Maurizio Catalano, Dipartimento di Architettura e Urbanistica — Politecnico di Bari — Italy Tel +390805963347, Fax +390805963348, e-mail: m. catalano@poliba. it Guido R. Dell’Osso, Dipartimento di Architettura e Urbanistica — Politecnico di Bari Francesco lannone, Dipartimento di Architettura e Urbanistica — Politecnico di Bari

Introduction

Design and realisation of natural ventilation systems constitute an important subject in the research field on the ability of buildings to respond to climatic conditions. This study aims to evaluate how the stairwell can be an essential element of natural ventilation systems in low-rise buildings.

This research evaluates how parts of buildings act as an indoor microclimate control system. Computational Fluid Dynamics codes (CFD) are used in order to design/verify the behaviour of the building components as a natural ventilation system.

This study focuses on building types that are very common, like blocks of in-line houses (three — to five-storey with a single stairwell and with two apartments on each floor).

The natural ventilation system studied is characterized by easy implementation in energy retrofitting of buildings and by inexpensive installation and management. Furthermore, the related operation is quite easy.

In this study, the main innovation is the different architectural and functional conception of traditional building components, such as the stairwell. The stairwell is not only used as a chimney in order to increase the air-change rate in the cold season, but it is also used as a wind-catcher in summer.

The main results of CFD simulations concern the design of the stairwell openings (location, size, aerodynamic characteristics) and the design of an aerodynamics control system.

The behaviour of the examined natural ventilation system is governed by a very large number of parameters. The results shown concern only a certain number of the typical boundary conditions. However, these results can be useful for the designing of other similar natural ventilation systems.

Future research projects will concern the evaluation of different boundary conditions. The further aim is the definition of the most relevant parameters for the designing of similar systems.