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W. Schneider:
"Influence of heat conducting substrates on explosive crystallization in thin layers";
Heat and Mass Transfer, 53 (2017), 9; S. 2829 - 2839.

Crystallization in a thin, initially amorphous
layer is considered. The layer is in thermal contact with a
substrate of very large dimensions. The energy equation of
the layer contains source and sink terms. The source term
is due to liberation of latent heat in the crystallization process,
while the sink term is due to conduction of heat into
the substrate. To determine the latter, the heat diffusion
equation for the substrate is solved by applying Duhamel´s
integral. Thus, the energy equation of the layer becomes
a heat diffusion equation with a time integral as an additional
term. The latter term indicates that the heat loss due
to the substrate depends on the history of the process. To
complete the set of equations, the crystallization process
is described by a rate equation for the degree of crystallization.
The governing equations are then transformed to a
moving co-ordinate system in order to analyze crystallization
waves that propagate with invariant properties. Dual
solutions are found by an asymptotic expansion for large
activation energies of molecular diffusion. By introducing
suitable variables, the results can be presented in a universal
form that comprises the influence of all non-dimensional
parameters that govern the process. Of particular
interest for applications is the prediction of a critical heat
loss parameter for the existence of crystallization waves
with invariant properties.

Explosive Crystallization, Heat Conducting

http://dx.doi.org/10.1007/s00231-017-2006-7

http://publik.tuwien.ac.at/files/publik_267832.pdf

Projektleitung Wilhelm Schneider:
AIC Androsch International Management Consulting GmbH Forschung auf dem Fachgebiet Strömungsmechanik und Thermodynamik