Abstract :
[en] In the context of a european project dealing with the
issue of transport safety improvement in fog
conditions, an experimental building has been
constructed on the FUL campus, in the southern part
of Belgium. This building hosts a climatic chamber in
which a given indoor climate is to be maintained
(temperature and relative humidity) whatever the
external climate, in order to promote the artifical
production of fog by water droplets spraying.
During the design of the building and of the HVAC
plant, different simulation approaches were carried
out in order to evaluate and possibly optimize the
technical choices concerning:
- the building envelope
- the material for the climatic chamber
- the control strategy of the HVAC system
Two categories of simulation tools were used to solve
the different tasks:
- building simulation tools
- CFD programs
For the first category, simulations were performed
using both ESP-r and TRNSYS with the objective of
solving the following questions: optimization of the
building envelope (orientation and shading of the
building, insulation, fenestration); sizing of the HVAC
system; comparison of control strategies (direct
control, indirect control, radiative and/or convective
conditioning); estimation of energy consumption and
comfort
Within the second category, the FLUENT and ESP-r
software were used and compared in order to predict
the homogeneity of the thermal state within the test
room and to calculate the effect of injecting a high
amount of small water droplets on fog production,
maintenance and visibility. Therefore, the ESP-r CFD
module program was augmented with a specific model
of water droplet diffusion.
The paper will tackle the main modelling assumptions
at the basis of each simulation experiment, the data
preparation and the results of the calculations. For
each phase, advantages and limitations of the
simulation approach will be highlighted.
These developments are considered as a first step
towards the implementation of a virtual testing
environment in the field of automotive transport
which could be complemented by additional issues
dealing with passengers comfort, acoustics, air
quality, level of illuminance generated by the virtual production of fog.
