Description: "Thermal sources"

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## Buildings.HeatTransfer.Sources

Thermal sources

### Information

This package is identical to Modelica.Thermal.HeatTransfer.Sources, except that the parameters `alpha` and `T_ref` have been deleted in the models Modelica.Thermal.HeatTransfer.Sources.FixedHeatFlow and Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow as these can cause division by zero in some fluid flow models.

Extends from Modelica.Icons.SourcesPackage (Icon for packages containing sources).

### Package Content

Name | Description
--- | ---
FixedHeatFlow | Fixed heat flow boundary condition
FixedTemperature | Fixed temperature boundary condition in Kelvin
PrescribedHeatFlow | Prescribed heat flow boundary condition
PrescribedTemperature | Variable temperature boundary condition in Kelvin

## Buildings.HeatTransfer.Sources.FixedHeatFlow

Fixed heat flow boundary condition

### Information

This model allows a specified amount of heat flow rate to be "injected" into a thermal system at a given port. The constant amount of heat flow rate Q_flow is given as a parameter. The heat flows into the component to which the component FixedHeatFlow is connected, if parameter Q_flow is positive.

This model is identical to Modelica.Thermal.HeatTransfer.Sources.FixedHeatFlow, except that the parameters `alpha` and `T_ref` have been deleted as these can cause division by zero in some fluid flow models.

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
HeatFlowRate | Q_flow |  | Fixed heat flow rate at port [W]

### Connectors

Type | Name | Description
--- | --- | ---
HeatPort_b | port |

### Modelica definition

model FixedHeatFlow "Fixed heat flow boundary condition" parameter Modelica.SIunits.HeatFlowRate Q_flow "Fixed heat flow rate at port"; Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_b port; equation port.Q_flow = -Q_flow; end FixedHeatFlow;

## Buildings.HeatTransfer.Sources.FixedTemperature

Fixed temperature boundary condition in Kelvin

### Information

This model defines a fixed temperature T at its port in Kelvin, i.e., it defines a fixed temperature as a boundary condition.

### Parameters

Type | Name | Default | Description
--- | --- | --- | ---
Temperature | T |  | Fixed temperature at port [K]

### Connectors

Type | Name | Description
--- | --- | ---
HeatPort_b | port |

### Modelica definition

model FixedTemperature "Fixed temperature boundary condition in Kelvin" parameter Modelica.SIunits.Temperature T "Fixed temperature at port"; Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_b port; equation port.T = T; end FixedTemperature;

## Buildings.HeatTransfer.Sources.PrescribedHeatFlow

Prescribed heat flow boundary condition

### Information

This model allows a specified amount of heat flow rate to be "injected" into a thermal system at a given port. The amount of heat is given by the input signal Q_flow into the model. The heat flows into the component to which the component PrescribedHeatFlow is connected, if the input signal is positive.

This model is identical to Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow, except that the parameters `alpha` and `T_ref` have been deleted as these can cause division by zero in some fluid flow models.

### Connectors

Type | Name | Description
--- | --- | ---
input RealInput | Q_flow |
HeatPort_b | port |

### Modelica definition

model PrescribedHeatFlow "Prescribed heat flow boundary condition" Modelica.Blocks.Interfaces.RealInput Q_flow; Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_b port; equation port.Q_flow = -Q_flow; end PrescribedHeatFlow;

## Buildings.HeatTransfer.Sources.PrescribedTemperature

Variable temperature boundary condition in Kelvin

### Information

This model represents a variable temperature boundary condition. The temperature in [K] is given as input signal T to the model. The effect is that an instance of this model acts as an infinite reservoir able to absorb or generate as much energy as required to keep the temperature at the specified value.

### Connectors

Type | Name | Description
--- | --- | ---
HeatPort_b | port |
input RealInput | T |

### Modelica definition

model PrescribedTemperature "Variable temperature boundary condition in Kelvin" Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_b port; Modelica.Blocks.Interfaces.RealInput T; equation port.T = T; end PrescribedTemperature;