FEM ConstraintTemperature

Description

Defines a temperature boundary condition or, optionally, a concentrated heat flux load.

2D plate subjected to temperature difference

Usage

1. There are several ways to invoke the command:
   • Press the Temperature Boundary Condition button.
   • Select the Model → Thermal Boundary Conditions and Loads → Temperature Boundary Condition option from the menu.
2. Press the Add button.
3. In the 3D view select the objects the boundary condition should be applied to, which can be vertices, edges, or faces. Optionally, press the Remove button and click on the objects that you want to remove from the selection.
4. Choose the constraint type and specify its parameter:
   • Temperature (default) - temperature boundary condition, enter the Temperature (K)
   • CFlux - concentrated heat flux load, enter the Concentrated heat flux (mW) - this value will be divided by the number of nodes on the underlying geometrical entity to achieve a total flux of a given magnitude on that entity

Properties

• DataEnable Amplitude - introduced in 1.1: Enables the use of CalculiX's amplitude for the time variation of the temperature boundary condition. At a given time, magnitude of the boundary condition is multiplied by the amplitude value corresponding to that time. Linear interpolation is used between the specified values. Constant values are used outside of the specified range.
• DataAmplitude Values - introduced in 1.1: Amplitude table in the following format:

time_1, amplitude_value_1
...

Default is linear increase from 0% at t=0 to 100% at t=1:

0, 0
1, 1

Notes

• The temperature boundary condition uses the *BOUNDARY card in CalculiX.
• The Concentrated heat flux option uses the *CFLUX card in CalculiX.