Sound Absorption Characteristic of Glass and Plastic Bottles: Considerations of Their Dependences on Material Properties

Abstract

Great number of bottles made by glass, plastic and metal are used to store beverages, liquid ingredients as water, milk, vinegar and also liqueur. Empty bottles after usage are collected for recycling use and resources. Many of them have narrow open mouth and look like typical shape in kinds of Helmholtz resonator. Authors thought that their reuse for functional building parts with sound absorption would be very valuable from points of view of green building and environmental policies, and authors then measured each resonance frequency and sound absorption coefficient of representative, including light-soft-plastic, bottles, with net capacity from 7 to 2000 ml, by setting on the edge of sound tube with diameter of 100 mm. Sound resonances with sound absorption coefficient of 0.3–1.0 at frequencies from 100 to 1000 Hz clearly depending on the capacity could be confirmed. It was also found that measured result was well matched to the numerical calculation based on acoustic impedance change at each section area gradually changed in bottle. It is thought that combination use of recycled bottles with independent resonance frequency is more effective than use of new uniform perforated plates for wide space where we need additional sound absorption in certain frequency range.

Sound Absorbing and Insulating Low-Cost Panels from End-of-Life Household Materials for the Development of Vulnerable Contexts in Circular Economy Perspective

“…Panels made of recycled PET and sheep wool showed an absorption coefficient α higher than 0.7 in the range of 50-5700 Hz regardless of the humidity content [46]. The sound absorption of light-soft-plastic bottles with net capacity from 7 to 2000 mL is affected by the capacity in the range of 100 and 1000 Hz [47]. Plastic bottles are often used to hold materials that lack structural strength.…”

Experimental assessment of sound insulation performance of a double window with porous absorbent materials its cavity perimeter

“…Iwase studied countermeasures against the mass-air-mass resonance of a double window with porous absorbent material or a Helmholtz resonator by using a double glazing model of acrylic plates. The result of measurement of excited vibration on plates of double glazing indicates that natural frequency of the plate affects strongly reduction index of double glazing [12]. Although they presented the possibility of suppression of resonance by absorbent systems, the sound pressure response inside the cavity of the double window and the effect of the arrangement of the absorbent had not been studied in detail.…”