(threShold=1E-4, message= "Inputs differ, check that lossless pipe is correctly implemented.") "Assert equality of the two mass flow rates"; equation connect(res2.port_b, masFlo2.port_a); connect(res3.port_b, masFlo3.port_a); connect(masFlo3.port_b, pipCon.port_a); connect(P.y, sou1.p_in); connect(sou1.ports[1], res1.port_a); connect(sin1.ports[1], res1.port_b); connect(masFlo3.m_flow, assEqu.u1); connect(masFlo2.m_flow, assEqu.u2); connect(PAtm.y, sin1.p_in); connect(sou1.ports[2], res2.port_a); connect(sou1.ports[3], res3.port_a); connect(sin1.ports[2], masFlo2.port_b); connect(sin1.ports[3], pipCon.port_b); end FixedResistance;

## Buildings.Fluid.FixedResistances.Examples.FixedResistancesExplicit

Test of multiple resistances in series

### Information

This model tests whether inverse functions are being used by the code translator. In Dymola 7.2, there should only be one non-linear equation system in one variable after the symbolic manipulations.

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

### Modelica definition

model FixedResistancesExplicit "Test of multiple resistances in series" extends Modelica.Icons.Example; package Medium = Buildings.Media.Air; Buildings.Fluid.Sources.Boundary_ph sou( redeclare package Medium = Medium, nPorts=1, p(displayUnit="Pa") = 101335, use_p_in=true); Buildings.Fluid.Sources.Boundary_ph sin( redeclare package Medium = Medium, nPorts=1, use_p_in=false, p=101325); Buildings.Fluid.FixedResistances.FixedResistanceDpM res11( redeclare package Medium = Medium, from_dp=false, m_flow_nominal=2, dp_nominal=5); Buildings.Fluid.FixedResistances.FixedResistanceDpM res12( redeclare package Medium = Medium, from_dp=false, m_flow_nominal=2, dp_nominal=5); Buildings.Fluid.FixedResistances.FixedResistanceDpM res22( redeclare package Medium = Medium, m_flow_nominal=2, dp_nominal=5, from_dp=true); Buildings.Fluid.FixedResistances.FixedResistanceDpM res21( redeclare package Medium = Medium, m_flow_nominal=2, dp_nominal=5, from_dp=true); Buildings.Fluid.FixedResistances.FixedResistanceDpM res31( redeclare package Medium = Medium, from_dp=false, m_flow_nominal=2, dp_nominal=5); Buildings.Fluid.FixedResistances.FixedResistanceDpM res32( redeclare package Medium = Medium, from_dp=false, m_flow_nominal=2, dp_nominal=5); Buildings.Fluid.FixedResistances.FixedResistanceDpM res42( redeclare package Medium = Medium, m_flow_nominal=2, dp_nominal=5, from_dp=true); Buildings.Fluid.FixedResistances.FixedResistanceDpM res41( redeclare package Medium = Medium, m_flow_nominal=2, dp_nominal=5, from_dp=true); Buildings.Fluid.Sources.MassFlowSource_h bou( redeclare package Medium = Medium, m_flow=1, nPorts=1); Buildings.Fluid.Sources.MassFlowSource_h bou1( redeclare package Medium = Medium, m_flow=1, nPorts=1); Buildings.Fluid.Sources.Boundary_pT sin1( redeclare package Medium = Medium, T=273.15 + 10, nPorts=2, use_p_in=false, p=101325); Buildings.Fluid.Sources.Boundary_ph sin2( redeclare package Medium = Medium, nPorts=1, use_p_in=false, p=101325); Buildings.Fluid.Sources.Boundary_ph sou1( redeclare package Medium = Medium, nPorts=1, p(displayUnit="Pa") = 101335, use_p_in=true); Modelica.Blocks.Sources.Ramp P( duration=1, height=20, offset=101315); Buildings.Fluid.Sensors.MassFlowRate senMasFlo1(redeclare package Medium = Medium) "Mass flow rate sensor"; Buildings.Fluid.Sensors.MassFlowRate senMasFlo2(redeclare package Medium = Medium) "Mass flow rate sensor"; Buildings.Fluid.Sensors.MassFlowRate senMasFlo3(redeclare package Medium = Medium) "Mass flow rate sensor"; Buildings.Fluid.Sensors.MassFlowRate senMasFlo4(redeclare package Medium = Medium) "Mass flow rate sensor"; Buildings.Utilities.Diagnostics.AssertEquality assertEquality(threShold=1E-1); Buildings.Utilities.Diagnostics.AssertEquality assertEquality1(threShold=1E-1); equation connect(res11.port_b, res12.port_a); connect(res21.port_b, res22.port_a); connect(res31.port_b, res32.port_a); connect(res41.port_b, res42.port_a); connect(sou.ports[1], res11.port_a); connect(bou.ports[1], res31.port_a); connect(bou1.ports[1], res41.port_a); connect(sou1.ports[1], res21.port_a); connect(P.y, sou.p_in); connect(P.y, sou1.p_in); connect(res12.port_b, senMasFlo1.port_a); connect(res22.port_b, senMasFlo2.port_a); connect(res32.port_b, senMasFlo3.port_a); connect(res42.port_b, senMasFlo4.port_a); connect(senMasFlo3.port_b, sin1.ports[1]); connect(senMasFlo4.port_b, sin1.ports[2]); connect(senMasFlo1.port_b, sin.ports[1]); connect(senMasFlo2.port_b, sin2.ports[1]); connect(senMasFlo3.m_flow, assertEquality1.u1); connect(senMasFlo4.m_flow, assertEquality1.u2); connect(senMasFlo1.m_flow, assertEquality.u1); connect(senMasFlo2.m_flow, assertEquality.u2); end FixedResistancesExplicit;

