On question of determining characteristics of porous rubber for wave sound proofing

Abstract

To determine the characteristics of a distributed waveguide damper of hydrodynamic noise, it is necessary to know the magnitude of the modulus of the bulk elasticity of a material made of porous rubber with a filler in the form of metal balls filling the space between the pliable rubber wall and the rigid body. The paper considers a computational-experimental method for determining the bulk modulus of such a material. For cylindrical samples, the porosity of which was obtained by foaming in the process of vulcanization or cutting of cavities in the rubber massif, the porosity is experimentally determined; the relations of the force and volume change on the displacement are plotted. Using the experimental values of the Young’s modulus and Poisson’s coefficients for an elastic medium, the magnitude of the bulk modulus of the sample are determined.