PASSIVE SYSTEMS FOR BUILDINGS INDOOR COMFORT

The paper shows the preliminary studies for the University Campus ZEB Energy realization in Palermo. The particular location in the Mediterranean basin has required careful planning to resolve the problems related to high temperatures and humidity. For this reason has been employed strategies, elements and building materials that meet the requirements of sustainability and energy savings provided by law, in order to build a new building energy self-sufficient. The University of Palermo had the need to create new spaces to be used as classrooms for different types of education and especially of a space for conferences and conventions. This type of spaces is usually very energy eater because it must be kept a continuous very high interior comfort during the hours of use. To contribute passively to the conditioning of this space, especially during the long, hot summer months, it was set up a natural cooling system, which can contribute to the lowering of the internal temperature or most of the year. This system takes advantage of cool outdoor air intake by a shaded courtyard inside the building, in this courtyard was expected a tank of water and vegetation so that air can cool off naturally by contact. The air thus cooled introduced into the conference room through the iron grids, and generates an air movement that allows to lower the internal temperature of 3-4 C° compared to the initial one. The internal air movement is guaranteed by application of extraction grids in correspondence of the opposite wall, suitably designed to ensure a draw upwards and the consequent expulsion of the exhausted air. The study of the effective lowering of the temperature was carried out through a CFD simulation program that has also allowed us to identify the circulatory flow of air. The use of this simulation program has contributed to the design so that interior comfort has been guaranteed. For example the CFD simulation has allowed to arrange the seating so that the air distribution is not dangerous for the occupant. Thanks to this occasion we have developed an energy-saving strategy that could be shared under similar climatic conditions and collective spaces that consume a lot of energy.