A massive intruder in a homogeneously driven granular fluid, in dilute configurations, performs a memory- less Brownian motion with drag and temperature simply related to the average density and temperature of the fluid. At volume fraction ~10-50% the intruder's velocity correlates with the local fluid velocity field: such situation is approximately described by a system of coupled linear Langevin equations equivalent to a generalized Brownian motion with memory. Here one may verify the breakdown of the Fluctuation- Dissipation relation and the presence of a net entropy flux - from the fluid to the intruder-whose fluctuations satisfy the Fluctuation Relation. © Springer-Verlag 2012.
Dynamics of a massive intruder in a homogeneously driven granular fluid
Sarracino, A.;
2012
Abstract
A massive intruder in a homogeneously driven granular fluid, in dilute configurations, performs a memory- less Brownian motion with drag and temperature simply related to the average density and temperature of the fluid. At volume fraction ~10-50% the intruder's velocity correlates with the local fluid velocity field: such situation is approximately described by a system of coupled linear Langevin equations equivalent to a generalized Brownian motion with memory. Here one may verify the breakdown of the Fluctuation- Dissipation relation and the presence of a net entropy flux - from the fluid to the intruder-whose fluctuations satisfy the Fluctuation Relation. © Springer-Verlag 2012.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
