Objective of thesis
Tests on small-scale model in a wind tunnel
Numerical analyzes using CFD (Computational Fluid Dynamics)
Comparison of results
Four research axes were investigated for an in-depth study of Badgirs (wind towers) in Iran.
The first phase involved measurements of eleven wind towers to understand their physical and typological aspects. This research offered an overall idea about different forms of Badgir constructed since the 18th century in Iran. We have demonstrated that the specific design of natural ventilation systems depend not only on the building’s forms, but also varied to accommodate the local climate.
We found some important weaknesses on traditional Badgirs. For example, we have observed that part of the air escapes through opposite channels before descending the main column. Or, a great part of energy stored by inner walls seemed insufficient for a very hot day. In fact traditional Badgirs fail to achieve a full potential of evaporative cooling, in spite of the fountains located under the conduits.
The second phase of our research was focused on constructing three different small scale models of Badgir to test in a wind tunnel. On this occasion we studied the wind behavior in each duct. For more accuracy, the validity of theoretical assumptions was constantly verified with experimental tools. Wind tunnel tests were used to evaluate the precision of measurement methods and uncertainty of experimental results.
The third focus of our research was to draw different type of Badgirs with Gambit and analyze them with Fluent to implement a numerical simulation.
The fourth phase was to build a half-scale Badgir (scale 1/200, 6 meters high). This experience is already carried out at the University of Lyon. The construction was performed over 5 days in April 2015. The Badgir was built by the students of ENSAPM where I teach architecture at this time.