modelWalllayer

Cylindrical metal tube (single layer)

Information

This is the model of a cylindrical tube layer of solid material.

The heat capacity (which is lumped at the center of the tube thickness) is accounted for, as well as the thermal resistance due to the finite heat conduction coefficient. Longitudinal heat conduction is neglected.

Modelling options

The following options are available to specify the valve flow coefficient in fully open conditions:

considerConductivity = false: the thermal resistance of the tube wall is neglected.
considerConductivity = true: the thermal resistance of the tube wall is accounted for.

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	pi	Modelica.Constants.pi
Integer	numberOfNodes	2	Number of nodes
Boolean	assumePlainHeatTransfer	false	no logarithmic correction
Integer	numberOfParallelTubes	1	Number of parallel tubes
SI.Length	length	1	Tube length
SI.Length	diameterInner	0.08	Internal diameter (single tube)
SI.Length	wallThickness	0.008	Wall thickness
Boolean	useDynamicEquations	true	switch off for steady-state simulations
Boolean	considerConductivity	true	Wall conduction resistance accounted for
Boolean	considerAxialHeatTransfer	false	With heat transfer in the wall parallel to the flow direction
Material
SiemensPower.Utilities.Structures.PropertiesMetal	metal		Wall metal properties
Initialization
String	initOpt	"steadyState"	Initialisation option
SI.Temperature[numberOfNodes]	T_start		Temperature start values

Connectors

Type	Name	Default	Description
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a	port_ext		Outer heat port
Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_b	port_int		Inner heat port

Components

Type	Name	Description
SI.Area	Am	Area of the metal tube cross-section
SI.Temperature[numberOfNodes]	T	Node temperatures
SI.Length	rint
SI.Length	rext
SI.Mass	Tube_mass
SI.HeatCapacity	HeatCap	HeatCapacity of a Tube part

Revisions

December 2006, adapted to SiemensPower by Haiko Steuer
30 May 2005 by Francesco Casella:
Initialisation support added.
1 Oct 2003 by Francesco Casella:
First release.