Comprehensive sound absorption report
Introduction
sound energy (or acoustic) is the energy transmitted or transported by sound waves. It comes from the energy of the vibration of the sound focus and propagates to the particles of the medium that they pass through in the form of kinetic energy (movement of the particles), and potential energy (changes in pressure produced in said medium or sound pressure of the volume "Volume (sound)"). As sound propagates through the medium, the energy is transmitted at the speed of the wave, but a part of the sound energy is dissipated in the form of thermal energy.[1] Acoustic energy usually has low absolute values, and its unit of measurement is the joule "Joule (unit)") (J). Although it can be calculated from other quantities such as sound intensity, other related quantities can also be calculated, such as density or acoustic energy flow.
From the definition of acoustic intensity, the acoustic energy that passes through a surface A: can be calculated.
Sound energy density
The acoustic energy density or acoustic energy per unit volume is the average amount of acoustic energy (ε) that corresponds to a unit volume. It is also equivalent to the quotient between the sound intensity and the speed of sound.[2][3] The unit of measurement is the joule per cubic meter, J/m³.
For a plane sound wave, the energy density is calculated from the root mean square power (P), the density of the medium (ρ) and the velocity (v), according to the formula:[4].
The total acoustic energy density (kinetic plus potential) is equivalent to the product of the density of the medium by the square of the speed of the particles in the direction of wave propagation.[5].
Sound energy flow
The acoustic energy flow or sound (symbolized by q) is obtained as the integral of the velocity of the particle") v times the differential of the surface A, so that only the portions of the velocity perpendicular to the surface are important.
The unit of measurement is the watt, (W).