Dynamics of solid growth under a gravitational field: Influence of the formation of a diffusive layer

MARCOS F. CASTEZ; BÁRBARA BLUM; ROBERTO C. SALVAREZZA; HERNÁN G. SOLARI

PHYSICAL REVIEW E - STATISTICAL PHYSICS, PLASMAS, FLUIDS AND RELATED INTERDISCIPLINARY TOPICS

American Physical Society

Lugar: New York; Año: 2003 vol. 67 p. 616051 - 616058

1063-651X

   We discuss the gravitational sedimentation of particles in terms of a stochastic model considering, in view of experimental evidence, that the aggregation to the growing surface deposit is mediated by the formation of a layer of suspended particles subject to gravitational forces, thermal agitation, as well as aggregation contact forces. The aggregation of such partially buoyant particles is ruled by the rates of occurrence of the different stochastic events: incorporation to the layer of suspended particles, sedimentation, and gravitationally biased diffusion. The model introduces bridges across different standard solid on solid deposition models which can be considered as limit cases of the present one. Analytical and numerical results show that for finite realistic deposits there are different regimes of aggregation including situations in which the deposit is grown completely during the transient time of the system.