Thermal modeling

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JuliaSimStdLib contains basic thermal components for modeling heat transfer and fluid heat flow.

Basic thermal components

Thermal ground

Function: ThermalGround(;name)

Description: Thermal port for 1-dimensional heat transfer with temperature set to zero. Note that specifying the macro @named sys = ThermalGround() is equivalent to setting sys = ThermalGround(;name, sys). Either method will suffice, and there is no need to type the name twice. The same principle applies to the other thermal components.

Heat capacitor

Function: HeatCapacitor(;name, C = 1.0)

Observables:

  • C: heat capacity (zero or positive)

State:

  • temperature (in Kelvin)

Connectors:

  • heat port

Thermal conductor

Function: ThermalConductor(;name, G = 1.0)

Observables:

  • G: thermal conductance

Connectors:

  • two heat ports

Thermal resistor

Function: ThermalResistor(;name, R = 1.0)

Description: The model operates on the same principle as ThermalConductor, but relies on thermal resistance instead of thermal conductance.

Observables:

  • R: thermal resistance

Connectors:

  • two heat ports

Convective conductor

Function: ConvectiveConductor(;name; G = 1.0)

Description: Model of linear heat convection.

Observables:

  • G: convective thermal conductance

Connectors:

  • two heat ports (for modeling of the fluid flow over the solid)

Convective resistor

Function: ConvectiveResistor(;name; R = 1.0)

Description: Model of linear heat convection. Works analogously to the above model, but relies on convective thermal resistance instead of convenctive thermal conductance.

Observables:

  • R: convective thermal resistance

Connectors:

  • two heat ports (for modeling of the fluid flow over the solid)

Thermal radiation

Function: BodyRadiation(;name; G = 1.0)

Description: Thermal radiation model.

Observables:

  • G: net radiation conductance between two surfaces

  • Stefan-Boltzmann constant

Connectors:

  • two heat ports


Thermal sensors

Temperature sensor

Function: TemperatureSensor(;name)

Description: Ideal absolute temperature sensor which outputs the temperature (in Kelvin) of the connected port.

Connectors:

  • heat port

Relative temperature sensor

Function: RelativeTemperatureSensor(;name)

Description: The output of the sensor is the relative temperature, i.e., the difference of the two ports, given in Kelvin.

Connectors:

  • two heat ports

Heat flow sensor

Function: HeatFlowSensor(;name)

Description: The model monitors the heat flow rate of the component. Its output is positive when the direction the heat flow is from the first port to the second one.

Connectors:

  • two heat ports


Thermal sources

Fixed heat flow

Function: FixedHeatFlow(;name, Q_flow=1.0, T₀=293.15, α=0.0)

Observables:

  • Q_flow: the constant amount of heat flow rate

  • T₀: the reference temperature

  • α: this parameter simulates temperature-dependent loss (if the specified value is not 0)

Connectors:

  • heat port

Fixed temperature

Function: FixedTemperature(;name, T = 0.0)

Description: The model defines a fixed temperature (in Kelvin) at a given port.

Observables:

  • T: temperature (in Kelvin)

Connectors:

  • heat port