modelRegenerativeAirPreheaterPrimaryAndSecondaryAir_L4

Model for a regenerative air preheater with primary and secondary air
Diagram of RegenerativeAirPreheaterPrimaryAndSecondaryAir_L4

Extends from ClaRa.Basics.Icons.AirPreheaterQuart.

Information

Model description: A model for regenerative air preheaters

FEATURES

  • This model uses TILMedia
  • Component is build up as counter current heat exchanger with simplified heat transfer correlations
  • Heat transfer equations according to: H. Effenberger: Dampferzeugung, chapter 9.34
  • Two air mass flows (primary and secondary) are considered
  • Due to the modeling as counter current heat exchanger, the flue gas mass flow is split up by imaginary flue gas areas (normally one single cross sectional area)
  • Air leakage is considered from primary to secondary air on the hot side and from secondary air to flue gas on the cold side with constant values

 

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

 


Authorship and Copyright Statement for original (initial) Contribution

Author:

DYNCAP/DYNSTART development team, Copyright © 2011-2024.

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

TypeNameDefaultDescription
ClaRa.Basics.Units.MassFlowRatem_flow_primaryAir_nom250|Physical Effects|Nominal values|Nominal value of primary fresh air mass flow rate
ClaRa.Basics.Units.MassFlowRatem_flow_secondaryAir_nom250|Physical Effects|Nominal values|Nominal value of secondary fresh air mass flow rate
ClaRa.Basics.Units.MassFlowRatem_flow_flueGas_nom300|Physical Effects|Nominal values|Nominal value of flue gas mass flow rate
ClaRa.Basics.Units.Pressurep_primaryAir_nom1.0e5|Physical Effects|Nominal values|Nominal value of primary fresh air pressure loss
ClaRa.Basics.Units.Pressurep_secondaryAir_nom1.0e5|Physical Effects|Nominal values|Nominal value of secondary fresh air pressure loss
ClaRa.Basics.Units.Pressurep_flueGas_nom1.0e5|Physical Effects|Nominal values|Nominal value of flue gas pressure loss
ClaRa.Basics.Units.PressureDelta_p_primaryAir_nom1.0e4|Physical Effects|Nominal values|Nominal value of primary fresh air pressure loss
ClaRa.Basics.Units.PressureDelta_p_secondaryAir_nom1.0e4|Physical Effects|Nominal values|Nominal value of secondary fresh air pressure loss
ClaRa.Basics.Units.PressureDelta_p_flueGas_nom1.0e4|Physical Effects|Nominal values|Nominal value of flue gas pressure loss
Basics.Units.MassFraction[medium.nc - 1]xi_nom_primaryAirmedium.xi_default|Physical Effects|Nominal values|Nominal composition of primary fresh air
Basics.Units.MassFraction[medium.nc - 1]xi_nom_secondaryAirmedium.xi_default|Physical Effects|Nominal values|Nominal composition of primary fresh air
Basics.Units.MassFraction[medium.nc - 1]xi_nom_flueGasmedium.xi_default|Physical Effects|Nominal values|Nominal composition of flue gas
BooleanfrictionAtPrimaryAirInletfalse|Physical Effects|Pressure Loss|True if pressure loss between first primary air cell and inlet shall be considered
BooleanfrictionAtPrimaryAirOutletfalse|Physical Effects|Pressure Loss|True if pressure loss between last primary air cell and outlet shall be considered
BooleanfrictionAtSecondaryAirInletfalse|Physical Effects|Pressure Loss|True if pressure loss between first secondary air cell and inlet shall be considered
BooleanfrictionAtSecondaryAirOutletfalse|Physical Effects|Pressure Loss|True if pressure loss between last secondary air cell and outlet shall be considered
BooleanfrictionAtFlueGasInletfalse|Physical Effects|Pressure Loss|True if pressure loss between first flue gas cell and inlet shall be considered
BooleanfrictionAtFlueGasOutletfalse|Physical Effects|Pressure Loss|True if pressure loss between last flue gas cell and outlet shall be considered
ClaRa.Basics.Units.AreaA_heat_primaryvolume_primary_eff*COverall primary heat transfer area
ClaRa.Basics.Units.AreaA_heat_secondaryvolume_secondary_eff*COverall secondary heat transfer area
ClaRa.Basics.Units.Lengthb(diameter_reg - diameter_hub)/2Length of storage material plates
ClaRa.Basics.Units.AreaA_platesN_sp*s_sp*2*bCross sectional area in flow direction blocked by plates
Realf_platesA_plates/(A_cross - A_hub)Factor of cross sectional area in flow direction blocked by plates
ClaRa.Basics.Units.AreaA_primaryAir_freeA_primaryAir*(1 - f_plates)Cross sectional area of primary air flow
ClaRa.Basics.Units.AreaA_secondaryAir_freeA_secondaryAir*(1 - f_plates)Cross sectional area of secondary air flow
ClaRa.Basics.Units.AreaA_flueGas_primary_freeA_flueGas_primary*(1 - f_plates)Cross sectional area of primary flue gas flow
ClaRa.Basics.Units.AreaA_flueGas_secondary_freeA_flueGas_secondary*(1 - f_plates)Cross sectional area of secondary flue gas flow
ClaRa.Basics.Units.Volumevolume_flueGas_primaryA_flueGas_primary_free*height_regFlue gas volume (primary heat exchange)
