Paper 1
Numerical and Experimental Study of
an Airing Device for Controlled Natural Ventilation of a Building
Marco Simonetti and Gian Vincenzo Fracastoro
Department of Energetics, Polytechnic of Turin, Italy
Abstract
The rationale of an advanced natural ventilation system should be to
control airflows and air temperature during winter, and to avoid
unnecessary energy losses and local draught, while maintaining an adequate
ventilation rate. On the other hand, natural driving forces (pressure head
due to buoyancy and wind) vary significantly during the heating season. A
prototype of a new device for controlled natural ventilation of buildings
has been designed with the aim of avoiding cold draughts and excessive
energy consumption during the coldest periods as well as ensuring the
right amount of airflow even during mid-seasons. The device has been
numerically studied by means of a commercial Computational Fluid Dynamics
(CFD) code and has subsequently been built and experimentally tested. The
CFD calculations were validated and used to assess the practical
possibility of controlling the very low airflow rates typical of natural
ventilation. Results will be used to investigate the comfort conditions in
a room equipped with such a device during a normal heating season.
Key words: controlled natural ventilation, CFD analysis,
experimental analysis, prototype airing (ventilation) device, heating
season.
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