Hydrodynamics of fluids near a critical point

Because many properties of a fluid are highly anomalous near a critical point, experimental situations that normally are very simple to describe become much more complicated. Thus the specific heat of a sample is different from bulk values because of large, gravity-induced density gradients. The problems of relaxation to equilibrium, free convection, Brownian motion of a particle, and the viscous damping of an oscillating cylinder or a rotating disk are all complicated by the large compressibility, and, in general, the need to solve the hydrodynamic equations in a nonlinear regime.