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Buildings.Fluid.HeatExchangers.RadiantSlabs.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.HeatExchangers.RadiantSlabs.

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

Package Content

Name Description
Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitEpsilonNTU SingleCircuitMultipleCircuitEpsilonNTU Model that tests the radiant slab with multiple parallel circuits and epsilon-NTU configuration
Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitFiniteDifference SingleCircuitMultipleCircuitFiniteDifference Model that tests the radiant slab with multiple parallel circuits
Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseEpsilonNTU StepResponseEpsilonNTU Model that tests the radiant slab with epsilon-NTU configuration
Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseFiniteDifference StepResponseFiniteDifference Model that tests the radiant slab

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitEpsilonNTU Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitEpsilonNTU

Model that tests the radiant slab with multiple parallel circuits and epsilon-NTU configuration

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitEpsilonNTU

Information

This model is identical to Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuit except that the number of segments in the slab is set to 1 and the heat transfer between the fluid and the slab is computed using an epsilon-NTU model.

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

Parameters

TypeNameDefaultDescription
MassFlowRatem_flow_nominal0.167Nominal mass flow rate for each circuit [kg/s]
AreaA10Heat transfer area for each circuit [m2]
Genericlayers Material layers from surface a to b (8cm concrete, 5 cm insulation, 20 cm reinforced concrete)
PEX_RADTESTpipe Pipe material
IntegernCir2Number of parallel circuits for slab 3

Modelica definition

model SingleCircuitMultipleCircuitEpsilonNTU "Model that tests the radiant slab with multiple parallel circuits and epsilon-NTU configuration" extends Modelica.Icons.Example; package Medium = Buildings.Media.Water; Sources.Boundary_ph sin(redeclare package Medium = Medium, nPorts=3, p(displayUnit="Pa") = 300000) "Sink"; Modelica.Blocks.Sources.Pulse pulse( startTime=0, amplitude=50*400, offset=300000 - 50*200, width=50, period=86400/2); Buildings.Fluid.HeatExchangers.RadiantSlabs.SingleCircuitSlab sla1( m_flow_nominal=m_flow_nominal, redeclare package Medium = Medium, layers=layers, iLayPip=1, pipe=pipe, sysTyp=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType.Floor, disPip=0.2, A=A, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, from_dp=true) "Slabe with embedded pipes"; parameter Modelica.SIunits.MassFlowRate m_flow_nominal= 0.167 "Nominal mass flow rate for each circuit"; Modelica.Thermal.HeatTransfer.Sources.FixedTemperature TAbo(T=293.15) "Air temperature above the slab"; Modelica.Thermal.HeatTransfer.Sources.FixedTemperature TBel(T=293.15) "Radiant temperature below the slab"; Modelica.Thermal.HeatTransfer.Components.ThermalConductor conAbo1(G=20*A) "Combined convection and radiation resistance above the slab"; parameter Modelica.SIunits.Area A=10 "Heat transfer area for each circuit"; Modelica.Thermal.HeatTransfer.Components.ThermalConductor conBel1(G=20*A) "Combined convection and radiation resistance below the slab"; parameter HeatTransfer.Data.OpaqueConstructions.Generic layers(nLay=3, material={ Buildings.HeatTransfer.Data.Solids.Generic( x=0.08, k=1.13, c=1000, d=1400, nSta=5),Buildings.HeatTransfer.Data.Solids.Generic( x=0.05, k=0.04, c=1400, d=10),Buildings.HeatTransfer.Data.Solids.Generic( x=0.2, k=1.8, c=1100, d=2400)}) "Material layers from surface a to b (8cm concrete, 5 cm insulation, 20 cm reinforced concrete)"; parameter Data.Pipes.PEX_RADTEST pipe "Pipe material"; Modelica.Thermal.HeatTransfer.Components.ThermalConductor conAbo2(G=20*A) "Combined convection and radiation resistance above the slab"; Buildings.Fluid.HeatExchangers.RadiantSlabs.SingleCircuitSlab sla2( m_flow_nominal=m_flow_nominal, redeclare package Medium = Medium, layers=layers, iLayPip=1, pipe=pipe, sysTyp=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType.Floor, disPip=0.2, A=A, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, from_dp=true) "Slabe with embedded pipes"; Modelica.Thermal.HeatTransfer.Components.ThermalConductor conBel2(G=20*A) "Combined convection and radiation resistance below the slab"; Modelica.Thermal.HeatTransfer.Components.ThermalConductor conBel3(G=nCir*20*A) "Combined convection and radiation resistance below the slab"; ParallelCircuitsSlab sla3( redeclare package Medium = Medium, layers=layers, iLayPip=1, pipe=pipe, sysTyp=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType.Floor, disPip=0.2, nCir=nCir, A=nCir*A, m_flow_nominal=nCir*m_flow_nominal, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, from_dp=true) "Slabe with embedded pipes"; Modelica.Thermal.HeatTransfer.Components.ThermalConductor conAbo3(G=nCir*20*A) "Combined convection and radiation resistance above the slab"; Sensors.TemperatureTwoPort senTem1(redeclare package Medium = Medium, m_flow_nominal=m_flow_nominal/2) "Temperature sensor"; Sensors.TemperatureTwoPort senTem2(redeclare package Medium = Medium, m_flow_nominal=m_flow_nominal/2) "Temperature sensor"; Sensors.TemperatureTwoPort senTem3(redeclare package Medium = Medium, m_flow_nominal=nCir*m_flow_nominal) "Temperature sensor"; Sources.Boundary_pT sou( redeclare package Medium = Medium, nPorts=3, use_p_in=true, T=313.15) "Source"; parameter Integer nCir=2 "Number of parallel circuits for slab 3"; equation connect(TBel.port, conBel1.port_a); connect(conBel1.port_b, sla1.surf_b); connect(sla1.surf_a, conAbo1.port_a); connect(TAbo.port, conAbo1.port_b); connect(TAbo.port, conAbo2.port_b); connect(conAbo2.port_a, sla2.surf_a); connect(TBel.port, conBel2.port_a); connect(TBel.port, conBel3.port_a); connect(TAbo.port, conAbo3.port_b); connect(conAbo3.port_a, sla3.surf_a); connect(conBel3.port_b, sla3.surf_b); connect(sla1.port_b, senTem1.port_a); connect(sla2.port_b, senTem2.port_a); connect(sla3.port_b, senTem3.port_a); connect(senTem1.port_b, sin.ports[1]); connect(senTem2.port_b, sin.ports[2]); connect(senTem3.port_b, sin.ports[3]); connect(conBel2.port_b, sla2.surf_b); connect(pulse.y, sou.p_in); connect(sou.ports[1], sla1.port_a); connect(sou.ports[2], sla2.port_a); connect(sou.ports[3], sla3.port_a); end SingleCircuitMultipleCircuitEpsilonNTU;

