Process intensification through staggered herringbone micro-channels: Mass transfer enhancement to a reactive wall

Abstract

In the present study, the flow behaviour through different micro-herringbone channels configurations (1-peak, 2-peak, 1–2 alternated peak herringbone channel and a flow inversion geometry) have been numerically analysed as a mean of intensifying mass transfer to a reactive boundary. Results showed that the mass transfer coefficients were higher for the 1–2 alternated herringbone structure than those with, either, 1-peak or 2-peak structures. Moreover, the flow inversion structure mass transfer coefficients were double those obtained for the staggered herringbone channel. The alternated herringbone channel combines a different set of herringbone structures that are efficient at removing the boundary layer at different parts of the channel. The combination of these structures provide an enhanced mass transfer performance as compared to a standard herringbone channel. The obtained results showed that a 2D simplified model which uses hydrodynamic data from CFD simulations is a reasonable substitute for full 3D particle tracking simulations in terms of the mass transfer behavior of the 1PSHC with a 97.5 % of accuracy related to the asymptotic Sherwood number. The mixing capacity of the herringbones was accounted for by an apparent effective diffusion coefficient. The agreement between the 3D and 2D simulation was reasonable.