Optimization of Acoustical Function of Sound Absorbers with Emphasis on Geometry and Height of Spaces

Subject Areas : architecture

zahra sokhandan ¹ (دانشجوی دکتری رشته معماری، دانشگاه هنر اصفهان، استان اصفهان، شهر اصفهان)
farshad nasrollahi ² (استادیار گروه معماری، دانشگاه هنر اصفهان، استان اصفهان، شهر اصفهان.)
Abas Ghafari ³ (استادیار گروه معماری، دانشگاه هنر اسلامی تبریز، استان آذربایجان شرقی، شهر تبریز)

Received: 2017-06-12 Accepted : 2018-09-10 Published : 2019-05-22

Keywords: SPL, Height of space, Proportions, Membrane Absorbers, EASE4.4,

Abstract :

In this paper, efficiency of Absorber Panels improved with the geometry of spaces and the most optimal mode of them is identified. The studied variables are position and location of installing the Absorber Panels, Geometry and Height of them, the space around the Absorber panels with an emphasis on the upper part of panels, position of Sound sources and their heights and the geometry and height of a place. The research has been done in experimental method through the observation and measurement about the Acoustical Statue of Zahra Mardani Azar Collage in Tabriz and Simulation method with EASE software. The primitive result of measurement and Simulation compared and analyzed. In the process of researching, simulating repeated over and over again to recognize the best location of Absorber panels in whole spaces of collage. The purpose is decreasing of noise and sound intensity level in Classrooms and maintaining the high intensity level of workshops with them. The problem in Zahra Mardani Azar collage in Tabriz is the high noise level around the workshops that make Acoustical pollution in the eight classrooms which are neighborhood with workshops. Because of the high cost of Absorbers panels, it is so important to use them in most the suitable place and optimal mount, so 20 square meters of Wood Absorber panels were chosen and located in different positions in one of the workshops and found out the best place for installing them. In the following absorber panel divided and installed in different position of optimal place. The most important challenge in this study is the possibility of generalization of results in all of schools with a similar plan, conditions and problems. So in the process of research, the relation between variables Studied, analyzed and documented. The purpose was finding a formula for achieving the best sound absorbing in all spaces of an educational place with different condition. Acoustical factors like STI(sound transmission index), ALC (Alcons), SPL (Sound pressure level) and noise analyzed in the case study, so SPL and noise level have been introduced as problems. Limitation in changing the geometries of schools make solving the Acoustical pollution hard in common ways, so finding a way to control the noise level in school with low cost is the challenge in this research. As a result, ceilings and Upper condition are the best location for installing the Absorber panels and floors are worst. Absorbers need some free spaces on their heads that is the proper places for sound reflections and trapping the sound there. Height of sound source is a very important factor to achieve the best efficiency in absorbing inside the places. Free spaces on sound sources are as important as free spaces on the absorber panels. In process of simulation, it has been found that height of free spaces and sound sources should be equal and height of absorbers and free space on it too. If double height of absorber and sound source make height of space, the best absorbing in space will happen.

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