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitFiniteDifference Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitFiniteDifference

Model that tests the radiant slab with multiple parallel circuits

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitFiniteDifference

Information

This example compares the results of two models of a single circuit that are arranged in parallel, versus a model that directly implements two parallel circuits. Both configurations have the same mass flow rate and temperatures. For simplicity, a combined convective and radiative resistance which is independent of the temperature difference has been used. The model is exposed to a step change in pressure, which causes forward and reverse flow.

Extends from Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitEpsilonNTU (Model that tests the radiant slab with multiple parallel circuits and epsilon-NTU configuration).

Parameters

TypeNameDefaultDescription
MassFlowRatem_flow_nominal0.167Nominal mass flow rate for each circuit [kg/s]
AreaA10Heat transfer area for each circuit [m2]
Genericlayers Material layers from surface a to b (8cm concrete, 5 cm insulation, 20 cm reinforced concrete)
PEX_RADTESTpipe Pipe material
IntegernCir2Number of parallel circuits for slab 3

Modelica definition

model SingleCircuitMultipleCircuitFiniteDifference "Model that tests the radiant slab with multiple parallel circuits" extends Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.SingleCircuitMultipleCircuitEpsilonNTU ( sla1(heatTransfer=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.HeatTransfer.FiniteDifference), sla2(heatTransfer=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.HeatTransfer.FiniteDifference), sla3(heatTransfer=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.HeatTransfer.FiniteDifference)); end SingleCircuitMultipleCircuitFiniteDifference;

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseEpsilonNTU Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseEpsilonNTU

Model that tests the radiant slab with epsilon-NTU configuration

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseEpsilonNTU

Information

This model is identical to Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponse except that the number of segments in the slab is set to 1 and the heat transfer between the fluid and the slab is computed using an epsilon-NTU model.

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

Parameters

TypeNameDefaultDescription
MassFlowRatem_flow_nominal0.167Nominal mass flow rate [kg/s]
AreaA10Heat transfer area [m2]
Genericlayers Material layers from surface a to b (8cm concrete, 5 cm insulation, 20 cm reinforced concrete)
PEX_RADTESTpipe Pipe material

