Acoustics and Noise Control

Research in this theme aims to integrate engineering and perceptual approaches to the solution of acoustic problems in the built environment.

Studies have shown that engineering noise control solutions are not sufficient for dealing with today's acoustical challenges, as multiple factors affect sound and its perception. The research focus of the acoustics theme is therefore in line with the broader soundscape approach, which relies on both physical characteristics and mental perception of the aural environment. Soundscape research is multidisciplinary by nature, as it combines engineering and social science methodologies, in view of developing qualitative solutions aimed at improving quality of life and comfort. An example of research recently carried out is given by the acoustical and perceptual analysis of water generated sounds for road traffic noise masking (see Case Study below).

Alongside soundscape research, we have expertise in sound transmission through buildings and, in particular, mathematical models which can predict the performance of entire buildings, as well as classroom acoustics and hospital noise research. Our main areas of interest include:

• Soundscapes of the Built Environment
• Environmental Noise
• Building Acoustics
• Room Acoustics

The School of Energy, Geoscience, Infrastructure and Society (EGIS) has excellent facilities in acoustics. The specialised laboratories of the School include an anechoic and reverberant chamber, and horizontal and vertical sound transmission suites. This is supported by a wide range of equipment and instrumentation. A variety of test procedures can be carried out in our facilities, which are available for hire.

Case Study

Acoustical design of water features and their use for road traffic noise masking

The acoustic use of water features is increasingly being considered in the built environment due to the inherent positive qualities of water sounds and their ability to mask noise. Research has been recently carried out by the group to identify how design can affect the acoustic of water generated sounds, as well as their perception in relation to road traffic noise masking. The work has been based on extensive laboratory measurements made on waterfalls, cascades and fountains.

The rig structure used for tests allowed the effects of design factors on acoustical and psychoacoustical parameters to be examined, including the effects of flow rate, source's height, waterfall's width, waterfall's edge characteristics and impact material. Results showed that a great variety of water sounds can be produced, and that estimations can be made on how design factors affect acoustical and psychoacoustical properties. Additionally, auditory tests have been undertaken to identify the preferred sound pressure level of water sounds over road traffic noise, as well as the preferred water sounds in the presence of road traffic noise. The findings obtained have been correlated with the acoustical and psychoacoustical properties of the water generated sounds, therefore allowing to identify the preferred water feature's designs for road traffic noise masking.