modelPipe
Pipe with 1D discretisation along flow direction
Extends from BuildingSystems.Fluid.Interfaces.LumpedVolumeDeclarations, BuildingSystems.Fluid.Interfaces.PartialTwoPortInterface, BuildingSystems.Fluid.Interfaces.TwoPortFlowResistanceParameters.
Information
Model of a straight pipe with flow resistance and optional heat storage.
This model can be used for modeling the heat exchange between the pipe and environment.
The model consists of a flow resistance
BuildingSystems.Fluid.FixedResistances.FixedResistanceDpM
and nNodes mixing volumes
BuildingSystems.Fluid.MixingVolumes.MixingVolume.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Integer | nNodes | 1 | Number of volume segments |
| Boolean | useMultipleHeatPorts | false | = true to use one heat port for each segment of the pipe, false to use a single heat port for the entire pipe |
| Geometry | |||
| Modelica.Units.SI.Length | length | Length of the pipe | |
| Modelica.Units.SI.Length | diameter | sqrt(4*m_flow_nominal/rho_default/v_nominal/Modelica.Constants.pi) | Pipe diameter (without insulation) |
| Modelica.Units.SI.Length | thicknessIns | Thickness of insulation | |
| Material | |||
| Modelica.Units.SI.ThermalConductivity | lambdaIns | Heat conductivity of insulation | |
| Flow resistance | |||
| Modelica.Units.SI.ReynoldsNumber | ReC | 4000 | Reynolds number where transition to turbulent starts |
| Advanced | |||
| Boolean | useExternalHeatSource | false | = true to transfer the volume temperature to the outer interface (heatPort) |
| Heat transfer | |||
| Modelica.Units.SI.SurfaceCoefficientOfHeatTransfer | alpha_in | 1000.0 | Heat transfer coefficient pipe inside |
| Modelica.Units.SI.SurfaceCoefficientOfHeatTransfer | alpha_out | 3.0 | Heat transfer coefficient pipe outside |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| BuildingSystems.Fluid.FixedResistances.HydraulicDiameter | res | Flow resistance | |
| BuildingSystems.Fluid.MixingVolumes.MixingVolume[nNodes] | vol | Volume for pipe fluid | |
| Modelica.Thermal.HeatTransfer.Components.ThermalConductor[nNodes] | conPipWal | Thermal heat transfer through pipe wall | |
| Modelica.Thermal.HeatTransfer.Components.ThermalCollector | colAllToOne | Connector to assign multiple heat ports to one heat port | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | heatPort | Single heat port that connects to outside of pipe wall (default, enabled when useMultipleHeatPorts=false) | |
| Modelica.Fluid.Interfaces.HeatPorts_a[nNodes] | heatPorts | Multiple heat ports that connect to outside of pipe wall (enabled if useMultipleHeatPorts=true) | |
| Modelica.Thermal.HeatTransfer.Components.ThermalCollector[nNodes] | thermalCollector1 |
Revisions
-
May 13, 2021, by Christoph Nytsch-Geusen:
Thermal heat transfer calculation through pipe walls extendend with internal and external convective heat transfer coefficients. -
June 1, 2015, by Christoph Nytsch-Geusen:
Adaptation from the Builings to the BuildingSystms library. -
October 8, 2013, by Michael Wetter:
Removed parametershow_V_flow. -
September 13, 2013 by Michael Wetter:
Replacednominalwithdefaultvalues as they are computed using the default Medium values. -
February 15, 2012 by Michael Wetter:
Changed base class from which the model extends. Propagated parameters of volume to the top if this model. -
February 12, 2012 by Wangda Zuo:
First implementation.