Sound Volume Velocity is the product of particle velocity $v$ and the surface area $S$ through which an acoustic wave of frequency $f$ propagates. Also, the surface integral of the normal component of the sound particle velocity over the cross-section (through which the sound propagates). It is used to calculate acoustic impedance.
Applicable units are those of quantitykind:SoundVolumeVelocity
http://en.wikipedia.org/wiki/Acoustic_impedance
$q= vS$, where $v$ is sound particle velocity and $S$ is the surface area through which an acoustic wave of frequence $f$ propagates.