Viscoelastic effect on the velocity autocorrelation function

摘要

The velocity autocorrelation function of a hard sphere moving in a simple fluid is derived from hydrodynamic fluctuation theory. The inertia effect causing slow decay at long times has been known. Now, the short time Enskog behavior can be explained adequately by including viscoelastic relaxation. The viscoelastic model so derived agrees well with the molecular dynamic calculations.