modelTube
Tube (incl wall) with detailed energy, integrated momentum and mass balance
Extends from SiemensPower.Components.Pipes.TubeWithoutWall (Tube with detailed energy, integrated momentum and mass balance).
Information
This tube model comes with a detailed energy, but integrated momentum and mass balance. See pdf documentation for details of the integration of the hydrodynamic equations. Both heat transfer and friction pressure drop can be selected from a set of correlations.
Model restrictions
- Mass accelaration pressure drop is not considered
- dynamic mass balance has no effect if medium is incompressible
| Author: | Haiko Steuer | SCD |
| Checked by: | ||
| Protection class: | internal |
License, Copyright and Disclaimer
Licensed by Siemens AG under the Siemens Modelica License 2
Copyright 2007-2012 Siemens AG. All rights reserved.
This Modelica package is free software and the use is completely at your own risk; it can be redistributed and/or modified under the terms of the Siemens Modelica License 2. For license conditions (including the disclaimer of warranty) see Siemens Modelica License 2 .
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Real | g (from BaseTube) | Modelica.Constants.g_n | |
| Real | pi (from BaseTube) | Modelica.Constants.pi | |
| Integer | numberOfNodes (from BaseTube) | 2 | Number of nodes for thermal variables |
| SI.Length | diameterInner (from BaseTube) | geoPipe.d_out - 2*geoPipe.s | |
| SI.Length | dz (from BaseTube) | geoPipe.L/numberOfNodes | |
| SI.Volume | V (from BaseTube) | geoPipe.A*geoPipe.L | |
| SI.Area | A (from BaseTube) | geoPipe.A | |
| SI.Volume | VTotal (from BaseTube) | geoPipe.Nt*V | |
| SI.Volume | VCell (from BaseTube) | V/numberOfNodes | |
| Real | sinphi (from BaseTube) | geoPipe.H/geoPipe.L | |
| Initialization | |||
| Modelica.SIunits.MassFlowRate | m_flow_start (from PartialTwoPortTransport) | 1 | Guess value for mass flow rate |
| Medium.AbsolutePressure | pIn_start (from PartialTwoPortTransport) | Medium.reference_p | Start value of inlet pressure |
| Medium.AbsolutePressure | pOut_start (from PartialTwoPortTransport) | Medium.reference_p | Start value of outlet pressure |
| Boolean | useTemperatureStartValue (from PartialTwoPortTransport) | false | Use T_start if true, otherwise h_start |
| Medium.SpecificEnthalpy | hIn_start (from PartialTwoPortTransport) | if useTemperatureStartValue then Medium.specificEnthalpy_pTX(pIn_start, TIn_start, XIn_start) else Medium.h_default | Start value of specific enthalpy |
| Medium.SpecificEnthalpy | hOut_start (from PartialTwoPortTransport) | if useTemperatureStartValue then Medium.specificEnthalpy_pTX(pOut_start, TOut_start, XOut_start) else Medium.h_default | Start value of specific outlet enthalpy |
| Medium.Temperature | TIn_start (from PartialTwoPortTransport) | if useTemperatureStartValue then Medium.reference_T else Medium.temperature_phX(pIn_start, hIn_start, XIn_start) | Start value of temperature |
| Medium.Temperature | TOut_start (from PartialTwoPortTransport) | if useTemperatureStartValue then Medium.reference_T else Medium.temperature_phX(pOut_start, hOut_start, XOut_start) | Start value of outlet temperature |
| Medium.MassFraction[Medium.nX] | XIn_start (from PartialTwoPortTransport) | Medium.reference_X | Start value of mass fractions m_i/m |
| Medium.MassFraction[Medium.nX] | XOut_start (from PartialTwoPortTransport) | Medium.reference_X | Start value of mass fractions m_i/m |
| Boolean | initializeInletPressure (from BaseTube) | true | add steady state equation for pressure |
| Boolean | initializeSteadyStateEnthalpies (from BaseTube) | true | lets initialize der(h)=0 |
| Boolean | initializeSteadyStateInletEnthalpy (from BaseTube) | true | steady state initial condition for input enthalpy |
| SI.CoefficientOfHeatTransfer | alpha_start | 10000 | Heat transfer coefficient (not too small for valid wall temperature) |
| Geometry and correlations | |||
| SiemensPower.Utilities.Structures.PipeGeo | geoPipe (from BaseTube) | Geometry of tube | |
| Advanced › Initialization | |||
| Medium.SpecificEnthalpy[numberOfNodes] | h_start (from BaseTube) | hIn_start*ones(numberOfNodes) + (hOut_start - hIn_start)*equalCellDistribution | guess values for initial enthalpy vector |
| SI.HeatFlowRate[numberOfNodes] | Q_flow_start (from BaseTube) | (hOut_start - hIn_start)*m_flow_start/(geoPipe.Nt*numberOfNodes)*ones(numberOfNodes) | Detailed start values for heat flow |
| Advanced › Inner heat transfer | |||
| SI.Area | heatedArea (from BaseTube) | geoPipe.Nt*geoPipe.L*Modelica.Constants.pi*diameterInner | Total Area for heat transfer |
| Wall | |||
| Integer | numberOfWallLayers | 3 | Number of wall layers |
| SiemensPower.Utilities.Structures.PropertiesMetal | metal | Wall metal properties | |
| Initialization › Wall | |||
| Medium.Temperature[numberOfNodes] | TWall_start | T_start + q_start/alpha_start*ones(numberOfNodes) | start values for wall temperatures |
| Advanced › Branch geometry (for stress calculation) | |||
| SI.Length | diameterBranch | geoPipe.d_out - 2*geoPipe.s | Average aperture of branch |
| SI.Length | wallThicknessBranch | geoPipe.s | Wall thickness of branch |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Fluid.Interfaces.FluidPort_a | portIn (from PartialTwoPortTransport) | Inlet port | |
| Modelica.Fluid.Interfaces.FluidPort_b | portOut (from PartialTwoPortTransport) | Outlet port | |
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a[numberOfNodes] | heatPort | Outer wall heat port |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Medium.SpecificEnthalpy | hIn (from PartialTwoPortTransport) | actual state at portIn | |
| Medium.SpecificEnthalpy | hOut (from PartialTwoPortTransport) | actual state at portOut | |
| SI.Pressure | dp (from PartialTwoPortTransport) | ||
| Medium.BaseProperties[numberOfNodes] | fluid (from BaseTube) | ||
| Medium.MassFlowRate[numberOfNodes] | m_flows (from BaseTube) | ||
| Medium.Density | d_av (from BaseTube) | ||
| SI.SpecificVolume | vol_av (from BaseTube) | ||
| SI.Pressure | dpfric (from BaseTube) | ||
| SI.Pressure | dphyd (from BaseTube) | ||
| Medium.AbsolutePressure | p (from TubeWithoutWall) | pressure | |
| SiemensPower.Components.SolidComponents.Wall | wall | Metal wall of the tube | |
| SiemensPower.Interfaces.portHeat | heatport | inner wall (masked) heat port | |
| SI.CoefficientOfHeatTransfer[numberOfNodes] | alpha |
Contents
| Name | Description |
|---|---|
| heattransfer |
Revisions
- December 2006, added by Haiko Steuer