Published online by Cambridge University Press: 01 July 2010
The dynamics of a viscous compressible fluid, confined between two parallel plane walls and excited by a sudden impulse transverse to the walls, is studied on the basis of the linearized Navier–Stokes equations. It is shown that the time-dependent flow depends strongly on the sound velocity and on the shear and volume viscosity. Under favourable conditions an echoing effect can be observed, with a sound pulse bouncing many times between the two plates. The velocity correlation function of a Brownian particle immersed in the fluid is calculated in point approximation. It shows a similar strong dependence on fluid properties.