Comparison between the Sekerka-Perera model in strictly zero-gravity environment and the Sekerka-Perera model adapted to terrestrial conditions
by
Agneta M. Balint
University of the West Timisoara, Department of Physics
Coauthors: Monica Mihailovici (Main author, University of the West Timisoara), Stefan Balint (University of the West Timisoara)

Sekerka and Perera have proposed a model, which describes isothermal interdiffusion in strictly zero-gravity environment. This model is more general than the Oberbeck-Boussinesq model.

Sekerka and Perera consider perturbation expansions of mass fraction of the second chemical component of a binary solution, pressure, velocity and chemical flux with respect to a small parameter alpha. The main conclusion they obtain is the fact, that at first order in alpha the fluid motion which accompanies chemical diffusion in a liquid diffusion couple in strictly zero-gravity is the sum of an average flow, having a non-zero divergence, and a solenoidal flow. The non-solenoidal flow dominates for sufficiently small gravity. In our paper we present an adaption to terrestrial conditions of the Sekerka-Perera model. Making calculus which follow the same stages like those made by Sekerka and Perera, we conclude, that at first order approximation in perturbation the velocity field will be non-solenoidal and independent on the gravity acceleration.

Date received: January 13, 2000