Numerical simulation of the dispersion in oscillating flows with reversible and irreversible wall reactions

This is a study on the mass transport of a solute or contaminant in oscillating flows through a circular tube with a reactive wall layer. The reaction consists of a reversible component due to phase exchange between the flowing fluid and the wall layer, and an irreversible component due to absorption into the wall. The short-time dispersion characteristics are numerically investigated, incorporating the coupling effects between the flow oscillation, sorption kinetics, and retardation due to phase partitioning. The effects of various dimensionless parameters e.g., Da (the Damköhler number), α (phase partitioning number), Γ(dimensionless absorption number), and δ(dimensionless Stokes boundary layer number) on dispersion are discussed. In particular, it is found that there exist trinal peaks of the breakthrough curves in some cases.