## Buildings.Fluid.FixedResistances.Examples.FixedResistancesParallel

### Information

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

### Modelica definition

model FixedResistancesParallel extends Modelica.Icons.Example; package Medium = Buildings.Media.Water; Modelica.Blocks.Sources.Constant PAtm(k=101325); Modelica.Blocks.Sources.Ramp P( duration=1, height=20, offset=101315); Buildings.Fluid.FixedResistances.FixedResistanceDpM res1( redeclare package Medium = Medium, m_flow_nominal=5, dp_nominal=10, deltaM=0.3, linearized=false, from_dp=false); Buildings.Fluid.Sources.Boundary_pT sou1( redeclare package Medium = Medium, T=293.15, nPorts=2, use_p_in=true); Buildings.Fluid.Sources.Boundary_pT sin1( redeclare package Medium = Medium, T=283.15, nPorts=2, use_p_in=true); Buildings.Fluid.FixedResistances.FixedResistanceDpM res2( redeclare package Medium = Medium, m_flow_nominal=5, dp_nominal=10, deltaM=0.3, linearized=false, from_dp=false); Buildings.Fluid.Sensors.MassFlowRate masFlo2(redeclare package Medium = Medium) "Mass flow rate sensor"; Buildings.Utilities.Diagnostics.AssertEquality assEqu(threShold=1E-4, message= "Inputs differ, check that lossless pipe is correctly implemented.") "Assert equality of the two mass flow rates"; Buildings.Fluid.Sensors.MassFlowRate masFlo1(redeclare package Medium = Medium) "Mass flow rate sensor"; equation connect(PAtm.y, sin1.p_in); connect(P.y, sou1.p_in); connect(res2.port_b, masFlo2.port_a); connect(res1.port_b, masFlo1.port_a); connect(sou1.ports[1], res1.port_a); connect(sou1.ports[2], res2.port_a); connect(sin1.ports[1], masFlo1.port_b); connect(sin1.ports[2], masFlo2.port_b); connect(masFlo2.m_flow, assEqu.u1); connect(masFlo1.m_flow, assEqu.u2); end FixedResistancesParallel;

## Buildings.Fluid.FixedResistances.Examples.FixedResistancesSeries

Test of multiple resistances in series

### Information

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

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
Pressure | dp_nominal | 5 | Nominal pressure drop for each resistance [Pa]
Integer | nRes | 10 | Number of resistances

### Modelica definition

model FixedResistancesSeries "Test of multiple resistances in series" extends Modelica.Icons.Example; package Medium = Buildings.Media.Air; Modelica.Blocks.Sources.Constant PAtm(k=101325); parameter Modelica.SIunits.Pressure dp_nominal = 5 "Nominal pressure drop for each resistance"; Modelica.Blocks.Sources.Ramp P( duration=1, height=2*dp_nominal*nRes, offset=101325 - dp_nominal*nRes); Buildings.Fluid.Sources.Boundary_pT sou( redeclare package Medium = Medium, T=273.15 + 20, use_p_in=true, nPorts=1); Buildings.Fluid.Sources.Boundary_pT sin( redeclare package Medium = Medium, T=273.15 + 10, use_p_in=true, nPorts=1); parameter Integer nRes( min=2) = 10 "Number of resistances"; Buildings.Fluid.FixedResistances.FixedResistanceDpM[ nRes] res( redeclare each package Medium = Medium, each dp_nominal=dp_nominal, each from_dp = false, each m_flow_nominal=2); equation for i in 1:nRes-1 loop connect(res[i].port_b, res[i+1].port_a); end for; connect(PAtm.y, sin.p_in); connect(P.y, sou.p_in); connect(sin.ports[1], res[nRes].port_b); connect(sou.ports[1], res[1].port_a); end FixedResistancesSeries;

## Buildings.Fluid.FixedResistances.Examples.Pipe

Test of a pipe with multiple segments

### Information

This model demonstrates the use of a pipe model. Both pipe models have the same mass flow rates and temperatures. Otherwise, the `assert` block would terminate the simulation.

