modelNTU_L3

Base heat exchanger wall model with liquid, vapour and 2ph zones

Extends from ClaRa.Basics.Icons.NTU, ClaRa.Basics.Icons.ComplexityLevel (Displays the complexity level inside model icon ).

Information

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
SI.Area	A_heat_m	(A_heat_o - A_heat_i)/log(A_heat_o/A_heat_i)	Mean area of heat transfer (single tube)
SI.Area	A_heat_i	2Modelica.Constants.piradius_ilengthN_t*N_p	Area of heat transfer at inner phase
SI.Area	A_heat_o	2Modelica.Constants.piradius_olengthN_t*N_p	Area of heat transfer at oter phase
Modelica.Units.SI.ThermalResistance	HR_nom	(radius_o - radius_i)/(solid[1].lambda_nominal*A_heat_m)	Nominal conductive heat resistance
SI.Temperature[3]	T_w_i_start	ones(3)*293.15	\|Initialisation\|\|Initial temperature at inner phase
SI.Temperature[3]	T_w_o_start	ones(3)*293.15	\|Initialisation\|\|Initial temperature at outer phase
Real	gain_eff	1	\|Expert Settings\|\|Avoid effectiveness > 1, high gain_eff leads to stricter observation but may cause numeric errors
SI.Time	Tau_stab	0.1	\|Expert Settings\|\|Time constant for state stabilisation
Boolean	showExpertSummary	false	\|Summaries and Visualisation\|\|True,if expert summaries shall be shown
Fundamental Definitions
TILMedia.VLEFluid.Types.BaseVLEFluid	medium_shell	simCenter.fluid1	Medium of shell side
TILMedia.VLEFluid.Types.BaseVLEFluid	medium_tubes	simCenter.fluid1	Medium of tubes side
Boolean	outerPhaseChange	true	True, if phase change may occur at outer side
Geometry
Integer	N_t	1	Number of tubes in one pass
Integer	N_p	1	Number of passes
SI.Length	length		Tube length (for one pass)
SI.Length	radius_i		Inner radius of tube
SI.Length	radius_o		Outer radius of tube
Real	mass_struc	0	Mass of inner structure elements, additional to the tubes itself
Real	CF_geo	1	Correction coefficient due to fins etc.
Initialisation
Integer	initOption	0	Type of initialisation

Connectors

Type	Name	Default	Description
ClaRa.Basics.Interfaces.HeatPort_a[3]	outerPhase		outer side of cylinder
ClaRa.Basics.Interfaces.HeatPort_a[3]	innerPhase		inner side of cylinder

Components

Type	Name	Default	Description
String	complexity (from ComplexityLevel)	"??"
ClaRa.SimCenter	simCenter
SI.Mass	mass		Total mass of HEX
SI.Pressure	p_o		Pressure at outer side
SI.Pressure	p_i		Pressure at inner side
SI.EnthalpyMassSpecific	h_i_inlet		Inlet temperature of inner flow
SI.EnthalpyMassSpecific	h_o_inlet		Inlet temperature of outer flow
SI.MassFlowRate	m_flow_i		Mass flow rate of inner side
SI.MassFlowRate	m_flow_o		Mass flow rate of outer side
ClaRa.Basics.Units.MassFraction[medium_tubes.nc - 1]	xi_i		Mass fraction at outer side
ClaRa.Basics.Units.MassFraction[medium_shell.nc - 1]	xi_o		Mass fraction at outer side
SI.CoefficientOfHeatTransfer[3]	alpha_i		Coefficient of heatTransfer for inner side for regions \|1\|2\|3\|
SI.CoefficientOfHeatTransfer[3]	alpha_o		Coefficient of heatTransfer for outer side for regions \|1\|2\|3\|
SI.AreaFraction	yps_1ph		Area fraction of zone A
SI.AreaFraction	yps_2ph		Area fraction of zone B
Units.HeatCapacityFlowRate[3]	kA		The product U*S for regions \|1\|2\|3\|
SI.HeatFlowRate[3]	Q_flow		Heat flow rate of zones \|1\|2\|3\|
HeatExchangerType	HEXtype
HeatCapacityAveraging	heatCapacityAveraging
Real[3]	cp_error_		Check: Deviation from constant cp in zones \|1\|2\|3\|
Real[3]	effectiveness_act		Actual effectiveness of zones \|1\|2\|3\|
Real[3]	effectiveness		Effectiveness of zones \|1\|2\|3\|
Real[3]	NTU_1		Number of transfer units in zones \|1\|2\|3\|
Real[3]	NTU_ctr		Number of transfer units in zones \|1\|2\|3\| for pure counter flow
Real[3]	C_flow_low		Lower heat capacity flow in zones \|1\|2\|3\|
Real[3]	C_flow_high		Higher heat capacity flow in zones \|1\|2\|3\|
SI.HeatCapacityMassSpecific[3]	cp_o
SI.HeatCapacityMassSpecific[3]	cp_i
Units.ThermalResistance	HR		Conductive heat resistance
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	O1_in
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	O3_out
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	I1_out
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	O2_in
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	I2_out
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	I3_in
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	O2_out
TILMedia.VLEFluid.MixtureCompatible.VLEFluid_ph	I2_in
TILMedia.Solid.Solid[3]	solid
Summary	summary
ClaRa.Basics.ControlVolumes.SolidVolumes.Fundamentals.ICom_NTU_L3	iCom

Name	Description
Material
HeatExchangerType
HeatCapacityAveraging
Summary
ECom

Revisions

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