Fired Heater¶

DWSIM Plus

Available with a DWSIM Plus (Patreon) subscription.

Fired Heater unit operation. Connections: Inlets: - Process stream (fluid to be heated) - Fuel stream (gaseous/liquid fuel) Outlets: - Heated process stream - Flue gas stream - Energy stream (duty for heat balance) Operating modes: 1. Specify process outlet T -> calculate fuel flow rate 2. Specify duty -> calculate outlet T and fuel flow rate 3. Specify fuel flow rate -> calculate outlet T and duty

DWSIM.UnitOperations.FiredHeater.Models.FiredHeaterUnitOperation
Assembly DWSIM.UnitOperations.FiredHeater.dll · Object ← BaseClass ← UnitOpBaseClass ← FiredHeaterUnitOperation

At a glance¶

Fired Heater in the example flowsheet

Port	Index	Connected in the example
Inlet, material	`0`	Charge
Inlet, material	`1`	Fuel gas
Outlet, material	`0`	Charge-hot
Outlet, material	`1`	Flue gas

Example¶

This code runs on every build of this site, and the output below is what it printed.

Python

# The flue gas outlet needs CO2, water, nitrogen and oxygen in the compound list.
fs = (Flowsheet.Create("FiredHeaterExample")
      .WithCompounds("N-dodecane", "N-hexadecane", "Methane",
                     "Carbon dioxide", "Water", "Nitrogen", "Oxygen")
      .WithPropertyPackage(PropertyPackages.PengRobinson))

charge = (fs.AddMaterialStream("Charge")
          .At(Q.Celsius(200.0), Q.Bar(15.0))
          .SetCompoundMassFlow("N-dodecane", 10.0)
          .SetCompoundMassFlow("N-hexadecane", 10.0))
fuel = (fs.AddMaterialStream("Fuel gas")
        .At(Q.Celsius(25.0), Q.Bar(3.0))
        .SetCompoundMolarFlow("Methane", 10.0))      # first guess; the heater resizes it
hot = fs.AddMaterialStream("Charge-hot")
flue = fs.AddMaterialStream("Flue gas")

heater = (fs.AddFiredHeater("H-101")
          .ConnectFeed(charge, 0).ConnectFeed(fuel, 1)
          .ConnectProduct(hot, 0).ConnectProduct(flue, 1))
heater.Object.SpecifiedOutletTemperature = 273.15 + 300.0   # K

cfg = heater.Config
cfg.SpecMode = FurnaceSpecMode.OutletTemperature     # the fuel flow is solved for
cfg.ExcessAir = 0.15                                 # 15 % excess air
conv = cfg.ConvectionSection                         # 3 rows of 8 finned tubes, 10 m long
conv.NumberOfTubes = 24
conv.NumberOfRows = 3
conv.DuctWidth = 1.75                                # m
conv.FinType = FinType.SolidFin

fs.AutoLayout()
fs.Solve()

r = heater.Object.Results
print(f"Duty absorbed      = {r.TotalDutyAbsorbed / 1e6:.2f} MW")
print(f"Heat released      = {r.TotalHeatReleased / 1e6:.2f} MW")
print(f"Thermal efficiency = {r.ThermalEfficiency * 100:.1f} %")
print(f"Fuel consumption   = {r.FuelConsumption * 3600:.0f} kg/h")
print(f"Bridgewall T       = {r.RadiantSection.BridgewallTemperature - 273.15:.0f} C")
print(f"Flue gas T         = {flue.TemperatureK - 273.15:.0f} C")

Output

Duty absorbed      = 6.00 MW
Heat released      = 6.74 MW
Thermal efficiency = 89.0 %
Fuel consumption   = 485 kg/h
Bridgewall T       = 1079 C
Flue gas T         = 219 C

DWSIM 10.2.11.0, generated 2026-10-08.

Properties¶

IDs accepted by GetPropertyValue, SetPropertyValue, the sensitivity analysis, the optimizer, the Adjust block and dynamic events. Units are SI; pass another unit system to GetPropertyValue to get them converted.