The model on the top is connected to the ambient with one heat port, whereas the model at the bottom uses a vector of heat ports. Since they are all connected to the same temperature, they result in the same energy balance for the medium that flows through the pipe.

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

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
replaceable package Medium | Buildings.Media.Water |

### Connectors

Type | Name | Description
--- | --- | ---
replaceable package Medium |

### Modelica definition

model Pipe "Test of a pipe with multiple segments" extends Modelica.Icons.Example; replaceable package Medium = Buildings.Media.Water; Modelica.Blocks.Sources.Ramp P( duration=1, height=2*pip.dp_nominal, offset=101325 - pip.dp_nominal); Buildings.Fluid.Sources.Boundary_pT sou( redeclare package Medium = Medium, use_p_in=true, T=273.15 + 50, nPorts=2); Buildings.Fluid.Sources.Boundary_pT sin( redeclare package Medium = Medium, T=273.15 + 10, nPorts=2, use_p_in=false, p(displayUnit="Pa") = 101325); HeatTransfer.Sources.FixedTemperature TEnv(T=263.15); Buildings.Fluid.FixedResistances.Pipe pip( thicknessIns=0.01, lambdaIns=0.01, m_flow_nominal=10, redeclare package Medium = Medium, length=10, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial); HeatTransfer.Sources.FixedTemperature TEnv1[10](each T=263.15); Buildings.Fluid.FixedResistances.Pipe pip1( thicknessIns=0.01, lambdaIns=0.01, m_flow_nominal=10, redeclare package Medium = Medium, length=10, useMultipleHeatPorts=true, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial); Buildings.Fluid.Sensors.TemperatureTwoPort senTem(redeclare package Medium = Medium, m_flow_nominal=pip.m_flow_nominal) "Temperature sensor"; Buildings.Fluid.Sensors.TemperatureTwoPort senTem1(redeclare package Medium = Medium, m_flow_nominal=pip.m_flow_nominal) "Temperature sensor"; Buildings.Utilities.Diagnostics.AssertEquality assEqu; equation connect(P.y, sou.p_in); connect(sou.ports[1], pip.port_a); connect(TEnv.port, pip.heatPort); connect(sou.ports[2], pip1.port_a); connect(TEnv1.port, pip1.heatPorts); connect(pip.port_b, senTem.port_a); connect(senTem.port_b, sin.ports[1]); connect(pip1.port_b, senTem1.port_a); connect(senTem1.port_b, sin.ports[2]); connect(assEqu.u1, senTem.T); connect(senTem1.T, assEqu.u2); end Pipe;

## Buildings.Fluid.FixedResistances.Examples.SplitterFixedResistanceDpM

Test model for the three way splitter/mixer model

### Information

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

### Modelica definition

model SplitterFixedResistanceDpM "Test model for the three way splitter/mixer model" extends Modelica.Icons.Example; package Medium = Buildings.Media.Air; Buildings.Fluid.FixedResistances.SplitterFixedResistanceDpM spl( m_flow_nominal={1,2,3}, dh={1,2,3}, redeclare package Medium = Medium, dp_nominal(each displayUnit="Pa") = {5,10,15}, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial) "Splitter"; Buildings.Fluid.Sources.Boundary_pT bou1( redeclare package Medium = Medium, T=273.15 + 10, use_p_in=true, nPorts=1); Buildings.Fluid.Sources.Boundary_pT bou2( redeclare package Medium = Medium, T=273.15 + 20, use_p_in=true, nPorts=1); Buildings.Fluid.Sources.Boundary_pT bou3( redeclare package Medium = Medium, T=273.15 + 30, use_p_in=true, nPorts=1); Modelica.Blocks.Sources.Constant P2(k=101325); Modelica.Blocks.Sources.Ramp P1( offset=101320, height=10, duration=0.5); Modelica.Blocks.Sources.Ramp P3( offset=101320, height=10, duration=0.5, startTime=0.5); equation connect(P1.y, bou1.p_in); connect(P2.y, bou2.p_in); connect(bou3.p_in, P3.y); connect(bou1.ports[1], spl.port_1); connect(bou3.ports[1], spl.port_3); connect(spl.port_2, bou2.ports[1]); end SplitterFixedResistanceDpM;