We discuss some aspects of the intriguing problem of interplay between molecular diffusion and the geometry of the velocity field in the diffusion of test particles. By simple arguments one can understand how the diffusion coefficient can have a large enhancement from the combined effects of the noise and the drift terms in the Langevin equation ruling the motion of test particles. The same effects give rise to the superdiffusive transport observed in media with correlated random velocity fields.
ON THE EFFECTS OF NOISE AND DRIFT ON DIFFUSION IN FLUIDS / Crisanti, Andrea; Vulpiani, Angelo. - In: JOURNAL OF STATISTICAL PHYSICS. - ISSN 0022-4715. - STAMPA. - 70:1-2(1993), pp. 197-211. (Intervento presentato al convegno NATO ADVANCED RESEARCH WORKSHOP : STOCHASTIC RESONANCE IN PHYSICS AND BIOLOGY tenutosi a SAN DIEGO, CA nel MAR 30-APR 03, 1992) [10.1007/bf01053963].
ON THE EFFECTS OF NOISE AND DRIFT ON DIFFUSION IN FLUIDS
CRISANTI, Andrea;VULPIANI, Angelo
1993
Abstract
We discuss some aspects of the intriguing problem of interplay between molecular diffusion and the geometry of the velocity field in the diffusion of test particles. By simple arguments one can understand how the diffusion coefficient can have a large enhancement from the combined effects of the noise and the drift terms in the Langevin equation ruling the motion of test particles. The same effects give rise to the superdiffusive transport observed in media with correlated random velocity fields.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.