All 93 properties

ID	Unit (SI)	Input
`Furnace Type`		yes
`Draft Type`		yes
`Specification Mode`		yes
`Specified Outlet Temperature`	K	yes
`Specified Duty`	kW	yes
`Internal Heat Transfer Coefficient`	W/[m.K]	yes
`Excess Air`	%	yes
`Wall Heat Loss Fraction`	%	yes
`Radiant Chamber Length`	m	yes
`Radiant Chamber Width`	m	yes
`Radiant Chamber Height`	m	yes
`Radiant Tube Outer Diameter`	mm	yes
`Radiant Tube Wall Thickness`	mm	yes
`Radiant Tube Effective Length`	m	yes
`Radiant Number of Tubes`		yes
`Radiant Number of Passes`		yes
`Radiant Tube Pitch`	m	yes
`Radiant Tube-to-Wall Distance`	m	yes
`Radiant Tube Thermal Conductivity`	W/[m.K]	yes
`Radiant Tube Emissivity`	NF	yes
`Radiant Refractory Emissivity`	NF	yes
`Radiant Refractory Thickness`	mm	yes
`Radiant Refractory Conductivity`	W/[m.K]	yes
`Convection Tube Outer Diameter`	mm	yes
`Convection Tube Wall Thickness`	mm	yes
`Convection Tube Effective Length`	m	yes
`Convection Number of Tubes`		yes
`Convection Number of Rows`		yes
`Convection Number of Passes`		yes
`Convection Transverse Pitch`	m	yes
`Convection Longitudinal Pitch`	m	yes
`Convection Tube Thermal Conductivity`	W/[m.K]	yes
`Convection Tube Arrangement`		yes
`Convection Fin Type`		yes
`Convection Fin Height`	m	yes
`Convection Fin Thickness`	mm	yes
`Convection Fin Density`	fins/m	yes
`Convection Fin Thermal Conductivity`	W/[m.K]	yes
`Convection Duct Width`	m	yes
`Convection Duct Height`	m	yes
`Shield Section Enabled`		yes
`Shield Number of Rows`		yes
`Shield Number of Tubes`		yes
`Shield Tube Outer Diameter`	mm	yes
`Shield Tube Effective Length`	m	yes
`Shield Radiant Fraction`	%	yes
`Stack Height`	m	yes
`Stack Inner Diameter`	mm	yes
`Stack Ambient Temperature`	K	yes
`Stack Ambient Pressure`	Pa	yes
`Stack Ambient Relative Humidity`	%	yes
`Total Duty Absorbed`	kW	result
`Total Heat Released`	kW	result
`Thermal Efficiency`	%	result
`Fuel Consumption`	kg/s	result
`Process Outlet Temperature`	K	result
`Flue Gas Outlet Temperature`	K	result
`Adiabatic Flame Temperature`	K	result
`Fuel LHV (mass)`	kJ/kg	result
`Air Mass Flow`	kg/s	result
`Flue Gas Total Mass Flow`	kg/s	result
`Flue Gas CO2 Mole Fraction`	%	result
`Flue Gas H2O Mole Fraction`	%	result
`Flue Gas O2 Mole Fraction`	%	result
`Flue Gas N2 Mole Fraction`	%	result
`Radiant Duty Absorbed`	kW	result
`Radiant Fraction of Total Duty`	%	result
`Bridgewall Temperature`	K	result
`Radiant Average Heat Flux`	W/m²	result
`Radiant Maximum Heat Flux`	W/m²	result
`Average Tube Skin Temperature`	K	result
`Maximum Tube Skin Temperature`	K	result
`Gas Emissivity`		result
`Exchange Factor`		result
`Mean Beam Length`	m	result
`Shield Duty Absorbed`	kW	result
`Shield Gas Outlet Temperature`	K	result
`Convection Duty Absorbed`	kW	result
`Convection LMTD`	K (difference)	result
`Overall Heat Transfer Coefficient`	W/[m2.K]	result
`External Heat Transfer Coefficient`	W/[m2.K]	result
`Convection Reynolds Number`		result
`Fin Efficiency`		result
`Stack Exit Temperature`	K	result
`Available Draft`	Pa	result
`Net Draft`	Pa	result
`Stack Velocity`	m/s	result
`Stack Loss Fraction`	%	result
`Stack Volumetric Flow`	m3/s	result
`CO2 Mass Flow`	kg/s	result
`SO2 Mass Flow`	kg/s	result
`NOx Concentration`	mg/Nm³	result
`NOx Mass Flow`	kg/s	result

Learn more¶

User guide
- Fired Heater
FluentAPI
- Plus.FiredHeaterBuilder

API members¶

Public members declared by this class. Inherited members are documented on the base classes.

Constructors¶

FiredHeaterUnitOperation()

C#VB.NET

public FiredHeaterUnitOperation()

Public Sub New()

Properties¶

ComponentDescription: Gets or sets the CAPE-OPEN component description for this unit operation.

Gets or sets the CAPE-OPEN component description for this unit operation.

C#VB.NET

public override string ComponentDescription { get; set; }

Public Overrides Property ComponentDescription As String

Config: Gets or sets the fired heater configuration: furnace and draft type, specification mode, excess air, wall heat loss...