ClaRa.Basics.Units.Volumevolume_flueGas_secondaryA_flueGas_primary_free*height_regFlue gas volume (secondary heat exchange)
ClaRa.Basics.Units.Volumevolume_primaryAirA_primaryAir_free*height_regPrimary air volume
ClaRa.Basics.Units.Volumevolume_secondaryAirA_secondaryAir_free*height_regSecondary air volume
ClaRa.Basics.Units.Volumevolume_primary_eff(A_primaryAir + A_flueGas_primary)*height_regEffective regenerator volume (primary part)
ClaRa.Basics.Units.Volumevolume_secondary_eff(A_secondaryAir + A_flueGas_secondary)*height_regEffective regenerator volume (secondary part)
ClaRa.Basics.Units.Volumevolume_st_primary(A_cross - A_hub - A_secondaryAir - A_flueGas_secondary)*(f_plates)*height_regVolume of solid regenerator storage material (primary part)
ClaRa.Basics.Units.Volumevolume_st_secondary(A_cross - A_hub - A_primaryAir - A_flueGas_primary)*(f_plates)*height_regVolume of solid regenerator storage material (secondary part)
ClaRa.Basics.Units.Massmass_primaryif calculate_mass then volume_st_primary*solid.d else mass_fixed*volume_st_primary/(volume_st_primary + volume_st_secondary)Mass of regenerator storage material (primary part)
ClaRa.Basics.Units.Massmass_secondaryif calculate_mass then volume_st_secondary*solid.d else mass_fixed*volume_st_secondary/(volume_st_primary + volume_st_secondary)Mass of regenerator storage material (secondary part)
ClaRa.Basics.Units.Lengthd_gl4*(A_cross - A_hub - A_plates - A_covered)/(2*N_sp*b)Equivalent diameter
RealflueGas_split_ratioA_flueGas_primary_free/(A_flueGas_secondary_free + A_flueGas_primary_free)
Geometry
Booleancalculate_masstrueTrue, if mass is calculated with nominal material density
ClaRa.Basics.Units.Massmass_fixed100000Fixed overall storage mass
ClaRa.Basics.Units.Lengthdiameter_reg8Regenerator diameter
ClaRa.Basics.Units.Lengthdiameter_hub0.5Hub diameter
ClaRa.Basics.Units.Lengthheight_reg2Regenerator height
RealN_sp3500Number of storage plates
ClaRa.Basics.Units.Lengths_sp0.6e-3Thickness of storage plates
RealC440Heating surface per volume (m^2/m^3)
ClaRa.Basics.Units.AreaA_covered0.1*(A_cross - A_hub)Covered regenerator cross section
ClaRa.Basics.Units.AreaA_flueGas_primary0.2*(A_cross - A_hub)Cross section hit by flue gas (which transfers heat to primary air)
ClaRa.Basics.Units.AreaA_flueGas_secondary0.25*(A_cross - A_hub)Cross section hit by flue gas (which transfers heat to secondary air)
ClaRa.Basics.Units.AreaA_primaryAir0.2*(A_cross - A_hub)Cross section hit by primary air
ClaRa.Basics.Units.AreaA_secondaryAir0.25*(A_cross - A_hub)Cross section hit by secondary air
ClaRa.Basics.Units.AreaA_crossModelica.Constants.pi/4*diameter_reg^2Overall regenerator cross section
General › Geometry
ClaRa.Basics.Units.AreaA_hubModelica.Constants.pi/4*diameter_hub^2Hub cross sectionHub cross section
Leakage
Realleakage_primaryAir0.1Ratio of mass leakage from hot primary air to hot secondary air
Realleakage_secondaryAir0.05Ratio of mass leakage from cold secondary air to cold flue gas
Discretisation
IntegerN_cv3Number of finite control volumes
Initialisation
BooleanuseHomotopysimCenter.useHomotopyTrue, if homotopy method is used during initialisation
IntegerinitOptionCells0Type of gas cell initialisation
IntegerinitOptionWall213Init Option of Wall
ClaRa.Basics.Units.Temperature[N_cv]T_start_primaryAirones(N_cv)*293.15Start value of primary air system Temperature
ClaRa.Basics.Units.Pressure[N_cv]p_start_primaryAirones(N_cv)*1.013e5Start value of primary air system pressure
ClaRa.Basics.Units.MassFraction[medium.nc - 1]xi_start_primaryAirmedium.xi_defaultStart value of primary air system mass fraction
ClaRa.Basics.Units.Temperature[N_cv]T_start_secondaryAirones(N_cv)*293.15Start value of secondary air system Temperature
ClaRa.Basics.Units.Pressure[N_cv]p_start_secondaryAirones(N_cv)*1.013e5Start value of secondary air system pressure
ClaRa.Basics.Units.MassFraction[medium.nc - 1]xi_start_secondaryAirmedium.xi_defaultStart value of secondary air system mass fraction
ClaRa.Basics.Units.Temperature[N_cv]T_start_flueGasones(N_cv)*400Start value of flue gas system Temperature
ClaRa.Basics.Units.Pressure[N_cv]p_start_flueGasones(N_cv)*1.013e5Start value of flue gas system pressure
ClaRa.Basics.Units.MassFraction[medium.nc - 1]xi_start_flueGasmedium.xi_defaultStart value of flue gas system mass fraction
ClaRa.Basics.Units.Temperature[N_cv]T_start_primary_wallones(N_cv)*350Start value of primary wall Temperature
ClaRa.Basics.Units.Temperature[N_cv]T_start_secondary_wallones(N_cv)*350Start value of secondary wall Temperature
Numerical Efficiency
IntegerstateLocation2Location of wall states
Fundamental Definitions
TILMedia.Gas.Types.BaseGasmediumsimCenter.flueGasModelMedium to be used in cells

