Numerical simulation of ancient natural ventilation systems of historical buildings. A case study in Palermo

Some architectural structures inside historical buildings are often interpreted as cooling systems. The problem is the knowledge about the real functioning of these systems during the past and at the present. Full scale measurements can provide data on ventilation rate, airflow distribution, mean air velocity around and inside a building, but these experiments are really expensive and time consuming. In this paper, the airflow patterns, distribution and velocity and the air temperature distribution inside a historical building in Palermo (Italy) were investigated by a transient simulation. A three-dimensional model of the library room, actually used as book deposit, where an ancient natural ventilation system is operating, was investigated using a CFD tool during the hottest day of the summer of 2006 in Palermo. The simulation results are in agreement with the trends of air velocity and temperature of the experimental values measured during a test campaign.