PrescribedHeatFlow

Models a prescribed heat flow rate at a thermal port, with optional temperature dependency.

This component defines a boundary condition that injects or extracts a specified heat flow rate at its thermal node. The primary heat flow rate is determined by the external input signal Q. A positive Q value indicates that heat is flowing from this component into the system connected to node. The model can also account for temperature-dependent variations in the heat flow. If the parameter alpha is set to a value greater than zero, the heat flow is adjusted by a factor proportional to the difference between the temperature at the port (node.T) and a specified reference temperature (T_ref). This allows for simulating effects like temperature-dependent losses or efficiencies. The core behavior is defined by the equation:

$$\text{node.Q}=-Q\cdot (1+\alpha \cdot (\text{node.T}-T_{\text{ref}}))$$

Usage

ThermalComponents.PrescribedHeatFlow(T_ref=293.15, alpha=0.0)

Parameters:

Name	Description	Units	Default value
T_ref	Reference temperature for calculating temperature-dependent heat flow	K	293.15
alpha	Temperature coefficient that scales the heat flow based on temperature difference	1/K	0

Connectors

• node - This connector represents a thermal node with temperature and heat flow as the potential and flow variables, respectively. (Node)

• Q - This connector represents a real signal as an input to a component (RealInput)

Behavior

$$\begin{array}{rl}\mathtt{node}\mathtt{.}\mathtt{Q}\left(t\right)& =-(1+(-\mathtt{T}\mathtt{\_}\mathtt{ref}+\mathtt{node}\mathtt{.}\mathtt{T}\left(t\right))\mathtt{alpha})Q\left(t\right)\end{array}$$

Source

"""
Models a prescribed heat flow rate at a thermal port, with optional temperature dependency.

This component defines a boundary condition that injects or extracts a specified
heat flow rate at its thermal `node`. The primary heat flow rate is determined by
the external input signal `Q`. A positive `Q` value indicates that heat
is flowing from this component into the system connected to `node`. The model can
also account for temperature-dependent variations in the heat flow. If the
parameter `alpha` is set to a value greater than zero, the heat flow is adjusted
by a factor proportional to the difference between the temperature at the port
(`node.T`) and a specified reference temperature (`T_ref`). This allows for
simulating effects like temperature-dependent losses or efficiencies. The core
behavior is defined by the equation:

math \text{node.Q} = -Q \cdot (1 + \alpha \cdot (\text{node.T} - T_{\text{ref}}))

"""
component PrescribedHeatFlow
  "Acausal thermal port through which heat is exchanged"
  node = Node() {
    "Dyad": {
      "placement": {"icon": {"iconName": "node_b", "x1": 950, "y1": 450, "x2": 1050, "y2": 550}}
    }
  }
  "Input signal defining the prescribed base heat flow rate"
  Q = RealInput() {"Dyad": {"placement": {"icon": {"x1": -50, "y1": 450, "x2": 50, "y2": 550}}}}
  "Reference temperature for calculating temperature-dependent heat flow"
  parameter T_ref::Temperature = 293.15
  "Temperature coefficient that scales the heat flow based on temperature difference"
  parameter alpha::LinearTemperatureCoefficient = 0.0
relations
  node.Q = -Q * (1 + alpha * (node.T - T_ref))
metadata {
  "Dyad": {
    "labels": [{"label": "$(instance)", "x": 500, "y": 1100, "rot": 0}],
    "icons": {"default": "dyad://ThermalComponents/PrescribedHeatFlow.svg"}
  }
}
end

Flattened Source

"""
Models a prescribed heat flow rate at a thermal port, with optional temperature dependency.

This component defines a boundary condition that injects or extracts a specified
heat flow rate at its thermal `node`. The primary heat flow rate is determined by
the external input signal `Q`. A positive `Q` value indicates that heat
is flowing from this component into the system connected to `node`. The model can
also account for temperature-dependent variations in the heat flow. If the
parameter `alpha` is set to a value greater than zero, the heat flow is adjusted
by a factor proportional to the difference between the temperature at the port
(`node.T`) and a specified reference temperature (`T_ref`). This allows for
simulating effects like temperature-dependent losses or efficiencies. The core
behavior is defined by the equation:

math \text{node.Q} = -Q \cdot (1 + \alpha \cdot (\text{node.T} - T_{\text{ref}}))

"""
component PrescribedHeatFlow
  "Acausal thermal port through which heat is exchanged"
  node = Node() {
    "Dyad": {
      "placement": {"icon": {"iconName": "node_b", "x1": 950, "y1": 450, "x2": 1050, "y2": 550}}
    }
  }
  "Input signal defining the prescribed base heat flow rate"
  Q = RealInput() {"Dyad": {"placement": {"icon": {"x1": -50, "y1": 450, "x2": 50, "y2": 550}}}}
  "Reference temperature for calculating temperature-dependent heat flow"
  parameter T_ref::Temperature = 293.15
  "Temperature coefficient that scales the heat flow based on temperature difference"
  parameter alpha::LinearTemperatureCoefficient = 0.0
relations
  node.Q = -Q * (1 + alpha * (node.T - T_ref))
metadata {
  "Dyad": {
    "labels": [{"label": "$(instance)", "x": 500, "y": 1100, "rot": 0}],
    "icons": {"default": "dyad://ThermalComponents/PrescribedHeatFlow.svg"}
  }
}
end

Test Cases

No test cases defined.

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