Connectors

TypeNameDefaultDescription
ClaRa.Basics.Interfaces.GasPortInflueGasInletInlet port
ClaRa.Basics.Interfaces.GasPortOutflueGasOutletOutlet port
ClaRa.Basics.Interfaces.GasPortInsecondaryAirInletInlet port
ClaRa.Basics.Interfaces.GasPortOutsecondaryAirOutletOutlet port
ClaRa.Basics.Interfaces.GasPortInprimaryAirInletInlet port
ClaRa.Basics.Interfaces.GasPortOutprimaryAirOutletOutlet port
ClaRa.Basics.Interfaces.EyeOutGaseye_air
ClaRa.Basics.Interfaces.EyeOutGaseye_flueGas

Components

TypeNameDefaultDescription
ClaRa.SimCentersimCenter
TILMedia.Solid.Solidsolid
Basics.ControlVolumes.GasVolumes.VolumeGas_L4flueGasCellSecondary
Basics.ControlVolumes.GasVolumes.VolumeGas_L4secondaryAirCell
Basics.ControlVolumes.GasVolumes.VolumeGas_L4flueGasCellPrimary
Basics.ControlVolumes.GasVolumes.VolumeGas_L4primaryAirCell
Basics.ControlVolumes.SolidVolumes.ThinPlateWall_L4wallPrimaryAir
Basics.ControlVolumes.SolidVolumes.ThinPlateWall_L4wallSecondaryAir
VolumesValvesFittings.Valves.ThreeWayValveGas_L1_simpleflueGasSplit
VolumesValvesFittings.Fittings.FlueGasJunction_L2flueGasJoin
VolumesValvesFittings.Valves.ThreeWayValveGas_L1_simpleprimaryLeakage
VolumesValvesFittings.Fittings.FlueGasJunction_L2primaryLeakageJoin
VolumesValvesFittings.Valves.ThreeWayValveGas_L1_simplesecondaryLeakage
VolumesValvesFittings.Fittings.FlueGasJunction_L2secondaryLeakageJoin
Summarysummary
VolumesValvesFittings.Valves.GenericValveGas_L1valveGas_L1_1

Contents

NameDescription
Summary
PressureLoss
HeatTransferFlueGas
HeatTransferSecondaryAir
HeatTransferPrimaryAir
Material

Revisions

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