Heat flow source

Injects the input heat flow (W) into its port.

  • signal
  • thermal
  • Modelica Standard Library
  • 2 ports
BlockHeat flow sourceKindprescribedHeatFlowLibraryThermal

Description

Injects the heat flow given by an input signal into whatever its port is connected to. Use it to feed computed losses, for example electrical power dissipation, into a thermal model.

Example

Cooling a hot part A 10 W part cools through a thermal resistance into a heatsink that convects and radiates to 20 °C.

10 WPart 100 J/KHeat flowR 2 K/WHeatsink 500 J/Kh·A 5 W/KConvectionAir 20 °CRadiationRoom 20 °CPart temperatureAcross R350 KHeld at 350 KG 1 W/KBody 100 J/K20 W at 1500 sHeaterBody temperature
In Gradara, select a Heat flow source block and press F1, then choose Open example. It opens as a new model in My models, ready to run.

Also in this example:ConstantStepHeat capacitorThermal conductorThermal resistorConvectionRadiationFixed temperatureTemperature sourceFixed heat flowTemperature sensorHeat flow sensorTemperature difference sensor

Ports

Inputs 1

  • QQ_flowsignal · W

    Heat flow to inject, in watts. Positive heats the connected network.

Conserving terminals 1

  • Qportthermal

    Heat port. The block delivers Q_flow out of this port.

Equations

Modelica
port.Q_flow = −Q_flow

Implementation

Modelica Standard Library 4.1.0Modelica.Thermal.HeatTransfer.Sources.PrescribedHeatFlow
MSL documentation

Tips

  • Pair it with Power sensor to turn a component’s electrical loss into heat.

Used in

These larger examples use it too. Open them from Examples in the app.

  • Data center cooling control

See also

Select a block in Gradara and press F1 to open its page offline.