Stokes's Law of Sound Attenuation
Stokes’s law of sound attenuation is a formula for the attenuation of sound in a Newtonian fluid, such as water or air, due to the fluid’s viscosity. It states that the amplitude of a plane wave decreases exponentially with distance traveled, at a rate α given by the formula shown here.
The law and its derivation were published in 1845 by physicist G. G. Stokes, who also developed the well-known Stokes’s law for the friction force in fluid motion.Related formulas
|α||attenuation rate (1/m)|
|η||dynamic viscosity coefficient (pascal*s)|
|ω||sound's angular frequency (1/s)|
|ρ||fluid density (kg/m3)|
|V||speed of sound in the medium (m/s)|