Gets or sets the fired heater configuration: furnace and draft type, specification mode, excess air, wall heat loss, and the radiant, shield, convection and stack geometry.

C#VB.NET

public FiredHeaterConfiguration Config { get; set; }

Public Property Config As FiredHeaterConfiguration

Description: Gets the description of this unit operation type.

Gets the description of this unit operation type.

C#VB.NET

public string Description { get; }

Public ReadOnly Property Description As String

InternalHeatTransferCoefficient: Internal fluid heat transfer coefficient [W/(m²·K)] - may be calculated externally

Internal fluid heat transfer coefficient [W/(m²·K)] - may be calculated externally

C#VB.NET

public double InternalHeatTransferCoefficient { get; set; }

Public Property InternalHeatTransferCoefficient As Double

IsPremium: Gets a value indicating that this unit operation is listed in the Premium group of the object palette (always true).

Gets a value indicating that this unit operation is listed in the Premium group of the object palette (always true).

C#VB.NET

public bool IsPremium { get; }

Public ReadOnly Property IsPremium As Boolean

MobileCompatible: Gets a value indicating whether this unit operation is compatible with mobile interfaces.

Gets a value indicating whether this unit operation is compatible with mobile interfaces.

C#VB.NET

public override bool MobileCompatible { get; }

Public Overrides ReadOnly Property MobileCompatible As Boolean

ObjectClass: Gets or sets the simulation object class category (Exchangers).

Gets or sets the simulation object class category (Exchangers). The setter always stores Exchangers.

C#VB.NET

public override SimulationObjectClass ObjectClass { get; set; }

Public Overrides Property ObjectClass As SimulationObjectClass

Prefix: Gets the default name prefix for this unit operation.

Gets the default name prefix for this unit operation.

C#VB.NET

public string Prefix { get; }

Public ReadOnly Property Prefix As String

SpecifiedDuty: Specified duty [W] (for Duty mode)

Specified duty [W] (for Duty mode)

C#VB.NET

public double SpecifiedDuty { get; set; }

Public Property SpecifiedDuty As Double

SpecifiedOutletTemperature: Specified outlet temperature [K] (for OutletTemperature mode)

Specified outlet temperature [K] (for OutletTemperature mode)

C#VB.NET

public double SpecifiedOutletTemperature { get; set; }

Public Property SpecifiedOutletTemperature As Double

Methods¶

Calculate(object): Executes the full Fired Heater calculation.

Executes the full Fired Heater calculation. This is the main method called by the DWSIM solver.

Parameter	Type	Description
`args`	`Object`

C#VB.NET

public override void Calculate(object args = null)

Public Overrides Sub Calculate(args As Object = Nothing)

CloneXML(): Creates a deep copy of this object by round-tripping through XML serialization.

Creates a deep copy of this object by round-tripping through XML serialization.

C#VB.NET

public override object CloneXML()

Public Overrides Function CloneXML() As Object

CloseEditForm(): Closes the editor of this object, if it is open.

Closes the editor of this object, if it is open.

C#VB.NET

public override void CloseEditForm()

Public Overrides Sub CloseEditForm()

CreateConnectors(): Creates the graphic connector definitions on the flowsheet: process and fuel inlets, process outlet, and the flue...

Creates the graphic connector definitions on the flowsheet: process and fuel inlets, process outlet, and the flue gas outlet.

C#VB.NET

public void CreateConnectors()

Public Sub CreateConnectors()

DisplayEditForm(): Opens the editor of this object.

Opens the editor of this object. A host that has no editor for it does nothing.

C#VB.NET

public override void DisplayEditForm()

Public Overrides Sub DisplayEditForm()

Draw(object): Draws the unit operation icon on the given SkiaSharp canvas.

Draws the unit operation icon on the given SkiaSharp canvas.

Parameter	Type	Description
`g`	`Object`	The SkiaSharp canvas.

C#VB.NET

public void Draw(object g)

Public Sub Draw(g As Object)

GetDisplayDescription(): Returns the localized description string for this unit operation type.

Returns the localized description string for this unit operation type.

C#VB.NET

public override string GetDisplayDescription()

Public Overrides Function GetDisplayDescription() As String

GetDisplayName(): Returns the localized display name for this unit operation type.

Returns the localized display name for this unit operation type.

C#VB.NET

public override string GetDisplayName()

Public Overrides Function GetDisplayName() As String

GetIconBitmapBytes(): Returns the raw bytes of the icon image for this unit operation.

Returns the raw bytes of the icon image for this unit operation.

