CAE Software【Femtet】Murata Software Co., Ltd.
A disc is inserted in a space created by two plates.The heat radiation from a plate to the other is blocked by the disc.
A problem similar to [Example 16: Radiation Blocked by a Disc (Steady-state Analysis) ] is set up in a simpler way.
(Refer to the default setting of [Radiation: Equations and Setting Method.)
The temperature distribution and the heat flux vectors are solved.
Unless specified in the list below, the default conditions are applied.
Item |
Setting |
Analysis Space |
3D |
Model Unit |
mm |
Item |
Setting |
Solver |
Thermal analysis [Watt] |
Analysis Type |
Steady-state analysis |
Analysis Options |
None |
A disc is placed in between two plates.
The temperature of the bottom face of the lower plate is fixed at 1000[deg]. The natural convection and surface-to-surface radiation are set to the surroundings.
How the disc affects the radiation to the upper plate is analyzed.
Body Number/Type |
Body Attribute Name |
Material Name |
0/Solid |
Plate_1 |
008_Cu |
1/Solid |
Disk |
002_Polycarbonate(PC) |
2/Solid |
Plate_2 |
002_Polycarbonate(PC) |
The emissivity of each body attribute surface is set as follows.
Body Attribute Name |
Tab |
Setting |
Plate_1 |
Thermal Surface |
Emissivity: 0.5 |
Plate_2 |
Thermal Surface |
Emissivity: 0.5 |
Disk |
Thermal Surface |
Emissivity: 0.99 |
The boundary conditions are set as follows:
Boundary Condition Name/Topology |
Tab |
Boundary Condition Type |
Setting |
Outer Boundary Condition |
Thermal |
Heat Transfer: Convection |
Natural convection (automatic calculation) Radiation type: Surface-to-surface (accuracy prioritized) |
HighTemperatureWall/Face |
Thermal |
Temperature |
1000[deg] Radiation type: Follow the outer boundary condition |
0/Face |
Thermal |
Temperature |
0[deg] Radiation type: Surface-to-surface (accuracy prioritized) |
The radiation setting can be done at [Thermal Analysis tab] > [Radiation Setting] dialog box as well.
Shown below are the setting details.
The outer boundaries of the three bodies are treated as surfaces for the surface-to-surface radiation. The emissivities for each body attribute is viewed.
By clicking [Show all boundary conditions set for the body attribute], the display is switched as shown below.
As set for each item, [0] for Disk and [High Temperature Wall] for Plate_1 are displayed.
[Follow the outer boundary condition] is set to each of them and [Surface-to-surface (accuracy prioritized)] is set as an outer boundary condition. It is confirmed that all surfaces are treated as those for the surface-to-surface radiation.
The diagram below shows the temperature distribution of the upper plate.
(The body fields for the other bodies are hidden (right-click > hide body field).)
The center area is around 160[deg] whereas the other area is over 260[deg].
The disc is blocking the heat radiation.
The plot below indicates the temperature across the two points: (5, 0, 5) and (5, 10,5).