New studies and reports are published on a daily basis about the dangers of climate
change and its main causes: humanity’s constantly growing population, the built environment
and resource consumption. The built environment is responsible for approx. 40% of
the total energy consumption, and a significant part comes from maintaining an appropriate
indoor comfort environment by heating ventilation and air conditioning. Though contemporary
studies have achieved a wide knowledge about natural ventilation and passive air conducting
systems (PACS) and their applicability, further investigations are necessary to deepen
the aerodynamic topology of air conducting building structures’ shape properties.
Hence, in our current research we conducted a series of tests applying different wind
catcher geometries. The methodology of this work is based on the authors’ previous
work, where passive air conduction systems were compared with different airflow directions
via computational fluid dynamic simulations (CFD). After finding the better performing
PACS (a downdraught system), this research evaluates whether further improvements
in ventilation efficiency are possible due to the aerodynamic shaping of the roof
integrated inlet structures. Four different wind catcher geometries were examined
to determine the most advantageous dimensional settings in the natural ventilation
system’s given boundaries. After multiple series of basic and developed calculation
runs, diverse shape designs of the passive air conduction inlet (PACI) were examined,
including wind deflector geometries. The initial reference wind catcher’s air change
rate was increased by approx. 11%. The results deliver the potential measure of improvements
achievable in the aerodynamic shape design of structures under identic conditions
of the same building domain. As a consequence, more sophisticated natural ventilation
structural solutions will be possible in more operation cost- and performance-effective
ways.
