Simulation with açaí fiber panels for improving speech intelligibility in classroom

Abstract Speech intelligibility in classrooms and students' learning capabilities are compromised by ambient noise and excessive reverberation, causing lack of concentration, tiredness and stress. The motivation for this study was the need for appropriate acoustic conditions in classrooms, where speech is the main sound source. In order to find a solution based on environmentally sustainable acoustic absorbers, this paper investigates the acoustical applications of açaí seed fibre, an abundant vegetable fibre in the Amazon region. Initially, measurements of acoustic parameters (Reverberation Time, Initial Decay Time, Clarity, Definition and Rapid Speech Transmission Index) were made in a classroom and then an acoustic numerical model of the room was developed. After validating the model, various configurations of absorber panels made with açaí fibre were analysed in the model to verify the influence on the acoustic quality of the investigated classroom. The results of the simulations indicate that açaífibre boards can be a very attractive solution, combining low cost and good performance.