Thermal Mass
This feature models a node (one-port component) of the thermal system, at which a heat rate P is prescribed to take into account heat storage:
(6-21)
where C (SI unit: J/K) is the thermal capacitance, defined as
with V the volume (SI unit: m3), ρ the density (SI unit: kg/m3), Cp the heat capacity at constant pressure (SI unit: J/(kg·K)), and m the mass (SI unit: kg).
This component is similar to the Thermal Capacitor two-port component, with the difference that the thermal mass has a virtual fixed temperature node.
For a steady-state problem the temperature does not change with time and P = 0.
See Theory for the Thermal Capacitor and Thermal Mass Components for more details on the underlying theory.
Node Connections
Set the Node name for the thermal mass node.
Node Parameters
The thermal capacitance used in Equation 6-21 should be set in this section.
Depending on the option selected in the Specify list, different settings are required:
With Thermal capacitance (default), set directly a value or expression for C.
With Density and heat capacity, set values or expressions for the Volume, V, the Density, ρ, and the Heat capacity at constant pressure, Cp. Select any material from the Material list to define the properties From material. For User defined enter values or expressions.
With Mass and heat capacity, set values or expressions for the Mass, m, and the Heat capacity at constant pressure, Cp. Select any material from the Material list to define Cp From material. For User defined enter a value or expression.
Initial Values
Set a user defined value or expression for the Initial temperature, Tinit, to be used at initialization, in particular to evaluate 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:
Heat rate
Location in User Interface
Context Menus
Ribbon
Physics tab with Lumped Thermal System selected: