1. Ratings

\(P\)	:	instantaneous total pressure at a point in the fluid
\(p\)	:	averaged pressure over a straight section
\(\tilde{p}\)	:	fluctuating pressure
\(u\)	:	moving the structure
\(\Phi\)	:	potential for fluid movements
\({\mathrm{\rho }}_{0}\)	:	density of acoustic fluid
\({\mathrm{\rho }}_{s}\)	:	density of the structure
\(\omega ,f\)	:	pulsation, frequency
\(c\)	:	speed of sound in the fluid
\(\mathrm{\lambda },k\)	:	wavelength, wave number
\(s\)	:	structure stress tensor
\(\varepsilon\)	:	tensor of structural deformations
\(\text{dV}\)	:	volume element
\(\text{dA}\)	:	surface element
\(\Sigma\)	:	interaction surface between the pipe and the fluid
\({S}_{f}\)	:	right section of the fluid
\({S}_{s}\)	:	straight section of the pipe