conductivity was specified, thus acting as an ideal
insulator.
5.4 Discussion
The first example of a DT with integrated Thermal
Simulations was created, examined and
thermodynamically analysed from within the DT
simulation framework.
Thus, the requirements of usability and
enhancement of time-management were met; both
secured by a central point of access for the whole
interaction with the FEA in the DT simulation
framework.
Besides, the resulting temperature distributions
and heat fluxes were the same in the DT simulation
framework as in a “pure FEA” only using the Thermal
Simulation software, which validates the interface
and the approach. Furthermore, they showed the
expected physical behaviour in accordance with other
Thermal Simulation related publications. Thus, also
the required preservation of quality of each
simulation method respectively was validated.
6 CONCLUSION
The aim of this work was the integration of Thermal
Simulations via FEA into an existing DT simulation
framework and thus expanding the scope of DTs.
In the development of the concept for this
integration, a special focus was set on the general
usability and validity. Thus, the DT environment
served as access point to conduct Thermal
Simulations of defined components. This concept
also optimizes time management, as this can be done
when critical situations occur in the application
scenario (contrary to performing an FEA at every
time step).
For the specific implementation, new extensions
for DTs were developed, which manage the
externally performed Thermal Simulations with
Z88Aurora. During the implementation, it was
necessary to convert the DT model to a model that is
FEA compatible. This was achieved by importing the
geometries from external .stl files. The
transformation of the models and the entire setup of
the Thermal Simulation was automated such that a
high degree of user-friendliness can be guaranteed.
The extensions currently include the calculation of
steady-state temperature and heat flux distributions,
where the starting point is a temperature distribution
on the surface.
7 OUTLOOK
Although a first approach of integration of Thermal
Simulations into a DT was successfully performed,
there are still opportunities for future work. For
example, more complex concepts concerning
thermodynamics could be integrated (e.g. thermal
loads due to thermal radiation, convection or electric
currents). In addition, the thermal processes might
result in geometric changes that have been neglected
so far. Thus, a combination with the structural
simulation framework for DT (Kaufmann et al.,
2018), (Kaufmann et al., 2019) will be interesting.
The same holds true for a specific application
scenario in space robotics, where heat influx is
already calculated in a DT, but not connected to FEA
(Rossmann et al., 2018).
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