(251i) Molecular Effective Dispersion Under Electrical Field and Channel Curving Effects for Couette and Poiseuille Flows

Among the various geometry schematics for apparatuses utilized in the separation of solutes, including pharmaceuticals and metabolites, cylindrical devices tend to dominate because of their effectiveness and space efficiency. Applications of electrical field flow fractionation (EFFF) has allowed research to be conducted with regard to the optimization of molecular separation by the examination of a few parameters. Micro-channels that exhibit certain degree of curvature influence not only the velocity field but also the degree of solute mixing or separation. To avoid the complexity in mathematical derivations, this phenomenon is relaxed and the effect is mascaraed.

The main focus of this contribution is to broaden the options for apparatus design by investigating the effective diffusivity and optimal time of separation under Poiseuille fluid flow and making the comparison with Couette flow regimes. A theoretical spiraling device was considered in the process. The method of spatial averaging was used in obtaining the analytical expressions of the important parameters. Comparable parameter values were then explored as the correlation was made between the two different flow regimes, ultimately allowing the optimal times of separations to be juxtaposed for conclusion and analysis.