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

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": 900, "y1": 400, "x2": 1100, "y2": 600}}
    }
  }]
  # Input signal defining the prescribed base heat flow rate
  Q = RealInput() [{"Dyad": {"placement": {"icon": {"x1": -100, "y1": 400, "x2": 100, "y2": 600}}}}]
  # 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))
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": 900, "y1": 400, "x2": 1100, "y2": 600}}
    }
  }]
  # Input signal defining the prescribed base heat flow rate
  Q = RealInput() [{"Dyad": {"placement": {"icon": {"x1": -100, "y1": 400, "x2": 100, "y2": 600}}}}]
  # 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 {}
end

Test Cases

No test cases defined.

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