SOUND REDUCTION PERFORMANCE OF NOVAL WINDOWS DESIGNS FOR THE CONTROL OF INTERNAL NOISE LEVELS AND PASSIVE VENTILATION

The aim of this project is to investigate the sound reduction index (SRI) and airflow performance of novel windows designs for passive ventilation and the control of internal noise levels. Recent work, such as the ANC’s Acoustics Ventilation and Overheating: Residential design guide, aims to assist designers adopt an integrated approach. In this paper, sound reduction and airflow performance are investigated using Finite Element Modelling (FEM) validated against laboratory data obtained using the standard ISO 10140:2010. The validation shows agreement between the numerical simulated SRI and experimental results within 5%. Three novel types of window are then examined by simulation in detail. The results show the SRI of these designs to be 18, 12 and 9dB relative to an open single glazed window. In terms of ventilation performance, all three novel designs handle an airflow rate >75m3 /h, more than enough for whole dwelling ventilation and generally enough for purge and overheating ventilation requirements. The maximum average speed of the air passing through the windows is <0.16 m/s with no turbulence. These two characteristics combined assure comfort for residents and avoid regenerated noise from the window. It is concluded that these novel window designs can be practical solutions for purge ventilation and overheating problems requiring good noise reduction properties. The implication of this work is that this numerical modelling approach can be a powerful tool for the development of novel window designs for the control of internal noise levels and passive ventilation.