This title appears in the Scientific Report :
2009
Please use the identifier:
http://dx.doi.org/10.1103/PhysRevE.80.061134 in citations.
Please use the identifier: http://hdl.handle.net/2128/9318 in citations.
Persistent memory of diffusing particles
Persistent memory of diffusing particles
The variance of the advection-diffusion processes with variable coefficients is exactly decomposed as a sum of dispersion terms and memory terms consisting of correlations between velocity and initial positions. For random initial conditions, the memory terms quantify the departure of the preasympto...
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Personal Name(s): | Suciu, N. |
---|---|
Vamos, C. / Radu, F.A. / Vereecken, H. / Knabner, P. | |
Contributing Institute: |
Agrosphäre; ICG-4 JARA - HPC; JARA-HPC |
Published in: | Physical Review E Physical review / E, 80 80 (2009 2009) 6 6, S. 061134 061134 |
Imprint: |
College Park, Md.
APS
2009
2009-12-28 2009-12-01 |
Physical Description: |
061134-1 |
DOI: |
10.1103/PhysRevE.80.061134 |
Document Type: |
Journal Article |
Research Program: |
Terrestrische Umwelt |
Series Title: |
Physical Review E
80 |
Subject (ZB): | |
Link: |
Get full text OpenAccess OpenAccess |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/9318 in citations.
The variance of the advection-diffusion processes with variable coefficients is exactly decomposed as a sum of dispersion terms and memory terms consisting of correlations between velocity and initial positions. For random initial conditions, the memory terms quantify the departure of the preasymptotic variance from the time-linear diffusive behavior. For deterministic initial conditions, the memory terms account for the memory of the initial positions of the diffusing particles. Numerical simulations based on a global random walk algorithm show that the influence of the initial distribution of the cloud of particles is felt over hundreds of dimensionless times. In case of diffusion in random velocity fields with finite correlation range the particles forget the initial positions in the long-time limit and the variance is self-averaging, with clear tendency toward normal diffusion. |