Thermoelectric Module
This feature models a two-port source component of the thermal system, used to take into account Peltier effect and Joule heating in a thermoelectric module. It connects two nodes, by creating a difference in the heat rates of its two connecting ports.
It adds equations for the heat rates Pp1 and Pp2 and the temperatures Tp1 and Tp2 at the connecting ports p1 and p2 of the component, and defines the heat rate P as the sum of the heat rates Pp1 and Pp2.
The heat rate applied at each port takes into account the sum of Peltier (cooling or heating) effect, half of the Joule heating, the resistive heating due to conduction in the thermocouples (p-type and n-type semiconductors), and heat storage for time-dependent modeling:
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p1 side:
(6-24)
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p2 side:
(6-25)
where
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S (SI unit: V/K) is the Seebeck coefficient of the thermocouples
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I (SI unit: A) is the electric current operating in the module
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Re (SI unit: Ω) is the electrical resistance of the thermocouples
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ΔT (SI unit: K) is the temperature difference between the two sides of the module
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R (SI unit: K/W) is the thermal resistance of the thermocouples
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C1 and C2 (SI unit: J/K) are the thermal capacitances on each side of the module
For a steady-state problem the temperature does not change with time and the heat storage terms disappear.
When summing Equation 6-24 and Equation 6-25 to obtain the total heat rate through the thermoelectric module, the terms for heat dissipation by conduction cancel each other. Note that the material properties are evaluated at the average temperature of the two ports temperatures.
See Theory for the Thermoelectric Module Component for details.
For a thermoelectric cooler, the ports p1 and p2 correspond respectively to the cold and hot sides of the module, and the cold side is the side where the heat should be removed.
In addition, the total heat rate through the thermoelectric module may be expressed from performance parameters:
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p1 side:
(6-26)
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p2 side:
(6-27)
where
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Qmax (SI unit: W) is the maximum removed heat on the cold side
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ΔT (SI unit: K) is the temperature difference between the two sides of the module
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ΔTmax (SI unit: K) is the maximum temperature difference across the module
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Re (SI unit: Ω) is the electrical resistance of the thermocouples
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I (SI unit: A) is the electric current operating in the module
This alternative formulation may be chosen if the material and geometric properties of the module are not available. See Performance Graphs for Thermoelectric Coolers for details.
Model Input
This section contains fields and values that are inputs for expressions defining material properties. If such user-defined property groups are added, the model inputs appear here.
By default the Temperature is User defined and the average of the two port temperatures, Tave = 0.5*(Tp1+Tp2), is set.
Identifier
Enter a Component name for the thermoelectric module. The prefix is TEM.
Node Connections
Set the two Node names for the nodes connected by the thermoelectric module. Note that for a thermoelectric cooler, the ports p1 and p2 correspond respectively to the cold and hot sides of the module.
Component Parameters
Depending on the available data for the specification of the thermoelectric module and on its operation mode (cooling or heating), different sets of user inputs may be entered:
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Set Specify to Performance parameters, TEC linearized model to use performance graphs (Equation 6-26 and Equation 6-27) to characterize the module. Then, set values or expressions for the operating Electric current, I, and set the other parameters in the Performance Parameters section.
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Set Specify to Performance parameters, general model to apply user defined heat rates on each side of the module. Set values or expressions for the Heat rate, node 1 and the Heat rate, node 2. In this formulation, the nodes 1 and 2 may refer to any side of the module, and the heat rate expressions may depend on the temperature difference and on the current intensity, among other variables. The temperature difference can be accessed through the lts.TEM1.DT variable, when the component name is TEM1, in a physics interface with tag lts.
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Set Specify to Thermal and geometric properties to use Equation 6-24 and Equation 6-25 to characterize the module. Set values or expressions for the operating Electric current, I, and the Number of thermocouples, N (composed each of one p-type and one n-type semiconductors) in the thermoelectric module. Then the material and geometric properties should be set in the P-Type Semiconductor Parameters, N-Type Semiconductor Parameters, and Ceramic Plate Parameters section that display underneath.
Performance Parameters
This section is available when Specify is set to Performance parameters, TEC linearized model in the Component Parameters section.
Set the Maximum heat rate, cold side, Qmax, the Maximum temperature difference, ΔTmax, and the Electrical resistance, Re, used for the expression of the heat rates on each side, following Equation 6-26 and Equation 6-27.
P-Type Semiconductor Parameters
This section is available when Specify is set to Thermal and geometric properties in the Component Parameters section. The material and geometric properties of the p-type semiconductors should be set in this section.
First, set the Seebeck coefficient, Sp.
Electrical and Thermal Resistances
Either specify directly the Electrical resistance, Re,p and Thermal resistance, Rp or specify the Electrical conductivity, σe,p and Thermal conductivity, kp to calculate the corresponding resistances.
Thermal Capacitance
Either specify directly the Thermal capacitance, Cp or specify the Density, ρp and Heat capacity at constant pressure, Cp,p to calculate the corresponding thermal capacitance. For a steady-state problem, heat storage is null and these inputs are ignored.
Geometry Parameters
The Section area, Ap and Length, Lp of the p-type semiconductors are needed when either the resistances are expressed from the conductivities or the capacitance is expressed from the density and heat capacity at constant pressure.
Material
Select any material from the Material list to define some material properties From material. For User defined enter values or expressions for these properties.
N-Type Semiconductor Parameters
This section is available when Specify is set to Thermal and geometric properties in the Component Parameters section. The material and geometric properties of the n-type semiconductors should be set in this section. See P-Type Semiconductor Parameters section for details.
Ceramic Plate Parameters
This section is available when Specify is set to Thermal and geometric properties in the Component Parameters section. The material and geometric properties of the ceramic plates should be set in this section.
Thermal Capacitance
Either specify directly the Thermal capacitance, Cc or specify the Density, ρc and Heat capacity at constant pressure, Cp,c to calculate the corresponding thermal capacitance. For a steady-state problem, heat storage is null and these inputs are ignored.
Geometry Parameters
The Section area, Ac and Thickness, dc of the ceramic plates are needed when the capacitance is expressed from the density and heat capacity at constant pressure.
Material
Select any material from the Material list to define some material properties From material. For User defined enter values or expressions for these properties.
Initial Values
Set user defined values or expressions for the Initial temperature at node 1, T1,init, and the Initial temperature at node 2, T2,init, to be used at initialization, in particular to evaluate the material properties, the performance parameters of the thermoelectric module, and the heat storage term.
Results
Select appropriate options in the Add the following to default results in order to include the following global variables (space-independent) in the default plots:
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 Heat rate
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 Temperature at node 1
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 Temperature at node 2
Location in User Interface
Context Menus
Lumped Thermal System>Thermoelectric Module
Ribbon
Physics Tab with Lumped Thermal System selected:
Global>Thermoelectric Module