modelConvection_finnedTubes_L2

Shell Geo || L2 || Convection Finned Tube Bank VDI WA

Extends from ClaRa.Basics.ControlVolumes.Fundamentals.HeatTransport.Gas_HT.Convection.HeatTransfer_L2, ClaRa.Basics.ControlVolumes.Fundamentals.HeatTransport.HeatTransferBaseGas_only (Partial heat transfer model for only Gas-type HT models).

Information

Model description: A correlation for convective heat transfer inside finned tube banks

FEATURES

This model uses TILMedia
Aligned and staggered tubes supported
Supports circular or quadratic fins only
Needs geometry model for tube banks
Equations according to: VDI-Wärmeatlas: 10.bearbeitete und erweiterte Auflage, 2006, chapter Mb1-4 and H. Effenberger: Dampferzeugung, chapter 9.3.5

For detailed model documentation please consult the html-documentation shipped with ClaRa.

Authorship and Copyright Statement for original (initial) Contribution

Author:

References:

For references please consult the html-documentation shipped with ClaRa.

Remarks:

This component was developed by ClaRa development team under the 3-clause BSD License.

Acknowledgements:

ClaRa originated from the collaborative research projects DYNCAP and DYNSTART. Both research projects were supported by the German Federal Ministry for Economic Affairs and Energy (FKZ 03ET2009 and FKZ 03ET7060).

CLA:

The author(s) have agreed to ClaRa CLA, version 1.0. See https://claralib.com/pdf/CLA.pdf

By agreeing to ClaRa CLA, version 1.0 the author has granted the ClaRa development team a permanent right to use and modify his initial contribution as well as to publish it or its modified versions under the 3-clause BSD License.

The ClaRa development team consists of the following partners:

TLK-Thermo GmbH (Braunschweig, Germany)

XRG Simulation GmbH (Hamburg, Germany).

Parameters

Type	Name	Default	Description
String	gas (from HeatTransferBaseGas)	"true"
Boolean	useHomotopy (from HeatTransfer_L2)
Integer	HT_type	1
Integer	heatSurfaceAlloc	2	To be considered heat transfer area
Real	N_f	geo.N_tubesgeo.N_passesgeo.length_tubes/t_f	Number of fins
Real	N_tubes_p	geo.N_tubes_parallel	Number of parallel tubes
ClaRa.Basics.Units.Area	A_finned	A_fN_f + A_ts(N_f + 1)	Finned surface (overall)
ClaRa.Basics.Units.Area	A_tubes	geo.A_heat[2]	Tube surface (overall, as it were without fins)
Heat Transfer
String	temperatureDifference (from HeatTransfer_L2)	"Logarithmic mean - smoothed"	Temperature Difference
Fin geometry
ClaRa.Basics.Units.Length	h_f	0.04	Fin heigth
ClaRa.Basics.Units.Length	s_f	0.002	Fin thickness
ClaRa.Basics.Units.Length	t_f	0.01	Fin spacing
String	finGeometryType	"Circular fins"	Fin geometry

Connectors

Type	Name	Default	Description
ClaRa.Basics.Interfaces.HeatPort_a	heat (from HeatTransfer_L2)

Components

Type	Name	Default	Description
ClaRa.Basics.Records.IComGas_L2	iCom (from HeatTransfer_L2)
Real	CF_fouling (from HeatTransfer_L2)	0.8	Scaling factor accounting for the fouling of the wall
Units.Temperature	Delta_T_wi (from HeatTransfer_L2)		Temperature difference between wall and fluid inlet temperature
Units.Temperature	Delta_T_wo (from HeatTransfer_L2)		Temperature difference between wall and fluid outlet temperature
Units.Temperature	Delta_T_mean (from HeatTransfer_L2)		Mean temperature
Units.Temperature	Delta_T_U (from HeatTransfer_L2)		Upper temperature difference
Units.Temperature	Delta_T_L (from HeatTransfer_L2)		Lower temperature difference
ClaRa.Basics.Units.CoefficientOfHeatTransfer	alpha
ClaRa.Basics.Units.Velocity	w_0		Flue gas velocity at narrowed cross section
ClaRa.Basics.Units.Velocity	w		Flue gas velocity at free cross section
ClaRa.Basics.Units.Temperature	T_f		Fin temperature
Real	Nu		Nusselt number
Real	Re		Reynolds number
ClaRa.Basics.Units.ThermalResistance	HR		Convective heat resistance
ClaRa.Basics.Units.ThermalResistance	HR_nom		Nominal convective heat resistance

Name	Description
solidType

Revisions

For revisions please consult the html-documentation shipped with ClaRa.