Assessing the effect of a barrier between two rooms subjected to low frequency sound using the boundary element method

Abstract

The boundary element method (BEM) has been used to compute the acoustic wave propagation through a single vertical panel, which separates two rooms, made of concrete, when one of the rooms is excited by a steady-state, spatially sinusoidal, harmonic line load pressure at low frequencies. This work focuses on how the connection of the panel to the ceiling affects the acoustic insulation provided by the wall. Perfect double-fixed partitions and acoustic barrier-type structures with differently-sized gaps between the ceiling and the barrier are studied. The BEM model is formulated in the frequency domain and takes the air-solid interaction fully into account. Insulation dips are localised in the frequency domain and identified with dips associated with both the wall's natural dynamic vibration modes and with those associated with the air in the rooms. The influence of the wall's thickness on acoustic insulation is also analysed. The computed results obtained with the acoustic barrier type structure are compared with those obtained by a rigid model. The importance of the rooms' surface conditions is assessed, modelling the rooms with cork. #

Sandwich panels from cork and polyester in presence of epoxy resin as interfacial adhesive

“…Concentrated in the middle of the beam, the load is applied. The contact between the load and the beam is also considered as a contact point (Tadeu and Santos, 2003). When the load is gradually increased without exceeding the limit of practical strength; the beam is deformed along a determined arrow, depending on the nature of the constituent components of the beam.…”

Determination of Sound Transmission Coefficient of Gypsum Partition Walls Insulated by Cellubor™

“…One of the noteworthy works is to use the finite layer method as a numerical technique for modeling the acoustic behavior of walls (Díaz-Cereceda et al, 2012). Researchers also pointed out that, in addition to the mass and sound frequencies, some other parameters can affect acoustic insulation as well, such as the arrival angle of sound waves, weak points in insulation, hardness, and damping properties of the element (Tadeu and Santos, 2003). Moreover, investigations have also been done on the use of lightweight materials in different engineering fields because of their acoustic properties (Tadeu et al, 2004).…”

Study of Mechanical and Hygrothermal Properties of Agglomerated Cork

“…Contrary to natural cork and its limited field of application, the industrial cork covers a wide area up to thermal and acoustic insulations for space vehicles [10,11]. Agglomerated cork is obtained from granulated cork compressed in an autoclave and crossed by a water vapour flow at 350°C [12,13].…”