Simulation:
Settings 
Boundaries Thermal BoundariesXmin, Ymin, Zmin, Xmax, Ymax, Zmax
Boundary conditions for thermal problems can be selected independently from those for electromagnetic problems. Currently three types of boundaries are available, which are comparable to electric, magnetic and open boundaries.
The table below shows which thermal boundaries are available and how temperature and heat flow are affected.
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Temperature (T) |
Heat Flow (Q) |
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Description |
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Isothermal |
T = const. |
Q tangential = 0 |
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Heat can pass this type of boundary, but the temperature is constant. In the boundary temperature page one can define a fixed or floating temperature value. |
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Adiabatic |
d T / dN = 0 |
Q normal = 0 |
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No heat flow passes this boundary condition. The temperature distribution is not constant. |
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Open |
Lim R→∞(T) = T Background |
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Open (add space lf) |
Similar to the open boundary condition, with some extra space added between structure and applied boundary condition. |
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Example:
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The example above is a coaxial connector with a loss distribution from a hf-simulation. Usually adiabatic boundaries are applied when the structure is continued behind the boundary (e.g. when waveguide ports are used). If a device is embedded in a thermally controlled environment an isothermal boundary is advisable. For devices which operate more or less in a free surrounding the open boundary is likely the best choice.
Note: choosing the correct type of boundary is very important for a proper thermal simulation. Especially the temperature distribution is very sensitive to the boundary settings.
Open boundary...
Pressing this button opens the Settings for Open Boundaries dialog box, which offers the possibility to enter some settings regarding open boundaries. Consequently this button is only enabled if an open boundary condition is selected. The behavior of this boundary condition is very much related to the background temperature setting in the thermal solver dialog boxes (Thermal Stationary Solver / Thermal Transient Solver) .
See also
Boundary Temperature, Boundaries, Symmetry Planes, Thermal Stationary Solver, Thermal Transient Solver
