An Experimental and Numerical Investigation of Bio-Based Polyurethane Foam for Acoustical Applications

In this work, the degree of sound absorption of bio-based polyurethane foam is experimentally investigated and then numerically predicted using finite element analysis. The continued increase in the use of polyurethane foams requires designers and manufacturers to study the relevant factors affecting their production and utilisation to realise their full potential. This study examines the effects caused by synthetic foams. To overcome this issue, bio-based foams with different shapes of Luffa fibres were experimentally tested for an improved sound absorption coefficient using the impedance tube and M+p software. COMSOL Multiphysics is a powerful finite element analysis software used to numerically and analytically study the sound absorbance in the BIOT model. In general, it is believed that sound propagates through a porous material or medium such as foams and fibres. Also, it is said that this sound propagation is governed by five parameters which are mainly focused on the geometry of the porous material, namely porosity, tortuosity, flow resistivity, viscous characteristics and thermal characteristics length. So conventional laboratory methods such as the BIOT model measure these geometrical characteristics.