

Preprint 25/2002
On first-order corrections to the LSW-theory
Andreas Hönig, Barbara Niethammer, and Felix Otto
Contact the author: Please use for correspondence this email.
Submission date: 05. Mar. 2002
MSC-Numbers: 35B27, 74N20, 82C26
Keywords and phrases: ostwald ripening, monopole approximation, stochastic homogenization
Abstract:
The classical LSW-model describes the evolution of the radii of particles of one
phase immersed in the other phase during the last stage of a phase transformation.
Despite its simplicity, the LSW-model captures self-similar coarsening of the radii
distribution. It is derived under the assumption of vanishing volume fraction
of the particles. Unfortunately, quantitative predictions of this model do
not well agree with experiments. Hence there is a large interest in deriving
first-order corrections of the LSW-model in
.
In the first part of this paper, we present a new heuristic method to efficiently
identify the first-order correction for a statistically homogeneous (and thus infinite)
system. As was previously known, the first-order correction is of order
.
In the second part of this paper we consider finite systems (cluster). Numerical
simulations have shown a cross-over in the scaling of the correction term from
to
when the cluster becomes larger than the screening
length. We rigorously derive this cross-over for the time derivative of the
energy. Our starting point for both parts is the monopole approximation.