FEM ConstraintHeatflux: Difference between revisions

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Defines a convective heat flux load on a surface at a temperature ''T'' with a film coefficient ''h'' and with the environment (sink) temperature ''T<sub>0</sub>''. The convective heat flux ''q'' will satisfy: '''''q = h(T -T<sub>0</sub>)'''''. Optionally, can also define a regular surface heat flux.
Defines a convective heat flux load on a surface at a temperature ''T'' with a film coefficient ''h'' and with the environment (sink) temperature ''T<sub>0</sub>''. The convective heat flux ''q'' will satisfy: '''''q = h(T -T<sub>0</sub>)'''''. Optionally, can also define a regular surface heat flux load.

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{{Version|1.0}}: Can be also used to define a radiation heat flux on a surface.


==Usage== <!--T:3-->
==Usage== <!--T:3-->
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#* Press the {{Button|[[Image:FEM_ConstraintHeatflux.svg|16px]] [[FEM_ConstraintHeatflux|Heat flux load]]}} button.
#* Press the {{Button|[[Image:FEM_ConstraintHeatflux.svg|16px]] [[FEM_ConstraintHeatflux|Heat flux load]]}} button.
#* Select the {{MenuCommand|Model → Thermal boundary conditions and loads → [[Image:FEM_ConstraintHeatflux.svg|16px]] Heat flux load}} option from the menu.
#* Select the {{MenuCommand|Model → Thermal boundary conditions and loads → [[Image:FEM_ConstraintHeatflux.svg|16px]] Heat flux load}} option from the menu.
# In the [[3D_view|3D view]] select the face(s) the constraint should be applied to.
# In the [[3D_view|3D view]] select the face(s) the heat flux load should be applied to.
# Enter the desired surface temperature, heat transfer coefficient and environment temperature.
# Enter the desired heat transfer coefficient and environment temperature.

===Options=== <!--T:13-->

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By default, this feature defines a convective heat flux. By using the option '''Surface heat flux''', one can specify a heat flux value in Watts per surface area (W/m^2).

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{{Version|1.0}}: By using the option '''Surface Radiation''', one can specify a radiation heat flux by setting a proper surface emissivity and ambient temperature.


==Notes== <!--T:5-->
==Notes== <!--T:5-->


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* The constraint uses the *FILM card in CalculiX. The heatflux constraint is explained at http://web.mit.edu/calculix_v2.7/CalculiX/ccx_2.7/doc/ccx/node203.html
* The heat flux load uses the [http://web.mit.edu/calculix_v2.7/CalculiX/ccx_2.7/doc/ccx/node203.html *FILM card in CalculiX].
* The '''Surface heat flux''' option uses the [http://web.mit.edu/calculix_v2.7/CalculiX/ccx_2.7/doc/ccx/node188.html *DFLUX card in CalculiX].
* {{Version|1.0}}: The '''Surface Radiation''' option uses the [http://web.mit.edu/calculix_v2.7/CalculiX/ccx_2.7/doc/ccx/node234.html *RADIATE card in CalculiX].





Revision as of 07:31, 6 May 2024

FEM ConstraintHeatflux

Menu location
Model → Thermal boundary conditions and loads → Heat flux load
Workbenches
FEM
Default shortcut
None
Introduced in version
-
See also
FEM tutorial

Description

Defines a convective heat flux load on a surface at a temperature T with a film coefficient h and with the environment (sink) temperature T0. The convective heat flux q will satisfy: q = h(T -T0). Optionally, can also define a regular surface heat flux load.

introduced in version 1.0: Can be also used to define a radiation heat flux on a surface.

Usage

  1. There are several ways to invoke the command:
    • Press the Heat flux load button.
    • Select the Model → Thermal boundary conditions and loads → Heat flux load option from the menu.
  2. In the 3D view select the face(s) the heat flux load should be applied to.
  3. Enter the desired heat transfer coefficient and environment temperature.

Options

By default, this feature defines a convective heat flux. By using the option Surface heat flux, one can specify a heat flux value in Watts per surface area (W/m^2).

introduced in version 1.0: By using the option Surface Radiation, one can specify a radiation heat flux by setting a proper surface emissivity and ambient temperature.

Notes