Modelica definition

model StepResponseEpsilonNTU "Model that tests the radiant slab with epsilon-NTU configuration" extends Modelica.Icons.Example; package Medium = Buildings.Media.Water; Sources.Boundary_ph sin(redeclare package Medium = Medium, nPorts=1) "Sink"; Sources.MassFlowSource_T sou( redeclare package Medium = Medium, use_m_flow_in=true, T=298.15, nPorts=1) "Source"; Modelica.Blocks.Sources.Pulse pulse( period=86400, startTime=0, amplitude=-m_flow_nominal, offset=m_flow_nominal); Buildings.Fluid.HeatExchangers.RadiantSlabs.SingleCircuitSlab sla( m_flow_nominal=m_flow_nominal, redeclare package Medium = Medium, layers=layers, iLayPip=1, pipe=pipe, sysTyp=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.SystemType.Floor, disPip=0.2, A=A, energyDynamics=Modelica.Fluid.Types.Dynamics.FixedInitial, heatTransfer=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.HeatTransfer.FiniteDifference) "Slabe with embedded pipes"; parameter Modelica.SIunits.MassFlowRate m_flow_nominal= 0.167 "Nominal mass flow rate"; Modelica.Thermal.HeatTransfer.Sources.FixedTemperature TAirAbo(T=293.15) "Air temperature above the slab"; Modelica.Thermal.HeatTransfer.Sources.FixedTemperature TRadAbo(T=293.15) "Radiant temperature above the slab"; Modelica.Thermal.HeatTransfer.Sources.FixedTemperature TAirBel(T=293.15) "Air temperature below the slab"; Modelica.Thermal.HeatTransfer.Sources.FixedTemperature TRadBel(T=293.15) "Radiant temperature below the slab"; HeatTransfer.Convection.Interior conAbo( A=A, conMod=Buildings.HeatTransfer.Types.InteriorConvection.Temperature, til=Buildings.Types.Tilt.Floor) "Convective heat transfer above the slab"; parameter Modelica.SIunits.Area A=10 "Heat transfer area"; HeatTransfer.Convection.Interior conBel( A=A, conMod=Buildings.HeatTransfer.Types.InteriorConvection.Temperature, til=Buildings.Types.Tilt.Ceiling) "Convective heat transfer below the slab"; Modelica.Thermal.HeatTransfer.Components.BodyRadiation hRadAbo(Gr=A/(1/0.7 + 1 /0.7 - 1)) "Radiative heat transfer above the slab"; Modelica.Thermal.HeatTransfer.Components.BodyRadiation hRadBel(Gr=A/(1/0.7 + 1 /0.7 - 1)) "Radiative heat transfer below the slab"; parameter HeatTransfer.Data.OpaqueConstructions.Generic layers(nLay=3, material={ Buildings.HeatTransfer.Data.Solids.Generic( x=0.08, k=1.13, c=1000, d=1400, nSta=5),Buildings.HeatTransfer.Data.Solids.Generic( x=0.05, k=0.04, c=1400, d=10),Buildings.HeatTransfer.Data.Solids.Generic( x=0.2, k=1.8, c=1100, d=2400)}) "Material layers from surface a to b (8cm concrete, 5 cm insulation, 20 cm reinforced concrete)"; parameter Data.Pipes.PEX_RADTEST pipe "Pipe material"; Sensors.TemperatureTwoPort TOut(redeclare package Medium = Medium, m_flow_nominal=m_flow_nominal) "Outlet temperature of the slab"; equation connect(pulse.y, sou.m_flow_in); connect(sou.ports[1], sla.port_a); connect(TAirAbo.port, conAbo.fluid); connect(TRadAbo.port, hRadAbo.port_a); connect(TAirBel.port, conBel.fluid); connect(TRadBel.port, hRadBel.port_a); connect(conAbo.solid, sla.surf_a); connect(hRadAbo.port_b, sla.surf_a); connect(conBel.solid, sla.surf_b); connect(hRadBel.port_b, sla.surf_b); connect(sla.port_b, TOut.port_a); connect(TOut.port_b, sin.ports[1]); end StepResponseEpsilonNTU;

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseFiniteDifference Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseFiniteDifference

Model that tests the radiant slab

Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseFiniteDifference

Information

This example models the step response of a radiant slab.

Extends from Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseEpsilonNTU (Model that tests the radiant slab with epsilon-NTU configuration).

Parameters

TypeNameDefaultDescription
MassFlowRatem_flow_nominal0.167Nominal mass flow rate [kg/s]
AreaA10Heat transfer area [m2]
Genericlayers Material layers from surface a to b (8cm concrete, 5 cm insulation, 20 cm reinforced concrete)
PEX_RADTESTpipe Pipe material

Modelica definition

model StepResponseFiniteDifference "Model that tests the radiant slab" extends Buildings.Fluid.HeatExchangers.RadiantSlabs.Examples.StepResponseEpsilonNTU ( sla(heatTransfer=Buildings.Fluid.HeatExchangers.RadiantSlabs.Types.HeatTransfer.FiniteDifference)); end StepResponseFiniteDifference;

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