C#VB.NET

public override byte[] GetIconBitmapBytes()

Public Overrides Function GetIconBitmapBytes() As Byte()

GetPreferredGraphicObjectHeight(): Returns the preferred height of the flowsheet graphic object, in pixels.

Returns the preferred height of the flowsheet graphic object, in pixels.

C#VB.NET

public override double GetPreferredGraphicObjectHeight()

Public Overrides Function GetPreferredGraphicObjectHeight() As Double

GetPreferredGraphicObjectWidth(): Returns the preferred width of the flowsheet graphic object, in pixels.

Returns the preferred width of the flowsheet graphic object, in pixels.

C#VB.NET

public override double GetPreferredGraphicObjectWidth()

Public Overrides Function GetPreferredGraphicObjectWidth() As Double

GetProperties(PropertyType): Get a list of all properties of the object.

Get a list of all properties of the object.

Parameter	Type	Description
`proptype`	`PropertyType`	Type of the property.

C#VB.NET

public override string[] GetProperties(PropertyType proptype)

Public Overrides Function GetProperties(proptype As PropertyType) As String()

GetPropertyUnit(string, IUnitsOfMeasure): Gets the units of a property.

Gets the units of a property.

Parameter	Type	Description
`prop`	`String`	Property identifier.
`su`	`IUnitsOfMeasure`	Units system to use. Null to use the default (SI) system.

C#VB.NET

public override string GetPropertyUnit(string prop, IUnitsOfMeasure su = null)

Public Overrides Function GetPropertyUnit(prop As String, su As IUnitsOfMeasure = Nothing) As String

GetPropertyValue(string, IUnitsOfMeasure): Returns the value of a named property, converting from SI to the current unit system.

Returns the value of a named property, converting from SI to the current unit system. Falls back to extra properties if the property is not found in the base implementation.

Parameter	Type	Description
`prop`	`String`	The property identifier string.
`su`	`IUnitsOfMeasure`	Optional units-of-measure system used for conversion; uses the shared SI system when `Nothing`.

C#VB.NET

public override object GetPropertyValue(string prop, IUnitsOfMeasure su = null)

Public Overrides Function GetPropertyValue(prop As String, su As IUnitsOfMeasure = Nothing) As Object

LoadData(List<XElement>): Restores the unit operation state from a list of XML elements previously produced by SaveData.

Restores the unit operation state from a list of XML elements previously produced by SaveData.

Parameter	Type	Description
`data`	`List<XElement>`	The list of `XElement` objects containing serialized state.

C#VB.NET

public override bool LoadData(List<XElement> data)

Public Overrides Function LoadData(data As List(Of XElement)) As Boolean

PopulateEditorPanel(object): Populates the cross-platform editor panel with controls.

Populates the cross-platform editor panel with controls.

Parameter	Type	Description
`ctner`	`Object`	The editor panel (layout container) to populate.

C#VB.NET

public void PopulateEditorPanel(object ctner)

Public Sub PopulateEditorPanel(ctner As Object)

ReturnInstance(string): Creates and returns a new instance for deserialization.

Creates and returns a new instance for deserialization.

Parameter	Type	Description
`typename`	`String`	The type name to instantiate.

C#VB.NET

public object ReturnInstance(string typename)

Public Function ReturnInstance(typename As String) As Object

SaveData(): Serializes the unit operation state to a list of XML elements for persistence.

Serializes the unit operation state to a list of XML elements for persistence.

C#VB.NET

public override List<XElement> SaveData()

Public Overrides Function SaveData() As List(Of XElement)

SetPropertyValue(string, object, IUnitsOfMeasure): Sets the value of a property.

Sets the value of a property.

Parameter	Type	Description
`prop`	`String`	Property identifier.
`propval`	`Object`	Property value to set at the specified units.
`su`	`IUnitsOfMeasure`	Units system to use. Null to use the default (SI) system.

C#VB.NET

public override bool SetPropertyValue(string prop, object propval, IUnitsOfMeasure su = null)

Public Overrides Function SetPropertyValue(prop As String, propval As Object, su As IUnitsOfMeasure = Nothing) As Boolean

UpdateEditForm(): Redraws the editor of this object with the current values, if it is open.

Redraws the editor of this object with the current values, if it is open.

C#VB.NET

public override void UpdateEditForm()

Public Overrides Sub UpdateEditForm()

Fields¶

f: The classic (WinForms) editor window open for this unit operation, if any.

The classic (WinForms) editor window open for this unit operation, if any. Not saved with the flowsheet.

C#VB.NET

public FormEditorFiredHeater f

Public f As FormEditorFiredHeater